Wrist flexion as an adjunct to the diagnosis of carpal tunnel syndrome.

The effects of five minutes of wrist flexion on median motor and sensory evoked potential latencies in 87 individuals were studied. Nineteen subjects had carpal tunnel syndrome (CTS) as diagnosed by increased median nerve latencies across the wrist, and 68 had values in the normal range and were assigned to the control group. A slight prolongation of up to 0.5m sec of evoked potential latencies was observed in both groups after flexion, but the differences between the two groups were not significant to establish the value of adding wrist flexion to conventional screening methods.