Tests to Detect a Meniscus Tear
- Joint Line Tenderness
Joint line tenderness is a very non-specific test for a meniscus tear. The area of the meniscus is felt, and a positive test is considered when there is pain over the area where the meniscus is found. - McMurray's Test
McMurray's test is performed with the patient lying flat (non-weight bearing) and the examiner bending the knee. A click is felt over the meniscus tear as the knee is brought from full flexion to 90 degrees of flexion. - Ege's Test
Ege's test is a specific maneuver to detect a meniscus tear. With a patient squatting, an audible and palpable click is heard/felt over the area of the meniscus tear. The patient's feet are turned outwards to detect a medial meniscus tear, and turned inwards to detect a lateral meniscus tear.
Tests to Detect Ligament Injury
- Lachman Test
The Lachman test is the best test to diagnose an ACL tear. With the patient lying flat and relaxed, the examiner bend the knee slightly, about 20 degrees. The examiner then stabilizes the thigh while pulling the shin forward. Both the amount of translation (shifting) as well as the feel of the endpoint offer information about the ACL. - Anterior Drawer Test
The anterior drawer test is also performed with the patient lying flat. The knee is bent 90 degrees and the shin is pulled forward to check the stability of the ACL. An intact ACL will only allow the shin to come forward slightly. A torn ACL will allow the shin to move further forward. - Pivot Shift Test
The pivot shift test is a difficult maneuver to perform on a patient who is not under anesthesia. This test places a stress on the knee joint that forces a subluxation (partial dislocation) in patients who do not have an ACL. This test recreates the type of instability that caused the ACL injury. - Posterior Drawer Test
The posterior drawer is performed similarly to the anterior drawer test. This test detects injury to the PCL. By pushing the shin backward, the integrity of the PCL is tested. Excessive movement of the shin backwards is a sign of PCL injury. - Varus and Valgus Instability
Varus and valgus instability tests check the LCL and MCL, respectively. With the patient lying flat, and the knee held at about 30 degrees of flexion, the shin is shifted to each side. Insufficiency of the LCL or MCL will allow the knee to "open up" excessively. The test is repeated with the leg straight. If the knee still opens up excessively, then more than just the LCL or MCL was torn. - Dial Test
The dial test checks the rotation allowed at the knee joint. Patients who have posterolateral rotatory instability, may have excessive rotation at the knee joint. The test is done with the patient lying face down, and the knees bent about 30 degrees. The feet are turned outwards and compared to each other. Excessive rotation is a sign of posterolateral corner injury.
Tests to Detect Kneecap Problems
- Patellar Grind Test
Patellar grinding is a nonspecific test where the examiner feels for abnormal grinding sensations under the kneecap with movement of the joint. If pressure on the kneecap recreates the symptoms this may indicate the kneecap is the culprit. - Patellar Facet Tenderness
The examiner can slightly lift up the kneecap and place direct pressure on the undersurface of the kneecap. By doing so, the examiner is looking for sensitive regions of cartilage underneath the kneecap. - Patellar Apprehension Test
Patellar apprehension is a sign of an unstable kneecap. While the examiner places pressure on the kneecap, the patient may complain of the sensation that the kneecap is going to 'pop out' of its groove. This is a sign of kneecap instability.
References:
- O'Shea, KJ et al. "The diagnostic accuracy of history, physical examination, and radiographs in the evaluation of traumatic knee disorders" Am. J. Sports Med., Mar 1996; 24: 164 - 167.
