Feasibility of Using the Gap Detection Tactility Test for Monitoring Cutaneous Sensory Deficits

Abstract

Periodic worker monitoring methods are needed for detecting cumulative trauma disorders, such as carpal tunnel syndrome (CTS), in the early stages. An experiment was conducted for studying the feasibility of using a new aesthesiometer for periodically measuring functional tactile sensitivity. It was conducted to investigate gap detection sensory threshold differences between five normal subjects and seven subjects diagnosed having CTS. The gap detection test was used because of its functional resemblance to many work-related activities. Average gap detection sensory threshold using the index finger was 0.21 mm (SD = 0.14 mm) for the normal subjects and increased 114% to 0.45 mm (SD = 0.16 mm) for the CTS subjects when finger probing was allowed. Average gap detection sensory threshold using the index finger was 1.57 mm (SD = 0.56 mm) for the normal subjects and increased 61% to 2.53 mm (SD = 0.82 mm) for the CTS subjects when finger probing was not allowed. The results suggest that people suffering from CTS may experience similar functional deficits in daily living and work activities. A strong relationship was also observed between electrophysiologic variables and the gap detection sensory thresholds when both the CTS and normal hands were pooled. This suggests that performance in the gap detection test might measure the level of median nerve function in CTS.