Posterior Drawer Test

In this maneuver, the patient is supine with the feet on the table, the hip flexed 45 degrees and the knee flexed 80 to 90 degrees. Because the posterior drawer test is based on the relationship between the medial femoral condyle and the medial tibial plateau, comparison to the contralateral side is important in interpretation. First, the examiner must evaluate the tibial starting point. Normally, the tibial plateau step-off is approximately 1cm anterior to the femoral condyle (Fig. 53-6). If a normal step-off is not palpated, PCL injury should be suspected. Next, a posteriorly directed force is applied to the anterior tibia. In a grade I injury, a palpable but diminished step-off is present, in which the tibial plateau remains anterior to the medial condyle (0- to 5-mm tibial displacement). In grade II injury, the plateau is palpated flush (5- to 10-mm displacement) but cannot be displaced behind the medial femoral condyle, and grade III refers

Figure 53-6 Tibial step-off is assessed during the posterior drawer test. The examiner's finger is used to palpate the relationship of the medial tibial plateau to the medial femoral condyle. (From Allen CR, Rihn JA, Harner CD: Posterior cruciate ligament: Diagnosis and decision making. In Miller MD, Cole BJ [eds]: Textbook of Arthroscopy. Philadelphia, WB Saunders, 2004, pp 687-702.)

Figure 53-6 Tibial step-off is assessed during the posterior drawer test. The examiner's finger is used to palpate the relationship of the medial tibial plateau to the medial femoral condyle. (From Allen CR, Rihn JA, Harner CD: Posterior cruciate ligament: Diagnosis and decision making. In Miller MD, Cole BJ [eds]: Textbook of Arthroscopy. Philadelphia, WB Saunders, 2004, pp 687-702.)

to cases in which the plateau can be displaced posterior to the condyle (10- to 15-mm displacement)15 (Fig. 53-7). One should also assess the endpoint when performing the posterior drawer test. Most acute injuries have an altered endpoint, although this may return to normal in chronic injuries in as quickly as a few weeks.4

If the tibia displaces more than 10 mm (grade III laxity), a combined injury, most commonly involving the PLCC, should be suspected. Careful examination of the ACL, collateral ligaments, and PLCC is crucial. PCL injury typically allows maximal posterior translation at 90 degrees of knee flexion, which is why the posterior drawer test is performed in this position. Maximal translation at 30 degrees, which decreases at 90 degrees, may indicate isolated PLCC injury.13 It is also critical to recognize that PCL incompetence may cause the tibia to rest in a posteriorly subluxed position, causing a false-positive Lachman test. In fact, it has been reported that 15% of patients surgically treated for isolated PCL injuries have previously undergone unnecessary ACL reconstruction as result of misdiagnosis (Box 53-2).5

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Cure Tennis Elbow Without Surgery

Cure Tennis Elbow Without Surgery

Everything you wanted to know about. How To Cure Tennis Elbow. Are you an athlete who suffers from tennis elbow? Contrary to popular opinion, most people who suffer from tennis elbow do not even play tennis. They get this condition, which is a torn tendon in the elbow, from the strain of using the same motions with the arm, repeatedly. If you have tennis elbow, you understand how the pain can disrupt your day.

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