The Roles of MRI, DYNEELAX and Stress X-ray in First-Line Diagnosis of Cruciate Ligament Injury

Background: Cruciate ligament tears are clinically diagnosed by detection of anterior or posterior tibial translation on physical examination; however, this manual method of assessment is imprecise, subjective, and not reproducible. Recently a new instrument, a stress radiographic device and knee stability test (DYNEELAX), were produced to objectively measure these displacements. Objective: To assess new diagnostic methods, in the measurement of anterior/posterior tibial translation in cruciate ligament-deficient knee compared to the healthy knee. Material and method: The MRI, stress radiographic device and knee stability test was applied to cruciate ligament-tear knees that were diagnosed by physical examination as having partial or complete cruciate ligament tears. Each knee was tested under a force 120 Newtons in a posterior to anterior direction to create anterior tibial translation at 20 degrees knee flexion. Side-to-side difference of anterior/posterior tibial translation (mm) was measured from radiographs. Measurement of rotation and translation by DYNEELAX was also recorded.