Therefore, we aimed to evaluate the effectiveness of vitamin D replacement therapy on pain, electrophysiological parameters, ultrasonographic measurement results and functional status scales in CTS patients with low serum vitamin D levels.

Introduction: Apart from its effect on bone health, vitamin D is also known to have beneficial effects on the neurological system. In studies, vitamin D levels were found to be low in patients with Carpal Tunnel Syndrome (CTS). However, studies examining the effects of vitamin D replacement on CTS are limited. Therefore, we aimed to evaluate the effectiveness of vitamin D replacement therapy on pain, electrophysiological parameters, ultrasonographic measurement results and functional status scales in CTS patients with low serum vitamin D levels. Materials and Methods: Our study was planned as an observational and analytical prospective. Vitamin D loading therapy was given to patients with serum vitamin D levels below 20ng/ml and mild-moderate CTS detected by electroneuromyography (ENMG). Patients with vitamin D levels above 20 ng/ml after 8 weeks were included in the study. Each patient was given a rest splint and exercise program. Patients were evaluated before and 3 months after treatment with electrophysiological, ultrasonographic, VAS, pinch-grip strength, two-point discrimination, monofilament test and Boston symptom severity scale.

Inclusion Criteria:

• 18-70 years old male or female gender
• Those with mild to moderate CTS according to ENMG,
• Vitamin D level <20.

Exclusion Criteria:

• Severe CTS according to ENMG
• Thenar region atrophy
• diabetes mellitus,
• rheumatoid arthritis,
• hyperthyroidism,
• hypothyroidism
• Traumatic nerve injury, history of surgery
• Polyneuropathy
• Pregnancy
• Severe psychiatric illness
• Poor orientation and cooperation,
• Injection (corticosteroid, ozone, stem cell…) applied for CTS treatment within 3 months