Three weeks after right axillary lymph node dissection, a 48-year-old woman reports difficulty pulling a heavy drawer towards her body and tucking in her shirt behind her back. Examination shows weakness of shoulder adduction, extension and internal rotation with the arm abducted. Which nerve was most likely injured?

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

Explanation

The thoracodorsal nerve arises from the posterior cord (C6, C7, C8) and accompanies the subscapular vessels along the posterior axillary wall to supply latissimus dorsi, the chief adductor, extensor and internal rotator of the abducted arm. It lies directly in the field of an axillary clearance. The long thoracic nerve is excluded because its injury causes winging of the scapula, which this patient does not have.

Reference: Moore's Clinically Oriented Anatomy, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.