Which description corresponds to the absolute reaction of degeneration in nerve or muscle testing?

• A. Partial reaction of degeneration
• B. Full reaction of degeneration
• C. No reaction to degeneration is involved
• D. Absolute reaction of degeneration

Answer: (D)

In nerve and muscle testing, the way degeneration presents itself describes how much innervation remains after injury. The absolute reaction of degeneration means complete loss of innervation to the muscle—there is no residual motor unit activity or response to electrical stimulation. In other words, the muscle cannot be activated at all by neural input, and there’s no remaining conduction along the nerve to produce a contraction. This indicates a severe, essentially irreversible denervation state.

Partial reaction would imply some residual innervation and a diminished but detectable response, while no reaction to degeneration involved isn’t a standard way to describe the level of denervation. The absolute reaction is the term used when degeneration is complete and no functional response can be elicited.