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 one 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.

This study did not reveal evidence that c-RFA of the lateral branches provides longer relief of sacroiliac joint pain as compared with t-RFA.

Editor’s Perspective What We Already Know about This Topic What This Article Tells Us That Is New Background Sympathetic dysfunction may be present in complex regional pain syndrome, and sympathetic blocks are routinely performed in practice. To investigate the therapeutic and predictive values of sympathetic blocks, the authors test the hypotheses that sympathetic blocks provide analgesic effects that may be associated with the temperature differences between the two extremities before and after the blocks and that the effects of sympathetic blocks may predict the success (defined as achieving more than 50% pain reduction) of spinal cord stimulation trials. Methods The authors performed a retrospective study of 318 patients who underwent sympathetic blocks in a major academic center (2009 to 2016) to assess the association between pain reduction and preprocedure temperature difference between the involved and contralateral limbs. The primary outcome was pain improvement by more than 50%, and the secondary outcome was duration of more than 50% pain reduction per patient report. The authors assessed the association between pain reduction and the success rate of spinal cord stimulation trials. Results Among the 318 patients, 255 were diagnosed with complex regional pain syndrome and others with various sympathetically related disorders. Successful pain reduction (more than 50%) was observed in 155 patients with complex regional pain syndrome (155 of 255, 61%). The majority of patients (132 of 155, 85%) experienced more than 50% pain relief for 1 to 4 weeks or longer. The degree and duration of pain relief were not associated with preprocedure temperature parameters with estimated odds ratio of 1.03 (97.5% CI, 0.95–1.11) or 1.01 (97.5% CI, 0.96–1.06) for one degree decrease (P = 0.459 or 0.809). There was no difference in the success rate of spinal cord stimulation trials between patients with or without more than 50% pain relief after sympathetic blocks (35 of 40, 88% vs. 26 of 29, 90%, P > 0.990). Conclusions The authors conclude that sympathetic blocks may be therapeutic in patients with complex regional pain syndrome regardless of preprocedure limb temperatures. The effects of sympathetic blocks do not predict the success of spinal cord stimulation.

No abstract