Physical Therapy Assistant Practice Exam

What functional movement would most likely be impaired in a patient with C6 spinal cord injury regarding elbow extension?

1. Inability to flex at the elbow

2. Inability to extend at the elbow

3. Inability to plantar flex the foot

4. Inability to abduct the shoulder

The correct answer is: Inability to extend at the elbow

In a patient with a C6 spinal cord injury, the function of the muscles typically innervated at this level is significantly impacted. The C6 nerve root primarily contributes to the innervation of the muscles involved in elbow flexion and extension. With a C6 spinal cord injury, the ability to extend the elbow is particularly compromised because the triceps muscle, responsible for this movement, is primarily innervated by the C7 nerve root. While a patient may retain some functionality of the biceps and forearm muscles, the extension of the elbow becomes impaired as the triceps are unable to receive appropriate signals from higher up in the spinal cord. Therefore, the correct answer reflects the specific loss of elbow extension due to the neurological impairment resulting from the injury. This highlights the significance of understanding spinal cord injury levels and their impact on muscle function, especially in a rehabilitation context for physical therapy assistants.