Biomedical subjects

Li-Chieh Kuo

Publications and source records attributed to Li-Chieh Kuo.

6 recordsLinked to original sources

PubMed2006

The feasibility of a video-based motion analysis system in measuring the segmental movements between upper and lower cervical spine.

The evaluation of the range of motion (ROM) and static posture in the cervical spine are important in physical examination. Despite offering dynamic assessment without radiation, the video-based motion analysis system has not yet been applied to measure the cervical segmental movements. The purposes of this study were to develop a neck model to differentiate the movements and posture between upper and lower cervical spine, and to examine the reliability of measuring cervical motion with surface markers and the aid of videofluoroscopy. Sixteen healthy adult subjects (eight males and eight females) participated in this study. Ten surface markers were used to estimate the discrepancies in cervical vertebral angles compared with corresponding bony landmarks throughout the ROM. The average intraclass correlation coefficients (ICCs) of the paired vertebral angles between surface markers and bony landmarks ranged from 0.844 to 0.975 and the mean absolute difference (MAD) averaged 2.96 degrees. Our results indicate high consistency between surface markers and bony landmarks throughout the cervical movements. The mean upper (C0-C2) and lower (C2-C7) cervical joint angles in the neutral position were 18.59+/-4.33 degrees and 23.98+/-6.15 degrees, respectively. Furthermore, the reliability of the digitizing procedure within raters (ICC=0.850-0.999; MAD=0.58-2.42 degrees) and between raters (ICC=0.759-0.988; MAD=0.59-2.66 degrees) suggests that the neck motion analysis model is a feasible method for investigating static neck posture or dynamic motion between upper and lower cervical spine.

Adult↗

PubMed2004

A quantitative method to measure maximal workspace of the trapeziometacarpal joint--normal model development.

INTRODUCTION: A reliable and quantitative method for measuring motion of the thumb is lacking. In particular, review of the previous methods of motion analysis of the thumb joints shows that there is no objective method for clinicians to assess the impairment of the thumb trapeziometacarpal (TMC) joint. Based on the concept of the three-dimensional (3-D) space within which the first metacarpal can move relative to the trapezium (a concept of defining and measuring the workspace of the TMC motion), we present a quantitative method for measuring motion and impairment (loss of function) of the TMC joint. METHODS: Twenty normal subjects were recruited in this study. An electromagnetic device was placed over the thumb metacarpal and long finger metacarpal, the 3-D relationship between them previously established. We measured the position and orientation of the TMC motion in space. Maximum movements of the thumb TMC joint in circumduction, flexion-extension and abduction-adduction were used to construct the 3-D maximal workspace of the TMC joint. Mathematical methods were used to verify the model and calculate the maximal workspace. RESULTS: The results of this study demonstrate accurate and repeatable measurement of 3-D TMC motion with high statistical reliability and low variability of the maximal TMC workspace. A statistically significant linear correlation between the maximal surface area and the square of the first metacarpal length was obtained. CONCLUSION: We conclude that a quantitatively comparative measurement of the range of motion of the TMC joint can be obtained with potential to measure motion in joints affected by arthritis or trauma and measured in both dynamic and static positions of the thumb.

Adult↗

PubMed2004

A kinematic method to calculate the workspace of the trapeziometacarpal joint.

The specific aim of this study was to develop a quantitative method and a kinematic method to evaluate the maximal workspace of the trapeziometacarpal (TM) joint. Six fresh-frozen human cadaver hands were disarticulated 4 cm proximal to the wrist joint and used in this experiment. The three-dimensional motion data of the TM joint was collected by an electromagnetic tracking device at 30 Hz. The workspace was reconstructed according to a complete set of motion data included circumduction, flexion-extension and abduction-adduction. A spherical fitting technique was used to obtain a sphere encompassing all the motion trajectories and estimating the centre of the sphere. The surface area of the maximal TM workspace, located on the one part of the sphere surface, was calculated by surface integration. The interclass correlation coefficient values for the reliability estimation of the repeated measurements of the radius and surface area of all specimens were 0.91 and 0.98 respectively. The mean coefficients of variance of the measured radius and the surface area were 2.04 per cent and 3.65 per cent respectively. The results also showed that using a spherical model to calculate the maximal workspace as an index for assessing TM joint impairment is practical.

Adolescent↗

PubMed2003

Video-computer quantitative evaluation of thumb function using workspace of the thumb.

This study develops the basis for video-computer quantitative evaluation method for measuring degree of thumb impairment. The system evaluates the three-dimensional space (workspace) within which the thumb-tip moves and computes its surface area. This study is intended to be the basis of a subsequent study which will compute the percentage of actual use compared to the "ideal" value for the given thumb length. Based on this quantitative measurement, the movement function of the impaired thumb can be identified objectively. Repeatability testing confirms that the video motion analysis system is a reliable tool for measuring the workspace of thumb-tip motion. It is also shown experimentally that there is a linear correlation between the surface area of thumb-tip motion workspace and the square of the thumb length. Accordingly, this method may be used to evaluate the functional abnormalities and deformities of the thumb.

Adolescent↗

PubMed2003

Feasibility of using surface markers for assessing motion of the thumb trapeziometacarpal joint.

OBJECTIVE: The purposes of the present study were to investigate the feasibility of using a skin sensor to represent the first and third metacarpal bone, to verify that there was no significant relative motion between the skin of the third metacarpal bone and trapezium bony segment and to measure thumb metacarpal motion with respect to the hand (third metacarpal). DESIGN: Eight hands from fresh-frozen human cadavers were disarticulated 4 cm proximal to the wrist joint and used in this experiment. BACKGROUND: Recently, magnetic-tracking systems have been developed for the measurement of joint kinematics. Based on the concept of the three-dimensional space within which the thumb metacarpal bone can move, the current study proposes a 3D method for evaluating the relationship between the skin and bony segment. METHODS: An electromagnetic tracking system was used to provide quantitative measurement and evaluation of the relationship between the skin and bony segment while moving the trapeziometacarpal joint. RESULTS: The adjusted coefficient of multiple determination, R(a)(2), values of the kinematic waveforms between the sensors were larger than 0.84. The angular differences and displacements of the center of sensors between the skin and bony sensors were less than 4.9 degrees and 2.8 mm. CONCLUSION: These data revealed that the similarities of the two sensors throughout the motion cycle were high. The differences between the two sensors were also within the clinically allowable range of +/-5 degrees. Therefore, it is feasible to collect motions of the first metacarpal by attaching the skin sensors at the metacarpal head to measure the bony segment.

Aged↗

PubMed2002

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.

Adult↗