Table 2

Evaluation of posterior knee instability Clinical test findings and the corresponding stress radiograph values in evaluating posterior knee instability.

GradeClinical finding with posterior drawer testKneeling stress radiographs
I0–5 mm PTT0–7 mm PTT→normal or partial tear
II5–10 mm PTT8–11 mm PTT→Complete PCL tear
III>10 mm PTT→posterior sag≥ 12 mm PTT→Combined ligament injury
  • PCL, posterior cruciate ligament; PTT, posterior tibial translation.