Dr. Kevin Yip

Dr Kevin Yip
Orthopaedic Surgeon
MBBS(UK), FRCS(EDIN), FAM(SING), FHKCOS(ORTHO)

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Varus strain

Positioning.

The subject lies in the supine position with the knees extended. The examiner
stands level with the subject’s knee. The ipsilateral hand grasps the lower leg from the lateral side, just proximal to the lateral malleolus. The other hand is pronated and placed at the medial femoral condyle.

Procedure.

Lift the extended leg and apply strong varus pressure with the distal hand. Counterpressure is maintained at the medial femoral condyle.

Common mistakes.

The knee is not fully extended during the procedure.

Normal functional anatomy:

• Rallge: in a normal knee no perceptible movement is possible
• Elld-feel: hard ligamentous
• Limiting structures:

– lateral collateral ligament
– arcuate ligament
– posterior cruciate ligament.

Variation of the varus test

The test can be repeated with the knee in slight flexion (20-30°). Here the thigh rests on the couch and the lower leg hangs over the edge. The examiner
stands distal to the foot. Again, the lower hand provokes a varus strain while the hand at the knee stabilizes.In this position the cruciate ligaments no longer
hold both joint surfaces in firm apposition; therefore some movement is possible and more stress is put on the lateral ligamentous complex.

Common pathological situations:

• Lateral pain during varus stress inculpates the lateral collateral ligament; medial pain may accompany an impacted loose body or impacted medial meniscus.
• Increased range in 30° of flexion is typical for a rupture of the lateral collateral ligament.
• If varus stress in full extension also shows an increased range, the posterior cruciate ligament is probably torn as well.

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