Capsular-enhanced repair of the short external rotators after total hip arthroplasty

Higher dislocation rates have been reported with the posterior approach to the hip. Empirical studies suggest that careful repair of the posterior structures significantly reduces this risk. However, studies examining the integrity of repair using plain radiographs and metallic markers have reported high failure rates. To explain this discrepancy, we performed a study using radiostereometric analysis to assess the repair. Ten patients were recruited. Markers were placed into the capsule and bone. The capsule and conjoined short external rotators were repaired through drill holes in bone. At 3 months, stress radiostereometric analysis radiographs were taken in internal and external rotation. Eight of 10 patients had a mean of 3.51-mm difference in separation, suggesting that the repair was intact. We recommend careful repair of posterior structures when using the posterior approach to reduce the risk of dislocation.