Dr. Rajat Gupta has been the visitor scholar in the Department of Microvascular Surgery at Chang Gung Memorial Hospital, Taiwan where he has seen the protocols and the management startegies of Dr David Chuang who is dealing with the heavy volume of Brachial Plexus injuries. Dr Rajat has inculcated these protocols and the surgical skills to high level of precision. One needs to understand the anatomy and pathophysiology of Brachial Plexusus lesions. High-energy trauma to the upper extremity and neck can cause a variety of lesions to the brachial plexus. Most common are traction injuries, in which the head and neck are moved away violently from the ipsilateral shoulder. Loss of useful function of the upper extremity is common, but early repair and reconstruction are providing far greater restoration than was possible a few years ago.
Narakas developed his rule of "seven seventies " in his experience over 18 years with 1068 patients :
Approximately 70% were motor vehicle accidents (MVAs).
Of the MVAs, 70% were motorcycles or bicycles.
Of the cycle riders, 70% had multiple injuries.
Of the multiple injuries in cycle riders, 70% were supraclavicular injuries.
Of the supraclavicular injuries, 70% had at least one root avulsed.
Of the avulsed roots, 70% were lower C7, C8, T1.
Of the 70% avulsed roots, 70% of those were associated with chronic pain
The common mechanism for traction injuries of the brachial plexus is violent distraction of the entire forequarter from the rest of the body leading to injury either proximal (preganglionic) or distal (postganglionic) to the dorsal root ganglion. A preganglionic root avulsion means that the cell bodies of the sensory nerves are pulled from the cord, diminishing the possibility of recovery or surgical reconstruction. These are differentiated from distal ruptures - postganglionic stretch injuries - in which cell bodies are still in continuity with their axons.
The head and neck are moved away violently from the ipsilateral shoulder. Upper plexus injuries (C5 and C6) usually predominate if the arm is at the side because the first rib acts as a fulcrum to direct the traction forces preferentially in line with the upper plexus. When the arm is moved violently and abducted overhead, the lower elements (C8-T1) typically are injured, as the force is directed in line with C7. A lower plexus lesion predominates when the arm is raised because the coracoid acts as a fulcrum in a similar fashion.
Surgical options include nerve (primary) and soft-tissue (secondary) reconstruction. External neurolysis alone may benefit a nerve in continuity that exhibits a nerve action potential (NAP). Postganglionic neuromas or ruptures may benefit from nerve grafting. From an overall perspective, such grafts include C5 for shoulder abduction, C6 for elbow flexion, and C7 for elbow and wrist extension.