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[MINIMALLY INVASIVE FIXATION UNDER COMPUTER-ASSISTED NAVIGATION FOR TREATMENT OF PERIACETABULAR FRACTURES, ANTERIOR AND POSTERIOR PELVIC RING FRACTURES].

OBJECTIVE
To investigate the application and technical essentials of computer-assisted navigation in the surgical management of periacetabular fractures and pelvic fractures.


METHODS
Between May 2010 and May 2011, 39 patients with periacetabular or anterior and posterior pelvic ring fractures were treated by minimally invasive fixation under computer-assisted navigation and were followed up more than 2 years, and the clinical data were analyzed retrospectively. There were 21 males and 18 females, aged 15-64 years (mean, 36 years). Fractures were caused by traffic accident in 23 cases, crush injury in 6 cases, and falling from height in 10 cases. Of them, 6 cases had acetabular fractures; 6 cases had femoral neck fractures; 18 cases had dislocation of sacroiliac joint; and 15 cases had anterior pelvic ring injuries. All patients were treated with closed or limited open reduction and screw fixations assisted with navigation.


RESULTS
Eighty-nine screws were inserted during operation, including 8 in the acetabulum, 18 in the neck of the femur, 33 in the sacroiliac joint, and 30 in the symphysis pubis and pubic rami. The mean time of screw implanted was 20 minutes (range, 11-38 minutes), and the average blood loss volume was 20 mL (range, 10-50 mL). The postoperative pelvic X-ray and three dimensional CT scan showed good reduction of fractures and good position of the screws. No incision infection, neurovascular injury, or implant failure occurred. All patients were followed up 27-33 months with an average of 29.6 months. The patients could walk with full weight loading at 6-12 weeks after operation (mean, 8 weeks); at last follow-up, the patients could walk on the flat ground, stand with one leg, and squat down, and they recovered well enough to do their job and to live a normal life.


CONCLUSION
Minimally invasive fixation under computer-assisted navigation may be an excellent method to treat some specific types of periacetabular and anterior and posterior pelvic ring fractures because it has the advantages of less trauma and blood loss, lower complication incidence, and faster recovery.