Gross Anatomy USMLE Step 1 Practice Question
A 34-year-old male is examined in the prison infirmary after sustaining a superficial stab wound to the superolateral aspect of the thoracic wall at the level of the third rib. There is little bleeding and no difficulty breathing; however, the medial border of the scapula on the injured side pulls away from the body wall when the arm is raised. In addition, the arm cannot be abducted above the horizontal. Which of the following muscles is paralyzed?
Answer choices
- ARhomboid major
- BPectoralis minor
- CLevator scapulae
- DSerratus anteriorCorrect answer
- ESupraspinatus
- FTrapezius
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