A Systematic Review and Meta-Analysis of Intra-Articular Injections for Base of Thumb Osteoarthritis

Abstract Aim Current literature is equivocal surrounding intra-articular injections for the treatment of thumb base osteoarthritis (TBOA), which is reflected in national and international guidelines. This systematic review assesses the effectiveness of different intra-articular injections for TBOA on pain and functional outcomes. Method MEDLINE, EMBASE, Cochrane Central Register of Control Trials and CINAHL databases were searched from inception to April 2022. Randomised controlled trials and comparative case series which investigated an injection-based intervention with any comparator/s were included. The protocol was registered to PROSPERO (CRD42022337265). Results Fifteen studies were included in the descriptive analysis of this review, with 4 included in the meta-analysis. From the intra-articular injection therapies, hyaluronic acid (HA) in 11 studies, corticosteroid (CS) CS in 10 studies, platelet-rich plasma (PRP) in 2 studies, dextrose (DX) in 1, HA mixed with NSAID in 1 study and placebo (saline) in 3 studies. Meta-analysis of visual analogue scale (VAS) showed that there was no statistically significant improvement in pain in the short-, medium- or long-term time points between HA vs CS injection therapies. Meta-analysis of functional outcomes showed an improvement in function with HA vs CS ((standardised mean difference (SMD) −1.05, 95% CI −1.43 to −0.68)) at the long-term time point. No significant adverse effects were reported. Conclusions There is no superior type of intra-articular injection for improving pain and limited evidence for HA for improving function. The choice of injection should be based on availability, guidelines and cost-benefit analysis until further methodologically robust trials can be completed.