الفهرس | Only 14 pages are availabe for public view |
Abstract Peripheral nerves are specialized tissues that transmit an electric current, receiving sensory input, sending motor commands, as well as autonomic in and out flow. They consist of neural and non-neural tissues. When injured they have the capacity to regenerate in orchestrated events occurring at the site of injury, distal, proximal segments and terminal receptors. Peripheral nerve injuries have a devastating outcome if not managed properly. An insensate immobile limb may encounter many problems to the patient requiring amputation. The primary nerve repair is the preferred technique wherever possible. The autogenous nerve graft is still the gold standard in overcoming a nerve gap. Nerve transfer or ETSN are two different techniques of nerve repair used particularly in specific situations of peripheral nerve injuries. Several experimental works and clinical application were done on both techniques. The main advantage of nerve transfer is end to end repair, although there is complete sacrification of the donor end organ. In ETSN the down grading of the donor nerve is usually negligible, but the functional outcomes in previous studies are controversial especially when compared to the end to end technique. Probably this varied from hand to hand and according to the donor nerve size. Other many issues about ETSN are still unclear and debatable as the sensory and motor sprouting, and the prerequisite for donor axonal injury.The aim of this work was to compare the efficacy of motor nerve transfer and end to side neurorrhaphy either by mixed nerve or motor nerve. Sixty Wister rat weighting 200-300 g were divided into six groups. group I is normal control, group II was denervated control where the Cranial tibial muscle (CTM) was denervated by cutting the peroneal nerve, In groups III ETS between the peroneal nerve and side of the tibial nerve (mixed nerve) was created, while in group IV an ETE of the peroneal nerve (mixed nerve) was done. The ETE between motor branch of the lateral head of gastrocnemius muscle (LGCM) and peroneal nerve (mixed nerves) was performed in group V, and in group VI an ETS between Peroneal nerve (mixed nerve) and motor branch of LGCM (motor nerve) was created. After 60 and 120 (time of sacrification) days walking track analysis and peroneal functional index (PFI), mid leg circumference, EMG, forced muscle contraction (FMC), muscle weight, muscle width, and histomorphometry of the nerves and muscles were done. In all the groups the CTM was examined, while the LGCM only examined in groups I, III, V and VI to evaluate the effect on the muscle supplied by the donor nerve. The results of the different evaluation methods revealed that, the four experimental groups fell in between the normal control and denervated contro groupsl. The best experimental group was IV (ETE with mixed nerve) and the worst was group VI (ETS with motor nerve). Comparing the CTMs in groups III (ETS with mixed nerve) and V (ETE with motor nerve) showed no significant difference in all the parameters. In group V (ETE with motor nerve) the muscle supplied by the donor nerve was completely lost, while in group III the muscle (LGCM) supplied by the donor nerve showed no significant difference from the control muscles. These results gave the advantage of ETS with mixed nerve over the ETE with motor nerve (nerve transfer), due to donor muscle preservation. |