Modified Enhanced Posterior Soft Tissue Repair Results in a Negligible Dislocation Rate After Hip Resurfacing

Abstract

Using a modified enhanced posterior soft tissue repair (EPSTR), there were no early dislocations observed (0%) after metal-on-metal hip resurfacing (MOMHR) or femoral head resurfacing hemiarthroplasty (FHRH) at a minimum of 3 months follow-up. Dislocation persists as one of the most common and potentially debilitating early complications of total hip arthroplasty (THA) performed with a posterior approach, occurring at a rate of 1%-2% in most studies. The introduction of an EPSTR by Pellicci et al in 1998 significantly reduced the occurrence of early postoperative dislocation following posterior approach THA. This study evaluates the early dislocation rate after MOMHR and FHRH when an adapted version of EPSTR is used. A single surgeon performed 123 MOMHR and 26 FHRH procedures using a modified EPSTR on 133 patients. The average age in the MOMHR group was 51.0 ± 9.5 (range 17-76) and body mass index was 28.1 ± 4.8 (range 17.9-47.2); the average age in the FHRH group was 43.8 ± 12.0 (range 20-64) and body mass index was 27.9 ± 3.7 (range 19.8-35.1). The most common diagnosis in the MOMHR group was osteoarthritis, while FHRH was performed exclusively for avascular necrosis. All patients received a modified EPSTR and were followed for a minimum of 3 months. No patients were lost to follow-up. Using EPSTR, there were no early dislocations observed (0%) in either the MOMHR or the FHRH group at a minimum of 3 months follow-up. This study shows that using a modified EPSTR for MOMHR and FHRH has the potential to decrease early dislocation rates to a negligible level. These results have prompted the following lessening of postoperative precautions: No flexion greater than 120°, no adduction greater than 20°, and no internal rotation past 10°.