College of Massage Therapists of British Columbia (CMTBC) Practice Exam

During an elbow assessment, which structure is being tested by applying an adduction force to a slightly flexed elbow?

1. Ulnar collateral ligament

2. Lateral collateral ligament

3. Annular ligament

4. Medial collateral ligament

The correct answer is: Lateral collateral ligament

When applying an adduction force to a slightly flexed elbow during an assessment, the structure primarily being tested is the lateral collateral ligament. This ligament is crucial for maintaining stability on the outer part of the elbow, especially when lateral forces are applied. The lateral collateral ligament serves to resist varus stress, which is a force that pulls the forearm towards the body. When an adduction force is applied, it creates an internal rotation moment that stresses the lateral side of the elbow joint. Therefore, the assessment specifically targets the integrity of the lateral collateral ligament to evaluate its ability to withstand this particular force. In contrast, other ligaments such as the ulnar collateral ligament, annular ligament, and medial collateral ligament are not primarily engaged with adduction forces. The ulnar collateral ligament stabilizes the medial aspect of the elbow, while the annular ligament supports the radial head, allowing for rotation of the radius during forearm movement. The medial collateral ligament, similar to the ulnar collateral ligament, provides resistance to valgus stress, which is the opposite of what occurs with an adduction force.