EFFECTS OF DELAYED NERVE REPAIR ON REGENERATION OF RAT SCIATIC-NERVE

The optimal time for nerve suture in transected rat sciatic nerve was investigated. The sciatic nerve on both side nerves were transected an d repaired by an epineurial suture technique 0-28 days after nerve tra nsection. The regeneration distance was measured by the sensory pinch reflex test 2-6 days after nerve repair. The initial delay period and the regeneration rate were calculated by using a new mathematical mode l. One day delayed repair was sufficient to reduce the initial delay p eriod and the largest reduction on the initial delay period was observ ed in the three day delayed repair group. The initial delay period was reduced to 0.87 days as compared to 2.31 days for nerves repaired imm ediately (controls). The seven day and ten day delayed repair had simi lar effects but they also showed a decrease of the regeneration rate. The regeneration rate was not affected except for these two time point s. The results suggest that the repair delay period can influence the initial delay as well as the regeneration rate. In our model an optima l effect was achieved on both these measures with a one or three day d elay between transection and repair.