Intra Articular Injection of Botulinum Toxin Versus Corticoids in Gonarthrosis

Knee osteoarthritis is one of the most common causes of joint pain and functional disability in the general population. Intra-articular infiltrations of corticoids are indicated for painful crisis especially if accompanied of effusion. However, this effect lasts only 2 weeks. Given the lack of effective long-term medical-infiltrative treatment, we believe that botulinum toxin type A could be used by its direct action on mediators of neuro-gene inflammation at the joint level and its indirect medullary action by retrograde migration. To date, 2 published randomized controlled trials and one unpublished Phase Ib clinical trial have shown that botulinum toxin injected intraarticularly improves pain and functionality in gonarthrosis. Dynamic Contrast Enhancement (DCE) Magnetic Resonance Imaging (MRI) demonstrated the correlation between synovial inflammation and pain in gonarthrosis in a cohort of 454 subjects. It has also made it possible, via the monitoring of synovial inflammation, to demonstrate the efficacy of treatments in patients suffering from rheumatoid arthritis in the early phase, juvenile chronic arthritis or osteoarthritis. DCE MRI perfusion therefore appears here as the technique of choice to follow the evolution of synovial inflammation after botulinum toxin injection in patients with symptomatic gonarthrosis.