Ultrasound based muscle kinematics measurement with tracklet stitching

The objective of this study is to develop and validate an ultrasound (US) tissue tracking algorithm for measuring muscle velocity. This algorithm is designed to (1) be applicable to a wide variety of muscles, (2) overcome the limitations of previously published methods that required visualization of complete muscle fascicles, and (3) use B-mode imagery from commercially-available equipment that can be applied in a clinical office-type setting. This is accomplished by combining multiple block based tracking methods and filtering their output tracklets to create a velocity estimate. The algorithm was validated with a combination of Field II and in vivo MR velocity measurements. The average rectus femoris displacement error for the US data (average of 12 cycles) ranged from 0.7 to 6.4mm for flexion displacement and from 1.4 to 8.0mm during extension.