Femoroacetabular impingement: is hyaluronic acid effective?

PURPOSE: Femoroacetabular impingement may predispose to the development of hip osteoarthritis. Conservative treatments are effective in the short term, but surgery is often required. Aim of this paper was to report the short-term results on hip pain and function after ultrasound-guided injections of hyaluronic acid. METHODS: In this open prospective trial, twenty patients suffering from mild femoroacetabular impingement were enrolled. Each patient received a 2-ml intra-articular ultrasound-guided injection of hyaluronic acid at baseline and after 40 days; the same dosing schedule was repeated after 6 months. The clinical evaluation was performed at baseline and after 6 and 12 months of follow-up. Pain score, Lequesne Index, Harris Hip Score and anti-inflammatory medication consumption were measured. Adverse events were also registered. RESULTS: Twenty-three hips (3 bilateral cases) were treated. Pain decreased from 6.7 ± 1.3 to 3.7 ± 1.8 and to 1.7 ± 1.8 after 6 and 12 months, respectively; Lequesne Index was reduced and the mean Harris Hip Score improved from 83.3 ± 6 before treatment to 88.2 ± 4.7 at 12 months. Consumption of anti-inflammatory drugs was also reduced, from 14 to 4 subjects and from 3.6 ± 2.2 to 1.3 ± 1.3 tablets/week. Local side effects after injection were observed only in 2 cases. CONCLUSIONS: Hyaluronic acid is safe and effective in the treatment of mild femoroacetabular impingement, with significant pain reduction and function improvement.