In a 28-year-old with C5–C6 brachial plexus avulsion (global upper trunk loss), which donor nerve is used for intercostal nerve transfer to restore elbow flexion, and what is the expected recovery timeline?
- A Spinal accessory nerve; recovery in 3–4 months
- B Intercostal nerves 3–5 to musculocutaneous nerve; recovery in 12–18 months ✓
- C Contralateral C7; recovery in 12–18 months
- D Phrenic nerve; recovery in 6 months
Correct answer: B. Intercostal nerves 3–5 to musculocutaneous nerve; recovery in 12–18 months
Explanation
In C5–C6 avulsion injuries, the intercostal nerves (typically T3–T5 or T3–T6) are harvested and coapted directly to the musculocutaneous nerve or its biceps branch to restore elbow flexion. Recovery typically takes 12–18 months due to the long distance the regenerating axons must travel. The spinal accessory nerve (CN XI) is also used but preferentially to restore shoulder abduction (suprascapular nerve). Phrenic nerve transfer risks respiratory compromise and is used cautiously.
Reference: Maheshwari Essential Orthopaedics, 6th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.