C5 radiculopathy typically presents with weakness in which muscle groups?

C5 radiculopathy typically presents with weakness in which muscle groups?

• A. Deltoids and biceps
• B. Triceps
• C. Tibialis anterior
• D. Abdominals

Answer: (A)

C5 radiculopathy affects the muscles served by the C5 nerve root. The C5 myotome includes shoulder abduction (deltoid) and elbow flexion (biceps). So weakness appears in the deltoids and the biceps. The other muscle groups correspond to different nerve roots: the triceps are mainly C7–C8, the tibialis anterior is L4–L5, and the abdominal muscles are T7–T12. Thus the pattern of weakness for C5 radiculopathy best matches the deltoids and biceps.

C5 radiculopathy affects the muscles served by the C5 nerve root. The C5 myotome includes shoulder abduction (deltoid) and elbow flexion (biceps). So weakness appears in the deltoids and the biceps. The other muscle groups correspond to different nerve roots: the triceps are mainly C7–C8, the tibialis anterior is L4–L5, and the abdominal muscles are T7–T12. Thus the pattern of weakness for C5 radiculopathy best matches the deltoids and biceps.