OT Anatomy & Physiology 2 — Questions and Answers
Question 1: Which rotator cuff muscle is most commonly torn in overhead occupational tasks?
- Infraspinatus
- Supraspinatus (Correct answer)
- Subscapularis
- Teres minor
Correct answer: Supraspinatus
The supraspinatus tendon passes under the acromion and is most vulnerable to impingement and tearing during overhead activities.
Question 2: The brachial plexus originates from which spinal cord levels?
- C3–C7
- C5–T1 (Correct answer)
- C4–C8
- C6–T2
Correct answer: C5–T1
The brachial plexus is formed from the ventral rami of spinal nerves C5 through T1, innervating the upper extremity.
Question 3: Which carpal bone is most frequently fractured in a fall on an outstretched hand (FOOSH)?
- Lunate
- Trapezium
- Scaphoid (Correct answer)
- Hamate
Correct answer: Scaphoid
The scaphoid is fractured in about 70% of carpal fractures due to its position bridging the proximal and distal carpal rows during FOOSH impact.
Question 4: Which nerve is compressed in pronator teres syndrome, producing forearm pain and median nerve symptoms?
- Ulnar nerve
- Radial nerve
- Anterior interosseous nerve
- Median nerve (Correct answer)
Correct answer: Median nerve
Pronator teres syndrome involves compression of the median nerve between the two heads of the pronator teres muscle in the proximal forearm.
Question 5: The interossei muscles of the hand are primarily innervated by which nerve?
- Median nerve
- Radial nerve
- Ulnar nerve (Correct answer)
- Musculocutaneous nerve
Correct answer: Ulnar nerve
Both the palmar and dorsal interossei are innervated by the deep branch of the ulnar nerve (C8–T1).
Question 6: During elbow flexion, which muscle is the primary mover when the forearm is in neutral (mid-pronation/supination) position?
- Biceps brachii
- Brachioradialis
- Brachialis (Correct answer)
- Coracobrachialis
Correct answer: Brachialis
The brachialis is the most consistent elbow flexor regardless of forearm position, as it inserts on the ulnar tuberosity rather than the radius.
Question 7: Which structure forms the floor of the carpal tunnel?
- Flexor retinaculum
- Palmar aponeurosis
- Carpal bones (Correct answer)
- Pronator quadratus
Correct answer: Carpal bones
The carpal bones form the floor and sides of the carpal tunnel, while the flexor retinaculum forms the roof.
Which rotator cuff muscle is most commonly torn in overhead occupational tasks?