A new software application has been added to CINARTRO, a clinical tool to study knee kinematics from vid-eofluoroscopic images during extension. The user selects, for each image, a set of points located on the Tibial Plateau and Condyle projections to determine the value of the Tibiofemoral Contact Point and a proxy of the Quadriceps Ligament Moment Arm. The software generates reports in PDF, Excel and CDA formats. CDA (Clinical Document Architecture) reports are up-loaded into an XDS repository, as part of the patient clinical record. To solve the problem of “pincushion” effect in images, a gray tone recognition algorithm and distortion correction algo-rithm were implemented. The software was used to analyze data of injured and healthy knees of 3 patients. Precision errors in-troduced during the location of the points were 0.235mm. The Tibiofemoral Contact Point shows an average displacement of 59% in terms of tibial plateau length for healthy knees and 49% for injured knees. The average Moment Arm proxy was 50mm for healthy and 45mm for injured knees. The reduction in Quadriceps Muscle strength after ACL injury is compensated by a 11% increase in the Quadriceps Moment Arm. Keywords : Knee Kinematics, Anterior Cruciate Ligament (ACL), Tibio-Femoral Contact Point (TFCP), Quadriceps Mo-ment Arm, Computer Document Architecture (CDA).