The inwardly pointing knee angle: A novel computed tomography-based measurement technique and validation study

Purpose

Inwardly pointing knee (IPK) is a clinically recognized manifestation of torsional malalignment in patients with patellofemoral pain and instability. However, current imaging protocols primarily quantify isolated components of malalignment, such as femoral anteversion or tibial torsion, without also capturing the net orientation of the knee relative to the direction of gait. The purposes of this study were to describe a functional computed tomography (CT) protocol for patellofemoral assessment and to introduce and validate the measurement of the inwardly pointing knee angle (IPKA).