Cementless Total Hip Arthroplasty With Paavilainen Femoral Shortening Osteotomy Can Provide Good Results at 10 years in Patients Who Have Crowe IV Developmental Dysplasia of the Hip.

BACKGROUND: The aim of this study was to present the clinical and radiologic results of primary total hip arthroplasty (THA) using the femoral shortening osteotomy technique described by Paavilainen in patients who have Crowe IV developmental dysplasia of the hip (DDH).

METHODS: We retrospectively analyzed the results of primary THA using the Paavilainen technique in 335 hips. The mean follow-up was 10.2 years. The degree of limp, leg-length discrepancy, and patient satisfaction were assessed. The Oxford Hip Score was used to examine functional outcomes. A number of radiographic parameters were also assessed.

RESULTS: The most common reason for revision surgery was non-union of the distally advanced greater trochanter. This complication was observed in 22 hips (6.5%). The ten-year survival for acetabular components, it was 97.3%, and for femoral components was 98.7% with aseptic loosening as the end point, and 85.9% with re-operation for any reason as the end point. Patients demonstrated improved functional outcomes. The mean limb lengthening was 27.8 mm. Non-union was more common if the contact length of the proximal femoral fragment with the lateral surface of the distal femoral fragment was less than 35 mm.

CONCLUSIONS: Cementless primary THA using the femoral shortening osteotomy technique described by Paavilainen in patients who have Crowe IV DDH demonstrates good clinical and radiologic postoperative results. If the contact between the fragments after osteotomy is less than 35 mm, there is a high risk of non-union, and supplemental fixation may be warranted.