Knee diagram for the documentation of arthroscopic findings of the knee — cadaveric study

Abstract

There is a need for an accurate representation of arthroscopic knee findings on a diagram. The first time in the literature this Knee Diagram is generated, using three-dimensional projection of the four dissected cadaveric knees articular surfaces. Computer-aided design and drafting software is utilized to find the average dimensions of the four cadaveric knee surfaces. Mercator earth projection principle is applied in drawing the `latitude lines' on the femoral condyles at different degrees of knee flexion, corresponding to the anterior edge of the tibial articular surface as the reference point. This Knee Diagram using the tibial articular margin as a reference point, is not only useful for the accurate representation of the arthroscopic knee findings but also the most useful way to correlate the MRI findings of the femoral cartilage defect with the arthroscopic findings. Most useful of all are the reference latitude lines of the femoral condyles that remain a fixed landmark for that particular knee and thus helps to locate the same lesion at repeated arthroscopic evaluations, by different observers. A grid on the diagram helps to map the cartilage defect in millimetres. In this era of research on cartilage grafting, we think this Knee Diagram will be particularly useful to document and follow-up knee lesions in a more scientific way.