Carpal Tunnel Syndrome (CTS) is one of the most common peripheral neuropathies affecting the wrist, characterized by compression of the median nerve. This condition results in pain, numbness, tingling, and weakened grip in the affected limb. Various factors such as obesity, diabetes, repetitive stress injury, rheumatoid inflammation, pregnancy, and genetic predisposition increase the risk of CTS. Typically, CTS affects individuals between 40 and 60 years old, with women being twice as likely to develop the condition as men.
Vitamin D and Its Importance
Vitamin D, a fat-soluble vitamin, plays a crucial role in regulating calcium and phosphorus metabolism and supporting immunologic function. It is essential for endocrine, cardiovascular, skeletal, and skin health and possesses metabolic, antioxidant, and anti-inflammatory properties. Deficiency in vitamin D has been linked to increased inflammation and the severity of various neuropathic pain syndromes, including CTS.
Study Overview
A recent study investigated the impact of vitamin D supplementation on CTS symptoms. The study involved 14 female participants with CTS and low vitamin D levels from two centers. None of the participants had taken vitamins for six months prior to the study or had a history of medical or surgical treatment for CTS. The participants were randomized to receive either corticosteroid therapy alone or corticosteroids combined with vitamin D supplementation.
Key Findings
The study found that combining vitamin D with corticosteroid therapy improved pain relief, reduced symptom severity, and positively affected certain electromyography (EMG) parameters. Here are the main results:
Phalen Test Positivity: In the intervention group, Phalen test positivity decreased from 100% at baseline to 75% at three months. In the corticosteroid-only group, positivity rates dropped from 67% to 33%.
Tinel Test Positivity: Tinel test positivity in the corticosteroid-only group decreased from 50% at baseline to 33% at three months. In the vitamin D supplementation group, positivity reduced from 88% to 75%.
Pain Relief and Symptom Severity: Pain relief was more significant in the intervention group, correlating with increased vitamin D levels. Both groups showed reduced symptom severity without significant improvement in functional state.
EMG Improvements: The intervention group showed improvements in motor latency of the median nerve and sensitive driving speed.
Conclusions
The study corroborates previous findings that vitamin D deficiency is associated with an increased risk and severity of CTS symptoms. Supplementation of vitamin D in CTS patients with low levels of the vitamin appears to alleviate pain and reduce nerve hypersensitivity. Vitamin D achieves these effects by suppressing L-type calcium channel expression and upregulating vitamin D receptors and their antioxidant activity.
The study also highlighted that both the Tinel and Phalen tests, typically used for diagnosing CTS, could also monitor treatment progress, demonstrating clinical improvements in both treatment groups.
Future Directions
Larger studies with extended follow-up periods and additional evaluation tools are needed to further validate and expand these findings. The current study provides a promising foundation for considering vitamin D supplementation as part of the management strategy for CTS, particularly in patients with documented vitamin D deficiency.