[Arthroscopic resection of the cam deformity of femoroacetabular impingement]

Abstract

Objective: Resection of the cam deformity of the femoral head-neck junction in order to avoid femoroacetabular impingement and the development of secondary damage to the anterolateral acetabular rim.

Indications: Femoroacetabular cam impingement. Initial femoroacetabular pincer impingement. Advanced femoroacetabular pincer impingement with degenerative tear of the labrum.

Contraindications: Femoroacetabular pincer impingement with significant retroversion and intact acetabular labrum, coxa profunda or circumferential ossification of the labrum. Advanced osteoarthritis.

Surgical technique: Arthroscopy of the peripheral compartment via three portals with and without traction. The proximal anterolateral portal is used for the arthroscope, instrumentation is done via the anterior and classic anterolateral portal. After resection of the zona orbicularis and the inner parts of the iliofemoral ligament, the anterolateral cam deformity is resected without traction via the anterior portal. After distraction of the head from the acetabulum, the lateral and posterolateral cam deformity is trimmed via the classic anterolateral portal.

Postoperative management: Pain-controlled progression to full weight bearing over 1-4 weeks, continuous passive motion therapy and stationary bike for 6 weeks in order to avoid intraarticular adhesions.

Results: From 2004 through early 2007, 72 hip arthroscopies were performed for femoroacetabular impingement. So far, 48 patients (25 men, 23 women, mean age 37 years [17-65 years]) were followed up. After a mean follow-up of 18 months, the WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index) was significantly improved from 65 +/- 21 to 82 +/- 18 and the NAHS (Non Arthritic Hip Score) from 57 +/- 19 to 78 +/- 19.

Complications: two persistent branch lesions of the lateral femoral cutaneous nerve. One patient was surgically dislocated after 8 months for the treatment of a significant retroversion of the acetabulum; one patient underwent total hip arthroplasty after 1 year.