Hydroxychloroquine in prophylaxis of pulmonary embolism following hip arthroplasty. Two thousand one hundred and forty four patients received Plaquenil (hydroxychloroquine sulphate) prior to total hip arthroplasty; the drug was continued until the patient was fully mobile. Fatal emboli (confirmed by postmortem) occurred in 0.28% and non-fatal emboli (diagnosed clinically) occurred in 4.15%. This was a statistically significant improvement over the overall results of all previous prophylactic measures used in this unit. The results of Plaquenil are significantly better than the most effective agent previously used in this unit, namely, Dindevan (phenindione). There were no deaths and no serious gastrointestinal or genitourinary bleeding. Allergic rashes occurred in 18 patients (0.8%), temporary blurring of vision in 6 (0.3%), and minor gastrointestinal upsets, including nausea, vomiting and minor bleeding in 12 (0.6%).


Deyerle fixation for intracapsular fractures of the femoral neck. The results of the Deyerle method of pin plate fixation for intracapsular fracture of the neck of the femur are less satisfactory than the results in the original literature. We treated 143 intrascapsular neck fractures of the femur by the Deyerle method during the period from 1969 to 1975. Seventy-four patients had follow-ups of one year or had a major complication leading to failure prior to one year for evaluation. The failures were the result of avascular necrosis in 17.6% of the patients, non-union in 27% of the patients, and pin breakage in 1.35% of patients. Eight cases with combined avascular necrosis and non-union resulted in an overall failure rate of 26 patients or 35% of the 74 patients. These observations corroborate other reports in the literature on a high failure rate with multiple pin and plate fixation.


Synovial chondromatosis in association with Turner's syndrome: a case report. A unique case of Turner's syndrome in association with synovial chondromatosis suggests that other cases with this association should be investigated to determine whether the occurrence of the 2 disease processes is coincidental.


Correlation between muscle shortening and derangement of the hip joint in children with spastic cerebral palsy. From clinical studies on hip derangement and measurement of muscle shortening around the hip joint in 244 patients with spastic cerebral palsy, we found that the incidence of subluxation was 17.0% and that of dislocation was 8.2%; there was no dislocation in ambulatory spastics and the incidence of hip derangement was high in non-ambulatory patients; significant shortening of the adductors was closely correlated with hip derangement; the combination of damaged flexors, hamstrings and adductors led to hip derangement; surgical intervention in the adductors, the flexors (particularly the iliopsoas muscle) and the hamstrings should be considered in the treatment of advanced hip derangement in patients with cerebral palsy.


Subchondral cyst of bone: a case report. This is a report of a subchondral cyst of the entire fibular head in a 24-year-old woman, and a survey of the literature including pathogenesis, histopathology, and management. Subchondral bone cyst in this location seems not to have been reported previously. The treatment was excision of the head of the fibula.


Popliteal cyst mimicking thrombophlebitis as the first indication of knee disease. Five patients, none of whom were previously known to have knee disease, developed leg swelling which was misdiagnosed as thrombophlebitis. Four were treated with anticoagulants and one developed a large calf hematoma requiring fasciotomy. The primary physicians failed to appreciate evidence of knee disease in these patients, although the rheumatology consultant found knee effusion, and a popliteal cyst was found by arthrography or ultrasonography in every case. The occurrence of popliteal cyst as the first sign of knee disease emphasizes the importance of careful examination of the knee in all patients with a clinical picture of thrombophlebitis.


Role of radionuclide joint imaging in high tibial osteotomy. The importance of a preoperative bone scan before tibial osteotomy is to detect the extent of specific compartmental involvement of the osteoarthritic knee. It is not necessary to obtain a bone scan in every case, but when difficulty arises in the selection of patients for surgery, whether the opposite compartment is involved by disease or not, a preoperative bone scan becomes useful and may eliminate the need for other procedures such as arthroscopy and arthrotomy. In a series of cases of osteotomy in 21 knees of 22 patients, with an average follow-up of 15 months, all had a preoperative bone scan, 14 repeated postoperatively. Satisfactory functional results were obtained in 71%.


Changes in bone mineral content following tibia shaft fractures. The bone mineral content of the upper ends of the tibia and the fibula was measured in 27 patients with tibia shaft fracture. The bone mineral decreased rapidly after fracture, the loss continuing for about 5 months. Later, towards the end of the first year after the injury, there was a slow restoration of mineral but no return to initial values in most instances. Although the average maximum loss was approximately 45%, only 25% of the initial bone mineral was missing after one year.


The relationship of the accessory navicular to the development of the flat foot. The Kidner procedure has been the most frequently recommended form of surgical treatment for the painful accessory navicular. This formal relocation of the posterior tibial tendon is said to restore the dynamic balance to the foot which is lost when the posterior tibial tendon gives an abnormal insertion into the accessory ossicle. The literature was reviewed to ascertain what is known or what is believed about the accessory navicular and the role of the posterior tibial tendon in the support of the longitudinal arch of the foot. Eighteen patients who had simple excision of the accessory navicular were reviewed to assess the success of such a procedure. In follow-up they all had very satisfactory results. A second group of 208 patients with non-traumatic foot complaints were reviewed to determine the incidence of accessory navicular and its association with the flat foot. Twenty-nine cases of previously undetected accessory navicular were identified in this group giving us a total of 179 patients without accessory navicular and 49 patients with accessory navicular available for study. There was no significant difference between the arch in these 2 groups of patients. Based on the findings in this study, the accessory navicular plays no role in the development of a flat foot. Simple excision of the prominent ossicle seems to be the surgical procedure of choice when conservative means of management fail.


Primary skeletal infections in heroin users: a clinical characterization, diagnosis and therapy. Experience with 24 patients and 101 cases reported in the English literature demonstrate that primary skeletal infections occur in heroin users. In young individuals with no significant underlying disease, predominant involvement in the lumbar vertebrae and sternoclavicular joint, Pseudomonas aeruginosa was the dominant pathogen. Clinical manifestations, except for pain or local tenderness, and laboratory findings were of limited value. Diagnosis ultimately depended on isolation of the pathogens from either bone or joint fluid. The treatment, as indicated, was prolonged parenteral antibiotics, generally with an aminoglycoside, incision and drainage, and immobilization.


Erythromelalgia.

Erythromelalgia. Erythromelalgia is an extraordinary disorder of unknown etiology and pathophysiology that resembles the post-traumatic reflex dystrophy syndromes but has not been described previously in the orthopedic literature. Its distinctive triad of intense burning extremity pain associated with erythema and increased skin temperature are diagnostic. Primary or idiopathic and a secondary or associated form have been identified. The latter occurs in association with an underlying disease process, especially myeloproliferative disorders. Treatment with pharmacologic agents and surgery are ineffective except in the secondary group where treatment of the associated disorder generally results in a remission. Symptoms in the primary group can be minimized by appropriate environmental control with cooling and avoiding heat-producing situations that would raise skin temperature above a critical thermal threshold.


Lower extremity fractures simulating infection in myelomeningocele. Thirteen patients with myelomeningocele sustained 33 fractures of the lower extremity. Fourteen fractures were accompanied by increased local heat, swelling, redness and a systemic response, including an elevated temperature and leukocyte count. Diagnosis of these fractures, which occur without a significant history of trauma, requires special roentgenographic studies. If routine films fail to reveal a fracture in a swollen red extremity in patients with myelomeningocele, stress films should be obtained in the area of the major swelling or where clinical pseudo-motion is suspected. The proper treatment of these fractures and the associated elevated temperature is immobilization. When these injuries are immobilized, the leukocyte count and temperature quickly return to normal.


Extension contracture of the knees in patients with meningomyelocele. In 4 patients with meningomyelocele and extension contracture of the knee (7 knees), a surgical operation is described to release the extension contracture and provide better sitting position with the knees flexed. This decreases the chance of fracture by reducing the lever arm of the lower extremity.


Osteochondritis dissecans of the talus: the natural history. An assessment of 10 patients with osteochondral lesions of the medial or lateral articular surface of the talar dome was based, first on subjective symptoms and second, on an analysis of weight-bearing anteroposterior and lateral X-rays of both ankles. The mean period of follow-up was 15 years 11 months (range 7 to 28 years). In 5 of the 6 patients treated conservatively, radiologic assessment showed that the lesion had failed to heal, but nevertheless in each instance the ankle joint was relatively asymptomatic. Talocrural osteoarthrosis developed in only 2 ankles and was considered to be an uncommon complication in those joints treated either conservatively or by excision of the osteochondral fragment.


Bursal osteochondromatosis: a case report. True osteochondromatosis in bursae not in communication with joint cavities is rare and occurred overlying a femoral exostosis in a 35-year-old man. The original cartilage nodules were converted to bone through the process of enchondral ossification.


A long-term prospective study of the Hauser and Roux-Goldthwait procedures for recurrent patellar dislocation. In a prospective study extending from 1966 to 1974, the results of the Hauser procedure were compared with the Roux-Goldthwait procedure for the correction of recurrent dislocations of the patella. In 87 knees in 75 patients, repaired consecutively and in a random manner with one procedure or the other, 100% retrieval was achieved. The average follow-up period was 7.7 years. Significant complications, though not necessarily of long term, occurred in 24 of 47 knees receiving Hauser repairs as compared with 6 of 40 knees in the Roux-Goldthwait group. Satisfactory long-term results were obtained in 72% with the Hauser technique and 93% with the Roux-Goldthwait technique.


Hormonal factors in osteoporosis.

Hormonal factors in osteoporosis. Primary osteoporosis is a ubiquitous disease of unknown etiology. The condition undoubtedly has multiple causes and the metabolic pattern of bone loss may vary significantly from case to case. Five hormones, PTH, gonadal steroids, CT, T3 and T4, and glucocorticoids, and possibly a sixth, GH, have fundamental actions on bone metabolism and may therefore be causally involved in primary osteoporosis. A consideration of selected data on hormonal interactions culled from a much larger body of experimental and clinical data leads to the conclusion that in vitro studies, animal research, and data obtained in postmenopausal women with age-related bone atrophy, but not osteoporosis, have yielded considerable data relating to bone metabolism, but have failed to define the causes or treatment of primary osteoporosis. There has been excessive emphasis on hormonal reactions relating to bone metabolism and bone cell function, and too little concern for nonhormonal factors which might influence the kinetics of skeletal turnover through alterations in bone cell activity. A practical approach to the cause(s) and treatment in the only suitable model, the human with osteoporosis, is proposed with the expectation that a better insight into the pathogenesis of the condition will be achieved.


