After a right axillary lymph node clearance for breast carcinoma, a woman complains of difficulty pulling herself up and reaching overhead objects. Examination shows weakness of shoulder extension, adduction and internal rotation with normal scapular position. Which nerve was most likely injured?

• A Thoracodorsal nerve ✓
• B Long thoracic nerve
• C Upper subscapular nerve
• D Medial pectoral nerve

Explanation

The thoracodorsal nerve (C6 to C8) runs on the posterior wall of the axilla with the subscapular vessels and supplies latissimus dorsi, whose actions are shoulder extension, adduction and internal rotation. It is at risk during axillary node dissection because it lies close to the nodes. Scapular position is normal here because serratus anterior is intact, which excludes the long thoracic nerve and makes option B the distractor to reject.

Reference: Gray's Anatomy for Students, 4th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.