[Changes of the distribution of sensory disturbances and paresthesiae after carpal tunnel release]

Evaluation of changes of sensory disturbances, distribution of paresthesiae, and withdrawal of symptoms within 12 months after carpal tunnel release.

Thirty-nine patients with carpal tunnel syndrome (CTS) were evaluated for distribution of sensory disturbances. Two-point discrimination and filament testing were measured. The results were semi-quantitatively expressed as a sensory index. Distribution of paresthesiae were recorded on the whole hand, wrist and forearm. All patients completed the Levine questionnaire. Patients were assessed before the operation and at 3, 6 and 12 months after surgery. In all cases carpal tunnel was released by double incision open technique.

Sensory index for two-point discrimination fell from initial value of 1.7 to 1.4 at 3 months, and to 1.2 at 6 months and 1 year. Index for filament testing decreased from initial 2.5 to 1.8 at 3 months, 1.5 at 6 months, and 1.7 at 1 year. Subjective patients' satisfaction measured by symptomatic part of the Levine questionnaire improved significantly within first 6 months after surgery. Paresthesiae were initially experienced on middle fingertip in 90% of patients, on index fingertip in 80% and on thumb/annular fingertips in 70%. More than 50% patients complained of these symptoms to be present on little finger and 20% on the dorsal aspect of the fingers/hand. At 3 months less than 30% of the patients experienced paresthesiae on fingertips I-IV and 15% on little fingertip. At 1 year, 10% of patients still complained of paresthesias on middle and little fingertips.

Sensation improves statistically significantly within first 6 months after surgery, similarly to subjective patients' satisfaction assessed by the Levine questionnaire. Experience of paresthesiae in patients with CTS is not confined to the distribution of median nerve, although they are present most frequently at index and middle fingertips.