3D tendon strain estimation on high-frequency 3D ultrasound images a simulation and phantom study

Tendon strain is a topic of interest within the orthopaedics and sports medicine community. If accurately estimated, it can improve existing treatment and rehabilitation protocols and aid in detection of presymptomatic abnormalities. This paper presents a novel US-based strain estimation framework that integrates an affine image registration approach to quantify tendon strain with a high-resolution 3D US imaging system. Validation of this framework was performed on simulated and phantom data. An accuracy test of the acquisition system and the performance of 3D and 2D strain estimations were evaluated. Results show that attention should be paid to the acquisition protocol, best accuracy is obtained for simulation data and along the major deformation direction and 3D strain estimations seems to reduce out-of-plane effect. By using this technique, it is expected that clinicians expand knowledge on aetiology of tendinopathy and optimize the existing therapeutic programs. Furthermore this technique can be extrapolated to other tendons and ligaments that are vulnerable to overuse.