National Board of Chiropractic Examiners (NBCE) Practice Test

Which symptom is least likely to occur from nerve compression due to a C5-C6 subluxation complex?

1. Altered triceps reflex

2. Weakness in shoulder abduction

3. Pain radiating down the arm

4. Loss of grip strength

The correct answer is: Altered triceps reflex

The symptom that is least likely to occur from nerve compression due to a C5-C6 subluxation complex is the altered triceps reflex. When considering the anatomy of the cervical spine, the C5 and C6 nerve roots primarily supply the deltoid muscle (responsible for shoulder abduction) and the biceps brachii (which helps with elbow flexion, influencing grip strength). Additionally, pain typically radiates down the arm as a result of nerve root irritation or compression in the cervical region, especially from the C5-C6 area, impacting the upper limb. Weakness in shoulder abduction would also be expected, as the deltoid is innervated by the C5 root. Loss of grip strength can be attributed to the weakness of the biceps and other muscles innervated in this region. In contrast, the triceps reflex is primarily associated with the C7 nerve root. Therefore, an alteration in the triceps reflex is less likely to directly stem from a C5-C6 subluxation, making it the least relevant symptom among the options listed in relation to C5-C6 nerve compression.