Time zero nerve gap created by rat sciatic nerve transection

Gaps following traumatic nerve transection can be overcome by nerve mobilization or by nerve grafting. Excessive tension across a nerve repair is thought to be detrimental to nerve healing leading many surgeons to perform nerve grafting in the setting of even modest tension across a nerve repair. Fresh nerve transections typically result in a nerve gap from the elastic recoil of the nerve itself. The size of the nerve gap created by a fresh transection of the rat sciatic nerve has previously not been quantified. The goal of this study was to measure the acute nerve gap produced by rat sciatic nerve transection. The average rat sciatic nerve gap size following transection was 4.0 mm, with a range of 2–6 mm. The average nerve diameter was 2.0 mm, with a range of 1.0–3.0 mm. Immediately following transection of the rat sciatic nerve, a gap equal to twice the diameter of the nerve is created. This gap is produced by the elastic recoil of the nerve.