Comprehensive Osteopathic Medical Licensing Examination (COMLEX USA) Practice

What is the spinal level range for the lower extremities?

1. T10-L2

2. T10-L1

3. T12

4. L1-L2

The correct answer is: T10-L2

The spinal level range for the lower extremities is primarily found in the lumbar and sacral regions of the spinal cord. The correct choice reflects the range of spinal segments that give rise to the nerves innervating the lower limbs. The lower extremities are innervated by spinal nerves originating from the lumbar and sacral plexuses, specifically from T10 through the lumbar region down to L2. This arrangement includes not only the lumbar segments but also the thoracic segment that contributes to the sympathetic innervation in the lumbar region. The combination of T10 to L2 indicates the contributions from the lower thoracic and lumbar spinal nerves, which play a critical role in the motor and sensory innervation of the legs. In contrast, the other options are too limited in the spinal range to adequately cover the neural supply to the lower extremities. Spinal levels restricted to T10-L1, T12, or strictly L1-L2 fail to incorporate the full range of innervation necessary for complete lower limb function. Thus, the spinal level range for the lower extremities is appropriately represented by T10-L2.