Which test indicates an ACL tear with involvement of the posterior lateral corner or IT band?

• A. Slocum Test
• B. Reversed Pivot Shift Test
• C. Pivot Shift Test
• D. McMurray's Test

Answer: (C)

Pivot Shift testing targets an ACL tear by revealing anterolateral rotary instability. When the ACL is deficient, the tibia tends to sublux anteriorly, and as you move from extension into flexion with a valgus force and internal rotation, the IT band and the surrounding posterolateral structures normally tighten and pull the tibia back under the femur. This sudden reduction around 20–30 degrees of flexion produces a palpable clunk—the classic sign of a torn ACL with accompanying instability from the posterolateral corner or IT band involvement. The presence of this rotation-dependent instability is what links ACL rupture with posterolateral corner/IT band contributions, making the Pivot Shift test the best indicator of that combined injury pattern.

Other tests focus on different structures: the Reversed Pivot Shift emphasizes posterolateral instability in a different pattern; McMurray’s tests a meniscal tear; and the Slocum test isolates specific rotatory instabilities but is less specific for an ACL tear with PLC/IT band involvement.