In neurapraxia, which of the following occurs?

• A. Wallerian degeneration occurs
• B. Axon continuity is disrupted
• C. Endoneurial disruption is extensive
• D. Nerve conduction is blocked with intact axon

Answer: (D)

In neurapraxia the nerve is functionally blocked but structurally intact. The problem is a transient demyelination around the axon, which disrupts the ability for the nerve to conduct impulses across the lesion, even though the axon itself remains continuous. Because the axon is not severed, there is no Wallerian degeneration of the distal segment and the endoneurium stays largely intact. This is why nerve conduction can be blocked at the site of demyelination but the axon remains ready to carry signals once remyelination occurs, leading to recovery typically without needing axonal regeneration. In contrast, injuries that involve axon disruption or more extensive endoneurial damage produce Wallerian degeneration and longer or incomplete recovery.