Early diagnosis of disk space infection with 67Ga in an experimental model. Both 67Ga and 99mTc scans become positive in experimental disk space infection, but 67Ga does so earlier than 99mTc. The radiologic features of experimental disk infection are similar to those seen clinically. Disk infection commences primarily in the disk and not in the vertebral body. Gallium-67 is useful in diagnosis of the disease under circumstances when the diagnosis is in doubt.


Correlation of a bioassay with the clinical status of patients with rheumatoid arthritis. Joint synovia and fluids taken from patients with various stages of rheumatoid arthritis (RA) were injected into embryonated chicken eggs, resulting in characteristic joint abnormalities ("crooked toes") in the extremities of the embryos and chicks. There was a direct correlation between the number of the induced lesions and the stages of the human RA disease. The percentage of abnormality of the bioassays was consistent with acute, subacute, chronic or remission phases in the clinical course of the RA disease. Specimens from chronic or remission RA joints produced few or no experimental abnormalities, suggesting few or no infectiojs RA particles available to the bioassay. Likewise, dilution of acute RA joint fluids of 1 : 100 by 0.15M NaCl resulted in a characteristic extinction of the bioassay test, suggesting that specimens could lose their reactivity in the bioassay because of too great dilution in the preparation of homogenates of the synovia. Numerical changes in the bioassay consistently followed the changes in the clinical courses of the RA during waning and waxing episodes. A useful numerical scale (0--100%) of the 10-day embryonated egg bioassay as an indication or measurement of the severity of the RA in the patient is proposed on the basis of these observations.


Semitendinosus tenodesis for recurrent subluxation or dislocation of the patella. In 26 knees treated by semitendinosus tenodesis, there was no recurrence of dislocation, but fair and poor results totaled 38% due to persistent pain because of chondromalacia of the patella. Poor results are also more common in the patients with generalized ligamentous laxity. Postoperative complications in wound healing suggest that the medial parapatellar skin incision is less than adequate. Semitendinosus tenodesis with or without modifications is a useful procedure to prevent recurrent dislocations and subluxation during the growth period.


Nicolas Andry Award. Increased tissue pressure and its effects on muscle oxygenation in level and elevated human limbs. Increased tissue pressure is an important cause of local circulatory compromise. In both rabbit and human model systems known external pressures were applied to otherwise normal limbs. Side-by-side comparison of the wick and the infusion techniques revealed that both methods of pressure measurement yielded essentially identical results when tissue pressure was elevated. Measured tissue pressure significantly exceeded the external pressure applied to the limb. Using a mass spectrometer-Teflon membrane catheter system, we monitored muscle PO2 and PCO2 at different applied pressures. Muscle PO2 decreased progressively with increasing tissue pressure but did not approach zero until tissue pressure exceeded local arterial pressure. Comparison of results with level and elevated limbs indicated that elevation of an extremity dramatically lowered its tolerance for increased tissue pressure. Although they may be clinically useful modalities, these are conditions in which compression and elevation have a significant potential for compromising local circulation.


The effect of temporary exercising of a joint during an immobilization period: an experimental study on rabbits. The right hind limbs of adult rabbits were immobilized for 5 weeks. The rabbits were then allowed to move freely for 8 weeks. The rabbits of the control group were immobilized uninterruptedly. In a second group of rabbits the plaster was removed during the immobilization period 6 days a week for 5 minutes for careful exercise and in a third group of rabbits, for violent exercise. The temporary careful exercise was of no benefit and was sometimes harmful, and the violent exercise was usually injurious for the immobilized knees as regards the stiffening, thickening and the development of radiologically detectable degenerative changes.


Enhancement of healing in osteochondral defects by collagen sponge implants. Implants of porous, highly cross-linked collagen sponge (CS) were tested for their capacity to enhance the healing of osteochondral defects in rabbits. Comparison was made to the healing of similar defects with polyvinyl alcohol sponge (PVAS) implants and with no implants (CONT). Evaluation was carried out up to 44 weeks following implantation and included observation of host cellular response, biodegradability of implant, gross appearance of restored joint surface, collagenous architecture of repair tissue, and properties of the junctions of implants and host articular cartilage, subchondral bone, and medullary bone. Collagen sponge proved most effective in promoting healing of osteochondral defects with fibrous and fibrocartilaginous tissue over restored subchondral bone. Collagen sponge showed many desirable properties as a potential material for biologic resurfacing of damaged joints. These properties included porosity, biodegradability, biocompatability, ability to mechanically protect cells and matrix while directing cell ingrowth, and an available chemical technology for modifying its biomechanical and biological properties. Comparative analysis of results of healing of CS, PVAS, and CONT osteochondral defects suggest rational design criteria for implant materials to improve their effectiveness in restoration of articular surfaces.


Proximal and distal reconstruction of the extensor mechanism for patellar subluxation. Proximal and distal reconstruction of the leg extensor mechanisms has been developed and performed in 346 cases over a period of 25 years. Proximal extensor mechanism reconstruction produces very satisfactory results in over 70% of cases and continues to be the basic principle of surgical treatment for patellar subluxation. In patients with Q angles (angle between line of the quadriceps force and the direction of the patellar tendon) greater than 10 degrees distal reconstruction (patellar tendon transfer) is done in addition to, not in lieu of, the dynamic proximal reconstruction. Treatment of the chondromalacia developing secondary to altered extensor mechanism mechanics can be by simple chondrectomy provided that the causal mechanical abnormalities are modified.


Tibial tubercle transfer: a long-range follow-up study. The prime indications for tibial tubercle transfer are 2 or more complete patellar dislocations with trivial trauma or recurrent subluxation with or without pain causing "giving way." A high "Q" angle, flat lateral condyle, aplastic patella or positive apprehension test may be associated but are not always prime indications in surgery. Methods of fixation are of individual preference in this series and a single screw sufficed. An arthrotomy is not always necessary but is suggested if indicated. If the proximal tibial epiphysis is open, corrective measures are suggested that do not involve the extension of the proximal tibial epiphysis into the tibial tubercle. The tubercle should be advanced to compensate for patella alta and lined up with the femoral shaft. Transplantation of the tubercle medially 3/4'' and distally 1/2'' was generally satisfactory in a series of 377 operations with an average follow up of 3 1/2 years.


The arthroscope in the diagnosis of disorders of the patellofemoral joint. Despite our current knowledge and accumulated information, orthopedic surgeons often experience difficulties in the diagnosis of internal derangement of the knee. Too often, the admission diagnosis I.D.K. means "I don't know." Disorders of the patellofemoral joint contribute to this difficulty and may simulate torn menisci and loose bodies, as well as the instability which results from rotary displacement. Patients often have difficulty describing and locating their symptoms, and 2 or more pathologic lesions may be present in the same joint. Early lesions involving the articular cartilage are especially difficult to diagnose. Even the most astute clinician cannot rely entirely on his clinical judgement, and, at times, needs the assistance of other diagnostic measures. Arthroscopy is an invaluable aid in the diagnosis of all intra-articular pathology, permitting the proper incision in the proper area, often eliminating the necessity of opening the joint and always avoiding unnecessary meniscectomy.


Patellar biomechanics.

Patellar biomechanics. The patella is an important functional component of the knee extension mechanism. It accounts for 13 to 30% of the knee extensors' moment arm. Functional deficits owing to patellectomy include decreased knee extension power, extension lag, instability, chronic effusion, decreased stance phase flexion, alteration of the path of instant flexion centers and decreased flexion range.


Chondromalacia patellae: a system of classification. Degeneration of the cartilage on the under surface of the patella is shown to be the most frequent cause of "internal derangement of the knee" (63%). The axial view of the patellofemoral joint in 4 angles of flexion constitutes the procedure of choice for diagnostic exploration of patellar cartilage with, perhaps, the restriction for the medial compartment where arthroscopy is probably preferrable. The information obtained from single contrast arthrography of the patellofemoral joint has contributed greatly to the understanding of the sometimes confusing problem of chondromalacia of the patella. It has given an anatomic basis to the patellar syndrome and has served as a basis for a precise typographic system of classification. From this, we have been able to correlate localization and etiology which has then allowed logical solutions to be proposed for each group, based upon biomechanical considerations in both the frontal and saggital planes of the knee.


Proximal "tube" realignment of the patella for chondromalacia patellae. In young people complaining of patellar pain there is often an anatomic basis (an increased quadriceps angle or a high-riding patella). Forty-eight knees with one or other of these abnormalities underwent proximal quadriceps realignment. The results were excellent or good in 94%. Shaving of chondromalacic cartilage was also done in 11 knees but did not seem to improve the results, and is not now recommended except for "blister" lesions. Extensor mechanism dysplasia is an etiologically correct name for the disorder and therefore preferable to "chondromalacia patellae."


Mechanics and osteoarthritis of the patellofemoral joint. Patellofemoral articular pressure, either when unevenly distributed or too high for the resistance of the tissues, results in osteoarthritis. Forward or forward and medial displacement of the tibial tuberosity has provided a satisfactory method of treatment.


Spongialization: a new treatment for diseased patellae. Spongialization is an extension of the concept of Pridie for resurfacing damaged joints. The diseased cartilage is excised and the subchondral plate completely removed exposing the cancellous bone or "spongiosa" from which a new fibrous tissue surface can grow. The technique is particularly applicable to a localized lesion of the patella. Eighty-five patients who had patellar spongialization and were followed from 6--36 months (average 15 months) are reported, with 79% reporting good or excellent results. Provided that there was severe cartilage damage in each case, the early results are better than with either patellectomy or "shaving" of the diseased cartilage.


