During axillary lymph node dissection for breast cancer, a nerve crossing the axilla from the second intercostal space is sacrificed. Which deficit does the patient develop?
- A Winging of the scapula
- B Numbness over the medial aspect of the upper arm ✓
- C Inability to abduct the arm beyond 90 degrees
- D Weakness of shoulder external rotation
Correct answer: B. Numbness over the medial aspect of the upper arm
Explanation
The intercostobrachial nerve arises from the second intercostal nerve and crosses the axilla to supply sensation to the medial upper arm and axilla. It is often divided during axillary dissection, leaving characteristic numbness or paraesthesia in that territory. Winging of the scapula follows long thoracic nerve injury, arm abduction loss follows thoracodorsal nerve injury, and external rotation weakness follows axillary nerve injury.
Reference: Gray's Anatomy for Students, 4th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.