Neonatal brachial plexus palsy (NBBP) is a stretch injury to the brachial plexus (BP) during the
birth process, resulting in varying degree of paralysis. No data exists on the biomechanical and
functional responses and associated structural damage of the complex BP when subjected to
stretch. Detailed knowledge of these properties are required to fully characterize the mechanism
of injury that will allow clinicians to develop strategies that minimize the occurrence of NBPP
and also guide treatment strategies. The aims of this study are to determine the biomechanical
and physiological injury thresholds and the resulting structural changes during stretch injuries to
the neonatal BP. The study further expands to develop a more human-like computational model,
which can be used to advance the science of obstetrical care through training and education. All
proposed aims of this study would engage several undergraduates thereby enhancing the
research program at Widener University.
Proposed Specific Aim 1 will provide a detailed understanding of the biomechanical properties
of the neonatal BP complex through in vivo tensile testing of the neonatal BP in an
experimentally powerful piglet animal model. Specific Aim 2 will identify the functional injury
thresholds of the neonatal BP. By subjecting various segments of the BP to known strains, we
will determine the threshold for both spontaneous recovery as well as permanent functional
damage in the BP complex after stretch injuries. No such data is available in the literature,
which limits the prognosis of the injury and treatment selection. Specific Aim 3 will identify the
histological changes in the BP post stretch injury, including changes in the nerve fibers, such as
increased spacing or torn fibers, myelin changes, extent of blood vessel rupture, and impaired
axoplasmic transport. Histological findings will greatly enhance the understanding of the injury
mechanism. Specific Aim 4 will use the data from Aims 1 & 2 to improve the human like
behavior of an existing computational model that will then be used to identify the range of injury
severities that occurs to the BP during current delivery maneuvers. This model can also be
used to investigate new clinically translational obstetrical maneuvers that can minimize BP
stretch.
In summary, this study will be the first to provide the required scientific knowledge to better
understand the mechanism of NBPP, identify optimal treatment options and further advance
obstetrical care by providing a model that will not only help train the care providers to minimize
the occurrence of NBPP but also develop new delivery maneuvers that can prevent NBPP.
