Physical Therapy Assistant Practice Exam

If a patient post-anterior cruciate ligament repair lacks 20 degrees of knee extension, which range of motion measurement could be consistent with this finding?

1. 10-90 degrees

2. 20-95 degrees

3. 15-100 degrees

4. 0-95 degrees

The correct answer is: 20-95 degrees

The answer of 20-95 degrees of knee flexion correlates well with a patient who is lacking 20 degrees of knee extension after an anterior cruciate ligament repair. In this context, full knee extension is typically measured as 0 degrees. Therefore, if the patient is unable to fully extend the knee to 0 degrees, they would be demonstrating a lack of extension. With a range of motion of 20-95 degrees, the 20 degrees represents the level of flexion where the knee does not reach full extension. This range indicates that the patient can flex the knee to a maximum of 95 degrees but begins at 20 degrees, reflecting the deficit in extension. Thus, it is consistent with the finding of lacking 20 degrees of knee extension. Other ranges do not align with this deficit as clearly. For instance, the range of 0-95 degrees would imply that the patient can fully extend the knee to 0 degrees, which contradicts the statement about the lack of extension. This precise alignment with the 20-degree lack of extension makes 20-95 degrees the most fitting choice.