Knee
Pivot shift test
Test van MacIntosh
- What you examine
- Rotatory instability of the knee after an anterior cruciate rupture.
- Procedure
- Supine, leg extended. Apply valgus and internal rotation to the lower leg and slowly flex the knee. At around 20 to 30 degrees of flexion the tibia reduces with a jerk.
- Positive when
- A palpable or visible clunk in which the lateral tibial plateau shifts back into its normal position.
- What the test is worth
- Specificity above 0.95, sensitivity low in an awake patient (around 0.25) because guarding suppresses the test. Under anaesthesia sensitivity rises sharply.
- Caution
- Unpleasant and hard to perform on a painful knee. In the acute phase the Lachman test is preferred.
- Joint
- Knee joint
- Body region
- Knee