Application of Ultrasound in Spine Kinematic Determination: A Systemic Review

Spine kinematic determination is required to diagnose or rehabilitate back pain due to spinal instability. Ultrasound imaging, as a less harmful and cost-effective method, has been recently applied to kinematic analysis. This study reviews all available published articles to see how much progress has been made in spine kinematic measurement by ultrasound. In this regard, we searched PubMed, Scopus, and Google Scholar among all available studies until 2021, using keywords such as ultrasound, spine, kinematics, rotation, twist, flexion, and bending. Finally, after identifying and scanning 183 articles, only nine articles were included, which analyzed spine kinematics by ultrasound. Among these nine articles, three reported axial displacements, three reported flexion/extension, and three reported axial rotation. Although ultrasound is a suitable alternative to other kinematic measurement methods, very little research and progress have been made in this area. Today, this method is still not used practically for spine kinematic measurement because the bone scans via ultrasound imaging are challenging to understand, and no three-dimensional kinematic measurement technique has been reported. However, recent advances in converting ultrasound images into three-dimensional images can pave the way for further improvements.