Neonatal Nurse Practitioner Practice Exam

Which reflex is absent in total brachial plexus palsy that distinguishes it from Erb's palsy?

1. Grasp

2. Moro

3. Radial

4. Rooting

The correct answer is: Grasp

In the context of total brachial plexus palsy, the absence of the grasp reflex serves as a distinguishing feature from Erb's palsy. Total brachial plexus palsy involves a complete disruption of the brachial plexus, resulting in a total loss of innervation to the affected arm. This leads to the inability to perform basic reflexes, such as grasping, as the necessary neural pathways are compromised. In contrast, Erb's palsy, which typically affects only the upper trunk of the brachial plexus (C5-C6), can still preserve some reflex responses because the lower parts of the plexus may remain intact. Therefore, while the grasp reflex is absent in cases of total brachial plexus palsy, it may still be present in Erb's palsy, creating a clear clinical distinction. This differentiation is crucial for diagnosis and management, as it helps guide treatment and intervention strategies. Understanding the functional implications of these types of palsy allows healthcare providers to create more tailored rehabilitation plans based on the specific injuries to the brachial plexus.