Patellectomy: a clinical study and biomechanical evaluation. This study presents a long-term follow-up and evaluation of a single technique of patellectomy involving a cruciform repair of the extensor mechanism. The techniques of evaluation, namely: clinical observation, instant center analysis and an acoustical method of cartilage evaluation provide a more thorough and objective basis for clinical study than previously reported. Cruciform repair produced results comparable to conventional methods of surgical repairs. Patellectomized knees function well in people with patellofemoral disease but not in those with panarticular disease. Patellectomy substantially alters normal joint mechanics as evidenced by persistent changes in instant center analysis. Degenerative changes caused by the patellectomy are progressive. In view of newer concepts of the function of the patella in normal joint mechanics and improved designs of total knee arthroplasty, the indications for patellectomy are now more questionable than ever before in the history of orthopedics.


Biomechanics of the patellofemoral joint. The patellofemoral joint contains 2 complex mechanisms for ameliorating forces transmitted across it, namely increasing extensor lever arm-r in the important range of flexion 30 degrees-70 degrees and increasing contact area with increasing flexion. In this range the patella bears sole responsibility for transmitting resultant flexion of quadriceps force to the femur. Here lies the thickest cartilage in the body and perhaps not surprisingly, the most frequent site of cartilage degeneration. The Q-angle and valgus vector explain the predominance of the pathologic lesions on the lateral side of the joint as well as the associated dislocations, subluxations, lateral pressure syndromes, and patellofemoral arthrosis. Extension exercises against resistance produce non-physiologic loading of patellar articular cartilage. Even relatively small loads which are commonly used in physical therapy departments produce pressures far in excess of normal activities, such as stair climbing or squatting. Patients who are placed on such exercise programs are often made worse and develop symptoms which they did not have before. Straight leg raising with weights, on the other hand, maximally stresses the quadriceps muscle without any patellofemoral compression since the patella is out of contact, proximal to the trochlea.


Prosthetic resurfacing of the patella.

Prosthetic resurfacing of the patella. Accumulated data from many sources seem to indicate that prosthetic resurfacing of the patella may be an acceptable alternative to patellectomy in the treatment of chondromalacia patellae or patellofemoral arthrosis. A patellar prosthesis which is made of cobalt-chromium alloy is attached to a remnant of the original patella by means of the acrylic cement, polymethyl methacrylate. An analysis fo the results of the use of this prosthesis in 14 knees of 13 patients reveals excellent or good results in 13 cases and one poor result. The longest follow-up period was 2 years and 9 months and the shortest was 6 weeks. Based on current experience and the experience of others, prosthetic resurfacing of the patella may give the patient some years of pain-free patellofemoral function. This is especially true in patients with poor quadriceps reserve in whom the lever-arm distance of the extensor torque should be maiwtained. Until the ideal resurfacing material is developed, the use of presently available patellar prostheses with or without femoral prosthetic components, is recommended for further investigation.


Patellofemoral replacement.

Patellofemoral replacement. From an analysis of the clinical evaluation of 85 cases and subsequent revisionary procedures, patients for isolated patellofemoral joint replacements should be carefully selected. At the present time, the primary indications are distortion or severe degeneration of the femoral groove.


Arthroplasty of the knee.

Arthroplasty of the knee. A stable polycentric knee mechanism which allows axial rotation as well as simulating other knee movements was introduced into clinical use in 1971. The surgical and mechanical problems that presented over the past 7 1/2 years have greatly helped in improving our understanding of knee reconstruction and design. A patient satisfaction rate of 95% compares favorably with the results achieved with hip arthroplasty but the complexity of knee reconstruction far outweights that of the hip.


Spherocentric knee arthroplasty.

Spherocentric knee arthroplasty. The spherocentric knee, designed to allow triaxial rotation and provide intrinsic stability, includes desirable design features of metal on high density polyethelene bearing surfaces, metal support for all plastic components, metal-cement-bone interfacing for all fixation surfaces, sufficient strength to eliminate fatigue fracture of metallic components as a potential source of failure, cam deceleration for hyperextension control, and an inverted central plastic socket which minimizes wear. The system assures a low coefficient of friction and thereby minimizes loosening. This prosthesis has been used for surgical arthroplasty in 134 knees with gross instability or severe fixed deformity or both, in which optimal results would not have been anticipated with non-articulated resurfacing prostheses. The patients have been followed for an average of nearly 3 years (range one to 5 years). Results in terms of correction of deformity, improvement of stability, range of motion, pain relief and improved function, have been outstanding. Problems of infection, loosening and fracture of adjacent bone have been less than with other intrinsically stable prostheses (hinge prostheses) and are less than most reports of non-articulated resurfacing prostheses followed for a comparable time. There have been no failures within the prosthesis. Our loose prostheses represent failures that occurred between the prostheses and the bone. The spherocentric prosthesis is the prosthesis of choice for arthroplasty of a knee with severe preoperative deformity or severe instability or both in which optimal results would not be anticipated following insertion of a resurfacing type of prosthesis.


Reconstruction with endoprosthesis in gonarthrosis: a report of 111 consecutive cases operated upon from 1973 through 1977. The results of reconstruction with 3 standard knee joint endoprostheses in advanced gonarthrosis are reported prospectively for 111 consecutive cases operated upon during the years 1973 through 1977 according to a consecutive, precise routine. High tibial osteotomy was indicated in the early stages of the disease, i.e., roentgenographic Grades I and II. In advanced gonarthrosis constituting Grades III to V, unicompartmental reconstruction with hemiprosthesis was performed in 68% of the cases, while 26% needed a stablizing total surface prosthesis and 6% a hinge prosthesis. This differentiation is important in view of the better results achieved in the category of hemiprosthetic reconstructions compared with those of the 2 latter categories. In the total series, 96% of the patients were satisfied or improved correlating with the clinical assessments made at regular clinical and roentgenological examinations 1 to 5 years after the operation; there were 99% in the hemiprosthetic group and 93% in the group having total surface replacement. In the former group of patients, wear of the tibial component was detected in 3%, while loosening occurred in 6 and 11%, respectively. The rates of primary deep infection were 1 and 3%, respectively, and, in addition, 7% (3 cases) in the latter group showed the occurrence of late deep infection. Relief of pain, correction of deformity and a range of movement of 90 degrees or more, were the most significant results. Strict indications and operative techniques should be used according to the different stages of gonarthrosis.


Pseduarthrosis of a tibial plateau fracture: report of a case. In an elderly woman a tibial condylar pseudarthrosis was angulated with disabling pain, significant deformity, and progressive articular deterioration. The treatment of this non-union consisted of arthrotomy, mobilization of the ununited medial condyle, slight over-elevation of the tibial plateau, iliac bone grafting to reconstitute loci of bone loss, and rigid interfragmentary and buttress plate fixation. Postoperative management consisted of early knee motion and delayed weight-bearing to facilitate functional restoration of the extremity. Within 3 months, union occurred in anatomic position.


Fracutres of the proximal tibia and tibial condyles: a clinical and laboratory comparative study. Angulatory deformities frequently develop following condylar and proximal diaphyseal tibial fractures. Laboratory studies conducted in cadaver specimens with artificially created fractures closely resembled the behavior of fractures treated with functional braces. Providing that the fibula factor is properly assessed, selected condylar and proximal tibial shaft fractures can be successfully treated by nonsurgical means including early knee motion in a brace followed by graduated weight-bearing ambulation.


Reconstruction of the knee with endoprosthesis in rheumatoid arthritis: a report of 112 consecutive cases operated upon from 1973 through 1977. In a consecutive series of patients with advanced, seropositive rheumatoid arthritis, 112 severely damaged knees were reconstructed with a stabilizing, total resurfacing prosthesis in 80%, a hemiprosthesis in 13% (3% biocompartmental) and a hinge prosthesis in 7%. Eighty per cent of patients receiving the resurfacing prosthesis were satisfied and, in addition, 8% improved at prospective follow-up examinations one to 5 years postoperatively. The subjective results showed good correspondance with the clinical and roentgenologic assessments. The joints reconstructed with the total resurfacing prosthesis were free from effusion or any inflammatory activity in 96%, stable in 88%, and showed full correction of deformity in 84% while 16% showed a fixed flexion of 10 degrees up to 20 degrees. Walking ability with regard to the need for walking aids was considerably improved. So far, 2% of the knees have had the prosthesis removed and a fusion performed; one per cent because of primary deep infection and the other one per cent because of late deep infection. Four per cent of the cases have shown loosening of the tibial component, necessitating reoperation.


Experience with 141 tibial lengthenings in poliomyelitis and comparison of 3 different methods. Three different distraction devices were investigated for the treatment of leg-length discrepancy caused by poliomyelitis in 144 patients. The average leg-length discrepancy was 5.2 cm and lengthening obtained 4.8 cm. For tibial leg-lengthening. Anderson's apparatus was used in 50 patients; an external fixator device (developed in Shafa Rehabilitation Hospital) was used in 40 patients; and the Wagner apparatus was used in 51 patients. The incidence of major complications was low in all 3 groups. The overall failure rate was 4%. There were no significant differences in the final results among the 3 groups. However, preference is given to the Wagner device because of its practical advantages.


Tibial torsion--a simple clinical apparatus for its measurement and its application to a normal adult population. A new simple goniometric device, designed for the measurement of tibial torsion provides simple and reliable means of quantitating tibial torsion. Data comparing values obtained by this apparatus are comparable to values obtained by roentgenographic methods.


Synovial osteochondromatosis in association with Legg-Calvé-Perthes disease. A male patient who had had Legg-Calvé-Perthes disease at age 8 years developed synovial osteochondromatosis of the same hip joint 27 years later at age 35. Roentgenographic examination 10 years prior to arthrotomy showed that he had developed 4 loose bodies in the hip and partial disintigration of the fmoral head. The surgical specimens obtained by arthrotomy consisted of 148 loose bodies and suggested that a condition of secondary synovial osteochondromatosis might be differentiated from primary synovial osteochondromatosis.


Sacral agenesis with associated anomalies (caudal regression syndrome): autopsy case report. Autopsy findings of an infant with sacral agenesis and multiple anomalies of the lower half of the body which fit the description of the caudal regression syndrome are reported. The lumbosacral plexus of nerves was more abundant on one side despite symmetrical lumbar vertebral dysgenesis with agenesis below S1. The presence of intrathecal kidney tissue has not been previously reported in this syndrome. Diethylopropion hydrochloride, an appetite supressant, which was ingested by the patient's mother during the first month of pregnancy, was cited as a possible etiologic agent.


