Extensive mobilization of injured peripheral nerves is often required to allow a tension-free repair. The purpose of this study was to determine the effect of surgical mobilization and division on intraneural blood flow and oxygen tension in a rat sciatic nerve model. The right and left sciatic nerves were exposed in male Lewis rats Four experimental groups were studied: 1) nerve in situ/intact (n=7); 2) nerve mobilized and intact (n=7); 3) nerve in situ/divided (n=7); and 4) nerve mobilized and divided (n=7). Intraneural oxygen tension and blood flow were measured postoperatively. Mean oxygen tension (mmHg) in mobilized/intact nerves (17.47+/-4.79) was significantly lower than in in situ/intact nerves (38.32+/-5.16) [p < 0.05]. Mean oxygen tension in mobilized/divided nerves (3.10+/-1.25) was significantly lower than in in situ/divided nerves (30.30+/-6.36) [p < 0.005]. Laser Doppler flow (ml/min/100 g) in mobilized divided nerves (11.31+/-1.81) was significantly lower than in in situ/divided nerves (25.60+/-3.31) [p < 0.05]. Laser Doppler flow in mobilized/intact nerves was not statistically significantly different from in situ/intact nerves. Mobilization of the extrinsic blood supply was shown to significantly lower intraneura) oxygen tension and laser Doppler flow in mobilized intact and divided rat peripheral nerves.