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Safety and efficacy of a self‐induced myofascial release protocol using a foam roller in patients with haemophilic knee arthropathy

Abstract Background Haemophilic knee arthropathy presents functional and structural alterations and chronic pain. Self‐induced myofascial release aims to treat fascial restrictions and improve functionality. Aim This study investigated the safety and effectiveness of a self‐induced myofascial release protocol in patients with haemophilic knee arthropathy. Methods Twenty‐five patients with bilateral haemophilic knee arthropathy were recruited (n = 50 knees). The patients followed an intervention protocol, with daily exercises for 8 weeks. The dependent variables were: safety of the technique (periodic telephone monitoring), joint state (Haemophilia Joint Health Score), pain intensity (visual analogue scale), pressure pain threshold (pressure dynamometer), range of motion (universal goniometer) and hamstring flexibility (Fingertip‐To‐Floor test). The resulting values were measured at baseline (T0) and after the intervention (T1). Paired t‐test compared the means between the assessments. Effect size was obtained using Cohen's d mean difference formula. The minimum detectable change of each variable was calculated. Results There were no cases of joint bleeding either during or after the procedure. The results showed improvements after the experimental period in joint state (Mean difference [MD]: 1.38; 95% confidence interval [95%CI]: .94;1.81), pain intensity (MD: 1.19; 95%CI: .70;1.67), pressure pain threshold (MD: ‐23.25; 95%CI: ‐26.25;‐19.84), flexion (MD: ‐4.36; 95%CI: ‐5.70;‐3.01), loss of extension (MD: 4.10; 95%CI: 3.01;5.18) and hamstring flexibility (MD: 3.54; 95%CI: 2.61;4.46). Conclusions Myofascial self‐release using a foam roller is safe in patients with haemophilic knee arthropathy. A myofascial self‐release protocol can improve perceived pain, range of motion and knee joint status, as well as hamstring flexibility in patients with haemophilic knee arthropathy.


K E Y W O R D S
haemophilic knee arthropathy, joint pain, range of motion, self-induced myofascial release

BACKGROUND
Haemophilia is a congenital coagulopathy characterized by a deficiency of a clotting factor. Haemophilia A is characterized by a deficiency of clotting factor VIII, while factor IX is missing in haemophilia B. Depending on the percentage of blood clotting factor there are three phenotypes: severe (< 1%), moderate (1-5%) and mild (> 5-40%). 1 Although it is a haematological disease, haemophilia is characterized by bleeding in the locomotor system. The joints are affected in 80% of cases (hemarthrosis), with bleeding in knees, elbows and ankles. 2 The recurrence of hemarthrosis induces biochemical and enzymatic alterations, and hypertrophy of the synovial membrane. Such recurrence leads to degenerative joint injury (haemophilic arthropathy). 3 Arthropathy represents degenerative, progressive and irreversible intraarticular damage. Haemophilic arthropathy is characterized by the loss of joint mobility, chronic pain, muscle atrophy and impaired proprioception. This leads patients to reduce their activities and social participation, thereby decreasing their perceived quality of life. 4 Injuries due to trauma and microtrauma by repeated and sustained overload predispose the conjunctive system to changes. These patterns favour pathological changes in the tissue that can cause mechanical and functional alterations as a consequence of modifications in the concentration and orientation of the collagen fibres of the conjunctival matrix. 5 In this way, healthy tissue in the vicinity of the site of injury or trauma can also be compromised and its function altered. 6 The fascial system, which is a heterogeneous network of connective tissue, 7 is built on a tensegrity-based architecture that provides stability to cells and the organism as well as mobility. 8 The mechanical changes undergone by the tensegrity system in order to adapt to the loads and to environmental factors, condition part of the physiological responses generated in the cells and the extracellular matrix.
Physiotherapy techniques using moderate mechanical loads have shown positive effects in terms of reducing fibrosis and swelling in patients with fascial tissue injury. 6 Through the fascia mechanoreceptors 9 fascial therapy attempts to change the orientation of the collagen fibres and alter the tone of the associated motor units. 10 A number of studies have reported the safety and efficacy of physiotherapy programs based on manual therapy using myofascial techniques in patients with haemophilic arthropathy of the ankle 11,12 and elbow. 13,14 Such studies noted a decrease in the frequency of hemarthrosis during the follow-up period, achieving improvements in range of motion and disability in patients with haemophilic arthropathy. Goto et al. 15 described that monitoring the perception of pain combined with use of a prophylactic treatment are key aspects in order to reduce the frequency of bleeding and pain, thus improving joint function. Acute and chronic processes lead to a shortening of the periarticu-lar structures, mainly the soft tissues and flexor muscles. The improved joint condition reported after the intervention period may justify the effectiveness of this intervention.
Self-induced myofascial release is a physiotherapy technique able to treat soft tissue restrictions with the help of a foam roller. Self-induced myofascial release involves patients using their own body weight, plus materials such as a foam roller, to exert pressure on the soft tissues affected. 16 Various studies have analysed the effectiveness of this technique in healthy athletes, achieving to reduce stress and muscle stiffness, as well as pain and swelling, while increasing range of motion in the hip, knee and ankle, when applied to the quadriceps, hamstrings, and plantar flexor muscles. 17 The direct pressure exerted with the patient's weight when using the foam roller on the treated region produces local mechanical and global neurophysiological effects that relax the tissues and attenuate the perceived pain in the treated region and surrounding tissues. 18 Self-induced myofascial release can improve the range of knee motion 19 and the pressure pain threshold at trigger points after a single session in healthy subjects. 20 Similarly, it has been noted that the decreased intensity of knee pain in athletes with chronic pain, after an 8-week self-induced myofascial release program, was maintained at 2 months follow-up. 21 The study hypothesis was that a self-induced myofascial release protocol is able to improve the perception of pain, range of knee motion, hamstring flexibility, and joint status in patients with haemophilic knee arthropathy. The aim of this study was to assess the safety and efficacy of a self-induced myofascial release protocol using a foam roller in patients with haemophilic knee arthropathy.

