The McMurray test is a specific physical examination technique used to assess for meniscal tears in the knee. It is a classic manipulative test that is performed by a healthcare professional.
How the McMurray Test is Performed
The test involves specific movements and manipulations of the knee joint to identify potential tears in the meniscus. Here's a breakdown of the procedure:
- Patient Positioning: The patient lies on their back (supine) with their knee fully bent (flexed).
- Tibial Rotation and Valgus Stress:
- For the lateral meniscus, the tibia (shin bone) is internally rotated (the foot is turned inwards). Then, a valgus stress (force applied to the outside of the knee) is applied while the knee is being extended.
- For the medial meniscus, the tibia is externally rotated (the foot is turned outwards). A valgus stress is applied, and the knee is extended.
What a Positive McMurray Test Indicates
A positive McMurray test is characterized by:
- A palpable or audible click: This clicking sensation within the knee joint might indicate a tear in the meniscus.
- Pain: The patient may experience pain along the joint line during the test.
- Popping or Locking: A feeling of popping, catching, or locking of the knee joint can suggest the presence of a torn meniscus.
It's important to note:
- A positive test suggests a meniscus tear but does not confirm it. Further diagnostic tests, such as an MRI, may be required to confirm the diagnosis.
- The test can be difficult to interpret due to variations in how the movement is performed and different patient tolerances.
Why is the McMurray Test Important?
The McMurray test, while not always completely accurate, plays a crucial role in the initial clinical assessment of potential meniscal injuries. This test helps clinicians determine whether a patient may require further diagnostic imaging.
