The axial view in evaluating tibial translation in cases of insufficiency of the posterior cruciate ligament

The purpose of this report is to present a new radiological method of diagn osis and evaluation of posterior instability using the patellofemoral axial view. During a period of 22 months, we performed clinical and radiological assessments on 20 patients (6 acute and 14 chronic) with isolated posterio r instability caused by posterior cruciate ligament (PCL) rupture and on 20 patients with normal knees. The radiological examination included stress r adiographs using the Telos device (Telos, Griesheim, Germany) as well as a modification of the routine axial patellofemoral view. Both diagnosis and q uantification of the posterior tibial translation was possible in all cases by measuring, on the axial view, the distance between the anterior edge of the tibial plateau and the center of the femoral groove (trochlea). Clinic al examination, conventional radiography, KT-1000 arthrometry, stress radio graphy at 90 degrees and at 20 degrees of flexion, and magnetic resonance i maging all assist in diagnosing a PCL tear. This new radiographic technique is simple, fast, and consistently effective both in patients with acute an d those with chronic PCL tears, as well as in those who have undergone PCL reconstruction.