TROCHLEAR GROOVE ALIGNMENT MEASUREMENT METHOD FOR SURGICAL APPLICATIONS

Abstract

In patellofemoral arthroplasty (PFA), rotational alignment is paramount for optimal patellofemoral function. Surgeons require a simple and effective measurement reference, through which the intact trochlear groove orientation can be quantified, to ensure good PFA alignment. We measured axial and coronal trochlear groove alignment in three-dimensional (3D) segmented computed tomography (CT) femurs relative to different references: The posterior condylar plane; the distal condylar plane, and the anatomical axis. The trochlear inclination angle (TIA) shows a better linear correlation with the axial groove angle when measured from the line perpendicular to the axial groove line as opposed to measurement from the posterior condylar plane. Similarly, a better linear correlation was achieved between the anatomical and the mechanical angles when measured from the coronal groove line as opposed to a line perpendicular to the distal condylar plane. Since axial and coronal groove alignment is quantifiable with respect to anatomical landmarks preoperatively, it may allow using the groove lines as a guideline for selection of the most appropriate patellofemoral prosthesis design. This may lead to the application of a PFA that better fits the patients' trochlear anatomy.