Intramedullary pressure patterns.

Intramedullary pressure patterns. The insertion of cement and femoral prosthesis in total hip replacement produces biochemical abnormalities. These are thought to be caused by a marked rise in intramedullary pressure. Surgeons aim to reduce these pressures by using different methods of insertion and venting. The present investigation was undertaken to establish if any one method was superior to the others. The greatest modification of acrylic pressure was obtained by means of a drill hole. Thie highest rise in pressure was produced by the insertion of the femoral prosthesis and this was little modified by any of the alternatives of the use of a 3/16 inch drill hole, a 16-gauge catheter, and cement gun.


Bipartite trapezium with adduction contracture of the thumb: a case report. This is a case report on bipartite trapezium in a 12-year-old girl that presented as a painless protrusion at the base of the first metacarpal bone associated with an adduction contracture of the thumb. This seems to be the first such case to have been reported in an adolescent. The condition bears no resemblance to the numerous descriptions in the literature on accessory bones about the trapezium.


Surgical morbidity in patients with neurologic dysfunction. Mortality and morbidity data were collected on 388 patients treated by operations to correct extremity deformities caused by stroke, head trauma and neurologic disease. A total of 613 procedures were performed, requiring 524 general, 2 spinal and 16 regional anesthesias. There were no postoperative deaths. None of the patients showed further neurologic deterioration. The incidence of medical complications was 6.4% and all patients responded to medical treatment. Sixteen wound complications responded to routine care. Age appeared to be the primary risk factor to postoperative morbidity. It is generally safe to perform elective orthopedic surgery to correct extremity deformities in the neurologically involved patient.


Compression arthrodesis of finger joints. Compression arthrodesis is useful for treatment of finger and thumb joints in arthrosis, scleroderma, hypermobile joints, paralytic deformities, and rheumatoid arthritis. A dorsal incision exposes the joint. Its surfaces are prepared in a ball-and-socket arrangement using a high-speed burr. A longitudinal pin 1.1 mm in diameter is passed distally and then retrograde to determine the angle of fusion and to prevent migration of bone ends as the longitudinal compression is applied. Transverse pins 1.5 mm in diameter are put in one-third of the distance from the joint. A Charnley clamp, as modified by Micks and Hager, is applied and tightened. At 6 weeks, the arthrodesis is checked for solidity and, if stable, X-rays are examined for new bone. When solid, the joints should be protected by external splinting for an additional 2 weeks to be sure that the fusion is complete. Compression arthrodesis was obtained in 49 of 54 joints. Solid fusion was usually attained within 6 weeks, without loss of mobility of other joints.


Septicemia following sinogram.

Septicemia following sinogram. Contrast studies of draining sinus tracts can be of great assistance in defining the extent of an infection. Complications of this procedure must be quite rare. A 35-year-old paraplegic patient developed septicemia following a sinogram. An intraosseous venogram of the entire femoral shaft was visualized in addition to the sinus tract itself. The moderate pressure used to inject the dye may have contributed to the systemic spread of the infection and may be a hazard of sinography.


Renal cell carcinoma presenting as a skeletal muscle mass: a case report. A 62-year-old man presented with a 17-month history of a slowly enlarging biceps muscle mass. A diagnosis of metastatic renal cell carcinoma was made in the outpatient department using a soft tissue biopsy needle. Despite the rarity of muscular metastases in renal cell carcinoma, early definitive diagnosis of soft tissue masses is recommended.


Polycentric total knee arthroplasty: a prognostic assessment. Polycentric total knee arthroplasty has been performed at the Mayo Clinic on more than 1,600 knees since July 1970. Two groups of 106 and 101 knee arthroplasties performed between July 1970 and July 1971 and June 1971 and January 1972, respectively, were compared at 5 and 7 years. The technique used exposed the joint to methacrylate particles, yet, despite this, wear did not prove to be a problem. Failures occurred because of infection, loosening of the tibial components, settling of the tibial components, subluxation or dislocation, ligamentous laxity, progression of patellofemoral arthritis, and persistence of pain. We did not encounter patellar problems in our patients with osteoarthritis. In the first group with 106 knees, 45 patients with 58 rheumatoid knees survived 7 years; 79% of knees had good results at 5 years and 72% had good results at 7 years. Twenty-one patients with 28 osteoarthritic knees survived 7 years; 75% of knees had good results at 5 years and 61% had good results at 7 years. In group 2 with 101 knees, 43 patients with 64 rheumatoid knees survived 7 years. The results were good in 83% at 5 years and in 64% at 7 years. Among the 20 patients with osteoarthritic knees who survived 7 years, 92% of knees had good results at 5 years and 62.5% had good results at 7 years. This figure is somewhat misleading because 7 patients were lost to follow up in group 2 after 5 years. There is still a need for a well-tolerated resurfacing procedure by means of a nonconstrained prosthesis.


Metatarsus primus varus: including various clinicoradiologic feautres of the female foot. Metatarsus primus varus occurs in feet which have a normal 1--2 intermetatarsal angle. Fifty-two Caucasian females, average age 18 years, were analyzed radiologically for 1--2 and 1--5 intermetatarsal angles and for metatarsophalangeal and first interphalangeal joint angles. Measurement of the 1--5 rather than the 1--2 intermetatarsal angel is a more reliable indicator of first metatarsal varus. Valgus at the first interphalangeal joint is normally greater than that at the first metatarsophalangeal joint and excessive first interphalangeal valgus (valgus interphalangeus) is significantly linked with the presence of ossia tibiale externa. The high arch foot tends either to feature valgus interphalangeus or become excessively broad. The anatomy of the ungual tuberosity is highly variable.


Factors contributing to lysis of the femoral neck in total hip arthroplasty. A radiographic analysis of 483 Charnley total hip arthroplasties performed from July 1970 to November 1975 demonstrated that 13% of the hips had lysis of the medial femoral neck. The findings suggest that the lysis of the medial femoral neck is significantly reduced if the femoral stem is oriented in a valgus or neutral position and with at least 5 mm of cement separating the stem of the prosthesis and the medial cortex of the femoral neck.


Does persistent fetal femoral anteversion contribute to osteoarthritis?: a preliminary report. Persistence of femoral anteversion into adulthood is a developmental abnormality which Somerville has postulated may predispose to the later development of osteoarthritis of the hip. To test this hypothesis, the femoral anteversion was measured in 20 adult patients with idiopathic osteoarthritis of the hip. The average anteversion in painful hips was found to be 24 degrees compared with 12.11 degrees in the uninvolved hip. None of the pain-free hips had an anteversion of greater than 22 degrees while 54% of those with pain had anteversion greater than this value. While these results are preliminary, they suggest that increased femoral anteversion may definitely contribute to the later development of osteoarthritis of hip.


Barrier to material transfer at the bone-cartilage interface: measurement with hydrogen gas in vivo. Hydrogen gas was used as a tracer to identify the barrier to material transfer at bone-cartilage interface in the rabbit knees in vivo. The transfer of hydrogen molecules from subchondral bone to articular cartilage was detected by means of platinum electrodes which were placed in varying depths in articular cartilage and subchondral bone. Hydrogen transfer was obstructed at the osteochondral junction in mature animals, while in immature animals there was no such barrier present in the bone-cartilage interface. The metabolism of articular cartilage in mature animals may be isolated from that of the underlying bone. All layers of the mature cartilage including those in the zone of calcified cartilage can receive nourishment and be maintained from the synovial fluid alone.


The mechanical strength of the growth plate under the influence of sex hormones. As sex hormones are considered to play a role in the etiology of the slipped upper femoral epiphysis, the influence of sex hormones on the mechanical strength of the epiphyseal plate was investigated in 310 female and 70 male rats. Ovariectomy weakened the strength of the growth plate while orchiectomy strengthened it. Estrogen given after ovariectomy, markedly strengthened the plate. Histologic examination revealed that the width of the growth plate was narrower in the mechanically stronger group. Hydroxyproline content increased and hexosamine content decreased in the epiphyseal plates of the mechanically stronger group. These observations confirm the view that sex hormones, especially estrogen, regulate the mechanical, morphologic, and biochemical functions of the growth plate.


The effects of barium sulfate on the polymerization temperature and shear strength of surgical simplex P. Barium sulfate additive, in amounts ranging from 5% to 60%, causes a progressive reduction in polymerization temperature of the cement without appreciably altering the polymerization time. Concurrently, the mechanical strength of the cement, as determined in shear, decreases with increasing concentration of barium additive. Although inclusion of barium sulfate in acrylic bone cement is primarily used for radiographic contrast purposes, its possible effects on release of monomer and other local mechanisms seem not to have been measured.


An in vitro study of electrical osteogenesis using direct and pulsating currents. Although many investigators have electrically stimulated osteogenesis in vivo, this phenomenon has not been reported in vitro. In this work direct and pulsating currents were applied to in vitro fetal rat tibiae. The results indicated that electric current did cause osteogenesis in vitro, precipitates of calcium compounds formed in the cathode region, and direct current was more effective in stimulating bone growth than pulsed current delivering the same total charge (coulombs).


Intramuscular pressure during walking: an experimental study using the wick catheter technique. Experimental studies have shown previously that intramuscular pressure is directly related to muscle tension. A wick catheter study of intramuscular pressure in the human tibialis anterior was performed to investigate dynamic changes in walking and in other selected activities. In walking, peak intramuscular pressure of 50 mm Hg occurred in the swing phase as the foot was lifted and continued in early stance phase during deceleration of the foot. Passive stretching of the tibialis anterior muscle produced an increase to 35 mm Hg with no EMG activity. Active contraction against heavy resistance produced a rise in intramuscular pressure to 107 mm Hg. In contrast to electromyography, intramuscular pressure represents both the active and passive components of muscle tension.


