A 48-year-old man complains of muscle weakness in his right hand (dominant hand). On examination, the hand muscles are smaller than on the left, and the reflexes are decreased out of proportion to weakness.For the above patient with muscle weakness, select the most likely anatomic site for the disorder.
High-Yield Explanation
Peripheral nerve lesions result in reflex loss greater than the degree of weakness. Reflex loss is variable in anterior horn cell disease and decreased proportionately in muscle disease. In neuromuscular junction disorders, reflexes are characteristically normal.