Study design
Prospective cohort study to assess the safety and effectiveness of a physiotherapy protocol using self-induced myofascial release with a foam roller in patients with haemophilic knee arthropathy.

Patient recruitment and selection
The patients were recruited from the Spanish Federation of Patients with on-demand or prophylaxis treatment and those with antibodies against clotting factor concentrates (inhibitors) were included.

Ethical considerations
Prior to the start of the study, the principal researcher explained the objectives, and possible risks and benefits of the intervention to the patients. After the oral presentation, they were given an information sheet with the data and characteristics of the study.

Measurement instruments
The patients were evaluated prior to the intervention and at 8 weeks, after the experimental phase, reproducing the initial evaluation under the same conditions. All evaluations were performed by the same physiotherapist, blinded to the study conditions.
The primary variable for measuring the safety of the intervention was the development of knee hemarthrosis. During the experimental phase, weekly telephone monitoring was carried out to evaluate any possible development of knee hemarthrosis or other complications (hematomas).
The six secondary variables were: joint health, pain intensity, pressure pain threshold, range of motion in knee flexion and extension, and hamstring muscle flexibility.
Joint state was measured on the Haemophilia Joint Health Score (HJHS). 22 This measuring instrument, specific for patients with haemophilia, assesses the joint condition in knees, ankles and elbows.
This scale includes eight items (joint swelling, duration of swelling, muscle atrophy, strength, crepitus on motion, flexion and extension loss, and pain) and scores range from 0 to 20 points per joint (the higher the score, the greater the degree of joint deterioration).
The intensity of joint pain was assessed using the visual analogue scale (VAS). 23 This scale rates knee joint pain with scores from zero to 10 points (from no pain to the maximum perceived pain).
The pressure pain threshold was measured using an algometer (Wagner FPIXTM Digital Algometer). Fischer's measurement proto-col was followed. 24 The instrument was attached to a hard rubber tip 1.1 cm in diameter, with a dial calibrated in kg/cm 2 and .1 kg/cm 2 divisions. The method described by Hogeweg et al. was used. 25 Before taking the measurements, patients were instructed to say "yes" as soon as pressure exerted by the algometer becomes slightly painful. With the instrument placed perpendicular to the skin surface, the pressure was increased at an even rate. 26 The unit of measurement is kg/cm 2 (the higher the score, the higher the pressure pain threshold).
The range of knee motion was measured with a universal goniometer, with one-degree increments. The protocol described by the American Academy of Orthopaedic Surgeons 27  Similarly, the pre-treatment evaluation included the main clinical, anthropometric and sociodemographic variables.

Intervention
This study followed the protocol designed by Meroño-Gallut et al. 29 for patients with haemophilic arthropathy. For its implementation, a  Table 1 shows the main methodological characteristics of the intervention. Figures 1 and 2 show the release of the hamstring muscle group and abductor muscles.

Sample size
The sample size was calculated using the statistical package G *

Statistical analysis
The statistical analysis was carried out with version 19.0 of the sta-  An intent-to-treat analysis was performed to analyse the results.

