Tactile sensitivity in systemic sclerosis. Assessment of two-point and circle discriminations of the digit.

The two-point and circle discriminations of the third digit of the hand were studied in 25 patients with systemic sclerosis as compared to 25 healthy controls matched for sex and age. 1 patient (4%) had diminished two-point discrimination = 10 mm and other signs of neuropathy. Mean two-point discrimination in the controls was 3.44 mm, SD 1.00 mm, and mean + 2 SD 5.44 mm. The normal two-point discrimination of the pulp of the digit could be defined as less than or equal to 5 mm. The circle discrimination was not diminished in any case. 8 patients (32%) complained of numbness of the digits, but examinations revealed neuropathy in only 1 case. Determination of two-point discrimination of the digit is recommended to screen neuropathy in systemic sclerosis.