A novel approach of local corticosteroid injection for the treatment of carpal tunnel syndrome.

The objective of the study was to compare the favorable response rate, time duration, and pain level of local corticosteroid injection using a novel approach for the treatment of carpal tunnel syndrome vs a classic approach. Patients with symptomatic carpal tunnel syndrome of less than 1-year duration were randomized for local corticosteroid injection using either the classic approach or a novel approach. In our approach (novel), we used a 29 gauge x 1/2-in. needle and a 1-ml insulin syringe containing 12 mg of methylprednisolone mixed with 0.15 ml of lidocaine 2%, and the site of the injection was 2-3 cm distal to the middle of wrist crease. In the classic approach, we used a 25 gauge x 3-cm needle and a 2-ml syringe injecting 35 mg of methylprednisolone mixed with 0.5 ml of lidocaine 2%, 3-4 cm proximal to the wrist crease and just ulnar to the tendon of the flexor carpi radialis muscle. Response rate was evaluated 1, 3, 6, and 12 weeks after the injection, and also the duration of time of the procedure and the level of pain using the visual analogue scale were compared between the two groups. Forty-two patients signed the consent form, and all of them completed the study [21 patients in the classic approach group (group 1) and 21 patients in the novel approach group (group 2)]. The favorable response rates were 100, 81, 71, and 57% in group 1 and 100, 71, 67, and 57% in group 2 after 1, 3, 6, and 12 weeks, respectively. There was no significant difference in the favorable response rate between the two groups (p=0.468, 95% CI=-12-31%, after 3 weeks). The average duration of time of the procedure in group 1 was 26.71+/-32.83 s compared to 8.48+/-1.123 s (p=0.021) in group 2. The average grade of pain expressed by the patients in group 1 was 4.38+/-1.523 compared to 3.62+/-1.071 in group 2 (p=0.065). In conclusion, local corticosteroid injection using the novel approach for the treatment of carpal tunnel syndrome is helpful, and the favorable response rates are comparable to those using the classic approach after 1, 3, 6, and 12 weeks. The novel approach is much less time consuming and is not more painful.