Efficacy of local injection therapy versus wrist splinting in moderate idiopathic carpal tunnel syndrome: the results of a randomized clinical trial

Abstract

Background. Carpal tunnel syndrome is the most common compression mononeuropathy. The choice of the preferred conservative treatment method is still relevant, especially for the patients with the moderate severity of the disease. Objective: to perform a comparative study of the effectiveness of local injection therapy and wrist splinting in idiopathic moderate carpal tunnel syndrome; to assess the duration of the clinical effect in the follow‑up period to 6 months. Materials and methods. The study included 105 cases of moderate idiopathic carpal tunnel syndrome. Patients were randomized to 2 groups depending on the treatment method: the main group (n = 54) received 1 or 2 ultrasound‑guided injections with glucocorticosteroid (betamethasone 5 mg + 2 mg/1.0 ml) and lidocaine 2 % 1.0 ml into the carpal canal; the control group (n = 51) was assigned wrist splinting at night for 1 month. The primary criterion for therapy effectiveness was evaluation by clinical scales (SSS, FSS, LANSS, Visual Analogue Scale) after 1 month from the treatment initiation. A secondary criterion for the therapy effectiveness was the assessment of changes in electrophysiological and neurosonographic parameters.Results. The scores for SSS, FSS, LANSS and Visual Analogue Scale were significantly lower at 1 month in the injection therapy group than in the splinting group (p <0.0001). A significant change in the electrophysiological parameters of the median nerve (a decrease the distal motor and sensory latency, an increase in the Mand S‑response amplitude, an increase in sensory conduction velocity on the hand) and a significant decrease in the cross‑sectional area of the median nerve at the level of the pisiform bone was noted only in the local injection therapy group. The average duration of the local injection therapy clinical effect surpassed the splinting one and reached 4 months.Conclusion. After 1 month from the start of the treatment, the local injection therapy demonstrated a higher clinical efficacy compared to the wrist splinting, the average duration of the effect reached 4 months. This conservative treatment method is preferred for the patients with moderate idiopathic carpal tunnel syndrome.