Outcomes of Total Hip Arthroplasty for Congenital Hip Dislocation: A Retrospective Study.

Introduction Congenital hip dislocation (CHD) represents a long-standing public health issue in Morocco, with a late diagnosis often leading to advanced joint degeneration. While periacetabular osteotomy is preferred in young adults with preserved joint space, total hip arthroplasty (THA) becomes necessary in end-stage cases. However, THA poses challenges due to anatomical deformities and the increased likelihood of revision surgeries. This study evaluates the clinical, radiological, and functional outcomes of THA performed for CHD and compares them with existing literature. Materials and methods A retrospective study was conducted on 16 patients (19 hips) who underwent THA for CHD between 2008 and 2022 at a single orthopedic unit. Patients aged over 15 years with a minimum follow-up of 18 months were included. Clinical assessment using the Postel and Merle d'Aubigné score (PMA), radiological classification using modified Cochin classification (Co), and postoperative complications were analyzed. Results The mean age was 35.1 years, with a female predominance (68.75%). High dislocations (fixed or non-fixed) represented the majority of cases (75%). Preoperatively, the average PMA score was 8.41/18. Lameness was present in 87.5% of cases, and leg length discrepancies (LLDs) were significant, with an average of 39.25 mm, especially in high dislocations. All THAs used cemented components, with the use of bone grafts in three cases (18.75%) and release techniques in six cases (37.5%). The average follow-up period for patients was 22 months. At the final assessment, the mean PMA score postoperatively improved to 17.23/18. Complications included intraoperative fractures in three cases (18.75%), nerve injury in two cases (12.5%), dislocation in one case (6.25%), and trochanteric non-union in one case (6.25%). Conclusion THA in CHD can achieve satisfactory mid-term functional outcomes when performed with meticulous preoperative evaluation and adapted surgical techniques. However, the procedure requires significant surgical expertise due to its complexity and potential complications.