Treatment of hip instability after total hip replacement with pelvic osteotomy using a modified Stoppa approach.

INTRODUCTION AND IMPORTANCE: Hip dislocation remains a significant complication following total hip arthroplasty, even though its incidence has decreased. While closed reduction is typically performed for early dislocations, delayed or chronic dislocations often necessitate acetabular or femoral component revision.

CASE PRESENTATION: This document describes the treatment of hip dislocation in a 56-year-old patient through pelvic osteotomy without component revision. An acetabular component malposition was identified, exhibiting an 80-degree inclination and 20-degree cup anteversion. Owing to limited bone stock, a modified Stoppa approach was used for pelvic osteotomy to reduce acetabular inclination. The patient displayed remarkable clinical improvement, achieving a Harris Hip Score of 85 at the two-year check-up with no signs of dislocation.

CLINICAL DISCUSSION: Recurrent hip dislocation is difficult to manage. It frequently necessitates component revision, presenting a challenge due to issues with cup extraction and limited bone stock. Preoperative detection of loosened components is crucial. If it goes undetected, the extraction process can result in bone loss, potentially leading to pelvic insufficiency.

CONCLUSION: Successful revisions of hip arthroplasties can be achieved with geometric modifications to the pelvis.