Viscosupplementation for hip osteoarthritis: a systematic review and meta-analysis of the efficacy for pain, disability and adverse events.

OBJECTIVE: To assess the efficacy of viscosupplementation (HA) in hip osteoarthritis (OA) pain, disability and adverse events. DATA SOURCES: Pubmed, EMBASE, Cochrane Library, ClinicalTrials.gov database and specific journals up to March 2017. STUDY SELECTION: Randomized controlled trials comparing HA with any other intra-articular injection. DATA EXTRACTION: Performed according to Cochrane/GRADE criteria. Two authors extracted data, assessed risk of bias and quality of evidence. Random-effects meta-analysis was conducted. Protocol registered on PROSPERO under CRD42015017312 DATA SYNTHESIS: Eight RCTs were retrieved (n=807): four comparing HA to placebo (PBO); three with platelet-rich plasma (PRP), three with methylprednisolone (MPA), and one mepivacaine (MPV). Some RCTs had three arms. There is VERY LOW evidence that HA is not superior to PBO in pain at 3 months (SMD=-0.06 [95% CI -0.38; 0.25], p=0.69), and HIGH evidence that is not superior in adverse events (RR=1.21 [95%CI 0.79; 1.86], p=0.38). There is LOW evidence that HA is not superior to PRP for pain at 1 month. There is VERY LOW evidence that HA is not superior to PRP for pain at 6 and 12 months (mean difference in VAS in cm= -0.05 [95%CI -0.81, 0.71]; 1.0 [95%CI -1.5, 3.50]; 0.81 [95%CI -1.11, 2.73], respectively). There is HIGH evidence that HA is no different from MPA for pain at 1 month (SMD=0.02 [95% CI -0.18; 0.22], p=0.85). There is LOW evidence HA is no different from MPA for OMERACT-OARSI responders index at 1 month (RR=0.44 [95%CI 0.10; 1.95], p=0.28; There is HIGH evidence HA is no different from MPA for adverse events (RR=1.21 [95%CI 0.79; 1.87], p=0.38). CONCLUSIONS: We do not recommend viscosupplementation for hip OA. Compared to placebo, data shows scarce evidence of its efficacy up to 3 months, and suggests no difference at 6 months. However, future RCTs could present HA as an alternative to MPA for short-term symptom relief.