Anterior drawer test of the knee

Purpose

To test the integrity of the anterior cruciate ligament (ACL) [1]

Technique

The patient lies supine on a plinth with their hips flexed to 45 degrees, his/her knees flexed to 90 degrees and feet flat on the plinth. The examiner sits on the toes of the tested extremity to help stabilize it. The examiner grasps the proximal lower leg, just below the tibial plateau or tibiofemoral joint line, and attempts to translate the lower leg anteriorly. The test is considered positive if there is a lack of end feel or excessive anterior translation relative to the contralateral side.[2]

Anterior Draw Test video provided by Clinically Relevant

Clinical Note

This examination must be performed with particular care because the start position could result in a false-positive anterior drawer test result for the anterior cruciate ligament if a posterior sag (an indication of a posterior cruciate problem) goes unnoticed before the test is started. If minimal or no swelling is present, the sag is evident because of an obvious concavity distal to the patella.

When the anterior drawer test is done, if an audible snap or palpable jerk (Finochietto jumping sign) occurs when the tibia is pulled forward, and the tibia moves forward excessively, a meniscal lesion is likely in addition to the torn anterior cruciate ligament. ref>Strobel M, Stedtfeld HW. Diagnostic evaluation of the knee. Springer Science & Business Media; 2012 Dec 6.</ref>

Evidence

One source reports sensitivity and specificity as .41-.91 and .86-1.0 respectively, with a -LR of .09-.62 and a +LR of 5.4-8.2.[2]  However, a recent meta-analysis reports the sensitivity and specificity as .18-.92 and .78-.98 respectively.[4]  Scholten et al concluded that based on predictive value statistics, strong conclusions could not be made regarding whether the anterior drawer test was good to rule in or rule out the presence of an ACL tear.[4]  Other recent research has identified the anterior drawer test as a more effective test to identify chronic conditions, with a sensitivity and specificity of .92 and .91.[5]

The laxity of the ACL or the instability of the knee depends on the forces applied to the knee and increases with higher force. These are different in clinical investigation and during moderate or strenuous activity. Therefore, the Anterior drawer test can't always predict the loss of the ACL or the joint instability that exists during strenuous activity. Joint laxity can be reduced when, after injury, a person reduces his or her level of activity. Thus the functional stability can be maintained. [6]

Katz and Fingeroth [1] reported that the knee anterior draw test has a diagnostic accuracy of acute ACL ruptures (within 2 weeks of examination) of: 22.2% sensitivity and >95% specificity.The study reported the diagnostic accuracy of subacute/chronic ACL ruptures (more than 2 weeks before examination) is: 40.9% sensitivity and 98.4% specificity.It is important to note that in this study all examinations were performed under anesthesia; thus the diagnostic accuracy in physiotherapy clinical practice may be less.The knee anterior draw test, although widely used, is a poor diagnostic indicator of ACL ruptures, especially in the acute setting.

Tests that are more likely to give an accurate result are the pivot shift or the Lachman. [1] [7]

References

  1. 1.0 1.1 1.2 Katz JW, Fingeroth RJ. The diagnostic accuracy of ruptures of the anterior cruciate ligament comparing the Lachman test, the anterior drawer sign, and the pivot shift test in acute and chronic knee injuries. The American Journal of Sports Medicine 1986;14:88-91.fckLRhttp://ajs.sagepub.com/content/14/1/88.short (accessed 18 July 2013).
  2. 2.0 2.1 Flynn TW, Cleland JA, Whitman JM. Users' guide to the musculoskeletal examination: fundamentals for the evidence-based clinician. United States: Evidence in Motion; 2008.
  3. Katie Yost. Physical Exam of the Knee . Available from: http://www.youtube.com/watch?v=8CZ-219Dtlc [last accessed 26/09/14]
  4. 4.0 4.1 Scholten PJPM, Opstelten W, van der Plas CG, Bijl D, Deville WLJM and Bouter LM. Accuracy of physical diagnostic tests for assessing ruptures of the anterior cruciate ligament: a meta-analysis. J Fam Pract. 2003;52:689-694.
  5. Benjaminse A, Gokeler A van der Schans CP. Clinical diagnosis of an anterior cruciate ligament rupture: a meta-analysis. J Orthop Sports Phys Ther. 2006;36(5):267-88.
  6. BUTLER DL, NOYES DR, GROOD ES, Ligamentous restraints to anterior-posterior drawer in the human knee. a biomechanical study, J Bone Joint Srug Am. 1980;62:259-270
  7. OSTROWSKI JA, Accuracy of 3 diagnostic tests for anterior cruciate ligament tears, Journal of Athletic Training, 2006, 41(1): 120-122