Duck Walk Test (or Childress Sign) is a weightbearing test that is used to evaluate the posterior horn of the meniscus.
It was first described by by Harold M. Childress In 1957.
See Also: Knee Meniscus Injury
The patient assumes a squatting position, preferably with the buttocks in contact with the heels. The patient is then asked to waddle in this position (duck waddling).
In the presence of an injury to the posterior horn, the patient will notice a painful snapping shortly before maximum flexion or in the early phase of extension.
This is caused by impingement of the injured meniscus.
Patients in severe pain will usually be unable to assume the squatting position.
See Also: Knee Meniscus Anatomy
In a study to evaluate the diagnostic accuracy of the Duck Walk Test in detecting meniscal tear, the calculated sensitivity and specificity was as following:
Cabot Test is another knee special test that is used to evaluate the posterior horn of the lateral meniscus.
The patient is place in the supine position. With the affected leg flexed at the knee and placed over the proximal portion of the contralateral lower leg. With one hand, the examiner grasps the patient’s knee and palpates the lateral joint cavity with the thumb. With the other hand, the examiner grasps the patient’s lower leg slightly proximal to the subtalar joint. The patient is then asked to extend the knee against the resistance of the examiner’s hand.
Pain will occur where there is a lesion of the posterior horn of the lateral meniscus (a positive Cabot test). Depending on the severity of the pain, the patient will often be unable to extend the knee farther.
The painful point, which is palpable with the thumb, lies primarily in the lateral posterior joint cavity.
Occasionally patients will report pain radiating into the popliteal fossa and calf.
This test is also described in the literature as the popliteus sign.