Intra-articular hyaluronic acid vs platelet-rich plasma in the treatment of hip osteoarthritis

Aim: To compare the efficacy of ultrasound-guided intra-articular (IA) treatment with platelet-rich plasma (PRP) versus viscosupplementation (hyaluronic acid [HA]) in hip osteoarthritis. Material and methods: A total of 43 patients affected by monolateral severe hip osteoarthritis (OA) were included in the study. Patients were randomized to receive either intra-articular PRP (3 ml) or HA (30 mg/2 ml; 1,000-2,900 kDa), 3 injections in total - 1/week. Clinical assessments for each patient were made at baseline (T0), 4 (T1), and 16 weeks (T2) of follow-up. The primary efficacy outcome was pain reduction as measured by VAS and by WOMAC pain subscale. Results: Data analysis revealed that, compared to T0, in the PRP-treated group VAS scores significantly decreased at T1 but not at T2, thereby indicating an early effect on pain which was not maintained at a longer term follow-up. In the HA group a significant decrease of both VAS and WOMAC values was registered only between T0 and T2. Conclusions: Intra-articular PRP had an immediate effect on pain that was not maintained at longer term follow-up when, on the contrary, the effects of intra-articular HA were evident.