Improvement of hand sensibility after selective temporary anaesthesia in combination with sensory re-education

Purpose: The results of nerve repair in adults are often poor. The study aim was to investigate the effect of repeated sessions of cutaneous forearm anaesthesia of the injured limb, in combination with sensory re-education on the recovery of the tactile discrimination and perception of touch/pressure in the injured hand after median or ulnar nerve repair. Methods: A prospective, randomized, double-blind clinical trial was designed. During a 2-week period, a topical anaesthetic cream (Lidocaine-PTC, n = 6) or placebo (n = 7) was applied repeatedly (twice a week) with occlusive bandage for 1 hour on the flexor aspect of the forearm of the same side of the nerve injury and combined with sensory re-education. Assessments of sensory function were performed prior to the experiment and after the fourth application of Lidocaine-PTC/placebo. The patients were evaluated again 4 weeks after the last Lidocaine-PTC/placebo session. Results: Touch perception measured with Semmes-Weinstein Monofilaments (SWM), improved significantly in the Lidocaine-PTC group (p = 0.005). In placebo group, no significant changes were seen. Two-point discrimination improved significantly only in the Lidocaine-PTC group (p = 0.005). Conclusion: This finding suggests that forearm deafferentation of injured limb in combination with sensory re-education can enhance sensory recovery after nerve repair.