Two-part total knee arthroplasty: evolution and present status. The inception of a 2-part total knee arthroplasty consisting of a Vitallium femoral component and a polyethylene tibial component occurred in 1970. It was termed "geometric," because it was not anatomic in design. This geometric design was altered during the ensuing years to allow better fixation of the tibial unit, because loosening of this unit became apparent in an appreciable percentage of patients. As biomechanical research and clinical evidence progressed, less need for the constraint built into the geometric prosthesis became evident. So a less constrained, more anatomic total knee, called the "anametric" total knee arthroplasty, was developed. There was duplication of the normal anatomic configuration of the femoral component for both left and right sides, a femoral flange so that the patella could be surfaced with polyethylene, and a flatter surface for the tibial unit. The tibial unit was first anchored with the geomatric triflanged system, but eventually comprised a medullary stem and a metal T-tray to contain the polyethylene. At this time, we believe that sufficient constraint necessary in the usual total knee arthroplasty is realized with the anametric design. The anametric design has proved itself and is now our prosthesis of choice.


On the origins of high in vivo wear rates in polyethylene components of total joint prostheses. Scanning electron microscope examination of the polyethylene components of 8 total hip and 16 total knee prostheses which had been implanted 4--96 months revealed that in many cases severe wear may not necessarily be caused by the presence of acrylic cement debris or other abrasives. The craters and cracks observed on severely worn surfaces are associated with fusion defects in the plastic itself. The fusion defects were seen to occur as a result of the low temperature necessary to mold ultrahigh molecular weight polyethylene and are (at least at present) difficult to avoid. As a consequence of the above and variability of molecular weight in this material, relatively wide variations in wear rate should be expected even in the absence of acrylic debris.


ICLH replacement of the knee: 1977 and 1978. Investigations which began in 1968 have culminated in a knee arthroplasty which can now be confidently used to treat most patients with arthritic knee deformities. Our earlier studies showed that a prosthetic knee arthroplasty must be reliably aligned and stabilized in extension, that patellar pain and polyethelene wear were significant potential problems and that loosening and sinkage of the tibial component must be avoided. Our present knee prosthesis and instrumentation if properly used should avoid these pitfalls. Beginning in January 1977 we performed 84 knee arthroplasties utilizing the present design. A series of 79 knees has been available for our computer-assisted review; 46 patients had a diagnosis of inflammatory arthritis and 29 had primary osteoarthrosis: 22 knees had been previously operated upon. Although all femoral components were fixed with polymethylmethacrylate, the tibial components were completely cemented in 21 knees, partially cemented in 20, and no cement was used in 38 cases. In these latter knees special pegs provided a mechanical interlock with the tibia for fixation. Thirty-six patellae were replaced, of which 11 were fixed with a similar interlocking peg. The arthroplasties failed in 8 patients. Of the remainder, 90% of knees had acceptable pain relief and all but 4 patients were able to walk outdoors. Flexion to 90 degrees or more was achieved in 85% of the knees. Only 2 patients had unacceptable alignment. To date we feel that with the use of this improved prosthesis, in conjunction with the instruments which allow proper placement of the prosthesis, the majority of arthritic knees can be successfully corrected. However, further careful long-term follow-up studies must continue.


Total knee replacement with the Kodama-Yamamoto knee prosthesis. Since 1970, 170 knees have been operated upon using the Kodama-Yamamoto knee prosthesis. Of these 127 had the revised Mark-II prosthesis and of this group 91 cases have been followed for more than a year. Interim results suggest that the total knee score has improved. on the average, from 38 points preoperatively to 74 points after one year. A single early complication involved loosening of the prosthesis in a case of knee infection. Except for this case, no loosening and no radiolucent lines have been observed. Methacrylate bone cement is known to be harmful to bone and soft tissues, and our basic and clinical studies reveal that results improve when the total knee replacement is done without using cement.


The total condylar knee prosthesis: the first 5 years. The total condylar knee prosthesis evolved from previous experience with other prostheses at the Hospital for Special Surgery. This evolution includes patellar resurfacing. Subsequent modifications have led to the total condylar knee prosthesis II (a cruciate substituting prosthesis), and the total condylar knee prosthesis III (a TCP II with increased constraint). The surgical technique requires ligamentous balance with correction of preoperative deformity by a soft-tissue release. Subsequently a standard operation is performed. Four hundred and sixty-one knees were reviewed with a minimum of one year follow-up and a maximum of 5 years. Seventy-five per cent were osteoarthritic knees. Using the Hospital for Special Surgery Knee Rating Scale, the results were excellent in 312 knees (68%), good in 109 knees (23.5%), fair in 18 knees (4%) and poor in 22 knees (4.5%). Osteoarthritic knees (excellent or good 93.5%) did slightly better than rheumatoid knees (excellent or good 87%). Complications include 6 infections, 6 subluxations and 10 cases of component loosening. There were 15 reoperations (3%). The results approach total hip arthroplasty in quality and so far have not deteriorated with time.


Total knee arthroplasty experience at the Robert Breck Brigham Hospital. Between 1973 and 1978, 1,474 metal-to-plastic knee arthroplasties were evaluated to determine the typical modes of failure and improved design concepts (Table 2). Although the concepts are still evolving, and longer follow-up is necessary, recent experience with nearly 1,000 semiconstrained devices allowing cruciate retention strongly suggests that duopatella and kinematic design concepts are correct. Soft tissue reconstruction is critical with these designs, since they rely heavily on soft tissue integrity and balance. If the concepts of soft tissue balance, prosthetic design, and physical rehabilitation are applied, total knee replacement is as reliable in relieving pain and restoring function as total hip replacement. The low incidence of radiolucency at the bone-cement interface (although the length of follow-up is relatively short), coupled with the results of in vitro bench testing, suggest that the longevity of this generation of knee implants should be adequate.


A prospective comparative clinical analysis of the first-generation knee replacements: polycentric vs. geometric knee arthroplasty. A prospective study of 119 polycentric and 92 geometric knee replacements was performed to determine and compare the clinical effectiveness of these two prostheses. All kneex were followed for a minimum of 2 years and a mean time of 3 1/2 years (2--6 years). Data were collected using a specially designed proforma for subsequent computer analysis. Failure occurred in 11% of the polycentric and in 16% of the geometric knees. Males (8 of 47) and patients with osteoarthritic knees (22 of 68) failed most frequently. Both prostheses provided excellent relief of pain, the same degree of flexion and improvement in flexion contracture. However, walking, function, alignment, stability, muscle strength and patellar mobility varied as to the degree of improvement and the type of prosthesis. Present results with prosthetic knee replacement using a completely new operative technique can be used as a basis for comparison with other contemporary and future arthroplasty designs.


Current status of a hinge prosthesis (GUEPAR). Although a great many GUEPAR hinge knee prostheses have been successful, the early complications have been numerous. Also, long-term follow up studies have been hampered owing to the patients' advanced age. Many of the patients died of causes unrelated to their knee. The use of this prosthesis is limited to very old patients or individuals with grossly dislocated knees. Previous problems such as patellar pain have been resolved. Because the femoral and tibial stems have been reinforced, they are much stronger and cement is no longer necessary for fixation. The part that articulates with the patella has been changed so that it is now more shallow and better adapted to the shape of the patella.


Anametric total knee arthroplasty.

Anametric total knee arthroplasty. The early experience with the anametric knee prosthesis shows it to be effective in achieving the aims desired in total knee arthroplasty. Decreased pain and improved function have been noted in most patients, with relatively few complications. In osteoarthritics, patellar replacement increases the level of improvement. This prosthetic system has been improved by the addition of further sizes and additional tibial fixation options. Detailed long-term follow-up evaluation of these patients will be necessary to judge the effectiveness of the newly introduced design modifications.


The "caviar" madreporic knee prosthesis. The madreporic ("caviar") prosthesis is a hinged knee prosthesis that can be inserted without the use of cement. The surfaces of the intramedullary stems are constructed with contiguous spheres one mm in diameter. These spaces are filled by bone trabeculae and haversian bone, providing permanent biologic fixation. Experimental madreporic knee arthroplasties in dogs show that bone probes these surfaces and produces solid attachments. Histologically, the trabeculae remain separated from the metal by a fine layer of fibrous tissue. The method of insertion of the prosthesis is simple. Preparing the epiphyses before any bone resection avoids the possibility of rotational positioning errors. The form of the intramedullary stems offers good positioning in the frontal plane. The analysis of an initial series of 15 cases shows results that are far from outstanding. The 2 deaths, the 2 cases of sepsis, and the recuperation of only mediocre motion can be explained, at least in part, by the advanced age of the patients and the poor bone quality of the rheumatoid patients. Nevertheless, this type of prosthesis has 2 important advantages. It avoids the complications from the use of acrylic cement and allows for a revision operation for cases of failed surface replacement designs. Obviously further experimentation with noncemented designs will continue and definitive studies will be reported later.


The Coulter Counter Model S Plus--the shape of things to come. The Coulter Counter Model S Plus is a 12 parameter haematological analyser designed for service use in haematology laboratories. Eight parameters are standard in current routine haematological practice; the seven parameters generated by the Model S and a platelet count. The method of platelet counting is unique. The remaining parameters are new and comprise the platelet-crit, the mean platelet volume and size distribution measurements for both platelets and red cells. A description of the instrument is given including differences from the Model S. The new parameters are discussed in detail. Instrument precision is assessed in terms of linearity, reproducibility, drift, carry-over and protein build-up. The results of all are impressive. Instrument accuracy is assessed in detail; white cell count, red cell count, haemoglobin concentration and mean corpuscular volume being compared with those values measured by the Model S; the Model S Plus haematocrit is compared with the microhaematocrit and platelet counts with those from the Thrombocounter C/Thrombofuge system. All correlations are very satisfactory. Normal values are defined for the new parameters. Instrument design and function are assessed and reagent consumption quoted. Cell control reagents have been evaluated. A realistic hourly throughput for the Model S Plus is 70-80 samples.


Home treatment in haemophilia: clinical, social and economic advantages. Twenty-eight severely affected haemophiliacs were observed for 3 months under treatment as hospital out-patients and for the subsequent 9 months while treating themselves at home. Delay in receiving treatment and financial costs were both clearly reduced by home treatment, the patients recovered from individual bleeds more quickly and reported a greater sense of personal freedom and independence. The amount of treatment required did not materially change and no untoward effects were noted; the use of analgesics tended to be less.


