Primary total hip arthroplasty using modified posterior approach through quadratus femoris flap osteotomy; comparison with conventional posterior approach.

ABSTRACT

INTRODUCTION: The quadratus femoris muscle has not attracted attention as a structure for surgical exposure during posterior hip approaches. We sought to introduce a modified posterior approach through the quadratus femoris muscle area only, by flap osteotomy, which we have named the quadratus femoris osteotomy (QFO) approach. We compare this with the conventional posterior approach to determine the effectiveness of the new technique. METHODS: We retrospectively reviewed the medical records of 329 patients (383 hips) who had undergone primary total hip arthroplasty (THA) between March 2006 and January 2013 by a single hip surgeon. The conventional group consisted of consecutive 118 patients (138 hips) who had undergone THA using the conventional posterior approach. The QFO group consisted of consecutive 101 patients (120 hips) who were treated with THA using the QFO approach. RESULTS: The 2-year postoperative average Harris hip score were 88.8 ± 6.6 in the conventional group and 93.1 ± 6.9 in the QFO group. The 2-year postoperative average WOMAC scores were 20.8 ± 6.7 in the conventional group and 14.1 ± 6.6 in the QFO group. Complications in the conventional group were 2 deep vein thrombosis (DVT)s, 1 intraoperative fracture, and 6 posterior dislocations; the QFO group experienced 1 DVT and 3 intraoperative fracture. No dislocation was noted within 2 years after surgery. CONCLUSIONS: Although further studies are needed to confirm the validity of our findings, a modified posterior approach using a quadratus femoris flap osteotomy could be an option worth considering among the variants of posterior approaches in THA.