Clinical-electromyography correlation in infants with obstetric brachial plexopathy

Area of Science:

• Pediatric Neurology
• Neurophysiology
• Neonatal Care

Background:

• Obstetric brachial plexopathy (OBP) is a significant concern in neonates.
• The utility of needle electromyography (EMG) for assessing OBP in infants is debated.
• Accurate assessment is crucial for guiding treatment and predicting outcomes.

Purpose of the Study:

• To evaluate the correlation between needle EMG findings and clinical assessments in infants with OBP.
• To determine the reliability of EMG in estimating muscle recovery in this population.
• To identify discrepancies between EMG and clinical evaluations.

Main Methods:

• EMG was performed on 41 infants (42 arms) aged 3-12 months with severe OBP.
• EMG interference patterns were correlated with clinical assessments of key upper limb muscles.
• Specific muscles assessed included infraspinatus, deltoid, biceps, triceps, and extensor digitorum communis.

Main Results:

• Motor unit potentials were consistently present; abnormal spontaneous activity was infrequent in proximal muscles.
• EMG showed poor correlation with clinical assessment, except for the extensor digitorum communis.
• EMG scores were higher than clinical evaluations for infraspinatus, deltoid, and biceps.
• Respiratory synkinesis was observed in 45% of affected arms, potentially involving C5-T1 innervations.

Conclusions:

• Needle EMG may overestimate clinical recovery in proximal muscles of infants with OBP.
• Clinical assessment and EMG show significant discrepancies in evaluating muscle function in this age group.
• Further research is needed to refine electrodiagnostic methods for OBP in neonates.