Strain-based methodology to assess the load transmitted into the clavicle during lateral shoulder impacts

Duprey, S.; Subit, D.; Rutherford, A.; Kent, R.

Affiliations

¹University of Virginia Center for Applied Biomechanics

Abstract

During car side impacts, the shoulder, especially the clavicle, is often injured. Determining the load transferred through the clavicle in situ during a shoulder lateral impact would allow a better understanding of shoulder injury mechanisms and of the role of the clavicle as a load path in this impact mode. The goal of this study was to develop a minimally invasive methodology to estimate the load transmitted into the clavicle during shoulder lateral impacts by measuring in situ strains.

Ten clavicles were harvested from six post-mortem human subjects (PMHS) and tested ex situ in compression with a device designed to mimic the anatomical boundary conditions in the shoulder. The compression was performed by imposing lateral and oblique displacement (up to ±25° off-axis) to the lateral extremity of the bone. The resulting forces and moments were measured as well as the strains by means of unidirectional strain gages pasted at different locations on the bone.

A linear relationship was observed between force and strain, regardless of the direction of the imposed displacement, and the angle of the imposed displacement was found to have almost no effect on the direction of the resulting force vector or on the slope of force-strain linear relationship. Based on these results, an empirical methodology is proposed to estimate the load transferred to the clavicle using in situ strain measurements.

Links

URL: http://www-nrd.nhtsa.dot.gov/pdf/bio/proceedings/2007_35/35-3.pdf

Cited Works (8)

Year	Entry
2004	Compigne S, Caire Y, Quesnel T, Verries J-P. Non-injurious and injurious impact response of the human shoulder three-dimensional analysis of kinematics and determination of injury threshold. Stapp Car Crash J. 2004;48:89-123. SAE 2004-22-0005.
1997	Frampton RJ, Morris AP, Thomas P, Bodiwala GG. An overview of upper extremity injuries to car occupants in UK vehicle crashes. In: Proceedings of the 1997 International IRCOBI Conference on the Biomechanics of Impact. September 24-26, 1997; Hannover, Germany.37-51.
2007	Hynd D, Carroll J, Cuerden R. Upper extremity injury study: recommendations for injury prevention priorities. In: Proceedings of the 20th International Technical Conference on the Enhanced Safety of Vehicles (ESV). June 18-21, 2007; Lyon, France.
1977	Rybicki EF, Mills EJ, Turner AS, Simonen FA. In vivo and analytical studies of forces and moments in equine long bones. J Biomech. 1977;10(11-12):701-705.
2000	Bolte JH IV, Hines MH, McFadden JD, Saul RA. Shoulder response characteristics and injury due to lateral glenohumeral joint impacts. Stapp Car Crash J. 2000;44:261-280. SAE 2000-01-SC18.
2005	Koh S-W, Cavanaugh JM, Mason MJ, Petersen SA, Marth DR, Rouhana SW, Bolte JH IV. Shoulder injury and response due to lateral glenohumeral joint impact: an analysis of combined data. Stapp Car Crash J. 2005;49:291-322. SAE 2005-22-0014.
2008	Duprey S, Bruyere K, Verriest J-P. Influence of geometrical personalization on the simulation of clavicle fractures. J Biomech. 2008;41(1):200-207.
1998	Melvin JW, Baron KJ, Little WC, Gideon TW, Pierce J. Biomechanical analysis of Indy race car crashes. In: Proceedings of the 42nd Stapp Car Crash Conference. November 2-4, 1998; Tempa, AZ. Warrendale, PA: Society of Automotive Engineers:247-266. SAE 983161.