Reconstruction of skeletal movement using skin markers: comparative assessment of bone pose estimators
Tóm tắt
The assessment of the accuracy of the pose estimation of human bones and consequent joint kinematics is of primary relevance in human movement analysis. This study evaluated the performance of selected pose estimators in reducing the effects of instrumental errors, soft tissue artifacts and anatomical landmark mislocations occurring at the thigh on the determination of the knee kinematics. The pattern of a typical knee flexion-extension during a gait cycle was fed into a knee model which generated a six-components knee kinematics and relevant marker trajectories. The marker trajectories were corrupted with both instrumental noise and soft tissue artifacts. Two different cluster configurations (4 and 12-marker cluster) were investigated. Four selected pose estimators, a Geometrical method, a SVD-based method, and the Pointer Cluster Technique in the optimized and non optimized version, were analyzed. The estimated knee kinematics were compared to the nominal kinematics in order to evaluate the accuracy of the selected pose estimators. Results have shown that optimal pose estimators perform better than traditional geometric pose estimators when soft tissue artifacts are present. The use of redundant markers improved in some cases the estimation of the dynamics of the kinematics patterns, while it does not reduce the offsets from the nominal kinematics curves. Overall, the best performance was obtained by the SVD-based pose estimator, while the performance of the PCT pose estimator in its optimal version was not satisfactory. However, the knee kinematics errors reached 5 deg for rotations and 10 mm for translations). Given the favorable experimental conditions of this study (soft tissue artifacts determined from a young, healthy and non overweight subject), the errors found in estimating the knee kinematics have to be considered unsatisfactory even if the best performing pose estimator is used. Therefore, it is the authors' opinion that the movement analysis research community should make additional efforts in the search of more subject specific error models to increase the accuracy of joint kinematics estimations.
Tài liệu tham khảo
Cappozzo A, Catani F, Della Croce U, Leardini A: Position and orientation in space of bones during movement: anatomical frame definition and determination. Clin Biomech (Bristol, Avon) 1995, 10: 171-178. 10.1016/0268-0033(95)91394-T
Cappozzo A, Della Croce U, Leardini A, Chiari L: Human movement analysis using stereophotogrammetry. Part 1: theoretical background. Gait Posture 2005, 21: 186-196.
Chiari L, Della Croce U, Leardini A, Cappozzo A: Human movement analysis using stereophotogrammetry. Part 2: instrumental errors. Gait Posture 2005, 21: 197-211. 10.1016/j.gaitpost.2004.04.004
Leardini A, Chiari L, Della Croce U, Cappozzo A: Human movement analysis using stereophotogrammetry. Part 3. Soft tissue artifact assessment and compensation. Gait Posture 2005, 21: 212-225. 10.1016/j.gaitpost.2004.05.002
Della Croce U, Leardini A, Chiari L, Cappozzo A: Human movement analysis using stereophotogrammetry. Part 4: assessment of anatomical landmark misplacement and its effects on joint kinematics. Gait Posture 2005, 21: 226-237. 10.1016/j.gaitpost.2004.05.003
Cappozzo A, Catani F, Leardini A, Benedetti MG, Della Croce U: Position and orientation in space of bones during movement: experimental artefacts. Clin Biomech (Bristol, Avon) 1996, 11: 90-100. 10.1016/0268-0033(95)00046-1
Della Croce U, Camomilla V, Leardini A, Cappozzo A: Femoral anatomical frame: assessment of various definitions. Med Eng Phys 2003, 25: 425-431. 10.1016/S1350-4533(03)00032-8
Veldpaus FE, Woltring HJ, Dortmans LJ: A least-squares algorithm for the equiform transformation from spatial marker co-ordinates. Journal of Biomechanics 1988, 21: 45-54. 10.1016/0021-9290(88)90190-X
Arun KS, Huang TS, Blostein SD: Least-Squares Fitting of 2 3-D Point Sets. IEEE Trans Pattern Anal Mach Intell 1987, 9: 699-700.
Soderkvist I, Wedin PA: Determining the movements of the skeleton using well-configured markers. Journal of Biomechanics 1993, 26: 1473-1477. 10.1016/0021-9290(93)90098-Y
Challis JH: An examination of procedures for determining body segment attitude and position from noisy biomechanical data. Medical Engineering & Physics 1995, 17: 83-90. 10.1016/1350-4533(95)91877-J
Cappozzo A, Cappello A, Della Croce U, Pensalfini F: Surface-marker cluster design criteria for 3-D bone movement reconstruction. IEEE Trans Biomed Eng 1997, 44: 1165-1174. 10.1109/10.649988
Cheze L, Fregly BJ, Dimnet J: A solidification procedure to facilitate kinematic analyses based on video system data. Journal of Biomechanics 1995, 28: 879-884. 10.1016/0021-9290(95)95278-D
Cappello A, La Palombara PF, Leardini A: Optimization and smoothing techniques in movement analysis. Int J Bio-Med Comput 1996, 41: 137-151. 10.1016/0020-7101(96)01167-1
Andriacchi TP, Alexander EJ, Toney MK, Dyrby C, Sum J: A point cluster method for in vivo motion analysis: applied to a study of knee kinematics. Journal of Biomechanical Engineering 1998, 120: 743-749. 10.1115/1.2834888
Camomilla V, Donati M, Cappozzo A: Non-invasive soft tissue artefact assessment: September 5-7th 2005; University of Salford, Salford. ; 2005:80-81.
Cappello A, Stagni R, Fantozzi S, Leardini A: Soft tissue artifact compensation in knee kinematics by double anatomical landmark calibration: performance of a novel method during selected motor tasks. IEEE Trans Biomed Eng 2005, 52: 992-998. 10.1109/TBME.2005.846728
Alexander EJ, Andriacchi TP: Correcting for deformation in skin-based marker systems. Journal of Biomechanics 2001, 34: 355-361. 10.1016/S0021-9290(00)00192-5
Carman AB, Milburn PD: Determining rigid body transformation parameters from ill-conditioned spatial marker co-ordinates. Journal of Biomechanics 2005., In Press, available online:
Gill HS, O'Connor JJ: Biarticulating two-dimensional computer model of the human patellofemoral joint. Clinical Biomechanics 1996, 11: 81-89. 10.1016/0268-0033(95)00021-6
Camomilla V, Cereatti A, Vannozzi G, Cappozzo A: An optimized protocol for hip joint centre determination using the functional method. J Biomech 2005, 39: 1096-106. 10.1016/j.jbiomech.2005.02.008
Grood ES, Suntay WJ: A joint coordinate system for the clinical description of three-dimensional motions: application to the knee. Journal of Biomechanical Engineering 1983, 105: 136-144.