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Axonotmesis is a disruption of nerve cell axon, with Wallerian degeneration occurring below and slightly proximal to the site of injury.〔Otto D.Payton & Richard P.Di Fabio et al. ''Manual of physical therapy''. Churchill Livingstone Inc. ISBN 0-443-08499-8〕 If axons and their myelin sheath are damaged, but Schwann cells, the endoneurium, perineurium and epineurium remain intact, it is called axonotmesis. Axonotmesis is usually the result of a more severe crush or contusion than neuropraxia.〔http://www.medstudents.com.br/neuroc/neuroc4.htm〕 In axonotmesis, the proximal section is repaired by creating a sprout with its growth cone, but in the distal section occurs axonal degeneration. The rate of outgrowth of regenerating nerve fibers is about 1 mm to 2 mm per day, so that the recovery of conduction to a target structure depends on not only regrowth into the appropriate endoneurial tube (endoneurium), but also on the distance involved.〔Carol Mattson Porth. ''Pathophysiology: concepts of altered health states''. Publisher: Lippincott. Third Edition. ISBN 0-397-54723-4〕 ==Assessment== A nerve contains sensory fibers, motor fibers, or both. Sensory fibers lesions cause the sensory problems below to the site of injury. Motor fibers injuries may involve lower motor neurons, sympathetic fibers, and or both. Assessment items include: * Sensory fibers that send sensory information to the central nervous system. * Motor fibers that create the contraction of skeletal muscle. * Sympathetic fibers that innervate the skin, and blood vessels of the upper and lower limbs. In assessment, sensory-motor defects may be mild, moderate, or severe. Damage to motor fibers results in paralysis of the muscles. Nervous plexus injuries create the more signs and symptoms from sensory-motor problems (such as brachial plexus injuries). In these cases, the prognosis depends on the amount of damage and the degree of functional recovery. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Axonotmesis」の詳細全文を読む スポンサード リンク
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