Assessment of Processed Porcine Extracellular Matrix as a Protective Barrier in a Rabbit Nerve Wrap Model

Nerve wrapping can improve outcomes by protecting nerves in a scarred tissue bed. Autologous tissue wraps have shown good results, but there are limitations associated with harvesting and availability. Extracellular matrix (ECM) derived from porcine small intestinal submucosa offers an attractive off-the-shelf option. This study evaluated this material as a nerve wrap. The sciatic nerves of 18 New Zealand rabbits were exposed and then wrapped, while the contralateral side served as sham control. Presence and quality of adhesions, motor conduction velocity (MCV), and histology were evaluated at 1, 2, and 6 months (n = 6 animals per time point). The quality, extent, tenacity, and overall impression of adhesions were not different from control at any time point (p = 0.18 to 0.99). MCV was also not statistically different from control (1 month, p = 0.35; 2 months, p = 0.20; 6 months, p = 0.83). Histology demonstrated that wrapped nerves were healthy in terms of myelination, density, and vascularity compared with controls. Vascularization and incorporation of the ECM material could be visualized at explants. All assessments supported the feasibility and safety of this material as a nerve wrap. Its ability to function as a protective barrier has strong implications for clinical use in trauma and/or recurrent compression neuropathies.