Comprehensive Osteopathic Medical Licensing Examination (COMLEX USA) Practice

What dermatome corresponds to the medial lower leg?

1. Dermatome S2

2. Dermatome L4

3. Dermatome L5

4. Dermatome T12

The correct answer is: Dermatome L4

The correct response identifies dermatome L4 as corresponding to the medial lower leg. In the context of dermatomes, specific regions of the skin are innervated by specific spinal nerves. The L4 dermatome covers the area of the skin on the medial side of the lower leg, which is important for understanding both neuroanatomy and clinical assessment of sensory function. The relevance of the L4 dermatome is particularly significant during a physical examination or when evaluating a patient with potentially compromised nerve function, as sensory deficits in this area can indicate issues related to the lumbar spine or the L4 nerve root. Additionally, it is essential for clinicians to understand dermatomes for effective diagnosis and treatment of conditions like herniated discs or radiculopathy. Understanding the dermatomes helps to create a more comprehensive picture of the body's neural mapping and informs differential diagnoses for conditions resulting in numbness or pain in specific skin areas.