Carpal tunnel syndrome with diabetic polyneuropathy weakens hand dexterity in T2D

The combination of diabetic polyneuropathy (DPN) and carpal tunnel syndrome (CTS) lowers grip and pinch strength, as well as tactile sensation and hand dexterity among patients with type 2 diabetes (T2D), a new study has found.

The researchers enrolled 161 T2D patients (mean age 58.4±12.8 years, 85 men), whose grip and pinch strengths, tactile sensory thresholds, and CTS were measured through physical examinations and electrodiagnostic testing. Hand dexterity was evaluated using the Purdue pegboard test.

Forty-three participants had electrophysiologically confirmed CTS, yielding a prevalence rate of 26.7 percent. Most of the CTS cases were moderate in severity (n=29; 67.4 percent), and only three patients (6.9 percent) had severe CTS. DPN was fairly common, which was present in 112 patients, corresponding to 69.6-percent prevalence rate.

Thirty-six (22.4 percent) patients had both CTS and DPN. Logistic regression revealed that patients with DPN were nearly five times as likely to develop CTS (odds ratio, 4.755, 95 percent confidence interval [CI], 1.543–14.651; p=0.007).

Dynamometer readings showed that the presence of CTS led to lower grip and pinch strength. Tactile sensory was likewise compromised with CTS, though the magnitude of effect was too small to be clinically meaningful. On the other hand, DPN seemed to elevate tactile sensory in both the second and fifth fingers; DPN had no impact on grip and pinch strength.

Patients with both CTS and DPN had significantly weaker grip strength and tactile sensation compared with other disease combination subgroups.

Similar results were observed for overall hand dexterity. Participants with either CTS or DPN tended to score lower on the Purdue pegboard, while those with both conditions scored the lowest.