Comparison of End-to-End Technique, Helicoid Technique, and Modified Helicoid Weave Repair Technique in a Rat Sciatic Nerve Model: A Pilot Study

Background The gold standard for nerve repair is end-to-end (ETE) repair. Helicoid technique (HT) has also been previously described. In this pilot study, HT was compared to ETE and a modified helicoid weave technique (MHWT). In MHWT, recipient nerve is passed through rather than around the donor nerve, allowing for greater nerve-to-nerve interaction. Methods Eighteen adult male Lewis rats received a 2-cm sciatic nerve transection and were divided into three groups: ETE, HT, and MHWT. Five months later, electromyography (EMG), tetanic force of contraction, and wet weight of the extensor digitorum longus muscle were recorded in both the operated and non-operated sides. Nerve biopsies were taken proximal and distal to the site of the nerve graft for histological examination. Results One rat died following repair surgery and three rats died during the second surgery. The mean threshold of stimulation for ETE, HT, and MHWT were 183.3 µA, 3707.5 µA, and 656.6 µA, respectively. EMG analysis revealed that latency and duration are both affected by surgical repair type and injured or uninjured conditions. Threshold ratio (injured:non-injured) revealed pilot-level significant differences between HT and both MHWT (p = 0.069) and ETE (p = 0.082). Nerve biopsy demonstrated fascicles distally in all three groups. Conclusions While HT and MHWT function as a nerve repair technique, they are not superior to ETE. ETE remains the gold standard for nerve repair. While mean values were in favor of ETE, no statistical significance was attained.