Systemic Betamethasone Accelerates Functional Recovery After a Crush Injury to Rat Sciatic Nerve

Abstract

The aim of the study was to evaluate the effect of perioperatively systemically administered betamethasone on nerve recovery (within or outside a confined space) after induced nerve crush injury. The sciatic nerve of 40 adult Wistar rats was crushed. In half of the animals, the injured nerve was entrapped in a silicone tube to simulate the environment of a closed space, and in the other half the nerve was left to heal. Half of the rats in each group were treated with subcutaneous betamethasone (2 mg/kg body weight/day) during the first 24 hours, starting preoperatively, whereas the other half, the control animals, were given the same amount of physiological saline. All animals underwent preoperative and postoperative walking track analysis (toe spread [TS] and intermediate toe spread [ITS]) twice weekly for 6 weeks. For nonconfined space groups, there was no significant difference between the 2 groups (P = .052 for ITS and P = .315 for TS) during the first 2 weeks. Starting from the end of the second week, animals treated with betamethasone recovered more rapidly than did the controls (P < .001) and continued to do so until the end of the observation period. In the confined space groups, there was a significant difference between the 2 groups for ITS (P < .001) and for TS (P < .05) during the first 2 weeks. The difference continued at almost the same level of significance (P = .001) for ITS, whereas for TS, the difference disappeared after the second week. We conclude that short-term perioperative administration of betamethasone has a beneficial effect on the recovery of the injured rat sciatic nerve.