Carpal tunnel syndrome (CTS) is the most frequent entrapment neuropathy, affecting approximately 3% to 6% of the general adult population. It is notably more common in women, with a peak incidence between 40 and 60 years of age. Factors such as obesity, diabetes, and manual labor involving high-force or high-vibration tasks are significant contributors. The pathology is caused by compression of the median nerve in the carpal tunnel, resulting in venous congestion, nerve ischemia, and focal demyelination. Patients commonly present with sensory disturbances in the distribution of the median nerve—specifically the thumb, index finger, middle finger, and the radial half of the ring finger. Symptoms often include nighttime pain or numbness that prompts the patient to "shake out" their hands for relief, alongside a weak grip and potential thenar muscle atrophy. Standard conservative management includes neutral-position wrist splinting, activity modification, and corticosteroid injections. Surgical release, which has a success rate of 70 - 90%, is reserved for severe or refractory cases.

To evaluate the efficacy of wrist splints, researchers randomized 142 patients with primary idiopathic CTS to receive either a rigid wrist splint (n=70) or a placebo soft bandage (n=72) designed to allow a full range of motion. Treatment lasted 6 to 10 weeks, with outcomes assessed at 12 weeks and 1 year. The co-primary outcomes were the change in a six-item CTS symptom score (range 1-5, with higher scores being worse) at 12 weeks and the proportion of patients undergoing surgery at 1 year. At 12 weeks, the rigid splint group improved from a mean baseline of 2.81 to 2.45, while the placebo group improved from 2.80 to 2.52 (adjusted mean difference, 0.08; P=0.478). At one year, surgery rates were comparable, occurring in 57.1% of the splint group and 51.4% of the placebo group (Relative Risk: 1.10; 95% CI, 0.81-1.48).

This small study calls into question the efficacy of wrist splinting for CTS. Despite its widespread recommendation in clinical guidelines, the lack of improvement in symptoms or reduction in the need for surgical intervention suggests that the benefits of splinting may be influenced by the placebo effect and/or the condition's natural history. Despite its lack of proven benefit, providers may continue to recommend splinting, as some patients improve with time and the perception that their condition is being treated.

• Wrist Splinting versus a Placebo Soft Bandage for Carpal Tunnel Syndrome, NEJM Evid (2026) [PubMed abstract]
• Orthopedic studies