Louisville Medicine Volume 69, Issue 2 - Page 24



The practice of medicine is indeed a humbling experience . Decades ago , after having gained experience in various aspects of neurology , I used to believe that I could diagnose even the most complex disorders and manage most of them . One case that brought me down to the ground and taught humility was that of a 20-year-old who sustained a serious injury to his right brachial plexus after being thrown off from his motorcycle . His parents brought him for detailed evaluation a month after the injury . From clinical and electromyographic assessment , it appeared that the injury involved all three trunks of the brachial plexus . My neurosurgical colleague agreed to go ahead with the time-consuming procedure of using the patient ’ s sural nerve as graft to reconnect the injured portions of the brachial plexus . I saw him three months after the surgery ; it was disappointing to see no reinnervation even in the most proximal muscles like the deltoid . He did not turn up for the next scheduled EMG and I was totally shaken to learn that he took his life out of despair .

In the context of neurotrauma , next to the brain and the spinal cord , brachial plexus injuries lead to most devastating morbidity . I can recall many such patients and one common scenario is pan-plexus injury causing the so-called flail arm ; often the first statement by the patient is “ I wish you could cut off this useless arm .” The frustration caused by sudden loss of function , especially in the dominant upper extremity can be severe enough to trigger suicidal thoughts as in the patient I described earlier . In the next few paragraphs , I will discuss various aspects of trauma to brachial plexus and the few new treatment options .
The brachial plexus is a highly complex structure and a nightmare to the medical student and the neurology resident alike . Questions like “ What muscles are innervated by the upper trunk of the brachial plexus ? What are the sensory branches from the cords ? What is the first motor branch ? What is a prefixed brachial plexus ? How do you distinguish root avulsion from injury to the trunk ?” are not uncommon in board examinations . Neurology examiners almost always have vignettes pertaining to the brachial plexus , often providing glee to the examiner and causing gloom to the examinee .
What causes brachial plexus injury ? During my neurology residency , almost half a century ago , the most common cause used to be perinatal injury , usually from the use of forceps during labor . The reported incidence is between 0.42-5.1 per 1,000 live births , 1 providing a gold mine for the attorneys . Statistical data indicates that 75 % of infants recover completely within the first month ; 25 % have permanent impairment . In the later years , I saw an increasing number of injuries from motor vehicle accidents ; especially being thrown from a motorcycle and landing in a way that causes forcible movement of the shoulder down and away from the neck resulting in upper plexus palsy . More recently , an alarming number of gunshot injuries to the brachial plexus occur , a sign of the epidemic