Musculoskeletal growth in the upper arm in infants after obstetric brachial plexus lesions and its relation with residual muscle function.

Aim: Denervation after obstetric brachial plexus lesion (OBPL) is associated with reduced musculoskeletal growth in the upper arm. The aim of this study was to investigate whether reduced growth of upper arm flexor and extensor muscles is related to active elbow function and humeral length.

Method: In this study, 31 infants age less than 6 months (mean age 4.