Duration of contact time alters cutaneous pressure threshold measurements

Semmes-Weinstein monofilaments (SWMs) are standard measures used to assess hand sensibility. The purpose of this study was to evaluate the effect of varying contact time on the measurement of cutaneous pressure thresholds. Thirty-two healthy adult subjects were evaluated with a 20-filament SWM test kit. The index finger of the dominant hand was assessed with the following four distinct monofilament contact times: 0.5, 1.5, 5.0, and 30.0 seconds. With increased duration of monofilament contact time, there was a significant increase in the cutaneous pressure threshold measures (p < 0.05). That is, to perceive a stimulus for a longer period of time, a heavier filament was required. With increasing age, significantly higher pressure thresholds were obtained particularly for the sustained contact time (>5.0 seconds). Pressure thresholds vary significantly with SWM contact time, emphasizing the importance of maintaining a consistent SWM application protocol.