A comparison of methods for analysing red cell and platelet volume-distribution curves. Cell volume-distribution curves may be analysed using log-probability paper or by considering volumes corresponding to frequencies of 50 or 60% of that at the mode. All methods give similar results; the log-probability paper method is better because it allows the researcher to check that the underlying distribution is lognormal; methods based on 50 or 60% modal frequency are slightly less reliable but are simpler for routine use. For platelets it may be convenient to estimate the curve from the modal volume and the volume above the mode at which the frequency is reduced to 60% of the modal frequency.


Anti-Cad lectin from the seeds of Leonurus cardiaca. A predominantly Cad-specific lectin is present in the seeds of Leonurus cardiaca. Extracts of these seeds makes a valuable addition to reagents used in the elucidation of red cell polyagglutinability.


Draft protocol for testing calibration and quality control material used with automatic blood-counting apparatus. A large number of commercial preparations are now available for calibrating or checking the stability of automatic blood counters. Most of these preparations are supplied with 'stated' values though the methods for assigning these values are not described in sufficient detail to allow for an adequate assessment of the validity. The Haemocytometry Panel of the British Committee for Standards in Haematology are therefore proposing a draft protocol for testing calibration and quality control materials. Comments on the draft protocol are invited, either as letters to the Editor of Clinical and Laboratory Haematology or in confidence to the Chairman of the Haemocytometry Panel.


A commercially available interactive pattern recognition system for the characterization of blood cells: description of the system, extraction and evaluation of simple geometrical parameters of normal white cells. A programmable system, the Textur Analyse System (T.A.S.) of E. Leitz, is described for use in interactive work on pattern recognition of white blood cells. The system appears well suited for the task of finding new parameters for the characterization of normal and abnormal blood cells. Hardware advantages such as speed of operation are coupled with software flexibility. The first application of the machine has been the extraction of some of the ordinary parameters for characterization of leucocytes. The value of each parameter has been analysed with the interactive statistical pattern analysis program (ISPAHAN). A separation in the five normal classes of peripheral white blood cells can be achieved, in which the nuclear/cell area ratio and nuclear area together with the density histograms proved to be the most important parameters. The interesting feature of the system is, however, the possibility of finding new data for the recognition of normal and abnormal blood cells.


Assessment of the Coag-a-Pet Dual Channel in the routine haemostatic laboratory. The Coag-a-Pet Dual Channel is an instrument which automatically records coagulation test end-points utilizing a photo-optical clot detection system. The instrument and its operation are described in detail. The capability of the instrument to perform tests of oral anticoagulant control, basic coagulation profiles and one-stage factor assays is assessed. In terms of precision and accuracy, the instrument performs well in carrying out the one-stage prothrombin time, Thrombotest, activated partial thromboplastin time using an automated APTT reagent but not kaolin, and one-stage factor assays. The thrombin clotting time can not be measured on this instrument. The instrument is most suitable for batched repetitive tests, reducing observer error and improving laboratory efficiency.


A minicomputer laboratory data-management system: the St. Mary's system and its haematology applications. The computer system developed at St Mary's Hospital Medical School, and now used in six hospital haematology laboratories, is described. The system allows for the rapid retrieval of pathology results from an archive of at least 180 000 records on a 10 megabyte disk. Two main data files are used, the "Current File", from which reports are prepared, and an "Archive File" which contains cumulated results. The files are indexed by parts of both the name and, if available, the hospital number. Patient linkage is accomplished using the whole known identification, but, unlike most other systems, no absolute requirement is placed on the existence of a hospital number. It is concluded that this method of patient linkage removes many of the management overheads associated with hospital number linked systems, and that use of the computer not only aids reporting, but also improves quality control and provides data for research.


The course and complications of idiopathic erythrocytosis. The presenting features, haematological and clinical course of 30 patients with unexplained high venous haematocrit have been analysed. At presentation these patients had definite polycythaemia, but lacked other features which would permit their classification as primary proliferative polycythaemia (PPP). In the follow-up period, twelve patients (40%) developed features within 6 years of diagnosis which allowed them to be reclassified as PPP. It is suggested that, because of this transition, the term idiopathic erythrocytosis is a more suitable initial description of this group than, for example, benign erythrocytosis. The high incidence of vascular complications at presentation, and the fact that a cerebrovascular accident was responsible for the death of five out of the seven patients who have so far died, is discussed and compared with similar events in PPP. The existence of a pure line red cell proliferation cannot be confirmed or excluded by the observations in the present group of patients. The findings do indicate that follow-up and observation of such patients may establish causes for polycythaemia not in evidence or considered at presentation.


Diagnosis of bone marrow necrosis.

Diagnosis of bone marrow necrosis. Two cases of bone marrow necrosis (BMN) were diagnosed during life. Both patients developed BMN as a terminal event in the evolution of untreated malignant lymphoma. No earlier cases of BMN in untreated malignant lymphoma are reported in the literature. In one patient necrotic and normal bone marrow were simultaneously obtained from two different aspiration sites, showing the focal nature of the process. BMN itself being reversible, the diagnosis in vivo is important. A better knowledge of the significance of a yellow brown viscous fluid obtained by bone marrow aspiration and the exact interpretation of necrotic bone marrow films are essential to recognition of BMN.


Platelet counting-development of a reference method and a reference preparation. A reference method has been defined for platelet counting by counting chamber haemocytometry, and a procedure has been developed, using platelet rich plasma (PRP) and a Coulter ZBI counter which provides a reliable, rapid and relatively simple method for platelet counting which is closely comparable to the reference method and can thus be used both as a secondary reference method and a routine method. The optimal method for obtaining PRP from EDTA blood was by augmented sedimentation with Boyum's methyl cellulose-metrizoate mixture at sp. gr. 1.08. This was shown to yield a platelet suspension which reflects closely the platelet content of the original blood. Calibration of electronic counters for platelet counting requires material which is stable and which parallels natural human platelets in size, distribution and other physical characteristics. A suspension of glutaraldehyde-fixed human platelets in glycerol appears to be suitable as a reference preparation. Its method of production is described.


Governing board and management staff attitudes toward community mental health center citizen participation. The present study investigated the attitudes and values of community and mental health center board and management staff of four Community Mental Health Centers and one mental health clinic toward the recent federal mandate calling for increased citizen involvement in center evaluation activities. Three related areas were address: (a) general attitudes toward citizen participation, (b) types of program-evaluation activities in which citizen input would be most useful; and (c) types of individuals who would best serve on citizen review groups. The results indicated that although board members are somewhat more optimistic about benefits received from citizen involvement, overall there was close agreement between the board and staff respondents in the three areas studied. These results were interpreted as substantiating the view that community mental health center boards typically reflect a provider orientation in their approach to mental health governance. A missing evaluation component in most centers is citizen participation as it reflects the values of its service consumers. It is advocated that only by developing consumer participation mechanisms will centers more readily achieve the goal of responsiveness to community needs.


Support systems and mental illness in the elderly. Clinical experience indicates an especially important role for support systems in a bio-psychosocial approach to understanding the development of mental illness in elderly persons and the provision of appropriate services for them. Family, work, and community supports are reviewed. The authors believe optimistically that the present traditional supports are not worse than those of the past and that new models exist for future use. In addition, the anticipated increased numbers of elderly make it important that clinicians be well informed and plan multifaceted responses and that community mental health centers, as service and support systems actually in place in many underserved areas, take advantage of multiple available funding streams to increase substantially their assistance for the elderly.


Euthanasia: a serene voyage to death?

Euthanasia: a serene voyage to death? Modern Western Culture regards death as a threatening enemy, whereas the ancients, as is the case in eastern philosophy, recognized both the fight with, and the releasing surrender to death. Dying is quite often a serene voyage, be it through old age, sickness, was or even suicide. Attentive listening to those who face the termination of incurable disease reveals the voice of enlightenment: 'euthanasia' also means 'clarified dying'. An attitude like this alleviates our recoil and assists in a supportive approach to the dying human.


[Creativity in adolescence].

[Creativity in adolescence]. The phenomen of transitory artistic creativity in adolescence is discussed. Although adolescents have the same qualities as adults their artistic productivity varies. Various concepts of creativity as found in the literature are discussed, especially those comparing adult and adolescent personality. The different developmental stages of adolescence correspond to different stages of creativity which are the products of various ego stages and ego defense mechanisms during the three adolescent periods.


[Catamnestic observations regarding the case of an obsession. Demoniac obsession nowadays]. A report is given on the catamnesis of a 43-year-old, previously obsessed female person whose case history was in detail described and discussed in this journal [14: 203-225 (1971)]. Following the attempt of an interpretation of this clinically rare case, testified in its time, the phenomenon of the obsession was discussed in the light of psychiatry and theology at the present time, when man is haunted by fear for his existence and obviously has recourse again to exorcism.


A-nor steroids as post-coital contraceptives in the hamster with special reference to the transport and degeneration of eggs. Two A-nor steroids, Anordrin and H241, showed a marked antifertility effect when given orally to hamsters at 10 mg/kg/day for three or four days after mating. Further study indicated that the antifertility effect was due to a disturbance of egg transport, retarded development and degeneration of fertilized eggs.


Effects of 17 beta-hydroxy-7 alpha-methylandrost-5-en-3-one (RMI 12,936) on pregnant rabbits. A single subcutaneous injection of RMI 12,936 interrupted 8- and 15-day pregnancy in the rabbit. A dose dependent loss of embryos was observed. Higher doses of RMI 12,936 were needed to terminate pregnancy in 8-day pregnant (74% efficacy with 10 mg/kg) than in 15-day pregnant rabbits (100% efficacy with 8 mg/kg). Termination of pregnancy by RMI 12,936 was accompanied by a significant increase of progesterone (delta 4 p) in rabbits receiving 10 mg/kg RMI 12,936 on day 8 of pregnancy. On the other hand, treatment with 8 mg/kg RMI 12,936 on day 15 of pregnancy did not alter the delta 4 p levels, but induced a significant decrease in 20 alpha-dihydroprogesterone. In these two treatment groups, a consistent and highly significant increase of serum testosterone (T) was observed. The increase of T value possibly was due to a decrease in aromatizing ability of the follicles after RMI 12, 936 treatment and might have contributed towards the interruption of pregnancy. The failure of RMI 12,936-treated rabbits to ovulate even after hCG administration suggests that his compound might have lowered the sensitivity of the mature follicles to LH stimulation.


