OT Kinesiology 3

Question 1

Which rotator cuff muscle is most commonly torn and is responsible for initiating shoulder abduction from 0–15 degrees?

Accepted Answer

Supraspinatus

Answer

The supraspinatus initiates shoulder abduction and is the most frequently torn rotator cuff muscle due to its vulnerable position under the acromion.

Question 2

A client with a radial nerve injury at the spiral groove presents with which primary deficit relevant to hand function?

Accepted Answer

Loss of wrist extension and finger extension (wrist drop)

Answer

Radial nerve injury at the spiral groove results in wrist drop due to paralysis of wrist and finger extensors, impairing functional grasp patterns.

Question 3

The scapulohumeral rhythm describes the ratio of glenohumeral to scapulothoracic movement during shoulder abduction. What is this ratio?

Accepted Answer

2:1 glenohumeral to scapulothoracic

Answer

The scapulohumeral rhythm is approximately 2:1, meaning for every 3° of shoulder abduction, 2° occur at the glenohumeral joint and 1° at the scapulothoracic articulation.

Question 4

An OT is analyzing a client's pinch strength. Which joint is primarily stabilized by the first dorsal interosseous muscle during lateral (key) pinch?

Accepted Answer

Metacarpophalangeal joint of the index finger

Answer

The first dorsal interosseous abducts the index finger and stabilizes its MCP joint, providing the radial force necessary for lateral pinch against the thumb.

Question 5

When analyzing torque in a therapeutic exercise, which variable, if doubled, would have the greatest effect on increasing torque?

Accepted Answer

The moment arm length

Answer

Torque = Force × moment arm; doubling the moment arm doubles the torque, making it the most direct way to increase rotational force in joint mechanics.

OT - Master of Occupational Therapy Practice Test

OT - Master of Occupational Therapy Practice Test

OT Kinesiology 3