Background: Surgery for carpal tunnel syndrome (CTS) is effective in 80% to 90% of cases, but greater neurophysiological severity is more likely to result in chronic numbness and functional hand disability. Sensory relearning, which is based on the principles of learning-dependent cortical plasticity, has been shown to improve tactile sensibility after nerve trauma. Objective: The objective of this study was to investigate whether a sensory relearning intervention taught as an unsupervised 6-week home therapy program can improve tactile discrimination and self-reported hand function in patients with chronic sensory deficits after carpal tunnel decompression. Methods: This study is a multicentered, pragmatic, randomized, controlled trial. A total of 104 patients with chronic sensory impairment after surgical decompression for CTS were randomized to receive either a standardized 6-week home sensory relearning program (n = 52) or were allocated to the control group (n = 52). The primary outcome was the Shape-Texture Identification (STI) test. Secondary outcomes were touch threshold (Weinstein Enhanced Sensory Test), touch localization test, Moberg pickup test, and 3 subscales of the Michigan Hand Questionnaire (MHQ). All patients were assessed at baseline, 6 weeks, and 12 weeks. Results: Intention-to-treat analysis showed no statistically significant differences between the groups at 6 weeks on the STI test (adjusted mean, −0.47; 95% confidence interval [CI], −1.09 to 0.143; P = 0.129) or at 12 weeks (adjusted mean, −0.18; 95% CI, −0.78 to 0.42; P = 0.549). Similarly, differences between groups on secondary outcomes were not statistically significant, with the exception of the patient-reported subscales of the MHQ (overall hand function, activities of daily living—affected hand and both hands) at 6 weeks. The significant differences in the MHQ were retained in 2 subscales by 12 weeks. A secondary analysis found that adherence with the recommended exercise frequency and duration did not have a significant effect on the primary outcome. Conclusions: At present, there is no evidence to support the use of an unsupervised sensory relearning home program as an intervention for patients with tactile sensory and functional deficits after carpal tunnel decompression. Targeting of therapies to improve functional sensibility in this population may require alternative strategies.
