Mesenchymal stem cell therapy for hip osteoarthritis : a systematic review

Hip osteoarthritis affects 8.7% of men and 9.3% of women over the age of 45 in the United States. Treatment of hip osteoarthritis includes physiotherapy, non-steroidal anti-inflammatory drugs and intra-articular injections (corticosteroid, platelet-rich plasma and hyaluronic acid). Total hip replacement is certainly an effective treatment but burdened with a non-negligible complication rate. Stem cell therapy represents a potential alternative for the treatment of patients with osteoarthritis. The authors performed a systematic review with the aim to analyze all clinical studies investigating the safety and efficacy of intra-articular mesenchymal stem cell injections for hip osteoarthritis. Nine studies satisfied inclusion criteria and were included in the review. The most important element that emerges from this analysis is that at the moment there is a lot of heterogeneity in the type of mesenchymal stem cells used (adipose versus medullary), in the site of collection and in the number of injections performed. The clinical results are overall satisfactory in the short follow-up (3-30 months, average 13.6 months). All the studies examined showed considerable clinical effectiveness in controlling pain and improving the functionality of patients with hip osteoarthritis in the short follow-up. Three of these studies demonstrated superiority in terms of duration of pain relief respect to standard therapies (injections of platelet-rich plasma and hyaluronic acid). From all this emerges the need to perform randomized controlled trials to evaluate the efficacy of mesenchymal stem cells compared to validated infiltrative treatments with platelet-rich plasma and hyaluronic acid.