Background and objectives: Carpal tunnel syndrome (CTS) is caused by compression of the median nerve as it passes through the wrist. It can be treated with both surgical and non-surgical methods. Botulinum toxin type A has been used in the treatment of spasms, dystonia, migraine relief and myofascial pain. This study is aimed at evaluating the safety and tolerability of botulinum toxin type A in carpal tunnel syndrome. Methods: We conducted an open-label, prospective study using 30 units of onabotulinum Toxin A (Botox[Formula: see text]), injected into the carpal tunnel using the in-plane ultrasound-guided ulnar approach. We used the verbal numeric rating scale (VNRS) to assess changes in pain and paraesthesias both 4 and 12 weeks following the injection. All adverse effects were recorded. Results: A total of 18 patients with 22 mild-moderate idiopathic CTS were included in the study. A total of 14 women and 4 men with a mean of age [Formula: see text] years. Botulinum toxin A was well tolerated and only one patient reported temporary subjective weakness in his/her hand muscles. Both at 4 weeks and 3 months following the injection we observed a 63.6% subjective improvement in the patients’ level of pain and paraesthesias, with no statistical significance ([Formula: see text]). Conclusion: Our study shows the effects of botulinum toxin in relieving pain and paraesthesias in carpal tunnel syndrome with moderate symptoms. The use of an in-plane ultrasound approach for its injection into the carpal tunnel adds value and safety to the procedure, and, based on our experience, is well tolerated and safe. Further studies are required to confirm these results and define optimal doses of botulinum toxin.
The effect of botulinum toxin type A injection in decreasing intratunnel tendon tension in carpal tunnel syndrome: a randomized controlled trial for efficacy and safety