Evaluation of the dynamics of sensory improvement in the hand after surgical treatment of carpal tunnel syndrome.

BACKGROUND AND PURPOSE: The aim of the study was to evaluate the dynamics of improvement of tactile sensory threshold and two-point discrimination in fingers innervated by the median nerve after surgical treatment of carpal tunnel syndrome (CTS), to assess differences between improvements of both aforementioned sensory measures, as well as to estimate the time taken to achieve ultimate sensory improvement in the hand. MATERIAL AND METHODS: The study included 87 patients (78 females and 9 males) operated on at the Department of Traumatology and Hand Surgery, Medical Academy in Wroclaw between July 2002 and August 2004 because of carpal tunnel syndrome. Mean age of patients was 51.8 years. The study included evaluation of tactile sensory (pressure) threshold and two-point discrimination. Measurements were performed seven times in each patient, that is, before the surgery, and then on the second, fifth and tenth postoperative day as well as one, three and six months after the surgery. RESULTS: There were only minor differences in improvement of tactile sensory threshold and two-point discrimination between particular fingers, but in each case less favourable results were achieved in the thumb and the middle finger and the best results in the ring finger. Over time the observed degree of sensory improvement decreased, and during the last follow-up mean values of tactile sensory threshold and two-point discrimination in each of the studied fingers were within the normal range. CONCLUSIONS: After surgical treatment of CTS normalisation of two-point discrimination occurs earlier than normalisation of tactile sensory threshold. The highest degree of improvement of two-point discrimination is observed during the first two days after surgery, while the highest degree of improvement of tactile sensory threshold is noted between the 10th and 30th postoperative day. No further significant improvement of tactile sensory threshold or two-point discrimination is observed following an initial period of three months after surgery.