Development and Validation of a Finite Element Model of the Superior Glenoid Labrum

University of Michigan, Ann Arbor, 48109, USA.
Annals of Biomedical Engineering (Impact Factor: 3.23). 12/2010; 38(12):3766-76. DOI: 10.1007/s10439-010-0105-4
Source: PubMed


Pathology of the superior glenoid labrum is a common source of musculoskeletal pain and disability. One of the proposed mechanisms of injury to the labrum is superior humeral head migration, which can be seen with rotator cuff insufficiency. Due to the size, anatomical location, and complex composition of the labrum, laboratory experiments have many methodological difficulties. The purpose of this study was to develop and validate a finite element model of the glenoid labrum. The model developed includes the glenoid labrum, glenoid cartilage, glenoid bone, and the humeral head cartilage. Labral displacements derived from the finite element model were compared to those measured during a controlled validation experiment simulating superior humeral head translations of 1, 2, and 3 mm. The results of the finite element model compared well to experimental measurements, falling within one standard deviation of the experimental data in most cases. The model predicted maximum average strains in the superior labrum of 7.9, 10.1, and 11.9%, for 1, 2, and 3 mm of humeral translation, respectively. The correspondence between the finite element model and the validation experiment supports the use of this model to better understand the pathomechanics of the superior labrum.

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    • "The average strain for stable versus unstable shoulders was 10% and 17%, respectively. A previous computational labral model reported strains of 14% at 3 mm without consideration of the LHBT, after conversion from a logarithmic strain to the Green strain (Gatti et al., 2010). In contrast, the mean strain at failure was reported for the human shoulder labrum as approximately 40% (Smith et al., 2008), and from the human hip labrum as approximately 50% (Ishiko et al., 2005). "
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