CINARTRO: Clinical tool to assess knee kinematics by videofluoroscopy

Abstract

A new software application has been added to CINARTRO, a clinical tool to study knee kinematics from videofluoroscopic 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 uploaded 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 algorithm were implemented. The software was used to analyze data of injured and healthy knees of 3 patients. Precision errors introduced 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.