Axonal regeneration and organ reinnervation are the necessary steps for functional recovery after a nerve lesion. However, these processes are frequently accompanied by collateral events that may not be beneficial, such as: (1) Uncontrolled branching of growing axons at the lesion site. (2) Misdirection of axons and target organ reinnervation errors, (3) Enhancement of excitability of the parent neuron, and (4) Compensatory activity in non-damaged nerves. Each one of those possible problems or a combination of them can be the underlying pathophysiological mechanism for some clinical conditions seen as a consequence of a nerve lesion. Reinnervation-related motor disorders are more likely to occur with lesions affecting nerves which innervate muscles with antagonistic functions, such as the facial, the laryngeal and the ulnar nerves. Motor disorders are better demonstrated than sensory disturbances, which might follow similar patterns. In some instances, the available examination methods give only scarce evidence for the positive diagnosis of reinnervation-related disorders in humans and the diagnosis of such condition can only be based on clinical observation. Whatever the lesion, though, the restitution of complex functions such as fine motor control and sensory discrimination would require not only a successful regeneration process but also a central nervous system reorganization in order to integrate the newly formed peripheral nerve structure into the prepared motor programs and sensory patterns.
Clinical Neurophysiology
Volume 122, Issue 2, February 2011, Pages 219-228
Friday, January 28, 2011
without any increase of nutritional blood flow
Techniques with effect on the sympathetic nerve system, sympathetic block or sympathectomy increase blood flow, mainly due to opening of arteriovenous shunts and without any increase of nutritional blood flow. However, some patients may benefit in terms of reduced pain.
Little evidence exists but a review from 1985 concluded that sympathectomy could be beneficial in patients with rest pain and pregangrene. It is, however, most unlikely that diabetic patients can respond as they usually have a reduced sympathetic tone in the ischemic leg.
Cardiovascular and Interventional Radiological Society of Europe / 2007
Clinical Practice in Interventional Radiology, Volume I,
Little evidence exists but a review from 1985 concluded that sympathectomy could be beneficial in patients with rest pain and pregangrene. It is, however, most unlikely that diabetic patients can respond as they usually have a reduced sympathetic tone in the ischemic leg.
Cardiovascular and Interventional Radiological Society of Europe / 2007
Clinical Practice in Interventional Radiology, Volume I,
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