To evaluate the efficacy of intra-articular injections of botulinum toxin A (BT-A) into the painful joint diseases through a systematic review of the literature and a meta-analysis of controlled randomized trials. Indeed, intra articular therapies (corticosteroids, hyaluronic acid) have limited efficacy and run a risk of toxicity in patients with joint pain. New therapeutic options are needed to treat painful osteo-articular disease.
We searched via Pubmed, ACR and EULAR congresses and grey literature for the studies reported until June 2016 and addressing the issue of BT intra articular injections in patients with refractory joint pain. Randomized trials were included. For the meta-analysis, we compared for each study numeric rating scale (NRS) from 0 to 10 before treatment and 1 or 2 months and 6 months after, in BT-A and control group. We also compared separately low dose and high dose of BT at 1 or 2 months evaluation.
Out of 269 selected articles, 8 were analyzed and 6 studies were included in the meta-analysis involving a total of 382 patients. On the five trials comparing NRS at 1 or 2 months regardless the dose of BT, 4 trials showed a positive effect of BT compared to control on the NRS, 1 found no effect, the overall weighted mean difference (95% CI) was −1.10 (−1.62, −0.58) (P<0.0001, I2=63%). On the 4 trials with a low dose of BT (100 units) comparing NRS at 1 or 2 months, 3 trials showed significant results with a positive effect of BT-A injection compared to control on the NRS, the fourth study failed to find any effect. The overall weighted mean difference (95%CI) was −0.95 (−0.02, −1.88) (P=0.05, I2=67%). On the 2 trials using a high dose of BT (200 units) comparing NRS at 1 or 2 months, an almost zero effect of BT, with an overall weighted mean difference (95% CI) of 0.13 (−0.55, 0.81), (P=0.71, I2=0%). On the 3 trials comparing NRS at 6 months there was an overall weighted mean difference (95%CI) of −0.57 (−1.98, 0.83) (P=0.42, I2=73%).
BT-A intra-articular injections have short-term benefits with a statistically significant decrease in NRS pain score of around 1 point in patients with refractory joint pain. A decrease in the pain score was also observed at 6 months but with a non-significant result.
*Rheumatology department University hospital of Limoges, France
†Neurology department University hospital of Limoges, France
The authors declare no conflict of interest.
Reprints: Mathilde Courseau, MD, Rheumatology department University hospital of Limoges, 2 avenue Martin Luther King 87000 Limoges France (e-mail: email@example.com).
Received April 22, 2017
Accepted July 10, 2017