Pressure perception in the normal lower extremity and in the tarsal tunnel syndrome.

For quantitative sensory testing to be useful for the management of peripheral nerve problems, a normative database must be developed. The Pressure-Specified Sensory Device (PSSD), a handheld instrument whose hemispherical metal probe tips are connected via a force transducer to a computer, has been found reliable and valid for the upper extremity. In the present study, the PSSD was used to measure the cutaneous pressure threshold at four lower extremity sites in 34 normal adults and in 22 patients with tarsal tunnel syndrome (6 bilateral). Each of the 28 limbs that was symptomatic for tarsal tunnel syndrome had a cutaneous pressure threshold greater than the 99% confidence limit of the age-matched controls (< or = 45 years, > 45 years of age). Screening for tarsal tunnel syndrome can be done utilizing the measurement of the two-point static-touch thresholds for pressure and distance.