National Registry of Certified Medical Examiners (NRCME) DOT Practice Exam

Which assessment is indicative of L4 nerve root pathology?

1. Plantar flexion

2. Patellar reflex

3. Hip Extension

4. Hand in pocket paresthesia

The correct answer is: Patellar reflex

The patellar reflex is indicative of L4 nerve root pathology due to its specific neurological pathway. The L4 nerve root is primarily responsible for innervating the quadriceps muscle, which is involved in the knee extension process. When the knee is tapped at the patellar tendon, a proper response will indicate good function of the L4 root, as it reflects the monosynaptic reflex arc that involves sensory inputs from the patellar tendon and motor outputs to the quadriceps muscle. The significance of this assessment lies in its ability to identify potential issues along the L4 nerve root specifically, such as compression or injury, which would manifest as a diminished or absent reflex response. This is relevant in clinical evaluations where the integrity of the lumbar nerve roots is assessed as part of diagnosing lower extremity neurological conditions. In contrast, the other options represent different muscle groups and reflexes that are associated with other nerve roots or do not directly correlate with L4 pathology. Plantar flexion primarily involves the S1 nerve root, hip extension is associated with the L5 and S1 roots, and paresthesia in the hand would typically reflect issues with cervical nerve roots, therefore, they do not specifically indicate L4 nerve root pathology as clearly as the patellar