Question

During an attempted robbery, a 20-year-old man of average body build is stabbed once with a long, narrow knife. Initial examination in the emergency room indicates the knife penetrated the anterior wall of the right axilla and reached approximately the center of the axillary space. Which of the following is most likely true of this injury?
a. The knife penetrated the teres major muscle.
b. The knife pierced the pectoralis minor muscle to reach the cords of the brachial plexus.
c. The knife probably struck one of the trunks of the brachial plexus.
d. The suprascapular nerve is probably lesioned.
e. The man will likely develop a "winged scapula" condition.

Answer 1

Answer:

b. The knife pierced the pectoralis minor muscle to reach the cords of the brachial plexus

Explanation:

According to the question, the knife penetrated the anterior wall of the right axilla and reached to the centre of the axillary space. The pectoralis minor muscles are located at this place. Pectoralis minor muscles are small muscles that are located in the region of left and right chest, just under the pectoralis larger muscles. At the same place a network of nerve fibers is found which sends signal from spinal cord to the shoulder, arm and hand. This is the brachial plexus.