Repair of the peripheral nerve gap with epineural sheath conduit to prevent muscle denervation atrophy in the diabetic rat model

Muscle denervation atrophy is a result of lower motor neuron injury, thus an early restitution of muscle stimulation is essential in prevention of atrophic changes. To evaluate the new application of naturally occurring epineural sheath conduit in repair of the peripheral nerve gap to prevent development of muscle denervation atrophy. We used the model of 20 mm sciatic nerve gap, resulting in denervation atrophy of the gastrocnemius muscle in the diabetic rats (DM type 2, n=42, Zucker Diabetic Fatty strain). We applied the epineural sheath conduit created from the autologous sciatic nerve for gap repair. Muscle atrophy was assessed with the Gastrocnemius Muscle Index (GMI) and microscopic muscle morphometry (mean fiber area) at 6 and 12 postoperative week. Muscle regeneration in the experimental group was compared to the gold-standard technique of autologous nerve grafting for the repair of created nerve gap. The GMI evaluation revealed comparable muscle mass restoration in groups with nerve repair using both epineural sheath and standard autologous nerve grafting (reaching 28 and 35% of contralateral muscle mass at 12 postoperative week, respectively, p=0.1), and significantly better restoration when compared to the negative control group (no repair, 20%, p