Hyaluronic Acid Therapy in Hip OA Does Not Perform Equally in Osteoarthritis Secondary to Juvenile Idiopathic Arthritis When Compared to Primary Osteoarthritis: A 2-Year Preliminary Evaluation.

Objective: Hip involvement in juvenile idiopathic arthritis (JIA) is one of most important causes of pain and disability. Total hip arthroplasty (THA) is considered the standard when medical approaches fail to relieve pain. However, THA is problematic for many reasons. As current literature lacks studies valuating medical management of osteoarthritis (OA) secondary to JIA, we assessed the long-term pain relief effect of US-guided intra-articular viscosupplementation in hip osteoarthritis secondary to JIA versus primary OA under different etiological conditions.

Methods: Patients in both groups received intra-articular Hylan G-F 20 2 ml once a month for 3 consecutive months and every 6 months for 2 years as maintenance. Effectiveness (VAS and WOMAC), NSAID/analgesic consumption, tolerability, withdrawals and reason for discontinuation were collected at each time point. An inverse probability weighting was used to balance the two groups.

Results: We retrospectively retrieved data of 14 JIA patients and 26 primary OA. Weighting successfully accounted for differences between the disease groups supporting the results. Viscosupplementation led to an early and significant improvement of pain and function and concomitant decrease in NSAIDs consumption, while the response diverged over 1 year with loss of benefits in JIA. The worst outcome was observed in active JIA.

Conclusions: Duration of symptom relief after intra-articular injection of hyaluronic acid depends on the nature of arthritis. Multiple courses of viscosupplementation are required to maintain low-dose NSAIDs consumption in patients responsive to treatment while shortening the time between consecutive injections might provide persistent positive results in patients suffering from JIA.