The nerve shows a decrease to both tetanic and galvanic stimulation is associated with which reaction?

• A. Reaction of degeneration is not involved
• B. Accompanies partial reaction of degeneration
• C. Accompanies full reaction of degeneration
• D. Accompanies absolute reaction of degeneration

Answer: (B)

Nerve excitability under electrotherapy changes in a graded way as degeneration progresses. Galvanic stimulation directly depolarizes nerve fibers, and tetanic stimulation tests the nerve's ability to sustain firing. When a nerve shows reduced responses to both types of stimulation, it indicates that some nerve fibers are still functioning but overall excitability is diminished. This pattern corresponds to a partial reaction of degeneration, where function is impaired but not completely lost. If degeneration were more extensive, responses would be even more blunted or absent, and in a less advanced stage you might see closer to normal responses.