Klumpke Palsy (C8–T1 Brachial Plexus Injury)
Klumpke palsy results from injury to the inferior trunk of the brachial plexus. It is classically associated with sudden, violent upward pulling of the arm, often in the abducted position.
| Functional Deficit | Key Muscles/Nerves Involved |
|---|---|
| Intrinsic hand muscles | Thenar, hypothenar, interossei, lumbricals (Ulnar and Median nerves). |
| Hand posture | “Claw hand” (hyperextension of MCP, flexion of IP joints). |
High-Yield Clinical Notes:
- Mechanism: Often caused by grabbing an object to break a fall (e.g., hanging from a branch) or during a difficult birth.
- Horner Syndrome: Because the T1 nerve root carries sympathetic fibers to the head and neck, an injury here can present with ipsilateral ptosis, miosis, and anhidrosis.
- Sensory Loss: Affects the medial aspect of the forearm and hand (C8 and T1 dermatomes).