Subject-specific musculoskeletal modeling in the evaluation of shoulder muscle and joint function.
Upper limb muscle force estimation using Hill-type muscle models depends on musculotendon parameter values, which cannot be readily measured non-invasively. Generic and scaled-generic parameters may be quickly and easily employed, but these approaches do not account for an individual subject's joint torque capacity. The objective of the present study was to develop a subject-specific experimental testing and modeling framework to evaluate shoulder muscle and joint function during activities of daily living, and to assess the capacity of generic and scaled-generic musculotendon parameters to predict muscle and joint function. Three-dimensional musculoskeletal models of the shoulders of 6 healthy subjects were developed to calculate muscle and glenohumeral joint loading during abduction, flexion, horizontal flexion, nose touching and reaching using subject-specific, scaled-generic and generic musculotendon parameters. Muscle and glenohumeral joint forces calculated using generic and scaled-generic models were significantly different to those of subject-specific models (p<0.05), and task dependent; however, scaled-generic model calculations of shoulder glenohumeral joint force demonstrated better agreement with those of subject-specific models during abduction and flexion. Muscles in generic musculoskeletal models operated further from the plateau of their force-length curves than those of scaled-generic and subject-specific models, while muscles in subject-specific models operated over a wider region of their force length curves than those of the generic or scaled-generic models, reflecting diversity of subject shoulder strength. The findings of this study suggest that generic and scaled-generic musculotendon parameters may not provide sufficient accuracy in prediction of shoulder muscle and joint loading when compared to models that employ subject-specific parameter-estimation approaches.
Department of Mechanical Engineering, University of Melbourne, Parkville, Victoria 3010, Australia.
Wen
W
Wu
Department of Mechanical Engineering, University of Melbourne, Parkville, Victoria 3010, Australia.
Peter V S
PVS
Lee
Department of Mechanical Engineering, University of Melbourne, Parkville, Victoria 3010, Australia.
Adam L
AL
Bryant
Department of Mechanical Engineering, University of Melbourne, Parkville, Victoria 3010, Australia.
Mary
M
Galea
Department of Mechanical Engineering, University of Melbourne, Parkville, Victoria 3010, Australia. Electronic address: dackland@unimelb.edu.au.
David C
DC
Ackland
D000203:Activities of Daily Living; D000328:Adult; D001696:Biomechanical Phenomena; D006801:Humans; D008297:Male; D008954:Models, Biological; D009068:Movement / Q000502:physiology; D018482:Muscle, Skeletal / Q000502:physiology*; D016059:Range of Motion, Articular / Q000502:physiology; D012782:Shoulder / Q000502:physiology*; D012785:Shoulder Joint / Q000502:physiology*; D019415:Torque
Biomechanical model; Glenohumeral; Musculotendon parameters; Upper limb