External fixation assisted reduction in the treatment for obsolete hip dislocations with limb discrepancy

Abstract Background: The purpose of this study is to evaluate a new method for treating obsolete acetabular dislocation with limb discrepancy by external fixation assisted pre-reduction. Methods: Thirteen patients admitted from January 2010 to February 2018 with a mean duration from injury to surgery of 5.0±2.1 months and an average preoperative leg-length discrepancy of 7.7±2.3 cm were enrolled in this study. The dislocation and associated acetabular fracture type, clinical outcomes and residual limb equality were evaluated. Results: All patients were posterior dislocations and nine presented with acetabular fractures and were followed-up at least 12 months. The average traction duration of external fixators was 28.8±8.0 days and all patients received second-stage open reduction and internal fixation. Six patients showed residual limb discrepancy within 2 cm. Patients showed significant improvement in hip function and pain relief. Complications including avascular femoral head necrosis and osteoarthritis occurred in 3 patients. Conclusion: Effective correction of limb discrepancy and improved function showed in patients with obsolete acetabular dislocations and limb equality using traction by external fixation combined with second-stage open reduction. The long-term outcomes need continued follow-up.