Isolation of Yersinia enterocolitica and Yersinia pseudotuberculosis from human specimens and their drug-resistance in the Niigata District of Japan. A total number of 60 Yersina strains (Yersinia enterocolitica 58; Yersinia pseudotuberculosis 2) were isolated from 58 patients who were more or less doubtful to yersinia infection in the Niigata district. An etiologic significance with respect to serogroup and biovar was investigated from the following viewpoints, (1) serum agglutinin titer; (2) positive recovery in the follow-up; (3) relation of positive specimen to the inflammatory lesion, (4) comparison with the isolates from a healthy group. Thus, etiologic significance was highly susceptible in the cases with 03 (4), 03 (3), and 05B (2) of Y. enterocolitica and Y. pseudotuberculosis, less susceptible in those with 05A (1) and 015 (1) of Y. enterocolitica and not susceptible in those with 06 (1), 07,8 (1), and 012 (1) or Y. enterocolitica. Among the isolates, drug-resistant strains--some of them involved with R plasmid--were demonstrated.


Investigations of source and route of Yersinia enterocolitica infection. Isolation of Yersinia enterocolitica was performed on healthy humans, animals and food, and growth of Y. enterocolitica on sliced ham at various temperature ranges was also examined. It was noticed that the most prevalent 0 group (03) in human infection was isolated from swine, pork and chopping boards. The storage of food in the refrigerator (5 degrees C) possibly increases the risk of infection since Y. enterocolitica is multipliable at low temperatures more readily than many other pathogenic bacteria. Pork and meat products contaminated with Y. enterocolitica, either primarily or secondarily, are probably the most important source of human infection.


Comments on the ecology and epidemiology of Yersinia enterocolitica in Czechoslovakia. On the basis of the information disseminated by the Reference Laboratory in 1968, the microbiological diagnosis of Yersinia enterocolitica (Ye) was gradually mastered by all Czechoslovak microbiological laboratories. The most frequent serotype isolated in man was Ye 03. Isolation predominated from cases of diarrhoea, less often from appendectomies, and only one case of septicaemia was described. Usually only sporadic cases occur and outbreaks are rare. A few strains of Ye 05 were found in diarrhoeas. Epidemiological analysis of Ye diarrhoeas showed that infections due to Ye 03 occurred prevalently in small children in large cities; infected people were only rarely in direct contact with pigs or other domestic animals suspected as possible vectors. One interhuman transfer (two young children in one family, incubation period 7 days) was observed. Ye 03 was isolated only from man, pig, dog, cat and rats from pig houses; on the other hand, in wildlife, water (drinking and surface water) and foodstuffs other Ye serotypes, and mostly biotype 1, are found.


Canadian experience with Yersinia enterocolitica (1966--1977). Data pertaining to 1,219 cultures of Yersinia enterocolitica isolated in Canada are summarized. Of the 977 cultures isolated from humans, Y. enterocolitica serotype 0:3, biotype 4, phage type IXb was the most predominant type in Ontario, Quebec and the four Eastern Provinces. In the Western Provinces the predominant strains were indol-positive, serotypes 0:8; 5,27 and 4,32. Most of the 242 cultures of nonhuman origin, except those isolated from swine and a few isolated from wild animals, were indol-positive, biochemically atypical and serologically nontypable or belonging to different serotypes which have seldom been found in human infections.


Epidemiological and clinical aspects of human Yersinia enterocolitica infections in Belgium. In the period from 1963 to 1975 data were collected on 1,781 isolates of Y. enterocolitica from human infections in Belgium. There was an uneven spread of the cases over the country, but this could simply reflect the distribution and activity of medical laboratories. Serotype 3 dominated (89.2%) followed by serotype 9 (8.6%). Less than 1% of all isolates were from nonenteral sources. Gastroenteritis was the diagnosis in 86.8% of patients, while 10.6% were suffering from an appendicitis-like syndrome. Gastroenteritis had its peak incidence in the under 5 year group, whereas the pseudo-appendicular syndrome was more frequent in the 10--19 years age group. There was a distinct seasonal peak in late autumn. The significant association with Salmonella isolation from the stool of the same patient has been confirmed.


Yersiniosis in California.

Yersiniosis in California. Thirty-three strains of Yersinia enterocolitica representing 11 different serotypes were identified from human isolates in California between 1968 and mid-1977. The most frequently encountered serotype, 0:5,27, was identified in 8 cases. Twenty-one strains, representing five serotypes, were esculin- and salicin-negative, and were considered to be the primary cause of disease in the majority of these cases. The remaining strains, representing six serotypes, were esculin- and salicin-positive, and appeared to be 'opportunistic' organisms. They were isolated from 12 patients, 8 of whom had underlying conditions, and 4 or whom were asymptomatic. From 1968 to 1977, 13 strains of Y. pseudotuberculosis isolated from humans were submitted to our laboratory for identification or confirmation. Ten were serotype I and three, serotype III. Sources of isolation included blood (6); blood and liver abscess (1); blood and urine, and liver at autopsy (1); feces (2); biopsy of terminal ileum (1); abdomonal abscess (1); and neck abscess (1). The results of serotyping and biochemical characteristics of the strains, as well as the clinical histories of the patients, are discussed.


The first isolation of human Yersinia enterocolitica in Brazil: case report. The isolation of Yersinia enterocolitica from humans in Brazil has never been described before. The present report describes the isolation of an Y. enterocolitica isolate from a patient with clinical symptoms resembling appendicitis. The isolate showed typical sensitivity to the drugs and biochemical tests, with the exception of the motility at 22 degrees C, that was negative. The strain agglutinated with antisera 03 and the patient's serum showed an antibody titer of 1:80 against Y. enterocolitica serotype 03.


Waterborne Yersinia enterocolitica in the midwest United States. One hundred forty strains of waterborne Y. enterocolitica were isolated from Wisconsin and Colorado rivers, lakes and wells between October 1974 and March 1976- Direct-plating of unconcentrated water specimens on deoxycholate-citrate-mannitol (Y-M) agar resulted in 89 isolates. Prolonged incubation of specimens in cooked meat broth produced 51 additional strains. Most organisms were indole-positive, Niléln biotype 1 with 24% belonging to the rhamnophilum subgroup. Twenty-three serotypes were represented with 13% reacting as 0:4,32/33, 43% of the isolates could not be serotyped. Twelve organisms were phagetyped as either XO or XZ.


The first successful isolation and identification of Yersinia enterocolitica in Iran. Since 1967, more than 2,000 specimens have been examined for the possible existence of Yersinia enterocolitica in Iran. Most of the specimens were stool and appendices. For primary isolation SS and EMB media were used and the cultures were incubated at 37 degrees C. In 1976 we isolated the first strain of Y. enterocolitica from the stool of a 10-month-old girl. She was suffering from chronic diarrhea. This strain was the first strain of Y. enterocolitica to be successfully isolated in Iran. It belongs to serotype 03,--biotype 4-phage type VIII. It has all the classical characteristics of Y. enterocolitica. However, in contrast to the strains found in northern Europe, it ferments d-xylose. Our finding was confirmed by internationally accepted Yersinia centers.


Isolation of Yersinia enterocolitica from swine at an abattoir in Sweden. Yersinia enterocolitica is presented from a taxonomic point of view. A review about the increased frequencies of isolations of Y. enterocolitica from domestic and wild animals in Europe is given. Recent studies from different countries strongly suggest swine as a source of Y. enterocolitica infection to humans. The frequencies of isolation of the O-group I (serotype 3) of this bacteria from swine at a Swedish abattoir is presented. The occurrence of positive cases in lots of swine sent to slaughter from different herds range from 0.6 to 8.0%.


Carriage of Yersinia enterocolitica serotype 3 by pigs as a source of human infection. Bacteriological cultures were made from pigs' tongues bought in several Belgian butchers' shops, for 3 years in succession. From 302 samples 168 Yersinia enterocolitica strains were isolated, all of serotype 3, except three strains belonging to serotype 9. The isolation rate ranged from 53 to 62.5%, depending on the year. The modified Rappaport broth supplemented with carbenicillin proved to be highly superior to the cold enrichment method for recovering the organism from this material. It is assessed that Y. enterocolitica of serotype 3 is a normal inhabitant of the oral cavity of pigs in some countries. This source of organism might play a prominent part in the epidemiology of human infections caused by these bacteria.


Occurrence of Yersinia enterocolitica in the throat of swine. Yersinia enterocolitica serotype 0 3 was isolated from 84 (30%) of 282 throat swab cultures from bacon pigs at slaughter. Other serotypes of Y.e. were not isolated. All the isolations were made by the cold-enrichment method. The serum agglutinin titres against serotype 0 3 were low in most of the pigs examined. The rate of isolation of the organism increased with rising serum titre. In Denmark, Y.e. serotype 0 3 would appear to be a common inhabitant of the throat of swine.


Yersinia enterocolitica infection in children: 4 years experience in the Montreal urban community. From 1973 to 1976, a total of 146 strains of Yersinia enterocolitica was isolated from children at the Ste. Justine Hospital and Montreal Children's Hospital. All strains tested were of serotype 0:3, biotype 4. The majority (80%) of children from whom Y. enterocolitica was isolated were under 5 years of age and in 74 of 93 cases reviewed diarrhea was the predominant symptom. Case reports on 2 patients with unusual clinical features are also presented.


Speciation in Yersinia.

Speciation in Yersinia. Deoxyribonucleic acid (DNA) relatedness among members of the genus Yersinia and the biochemical reactions of these organisms were compared. These data were used to reassess speciation within the genus Yersinia, and three new species were proposed. These are Yersinia ruckeri sp. n., formerly called the redmouth bacterium; Yersinia intermedia, sp. n., formerly a rhamnose-positive, raffinose-positive, melibiose-positive biogroup within Yersinia enterocolitica; and Yersinia frederiksenii sp. n., formerly a rhamnose-positive, raffinose-negative, melibiose-negative biogroup within Y. enterocolitica.