RESULTS
Through the periodic telephone follow-up over the 8 weeks of intervention, it was noted that none of the patients with haemophilia experienced intra-articular haemorrhagic events in the knee joint, derived from the intervention, or secondary to trauma.
After the intervention we observed changes (P < .001) in joint state

DISCUSSION
The aim of this study was to evaluate the safety and effectiveness of a self-induced myofascial release protocol in the treatment of patients with haemophilic knee arthropathy. Similarly, the results obtained after the study period suggest that a self-induced myofascial release protocol can be effective in improving joint state, pain, knee mobility, and hamstring flexibility in patients with haemophilic knee arthropathy. Safety of this therapy has already been reported in previous articles where myofascial release techniques were applied to patients with haemophilic ankle 11,12 and elbow 13,14,32 arthropathy. This joint release process can decrease the mechanical joint factor which can favour a reduction in the frequency of hemarthrosis. 33 After the intervention, we noted a significant decrease in the intensity of pain and a significant increase in the pressure pain threshold. Chronic pain is one of the most disabling clinical manifestations in patients with haemophilia, affecting their functional capacity and their perception of quality of life. The overall neurophysiological effect that roller pressure can cause by relaxing muscle tissue, reducing local and surrounding pain, has been described. This process is carried out through the afferent inputs of the central nervous system from the Golgi tendon reflexes, reducing the activity rate of the motor unit causing subsequent muscle relaxation. Likewise, the action of mechanoreceptors and nociceptors, by stimulation of the nervous system or by inhibition of the H reflex, could generate muscle relaxation. 34 The TA B L E 3 Means (and standard deviations), effect size and minimal detectable change of joint status, joint pain, range of motion and hamstring flexibility evaluated in the different assessments The study intervention employed a grid foam roller noting improvement in the pressure pain threshold of the knee. Scott et al. 34  From a clinical standpoint, these changes can be seen as increased tolerance to the stretching of muscles and surrounding tissues, as measured by changes in range of joint motion. 33 Our study reports changes in knee flexion and extension movements. The use of foam rollers has also shown to improve knee mobility in healthy subjects.
MacDonad et al. 16 reported an improvement in the range of motion of the knee from 9 • to 11 • in 11 healthy subjects after applying four 2min sessions with a Foam Roller in the quadriceps, at 24-48-h intervals.
Cheatham and Stull 33 described an enhanced knee range of motion after a 2-min daily protocol for 1 month, using a Foam Roller on the quadriceps.
Depending on the density, the surface and the diameter of the foam roller, the pressure exerted on the tissue varies and, thus the therapeutic effect. 36 The use of grid surface rollers, as in our study, has shown effectiveness in improving knee mobility. 34 This improvement may be due to the fact that the textured surface provides greater local myofascial deformation that increases the mechanical effects of the technique.
The protocol administered in this study by self-induced myofascial release involves direct pressure of the roller on the muscles. This can produce local mechanical and global neurophysiological effects that relax the tissues and relieve pain in the treatment site and surrounding tissue. 37 Similarly, it can reduce arterial stiffness, increasing arterial tissue perfusion and improving vascular endothelium functions related to tissue relaxation. 38 These changes can improve muscle flexibility, as reported for hamstring flexibility in our study. These results are consistent with the increase in hamstring flexibility in healthy subjects. 39 Self-induced myofascial release appears to be effective for the improvement of joint state in patients with knee arthropathy. Joints in which haemophilic arthropathy is present are exposed to an early degenerative process. Repeated joint bleeding, synovitis and chronic pain are elements that activate the inflammatory response and tissue repair mechanisms. Pain and chronic inflammatory processes generate changes in the connective structure. 40

Limitations of the study
The main limitation of this study is its design. Given the low prevalence of the disease, cohort studies in patients with haemophilia can be used mainly to evaluate the safety of the intervention. However, a clinical trial is needed to confirm our findings regarding the efficacy of myofascial self-release using a foam roller. The absence of measurements of lower limb functionality variables prevents us from assessing the relationship of this variable with the biomechanical function of the knee joint. This study does not show long-term results, so it is unclear how long the benefits achieved will last. Because this is a prospective cohort study without a control group, we are unable to comment on the effectiveness of myofascial self-release using a foam roller in the management of patients with haemophilic arthropathy.

Recommendations for future research
Randomized clinical studies are needed to confirm the results reported by this study. Likewise, methodological quality measures should be implemented, such as follow-up period, sample randomization and intent-to-treat analysis. The evaluation of variables such as muscle activation and muscle strength could provide information on the action of foam roller-based myofascial self-release in the muscles of the treated regions.

CONCLUSIONS
Myofascial self-release using a foam roller is safe in patients with haemophilic knee arthropathy. The intensity of pain and the pressure pain threshold may improve after following the myofascial self-release protocol using a foam roller in patients with haemophilic arthropathy.
A myofascial self-release protocol can improve range of motion, knee joint status, and hamstring flexibility in patients with haemophilia and knee arthropathy. Further randomized clinical studies should confirm the findings on safety and efficacy reported by this study.