Much research is ongoing into improving the accuracy of functional algorithms to determine joint centers (JC), but there has been limited testing using human movement data. This paper is in three parts: Part 1, errors in determining JCs from real human movement data using the SCoRE method; Part 2, variability of marker combinations during a punch; Part 3, variability in the JC due to reconstruction. Results indicate determining the JC of the shoulder or elbow with a triad of markers per segment with an accuracy greater than 20 mm is unlikely. Part 2 suggests conducting a pilot study with abundant markers to obtain triads, which are most stable due to differences of 300–400% in variability between triads. Variability due to the choice of reference frame for reconstruction during the punch ranged from 2.5 to 13.8 mm for the shoulder and 1.5 to 21.1 mm for the elbow. It would appear more pertinent to enhance the practical methods in situ than to further improve theoretical accuracy of functional methods.
Andy Roosen, Matthew T.G. Pain and Mickaël Begon
Jonathan Sinclair, Jack Hebron and Paul J. Taylor
The principal source of measurement error in three-dimensional analyses is the definition of the joint center about which segmental rotations occur. The hip joint has received considerable attention in three-dimensional modeling analyses yet the reliability of the different techniques for the definition of the knee joint center has yet to be established. This study investigated the reliability of five different knee joint center estimation techniques: femoral epicondyle, femoral condyle, tibial ridge, plugin-gait, and functional. Twelve male participants walked at 1.25 m·s−1 and three-dimensional kinetics/kinematics of the knee and ankle were collected. The knee joint center was defined twice using each technique (test-and-retest) and the joint kinetic/kinematic data were applied to both. Wilcoxon rank tests and intraclass correlation coefficients (ICCs) were used to compare test and retest angular parameters and kinematic waveforms. The results show significant differences in coronal and transverse planes angulation using the tibial ridge, plug-in-gait, and functional methods. The strongest test-retest ICCs were observed for the femoral epicondyle and femoral condyle configurations. The findings from the current investigation advocate that the femoral epicondyle and femoral condyle techniques for the estimation of the knee joint center are currently the most reliable techniques.
Antoine Falisse, Sam Van Rossom, Johannes Gijsbers, Frans Steenbrink, Ben J.H. van Basten, Ilse Jonkers, Antonie J. van den Bogert and Friedl De Groote
. Kainz et al 18 found that Harrington equations are more accurate than other regression equations, but they suggest the use of functional methods, such as geometric sphere fitting methods, 19 , 20 in people with sufficient active hip range of motion, such as the subjects in this study. More accurate
Rienk M.A. van der Slikke, Annemarie M.H. de Witte, Monique A.M. Berger, Daan J.J. Bregman and Dirk Jan H.E.J. Veeger
-class athletes with sometimes affected hand grip functionality. Methods Subjects The WMP was measured in a standardized field test 10 for 20 elite level wheelchair basketball athletes. Athletes played at international (n = 7) or national level (n = 13; Dutch competition), with a group of 10 players of class 1
Katie A. Conway and Jason R. Franz
. PubMed ID: 25931719 doi:10.1589/jpts.27.733 10.1589/jpts.27.733 Piazza , S.J. , Okita , N. , & Cavanagh , P.R. ( 2001 ). Accuracy of the functional method of hip joint center location: Effects of limited motion and varied implementation . Journal of Biomechanics, 34 ( 7 ), 967 – 973 . PubMed
Katie A. Conway, Randall G. Bissette and Jason R. Franz
– 254 . PubMed ID: 12687518 doi:10.1002/art.11005 12687518 10.1002/art.11005 23. Piazza SJ , Okita N , Cavanagh PR . Accuracy of the functional method of hip joint center location: effects of limited motion and varied implementation . J Biomech . 2001 ; 34 ( 7 ): 967 – 973 . PubMed ID