ANTERIOR FEMORO-ACETABULAR IMPINGEMENT DUE TO ACETABULAR RETROVERSION

TLDR

Anterior femoro‑acetabular impingement caused by acetabular retroversion presents with clinical symptoms, a positive impingement test, and MRI rim lesions, and periacetabular osteotomy has been proposed as a reorientation strategy in young adults. The study aimed to determine whether symptomatic anterior femoro‑acetabular impingement due to acetabular retroversion can be effectively treated with periacetabular osteotomy. Twenty‑nine hips in twenty‑two patients underwent periacetabular osteotomy, with arthrotomy in twenty‑six hips to assess intra‑articular lesions, and pre‑ and postoperative radiographic and clinical evaluations—including range of motion, Merle d'Aubigné scoring, and anterior center‑edge angle—were performed over an average 30‑month follow‑up. Postoperatively, the anterior center‑edge angle decreased from 36° to 28°, internal rotation, flexion, and adduction increased by 10°, 7°, and 8°, respectively, the Merle d'Aubigné score rose from 14.0 to 16.9 with 26 hips achieving good or excellent results, and only three hips required additional surgery, confirming the effectiveness of periacetabular osteotomy.

Abstract

This study was performed to evaluate whether symptomatic anterior femoro-acetabular impingement due to acetabular retroversion can be treated effectively with a periacetabular osteotomy.The diagnosis of femoro-acetabular impingement was based on clinical symptoms, a positive anterior impingement test, and findings of acetabular rim lesions on magnetic resonance imaging. The radiographic diagnosis of acetabular retroversion was based on the cross-over and posterior wall signs. Twenty-nine hips in twenty-two patients (average age, twenty-three years) underwent a periacetabular osteotomy. An arthrotomy was performed in twenty-six hips in order to visualize intra-articular lesions and, in selected cases, to improve a low femoral head-neck offset. The range of motion of the hip was measured, clinical evaluation was performed with use of the score described by Merle d'Aubigné and Postel, and the anterior center-edge angle of Lequesne and de Sèze was measured on radiographs preoperatively and at the time of the latest follow-up.The duration of follow-up averaged thirty months (range, twenty-four to forty-nine months). The anterior center-edge angle of Lequesne and de Sèze decreased significantly from a preoperative average of 36 degrees (range, 26 degrees to 52 degrees ) to a postoperative average of 28 degrees (range, 16 degrees to 46 degrees ) (p = 0.002). There was a significant increase in the average range of internal rotation (10 degrees, p = 0.006), flexion (7 degrees, p = 0.014), and adduction (8 degrees, p = 0.017). The average Merle d'Aubigné score increased from 14.0 points (range, 12 to 16 points) preoperatively to 16.9 points (range, 15 to 18 points) postoperatively (p < 0.001), and the result was good or excellent for twenty-six hips. Three hips underwent subsequent surgery: one, because of early postoperative loss of reduction; one, for correction of posteroinferior impingement; and one, because of recurrent signs of anterior impingement.Periacetabular osteotomy is an effective way to reorient the acetabulum in young adults with symptomatic anterior femoro-acetabular impingement due to acetabular retroversion