Quantifying dynamic joint stability of foot joints during walking using bi-planar fluoroscopic images

Abstract

Many surgical treatments have been developed to improve the mobility and stability of the foot joint. Among these, resection of the talocalcaneal coalition to relieve the symptoms and reconstruct joint mobility of subtalar joint, and modified Broström procedure to relieve the symptoms and treat chronic ankle instability. Many studies have been conducted to confirm the effectiveness of these surgical methods using many qualitative methods to evaluate foot stability. At this time, as the method for acquiring the kinematics of the foot bone and foot joints developed, studies to analyze the effect of the above surgical methods on the foot joint motion have also been conducted. However, the above studies had some limitations, such as analyzing the effect of surgery on only a single joint motion, analyzing only the shape of a joint in a fixed posture, or analyzing joint movement through a marker-based method. Therefore, in this study, the kinematics of the ankle joint, the subtalar joint, and the tibiocalcaneal joint during walking before and after surgery were evaluated using a bi-plane fluoroscopy device in the patient group who underwent talocalcaneal coalition resection and the modified Broström procedures. The effect of each operation on joint movement was analyzed by calculating and comparing the movement of the joint before and after the surgery. In addition, in order to develop an algorithm for acquiring accurate joint motion using data obtained from a bi-plane fluoroscopy device, an method to calculate the initial 3D bone position based on bone feature factors, and the restriction of the degree of freedom on each foot bone using the foot bone pose model, and the method of improving accuracy and reducing the time required for the optimization process based on the restriction of motion variety through close frame were presented. The accuracy of proposed method was validated using the manual registration joint motion data.