Comparative Assessment of Subtrochanteric Shortening Osteotomy and Paavilainen’s Proximal Osteotomy in Total Hip Arthroplasty for Crowe III–IV Dysplasia

Abstract

The purpose of the study — to compare the results of the subtrochanteric shortening osteotomy and Paavilainen proximal osteotomy in the total hip arthroplasty for Crowe III and IV dysplasia. Material and Methods. It was performed 36 hip arthroplasties in the patients with Crowe III (12) and IV (24) dysplasia. Two methods of the shortening osteotomy were used: Paavilainen osteotomy (22) and subtrochanteric osteotomy (14). The average follow-up was 42.3±22.7 months (from 6 to 88). Among the patients, there were 25 (75.8%) women and 8 (24.2%) men with the average age of 51.5±13.1 and 34.6±20.4 years, respectively. Results. The lateral acetabular deficiency required the structural repair of the femoral head in 16.7% of the cases. The average length of the osteotomized fragment was 56.8±16.3 mm, the caudal displacement of the greater trochanter apex — 47.0±15.6 mm, the limb lengthening — 30.1±10.9 mm without the statistically significant difference between the groups. The consolidation was achieved on average in 7 months. The Harris score improved on average from 37.6±10.1 points to 76.1±17.6, p0.001 (78.1±15.3 in Paavilainen group and 72.9±20.9 in the subtrochanteric). The overall HOOS score increased from an average of 34.6±12.4 to 74.6±18.6 points, p0.001 (78.1±15.9 in Paavilainen group and 69.1±21.7 in the subtrochanteric). The statistically significant differences between the groups after the surgery were found only in the HOOS pain section. Paavilainen group showed higher scores. Various postoperative complications occurred in 27.8% of cases, 2.4 times more often in the subtrochanteric group. The revision was required in 4 cases out of 36 (11.1%): 2 cases (9.1%) in Paavilainen group and 2 cases (14.3%) in the subtrochanteric. The survival rate of the femoral component throughout the sample was 97.2%. There was only one case of the femoral component replacement in the subtrochanteric group. Conclusion. Both the subtrochanteric shortening osteotomy and Paavilainen proximal osteotomy have good reconstructive capabilities and sufficient efficacy. We were not able to identify the clear advantages of any of the described options for shortening osteotomy, probably due to the insufficient number of observations. In our practice, we give a preference to subtrochanteric shortening osteotomy of the femur.