Spherical periacetabular osteotomy via para-sartorial intermuscular approach with bikini incision for patients with acetabular dysplasia: surgical technique and preliminary results

Purpose: This study introduces a new technique, spherical periacetabular osteotomy (SPO), performed via a para-sartorial intermuscular (PSIM) approach with a bikini incision, aiming to optimise the benefits of SPO, including preservation of muscles and providing cosmetic advantages.

Methods: Overall, 57 joints of 52 patients (mean age 36 ± 17 years) underwent SPO via the PSIM approach. Preoperative osteoarthritis was classified according to Tönnis grade, with 34 and 23 hips categorised as grades 0 and 1, respectively.

Results: The modified Harris Hip Scores significantly improved from 75 ± 10 to 96 ± 8 points at 6 months postoperatively. The lateral centre-edge angle improved from 6 ± 8° preoperatively to 30 ± 8° postoperatively, with a mean correctional angle of 24 ± 9°. Paresthetica of the lateral femoral cutaneous nerve occurred in 7 joints (12.3%) 3 months postoperatively. All cases except 1 achieved bone union within 3 months, and a nonunion case required additional surgery.

Conclusions: Although the long-term results are not yet available, SPO via the PSIM approach demonstrates promising outcomes without significant complications. Furthermore, using the PSIM approach with a bikini incision has the advantages of muscle preservation and excellent cosmesis, which are delighted for young patients.