25 randomized controlled trials were included in this systematic review. The purpose of this study was to evaluate the efficacy of non-surgical treatments currently available for thumb base osteoarthritis. Treatments were assessed for impact on outcomes including thumb pain and function. The results of the included studies indicated that intra-articular hyaluronate injections reduced pain over long periods of time (1 year), whereas steroid intra-articular injections and leech therapy reduced pain over shorter periods of time. Orthoses were found to decrease pain for shorter periods of time, but had no effects on hand strength and function.