Vibrotactile sense 5 years after carpal tunnel release in people with diabetes: A prospective study with matched controls

AIM: To compare vibrotactile sense, 5 years after carpal tunnel release in people with and without diabetes. METHODS: Out of 35 people with diabetes and carpal tunnel syndrome, age‐ and gender‐matched with 31 people without diabetes but with idiopathic carpal tunnel syndrome, 27 and 30 people, respectively, participated in this prolonged follow‐up. Vibration perception threshold of the index and little finger (median and ulnar nerve, respectively), 5 years after surgery, was measured at seven different frequencies (8, 16, 32, 64, 125, 250 and 500 Hz). RESULTS: Significant improvement of vibration perception threshold from 1 to 5 years after carpal tunnel release was found at 64 Hz for people with diabetes, while improvement for people without diabetes was demonstrated at several frequencies (64–250 Hz). However, both groups demonstrated a significant decrease in vibration perception threshold for the low frequencies (8–16 Hz). At 5 years, people with diabetes had significantly impaired vibration perception threshold at the index finger for high frequencies (125–500 Hz), and for nearly all frequencies (16 Hz, 64–500 Hz) at the little finger, compared to people without diabetes. CONCLUSION: After carpal tunnel release, significant mid‐term improvement of vibrotactile sense appears limited for people with diabetes, compared to a continuous improvement for people without diabetes. In addition, a decline in low‐frequency vibrotactile sense occurs for the median as well as the ulnar nerve innervated fingers. Clinical Trial Registration NCT01201109