Abstract
OBJECTIVE: Arthritis of the knee affects 46 million Americans. We aimed to determine the level of evidence of intraarticular knee injections in the management of arthritic knee pain. METHODS: We systematically searched PUBMED/MEDLINE and the Cochrane databases for articles published on knee injections and evaluated their level of evidence and recommendations according to established criteria. RESULTS: The evidence supports the use of intraarticular corticosteroid injections for rheumatoid arthritis (1A+ Level), osteoarthritis (1A+ Level), and juvenile idiopathic arthritis (2C+ Level). Pain relief and functional improvement are significant for months up to 1 year after the injection. Triamcinolone hexacetonide offers an advantage over triamcinolone acetonide and should be the intraarticular steroid of choice (2B+ Level). Intraarticular injection of hyaluronate may provide longer pain relief than steroid injection in osteoarthritis (2B+ Level). It can also be effective for rheumatoid arthritis knee pain (1A+ Level). However, it is only recommended for patients with significant surgical risk factors and for patients with mild radiographic disease in whom conservative treatment has failed (2B± Level). Botulinum toxin type A injection is effective in reducing arthritic knee pain (2B+ Level), and so is tropisetron (2B+ Level) and tanezumab (2B+ Level). The new agents, such as rAAV2-TNFR:Fc, SB-210396/CE 9.1, and various radioisotopes have provided various degrees of success, but their long-term safety and efficacy remains to be determined. CONCLUSIONS: We conclude that strong evidence supports the use of intraarticular knee injection as a valuable intervention in the continuum of management of arthritis between conservative treatment and knee surgeries.