Feasibility of using a video-based motion analysis system for measuring thumb kinematics.
While several different methods have been used to measure hand kinematics, fluoroscopy is generally considered to be the most accurate. Recently, video-based motion analysis has been developed for the measurement of joint kinematics. This method is versatile, easy to use, and can measure motions dynamically. Surface markers are most commonly used in the video-based motion systems. However, whether the surface markers placed on the thumb accurately represent the true kinematics of the underlying bony segment is questionable. In this study, the feasibility of surface markers to represent thumb kinematics was investigated by fluoroscopy. Both the positions of surface markers and bony landmarks were simultaneous recorded and then digitized. The Ra(2) values comparing the angular changes of the thumb interphalangeal, metacarpal and carpometacarpal joints derived using the surface markers or bony landmarks were 0.9986, 0.9730 and 0.9186 in the flexion/extension plane respectively, 0.8837, 0.9697 and 0.8775 in the abduction/adduction plane; and 0.9884, 0.9643 and 0.9431 in the opposition plane. The ranges, mean and standard deviation of the absolute differences between calculated angles of different marker sets were also compared. These data revealed that the similarities of the two different marker techniques throughout the motion cycle were high. The differences between the two methods were also within clinically allowable range of +/-5 degrees. It is concluded that the application of the video-based motion analysis system with surface markers to thumb kinematics is warranted.
Kuo
Li-Chieh
LC
Institute of Biomedical Engineering, National Cheng Kung University, Tainan, Taiwan.
Su
Fong-Chin
FC
Chiu
Haw-Yen
HY
Yu
Chin-Yin
CY
D000328:Adult; D001696:Biomechanical Phenomena; D005240:Feasibility Studies; D005260:Female; D005384:Finger Joint / Q000000981:diagnostic imaging / Q000502:physiology; D005471:Fluoroscopy / Q000379:methods*; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000295:instrumentation / Q000379:methods*; D008297:Male; D009068:Movement / Q000502:physiology; D011856:Radiographic Image Enhancement / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013933:Thumb / Q000000981:diagnostic imaging* / Q000502:physiology*; D014742:Videodisc Recording / Q000379:methods*