Which description best fits peripheral neuropathy?

• A. Radiculopathy produces dermatomal pattern of weakness with reflex changes
• B. Diffuse non-dermatomal sensory loss
• C. Myotomal weakness with reflex changes
• D. Nerve-specific deficits with sensory/motor involvement in a single peripheral nerve distribution

Answer: (D)

Focus on how a lesion localizes: peripheral neuropathy means disease of the peripheral nerves themselves. When a single nerve is involved, you get deficits confined to that nerve’s territory, affecting both sensation and motor function in the areas that nerve supplies, often with reflex changes limited to those muscles. This nerve-specific pattern matches a peripheral nerve lesion rather than a nerve root problem. In contrast, radiculopathy follows a dermatomal distribution because it involves a nerve root, and myotomal weakness follows a myotome with corresponding reflex changes. A diffuse, non-dermatomal sensory loss doesn’t fit a single peripheral nerve distribution and points away from a focal peripheral neuropathy. So the description of deficits localized to a single peripheral nerve’s sensory and motor territory best fits peripheral neuropathy.