Which nerve root is most commonly affected in cervical radiculopathy, and which adjacent levels are also frequently involved?

• A. C5 nerve root, often with C4-C5 and C5-C6 involvement.
• B. C6 nerve root, commonly with C5-C6 and C6-C7 involvement.
• C. C7 nerve root, with C6-C7 and C5-C6 levels frequently involved.
• D. C8 nerve root, commonly with C7-C8 involvement.

Answer: (C)

In cervical radiculopathy, the nerve root most often affected is the C7 root because this level is particularly prone to compression from degenerative changes and disc herniation at the C6-7 junction as the nerve exits the foramen. When multilevel cervical spondylosis is present, adjacent levels are commonly involved too, with C6-7 and C5-6 frequently showing concurrent compression or stenosis. Clinically, C7 radiculopathy classically produces sensory changes in the middle finger and weakness in triceps and finger extension, with a diminished triceps reflex, reflecting the C7 distribution. Other roots (like C5 or C6) are less likely to be the primary affected root, and C8, while possible, is less commonly the main culprit.