Intra-operative neurophysiological prediction of upper trunk recovery in obstetric brachial plexus palsy with neuroma in continuity

Abstract

We investigated the predictive value of intra-operative neurophysiological investigations in obstetric brachial plexus injuries. Between January 2005 and June 2011 a total of 32 infants of 206 referred to our unit underwent exploration of the plexus, including neurolysis. The findings from intra-operative electromyography, sensory evoked potentials across the lesion and gross muscular response to stimulation were evaluated. A total of 22 infants underwent neurolysis alone and ten had microsurgical reconstruction. Of the former, one was lost to follow-up, one had glenoplasty and three had subsequent nerve reconstructions. Of the remaining 17 infants with neurolysis, 13 (76%) achieved a modified Mallet score > 13 at a mean age of 3.5 years (0.75 to 6.25). Subluxation or dislocation of the shoulder is a major confounding factor. The positive predictive value and sensitivity of the intra-operative EMG for C5 were 100% and 85.7%, respectively, in infants without concurrent shoulder pathology. The positive and negative predictive values, sensitivity and specificity of the three investigations combined were 77%, 100%, 100% and 57%, respectively. In all, 20 infants underwent neurolysis alone for C6 and three had reconstruction. All of the former and one of the latter achieved biceps function of Raimondi grade 5. The positive and negative predictive values, sensitivity and specificity of electromyography for C6 were 65%, 71%, 87% and 42%, respectively. Our method is effective in evaluating the prognosis of C5 lesion. Neurolysis is preferred for C6 lesions.

The natural history and management of brachial plexus birth palsy

“…It was traditionally accepted that neurolysis alone was not sufficient in regaining neurologic function [49]. However, neurolysis alone has been revisited and may be indicated in infants who show signs of recovery intra-operatively with nerve stimulation or in a subgroup of patients with >50 % nerve conduction pre-operatively [12,50]. Superior results with neuroma resection and nerve grafting compared with neurolysis have been consistently demonstrated in the literature.…”

Clinical assessment of the infant and child following perinatal brachial plexus injury

“…44 For example, the integrity of the roots can be assessed intraoperatively through the elicitation of motor- and sensory-evoked potentials. 43 As discussed above, the interpretation of EMG findings in the few months post-birth is controversial. Yet, van Dijk et al 40 found that needle EMG conducted at one month of age predicted paralysis of the elbow flexors at 3 months.…”

Early electrodiagnosis in the management of neonatal brachial plexus palsy: A systematic review

“…Only six studies had a prospective design. Most studies were completed in Europe, followed by three studies performed in Asia and South America . Three studies were conducted in the United States …”

“…All studies are prone to selection bias by including a nonrandom sample of the NBPP population. Six studies included a surgery group, five included a slow recovery or severe group, and five included NBPP children referred to a tertiary center . In two studies the population was restricted to upper trunk lesions.…”

“…Two authors used only motor NCS and EMG. None of the included studies adopted preoperative, and only one intraoperative, somatosensory evoked potentials (SEPs). Three studies performed intraoperative NCS, with Chin et al utilizing a combination of intraoperative NCS, EMG, and gross motor response to stimulation.…”