title: Analysis of the Constraint Joint Loading in the Thumb During Pipetting.
abstract: Dynamic loading on articular joints is essential for the evaluation of the risk of the articulation degeneration associated with occupational activities. In the current study, we analyzed the dynamic constraint loading for the thumb during pipetting. The constraint loading is considered as the loading that has to be carried by the connective tissues of the joints (i.e., the cartilage layer and the ligaments) to maintain the kinematic constraints of the system. The joint loadings are solved using a classic free-body approach, using the external loading and muscle forces, which were obtained in an inverse dynamic approach combined with an optimization procedure in anybody. The constraint forces in the thumb joint obtained in the current study are compared with those obtained in the pinch and grasp tests in a previous study (Cooney and Chao, 1977, "Biomechanical Analysis of Static Forces in the Thumb During Hand Function," J. Bone Joint Surg. Am., 59(1), pp. 27-36). The maximal compression force during pipetting is approximately 83% and 60% greater than those obtained in the tip pinch and key pinch, respectively, while substantially smaller than that obtained during grasping. The maximal lateral shear force is approximately six times, 32 times, and 90% greater than those obtained in the tip pinch, key pinch, and grasp, respectively. The maximal dorsal shear force during pipetting is approximately 3.2 and 1.4 times greater than those obtained in the tip pinch and key pinch, respectively, while substantially smaller than that obtained during grasping. Our analysis indicated that the thumb joints are subjected to repetitive, intensive loading during pipetting, compared to other daily activities.
authors.forename: John Z
authors.initials: JZ
authors.lastname: Wu
authors.forename: Erik W
authors.initials: EW
authors.lastname: Sinsel
authors.forename: Kristin D
authors.initials: KD
authors.lastname: Zhao
authors.forename: Kai-Nan
authors.initials: KN
authors.lastname: An
authors.forename: Frank L
authors.initials: FL
authors.lastname: Buczek
mesh_terms: D001696:Biomechanical Phenomena; D052737:Carpometacarpal Joints / Q000502:physiology*; D018737:Hand Strength / Q000502:physiology*; D006801:Humans; D013933:Thumb / Q000502:physiology*; D016474:Weight-Bearing
references.citation: Med Eng Phys. 2012 Jul;34(6):693-701
references.pmid: 22015316
references.citation: Am J Epidemiol. 2002 Dec 1;156(11):1021-7
references.pmid: 12446258
references.citation: Clin Biomech (Bristol, Avon). 2011 May;26(4):371-6
references.pmid: 21146265
references.citation: Ergonomics. 2008 Jun;51(6):843-57
references.pmid: 18484399
references.citation: Clin J Sport Med. 2010 Mar;20(2):106-12
references.pmid: 20215892
references.citation: Semin Arthritis Rheum. 2010 Jun;39(6):465-76
references.pmid: 19482338
references.citation: Osteoarthritis Cartilage. 2006 Sep;14(9):953-7
references.pmid: 16759885
references.citation: Hum Factors. 2005 Spring;47(1):67-76
references.pmid: 15960087
references.citation: Ann Rheum Dis. 2005 May;64(5):682-7
references.pmid: 15374852
references.citation: Rheumatology (Oxford). 2005 Apr;44(4):521-8
references.pmid: 15728421
references.citation: Acta Chir Scand. 1953 Oct 29;106(2-3):166-86
references.pmid: 13137829
references.citation: J Hand Surg Am. 1999 Jul;24(4):786-98
references.pmid: 10447171
references.citation: AAOHN J. 1996 Oct;44(10):487-92
references.pmid: 9043212
references.citation: J Orthop Res. 1995 May;13(3):450-8
references.pmid: 7602407
references.citation: Ergonomics. 1995 May;38(5):1067-73
references.pmid: 7737101
references.citation: J Hand Surg Am. 1991 Nov;16(6):967-74
references.pmid: 1748767
references.citation: Arthritis Rheum. 1978 Mar;21(2):210-20
references.pmid: 637887
references.citation: J Bone Joint Surg Am. 1977 Jan;59(1):27-36
references.pmid: 833171
references.citation: Arthritis Rheum. 2003 Apr;48(4):1034-40
references.pmid: 12687546
references.citation: J Biomech. 2014 Jan 22;47(2):392-9
references.pmid: 24290720
references.citation: Clin J Sport Med. 2013 Jul;23(4):247-54
references.pmid: 23615487
references.citation: J Hand Surg Am. 2013 Mar;38(3):532-6
references.pmid: 23375785
references.citation: J Orthop Sports Phys Ther. 2003 Jul;33(7):386-99
references.pmid: 12918864
references.citation: J Biomech. 2011 Jun 3;44(9):1805-9
references.pmid: 21530970