gms | German Medical Science

Objectives/Interrogation: Tension-free epineural repair is the accepted treatment of a peripheral nerve injury. Neuroma formation and scarring to surrounding structures can adversely affect outcome of repair. Collagen nerve wraps (NeuraWrap, Integra Life Sciences, Plainsboro, NJ) are available for clinical use to cover the site of repair and potentially minimise these complications. We report a retrospective clinical series of 2 groups of forearm nerve repair- direct neurorraphy with and without a collagen wrap. The objective is to detect any difference between the two groups in clinical outcome and ultrasound appearance of the repaired nerve.

Methods: A retrospective review of our institutional records revealed 45 patients who underwent primary end-end forearm nerve repair. 13 patients (16 nerves) returned for follow up evaluation. There were 10 primary repairs (3 Median, 3 Ulnar, 3 Superficial Radial Nerve and 1 posterior cutaneous nerve) and 6 repairs (4 Median, 1 Ulnar and 1 superficial radial nerve) augmented with wrap in the study. Clinical examination was done to determine sensory recovery and grip strength and patient reported outcome was measured using the DASH score. Circumference and cross-sectional area of the nerve at the repair site was measured using ultrasound performed by a radiologist who was blinded to the type of repair performed.

Results and Conclusions: 3 of the 10 patients who had nerve repair without wrap had ongoing analgesic requirements whilst none of the 6 patients who had a repair with collagen wrap needed analgesia. There was no clinically significant difference on clinical examination (Sensation testing - no wrap 2.20 vs wrap 2.67 and grip strength - no wrap 26.99 vs wrap 30.68) or DASH score (no wrap 24 vs wrap 24.6). Circumference and cross-sectional area of the repair site on ultrasound when compared to the contralateral nerve was bigger for primary repair compared to wrap suggesting that the using of wrap reduces neuroma formation (Circumference - no wrap 302% bigger vs wrap 256% bigger). The sample size was too small to reach statistical significance.

The study has demonstrated that the use of a nerve wrap leads to a smaller diameter of the repaired nerve and less pain and therefore decreased neuroma formation. Further prospective studies with larger numbers are required to demonstrate if this translates to improved clinical outcomes.