Clinical and electrophysiological analysis of brachial plexus nerve damage following childbirth

Objective To investigate the clinical and electrophysiological findings of brachial plexus nerve damage following childbirth .Methods 25 cases were summarized,in which the motor and sensory conduction velocity of nerves including median ulnar radial musculocutaneous axillary and suprascapular nerves were studied,F-wave were analyzed too. The pathological spontaneous electric activities and the pattern of motor unit recruitment of muscles were observed with the concentric needle electromyographic examinations,in which muscles containing abductor pollicis brevis,abductor digiti minimi,extensor digitorum,biceps brachii,bicep brachii,deltoid,supraspinatus. Results Of 25 patients there were 16 males and 9 females,involving male more than female(16/9).Abnormalities were noted in 84 out of 106 motor nerves (79%) and in 52 out of 70 sensory nerves (70.5%);Eight out of 25 F-wave latencies prolonge (24%).At least two localization fibrillation potentials and/or positive sharp waves occurred in 64 out of 126 resting muscles. The motor unit active potentials disappeared during maximal voluntary contraction in 54muscles and the recruitments deceased in 20 muscles. Conclusion The electrophysiological studies were of much significance in evaluating injury nerve,nature,severity and prognosis.