A 48-year-old woman undergoes modified radical mastectomy with axillary clearance for breast cancer. On postoperative day 2, she complains of numbness over the medial aspect of the right arm. Which nerve is most likely injured?
- A Long thoracic nerve
- B Intercostobrachial nerve ✓
- C Thoracodorsal nerve
- D Medial pectoral nerve
Correct answer: B. Intercostobrachial nerve
Explanation
The intercostobrachial nerve (lateral cutaneous branch of T2) is routinely sacrificed during axillary dissection and supplies sensation to the medial arm and axillary skin. Its injury causes numbness over the medial arm, a common and expected finding post-mastectomy. Long thoracic nerve injury causes scapular winging. Thoracodorsal nerve injury affects latissimus dorsi. Medial pectoral nerve injury affects pectoral muscles.
Reference: Bailey and Love's Short Practice of Surgery, 28th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.