Objective To investigate the reliability and sensitivity of a three dimensional motion analysis system by using the segmental method.Methods Ten healthy young men participated in this study.They were asked to stand with one leg and with their eyes open and closed,respectively,each lasted for 30 seconds and was re- peated twice.According to the 12-segment rigid body model of the human body,twenty-one infrared light emitting di- ode(1RED)markers were placed over the bony prominences on the proximal and distal ends of each segment,the motion track of the IRED markers was recorded by the three dimensional motion analysis system.The mean sway am- plitude( MSA )and the sway path(SP)of the center of gravity(COG)were calculated.Correlation analysis was used to determine the reliability between the two repetitions.Paired sample t-test was used to determine the sensitivity be- tween the eyes open and closed conditions.Results The correlation coefficients of the MSA of the COG in the eyes open and closed conditions were 0.623 and 0.018,respectively,and the correlation coefficients of the SP of the COG were 0.936 and 0.654,respectively.It was also shown that significant differences existed among the three directions of the MSA of the COG and the SP of the COG.Conclusion Besides the weak reliability of the MSA of COG in the eyes closed condition,the high reliability and sensitivity of the MSA and SP of the COG are found.The segmental method can be used in the scientific study of human balance control.

Objective To provide theoretic base by studying the nature and characteristic of infrared ther- mograph in lower limbs area of the healthy young man.Methods Collecting infrared thermograph in lower limbs ar- ea by TIP medical infrared thermograpb instrument (TIP,made in USA) ,the average temperature of each unit area of both lower limbs was measured.Results (1) The average temperature of each corresponding unit area in both side of lower limbs was adjacent (P＜0.05 ).(2) The temperature of both lower limbs (especial front and back side) distributinged in some rule.Conclusion The study provided parameter and characteristic of infrared therrnograph for clinical diagnosis and guideline of rehabilitation therapy by infrared thermograph instrument.

Objective To provide an observational baseline by studying the nature and characteristics of in- frared thermograms of the spine area of the healthy young men.Methods Infrared thermograms of the spine area were collected using a TIP medical infrared thermograph.The average temperature of each unit area in the middle and on the two sides of the spine was measured.Results (1)Except certain unit areas in the cervical thorax and lum- bar sacral segments,the average temperature of each unit area in the middle of the spine was significantly higher than on the two sides.In the middle of the spine,the average temperature of the cervical thorax and lumbar sacral seg- ments was insignificantly higher than adjacent areas.The shape of the infrared thermograms of the cervical thorax and lumbar sacral segments resembled a triangle and a rhomboid,respectively.Conclusion The study provided para- meters and characteristics of infrared thermograms for clinical diagnosis and guidelines for rehabilitation therapy using an infrared thermograph.

OBJECTIVETo measure the axial rotation angles of the carpometacarpal joints during the digital opposition of thumb-index finger, thumb-medial finger, thumb-ring finger, thumb-little finger and the thumb's maximal opposition, then the application of these parameters were studied.

METHODSTwenty neutrality-occupation volunteers (female 10, male 10) with no history of hand injuries or related diseases were involved in the study. First, all the markers' 3-D coordinates were obstained using the 3D motion analysis system (EVaRT4.1) during the digital opposition movements of thumb. Then, the axial rotation angles were calculated.

RESULTSThe average rotation angles of carpometacarpal joints during all kinds of digital oppositions were 29.1 degrees +/- 9.4 degrees (male), 24.8 degrees +/- 10.2 degrees (female), while the maximal rotation angles are: 35.3 degrees (male), 28.8 degrees (female).

CONCLUSIONSThe combination of video-based 3-D analysis system and mathematics make it possible to measure the axial rotation angles of thumb in vivo, as a result, the rotation angles of thumb carpometacarpal joints are measured precisely for the first time. These results can provide a few parameters for treatment and rehabilitation of carpometacarpal arthrositis.

Adult ; Biomechanical Phenomena ; Female ; Finger Joint ; diagnostic imaging ; physiology ; Fluoroscopy ; instrumentation ; methods ; Humans ; Imaging, Three-Dimensional ; instrumentation ; methods ; Male ; Movement ; physiology ; Reproducibility of Results