An experimental study of the pathology and ecology of Yersinia enterocolitica infection in mice. Four experiments are described in which laboratory mice were infected with Y. enterocolitica using an American serotype 0:8 (WA) and two European strains, serotypes 0:3 and 0:9. The pathogenicity and histopathological responses of strain WA (0:8) were determined in the Porton white outbred mouse by three route of inoculation. The LD50 after infection by the intraperitoneal route was 8.8 x 10(1) organisms, which is similar to results obtained by previous workers using disease-free and hybrid mouse strains. European strains 0:3 and 0:9 were shown to infect the Porton white outbred mice when injected intraperitoneally but no deaths occurred. Chronic faecal excretion was demonstrated up to 135 days. Specific antibodies were detected in the 0:3 and 0:9 infected mice and the immune response was further assessed by challenging the excreter mice with 50LD50S of the virulent WA strain. A significant degree of protection occurred in mice previously injected with 10(7) organisms of the avirulent strains. No evidence of phenotypic variation, as measured by 40 markers, was detected in 67 isolates of Y. enterocolitica recovered during the course of the four experiments. These results suggest that laboratory rodents could be a useful model for studying the infection produced by virulent and avirulent strains, and since it has been clearly established that a wide range of serotypes and non-typeable strains may be isolated from wild rodents, our findings could be extrapolated to the wildlife situation. Further work on the laboratory model could give a more detailed insight into the mechanism and extent to which rodents act as reservoirs of Y. enterocolitica.


Host responses to infection with Yersinia enterocolitica. The mechanism of protective systemic immunity to Y. enterocolitica infection in mice was studied. It was determined that active immunization of mice with heat-killed yersiniae would induce a protective immune response against an intravenous challenge. This protective response was proven to be humoral in nature when it was demonstrated that passively transferred serum, but not cells, protected normal recipients against a lethal challenge. It was also shown that the immune serum caused opsonization of the microorganisms resulting in enhanced phagocytosis and killing of yersiniae by reticuloendothelial organs.


Differentiation of Yersinia enterocolitica strains in subgroups after biochemistry and serology. A system for the differentiation of Yersinia enterocolotica strains and Yersinia enterocolitica-like strains is introduced using the biochemical and O-serological characters of the strains and their sources. Seven subgroups are proposed. I--III are indole-negative strains. IV include strains which are indole-positive but lack the ability to split aesculin and to ferment salicin. These strains mostly belong to serotype 0:8 and are found in the USA or in Canada. In subgroups V--VII the strains are also indole-positive but they can also ferment salicin and split aesculin. Subgroup V strains cannot ferment rhamnose. Subgroups VI and VII include the strains which ferment rhamnose, and in subgroups VII, to which strains with serotype 0.17 belong, melibiose is also often fermented. Using cross-agglutination studies it has been possible to make a subdividing of the serotypes 0:4, 0:5, 0:6 and 0:7.


The isolation of urease-negative strains of Yersinia enterocolitica. Three urease-negative Y. enterocolitica strains of biotype 2 have been isolated from stool and urine of healthy persons. They were diagnosed on an isolation medium used routinely in the bacteriological laboratory of the Regional Station of Hygiene in Ceské Budĕjovice for isolation and diagnosis of gram-negative facultatively anaerobic-fermenting rods. An important characteristic was the smell of the culture, typical of all the indole-positive strains of Y. enterocolitica.


Biotypic and serotypic profiles of 367 Yersinia enterocolitica cultures of human and environmental origin in the United States. Between 1972 and March 1977, 367 cultures of Yersinia enterocolitica were examined for biotypic and serotypic characteristics by Plague Branch, Vector-Borne Diseases Division, Center for Disease Control. Standard biotyping tests were performed. Serotyping antisera used contained somatic serofactors 1 through 9, 11 through 21, 24, 32, and two new types designated 'Arizona' and 'Tacoma'. The cultures examined included 68 from human illnesses; 43 from 12 species of vertebrate and invertebrate animals; 43 from raw meats, milk, or seafood; and 215 from 154 different water samples. Geographic origins of the cultures included 16 states of the USA and four provinces of Canada.


Cultural characteristics of Yersinia enterocolitica and Yersinia pseudotuberculosis on differential media. A study was made of the cultural characteristics of 43 strains of Yersinia enterocolitica and 49 strains of Yersinia pseudotuberculosis on media commonly used for the isolation and differentiation of enteric bacteria. Best growth of the yersinia occurred on MacConkey agar, followed by growth on SS agar; none of the strains of either species developed colonies on brilliant green agar. The Y. pseudotuberculosis strains developed only one type of colony on MacConkey, SS, EMB, Hektoen, and XLD media whereas Y. enterocolitica exhibited more than one type of colony on all of the media except MacConkey and SS agar. The 'lactose-positive' colonies of Y. enterocolitica were especially distinctive on EMB. These were quite dark, with or without a metallic sheen, and closely resembled the colonies of lactose fermenting Escherichia coli on EMB agar. Strains of both Y. enterocolitica and Y. pseudotuberculosis grew better on the differential media at 35 degrees C than at 22 degrees C but the growth of Y. pseudotuberculosis was considerably slower than that of the other species.


Prevalence of unique Yersinia enterocolitica in the area of the Mount Sinai Hospital, New York, N.Y. The incidence of infection due to Yersinia enterocolitica is unknown in the United States as well as in a given geographic locale such as New York City. Comparison of 10 Y. enterocolitica strains recovered at nine hospitals in the New York City area to 22 isolated at The Mount Sinai Hospital revealed striking differences in clinical presentation of disease, biochemical behavior of the isolates and their serological profiles. The 10 strains were from patients with 'classical syndromes', were biochemically typical and of a serological profile (0:1 or 0:2, 0:5, 0:8) known to produce these syndromes in the United States. The 22 Mount Sinai isolates were isolated from patients with milder infections, were biochemically atypical, and contained serotypes (0:17, 0:16, 0:12) seldom associated with human infections.


Stereochemical and dynamic aspects of genetic recombination. The conformational features of three key intermediates in the gene conversion pathway are described. We have found that the dimensions of the trans turned structure involved in crossover are incompatible with normal H-bond formation occurring in opposing strands within the confines of 23 A axially separated double helices. However, if the separation is reduced to 18 A, slight rotation around the axis can give rise to crossover. A mechanism is proposed in which the crossover junction for short sequences migrates by torsional oscillations. This process is rapid enough to permit strand exchange of 100 bases in less than a millisecond. It is shown that the rotational diffusion mechanism becomes rate limiting for the crossover processes involving longer sequences.


Translocatable elements in Staphylococcus aureus. The properties of the first translocatable element in Gram-positive bacteria, a 5.2 kb segment encoding erythromycin resistance in S. aureus, are described. This element translocates from plasmid to multiple chromosomal sites and from chromosome to multiple plasmid sites, sometimes causing insertional inactivation and deletion. The genetic control of translocation and its role in natural plasmid evolution are discussed and preliminary evidence for translocation of penicillin and chloramphenicol resistance is presented. In the latter case, translocation involves in intact plasmid.


A new Q wave in the electrocardiogram in patients operated upon for ischaemic heart disease. In 305 patients operated upon for symptomatic ischaemic heart disease, a series of resting electrocardiograms, obtained during the first days after operation, was evaluated. A new Q wave was found in 10% of the patients. The genesis of this EGG change had not correlation with the patients' age and sex, presence of hypertension and diabetes mellitus, tobacco smoking, blood cholesterol level, functional calss of angina pectoris, previous myocardial infarction, the number of affected coronary arteries, duration of extracorporeal circulation or anoxic circulatory arrest, and peroperatively measured graft blood flow. A new Q wave after revascularization occurred more frequently in patients with multiple venous aortocoronary bypasses. The new Q wave is an EGG manifestation of myocardial necrosis with subsequent local disturbance of left ventricular function.


Incidence and fatality of acute myocardial infarction in the community. The incidence rate for acute myocardial infarction (AMI; diagnostic categories "definite AMI" + "possible AMI" + "insufficient data"), defined as number of cases per 10 000 population (20 years and older) and year, are highest in Berlin, GDR (63 for males, 42 for females), intermediate in Budapest (46/22) and lowest in Warsaw (38/21). In Budapest and Warsaw younger and middle-aged men suffer more frequently from AMI than in Berlin, while in the GDR capital AMI is more frequent in older men and women. In younger and middle-aged groups AMI occurs in women ten years later than in men. After standardization for age, the AMI incidence rates are not significantly different between Budapest and Warsaw, but are significantly higher in Berlin, particularly for older women. The standardized fatality rates of AMI (percentage of cases died within 28 days from all cases) for males were equally high for Berlin and Budapest (each about 50%), but in Warsaw significantly lower (42%). For females they are significantly highest in Berlin (69%), intermediate in Budapest (57%) and significantly lowest in Warsaw (40%). This is due mainly to an excess fatality within the oldest groups in the Berlin Register.


The first heart sound abnormalities accompanied with alteration of systolic time intervals in incipient heart failure. A phonocardiological analysis of the first heart sound was made and systolic time intervals were measured in 40 patients (ischaemic heart disease, hypertensive heart disease, cardiomyopathies) with incipient cardiac failure (functional groups I--II according to the NYHA) with auscultatory changes of the first heart sound and in controls of randomly selected healthy persons or patients in whom cardiopulmonary disease was excluded. The patients in all diagnostic groups differed significantly (P less than 0.05--0.001) in practically all the phonocardiographic indicators from the controls. The most constant abnormal finding was a pathological split of the first heart sound which may be divided into three phonocardiographic forms. Simultaneously, systolic time intervals alterations (P less than 0.02--0.001) were also found in these patients and indicated a lowered performance of the left ventricle. The results suggest that 1) a certain relation exists between systolic time intervals and the phonocardiographic pattern of the first heart sound in patients with cardiovascular diseases and those without it; 2) the modified (pathologically splitted and prolonged) first heart sound could be a sign of incipient cardiac failure.