American Board of Internal Medicine (ABIM) Certification Practice Exam

What is a common reporting symptom of patients with meniscal injuries?

1. Severe stabbing pain

2. Persistent dull ache

3. Locking of the knee

4. Limited range of motion

The correct answer is: Locking of the knee

In the context of meniscal injuries, the symptom of knee locking is particularly characteristic and frequently reported by patients. This phenomenon occurs due to a piece of the torn meniscus becoming trapped in the knee joint, preventing full movement. When this impingement occurs, it can create an acute episode where the knee cannot fully extend or flex, resulting in a sensation of the knee being "locked." While severe stabbing pain, a persistent dull ache, and limited range of motion can also occur with meniscal injuries or other knee pathologies, they are not as specific to this type of injury as knee locking. Severe stabbing pain may suggest acute injury or significant internal damage, while a persistent dull ache often points to chronic conditions. Limited range of motion can arise from various knee issues, including inflammation or injury to surrounding structures, but does not directly imply the mechanical dysfunction typically associated with meniscal tears. Thus, the sensation of locking is a distinct and well-defined symptom that aligns closely with the underlying mechanics of meniscal injury, making it a key indicator during patient assessments.