Klumpke's paralysis involves which nerve roots?

Klumpke's paralysis involves which nerve roots?

• A. C5-C6
• B. C8-T1
• C. C7-C8
• D. C3-C4

Answer: (B)

Klumpke's paralysis is a lower-brachial-plexus injury, involving the nerve roots that feed the hand. Specifically, it affects the C8 and T1 roots, which give rise to the nerves that control the intrinsic hand muscles through the ulnar nerve and parts of the median nerve. When these roots are damaged, intrinsic hand function is lost, leading to weakness of finger flexors and interossei and a characteristic clawing of the fingers, with impaired grip. Because the higher roots (C5-C6) that power the shoulder and elbow are spared, shoulder abduction and elbow flexion may remain relatively preserved. The mechanism is typically traction on the arm, such as in birth trauma or a fall with a sudden pull on the arm, which explains why this pattern specifically targets the hand. Occasionally Horner syndrome can accompany Klumpke’s injury due to involvement of the sympathetic chain at T1. In contrast, injuries to the upper roots (C5-C6) produce Erb-Duchenne palsy with more pronounced shoulder and upper-arm weakness and a different posture, while injuries limited to higher cervical levels would produce broader neck/respiratory concerns rather than this hand-dominant pattern. The key point is that Klumpke's palsy classically involves C8-T1.

Klumpke's paralysis is a lower-brachial-plexus injury, involving the nerve roots that feed the hand. Specifically, it affects the C8 and T1 roots, which give rise to the nerves that control the intrinsic hand muscles through the ulnar nerve and parts of the median nerve. When these roots are damaged, intrinsic hand function is lost, leading to weakness of finger flexors and interossei and a characteristic clawing of the fingers, with impaired grip.

Because the higher roots (C5-C6) that power the shoulder and elbow are spared, shoulder abduction and elbow flexion may remain relatively preserved. The mechanism is typically traction on the arm, such as in birth trauma or a fall with a sudden pull on the arm, which explains why this pattern specifically targets the hand.

Occasionally Horner syndrome can accompany Klumpke’s injury due to involvement of the sympathetic chain at T1. In contrast, injuries to the upper roots (C5-C6) produce Erb-Duchenne palsy with more pronounced shoulder and upper-arm weakness and a different posture, while injuries limited to higher cervical levels would produce broader neck/respiratory concerns rather than this hand-dominant pattern. The key point is that Klumpke's palsy classically involves C8-T1.