Flexion and extension gap measurements in total knee arthroplasty after sacrifice of posterior cruciate ligament.

Twenty-three patients had 25 total knee arthroplasties. The flexion and extension gaps were measured before and after resection of the posterior cruciate ligament. The extension gap increased 2.0 +/- 0.2 mm in the medial compartment and 1.9 +/- 0.3 mm in the lateral compartment. The flexion gap increased 1.4 +/- 0.2 mm in the medial compartment and 2.3 +/- 0.3 mm in the lateral compartment. All increases were statistically significant.