All of the following apply to reaction of degeneration EXCEPT

• A. The lesion is in the lower motor neuron
• B. The stage of reaction denotes severity of the lesion
• C. The stage of reaction denotes the etiology of the lesion
• D. It indicates an organic lesion

Answer: (C)

Reaction of degeneration is the neuron’s response to axonal injury, typically seen in lower motor neuron lesions, where the motor neuron cell body shows changes like chromatolysis as part of a regenerative attempt. The amount and stage of this reaction reflect how long and how severe the injury is, rather than what caused it. So the presence of a reaction of degeneration points to an organic lesion affecting a motor neuron, and its stage tells you about severity and duration. It does not reveal the etiology of the lesion. That’s why stating that the stage of reaction denotes the etiology is not correct.