Microanatomical And Histological Studies On The Fascicular Group To The Intrinsic Muscles Of Hand In Median Nerve And Three-Dimensional Imaging Reconstruction Of Its Fascicular Groups

The key of the nerve recovery is to find the right way for the axis-cylinder so that the effective appararus may recover their function .As one of the most effective methods to treat the nerve root avulsion at present, the selecting nerve transfer needs to select profitable nerve fascicules groups.The attempt to perform nerve transfer to recover the function of the intrinsic muscles of hand demands the detailed knowledge about the fascicular group to the intrinsic muscles of hand in the nerve trunk. For this purpose, the microanatomical and histological studies had been performed using cadaveric specimens on the arrangement, localization and the histological feature of the fascicular groups to the intrinsic muscles of hand in the Median nerve trunk . The 3D image of the fascicles groups in median nerve was reconstructed using the computer technique to supervise the microsurgical repair of the injuries of brachial plexus and median nerve and to provide morphological base for the functional recovery of the intrinsic muscles after root avulsion of brachial plexus and the image may be used in teaching and studying.Materials and Method1.12 cadaveric upper extremities (half right and half left, all male adults) recently emballmed by the formalin were obtained. The median nerve and its branches were exposed by the deep muscular division and median nerve (govern the intrinsic musclesof hand especially) was identified. The median nerve in the forearm (from styloid process of radius to medial epicondyle of humerus) was divided equally into sixteen segments.and the nerve in upper arm (from styliod process of humerus to inferior boarder of teres major muscle) into eight segments. The nerve specimens were infused topically with 10% acetic acid and contradissection of individual fascicular groups was done by tracing their terminal branches. Observations and records were made in each segment about the arrangement,localization, and distribution of the fascicular group to the intrinsic muscles of hand in the nerve trunk.. It was observed that how it crossed and mixed with other fascicular groups . During the dissection other fascicular groups might be involved if it was difficult to dissct because of crossing and mixing with the fascicular group to the intrinsic muscles of hand. And their different forms of fibers were recorded. The diameters of the nerve trunk and of the fascicular group to the intrinsic muscles of hand were measured. Their area and the distribution range of the fascicles group to the intrinsic muscles of hand were calculated.(As others branches were very thin so we took Thenar muscles branches as the intrinsic muscles branches of hand of median nerve).2. Another 6 fresh and fresh-frozen human cadaver (male adult) upper extremities amputated at the level of the shoulder joint were obtained. Median nerve and its branches were exposed and divided according to the same standard as stated in part one. Two sets of segmental specimens were got from each divided segment and their directions were marked by ink. One was fixed in 10% formalin solution dispensed by PBS for 1 hour, then put in PBS and kept in refrigerator at 4C for 24 hours .And then 15um-thick crossing sections were cut by cryoultramicrotome. All slides were stained according to the AchE histochemical technique of Kamovsky-Roots (to distinguish motor nerve fiber from sensory fiber). According to the result of staining combined with the microdissection and the order of different branches branching off the nerve trunk, the distribution of individual functional fascicular group on the cross-section could be known. The other sets of specimen was fixed in formalin. The 7um-thick routine waxed crossing sections were made and stained according to the myelin technique of Loyez. These histological sections were analyzed by using IAS.For each histological section,mylinnated nerve fiber densities and its cross areas and areas of the nerve trunkwere measured and calculated. Then the numbers of the myelinated nerve fiber, the proportion of nerve fiber and con...