Question

During a fight a man is stabbed in the lateral chest beneath the right arm. The wound does not enter the chest cavity. Physical examination reveals that the vertebral (medial) border of the patient's scapula projects posteriorly and is closer to the midline on the injured side. On return visit the patient complains that he cannot reach as far forward (such as to reach for a door knob) as he could before the injury. The nerve injured which caused these symptoms is the:

A. axillary
B. long thoracic
C. musculocutaneous
D. radial
E. suprascapular

Answer 1

The symptoms described indicate an injury to the long thoracic nerve, leading to a winged scapula and the inability to protract the arm adequately.

Step-by-step explanation:

The nerve injured which caused these symptoms in a man who was stabbed in the lateral chest beneath the right arm and is now unable to reach forward as far as before is the long thoracic nerve. This nerve innervates the serratus anterior muscle, which is responsible for holding the scapula against the thoracic wall and allows for the forward reach (protraction) of the arm. The injury described leads to a condition known as 'winged scapula,' where the vertebral (medial) border of the patient's scapula projects posteriorly and is closer to the midline on the injured side due to paralysis of the serratus anterior muscle.