The overall goal of this revision application is to build an interdisciplinary research team with the goal to validate and utilize a new assay for quantifying the organization of collagen within tendon that can ultimately be translated into an in vivo diagnostic tool. The goal of the parent grant is to elucidate the mechanisms governing the relationships between tendon injury and joint damage. Specifically, the hypothesis is that an increase in joint damage will be explained by overuse activity and tendon force couple disruption. Two main clinical scenarios which were outlined in the parent grant are directly addressed in these studies. The first describes an active individual with a supraspinatus tendon tear, who would like to be advised if she can return to her previous high level of activity without causing long term damage. The second describes a laborer with a chronic tear involving the supraspinatus and the infraspinatus tendons. He would like to know if he can maintain his current level of activity without surgical intervention, or if re- attachment of the infraspinatus tendon to balance the disrupted force couple is needed to prevent joint damage. The parent grant uses an established rat rotator cuff injury model to study the biological and mechanical properties of the cartilage and intact tendons after a rotator cuff injury following a return to overuse activity or return to cage activity to determine which clinical scenarios cause long term joint damage. While this grant provides invaluable information about the mechanism of joint damage, the methods employed are destructive, and as such, cannot be translated into clinical assays. The specific goal of this revision application is to quantify the structural changes in the biceps tendon caused by returning to overuse activity following a SI tear using HFUS imaging. These HFUS measures will be correlated to measures of collagen organization from our previously established polarized light method, which would validate the use of this technique. If we are able to show that these measurements of collagen organization support the mechanical findings of the parent grant, this method would ultimately result in a powerful and reliable method for non-invasively monitoring tendon health or damage accumulation for this and other studies, as well as providing a clinically transferable diagnostic tool.

Public Health Relevance

The overall goal of this revision application is to build an interdisciplinary research team with the goal to validate and utilize a new assay for quantifying the organization of collagen within tendon that can ultimately be translated into an in vivo diagnostic tool. The specific goal of this revision application is to quantify the structural changs in the biceps tendon caused by returning to overuse activity following a combined supraspinatus and infraspinatus rotator cuff tear in a rat model using high-frequency ultrasound imaging. These imaging measures will be correlated to measures of collagen organization from our polarized light method, which would validate the use of this technique.

Agency
National Institute of Health (NIH)
Institute
National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)
Type
Research Project (R01)
Project #
3R01AR056658-04S1
Application #
8582680
Study Section
Special Emphasis Panel (ZAR1-KM (M1))
Program Officer
Tyree, Bernadette
Project Start
2013-09-01
Project End
2015-01-31
Budget Start
2013-09-01
Budget End
2014-01-31
Support Year
4
Fiscal Year
2013
Total Cost
$29,376
Indirect Cost
$11,016
Name
University of Pennsylvania
Department
Orthopedics
Type
Schools of Medicine
DUNS #
042250712
City
Philadelphia
State
PA
Country
United States
Zip Code
19104
Reuther, Katherine E; Thomas, Stephen J; Tucker, Jennica J et al. (2015) Overuse activity in the presence of scapular dyskinesis leads to shoulder tendon damage in a rat model. Ann Biomed Eng 43:917-28
Thomas, Stephen J; Reuther, Katherine E; Tucker, Jennica J et al. (2014) Biceps detachment decreases joint damage in a rotator cuff tear rat model. Clin Orthop Relat Res 472:2404-12
Reuther, Katherine E; Thomas, Stephen J; Tucker, Jennica J et al. (2014) Disruption of the anterior-posterior rotator cuff force balance alters joint function and leads to joint damage in a rat model. J Orthop Res 32:638-44
Reuther, Katherine E; Thomas, Stephen J; Tucker, Jennica J et al. (2014) Scapular dyskinesis is detrimental to shoulder tendon properties and joint mechanics in a rat model. J Orthop Res 32:1436-43
Reuther, Katherine E; Thomas, Stephen J; Sarver, Joseph J et al. (2013) Effect of return to overuse activity following an isolated supraspinatus tendon tear on adjacent intact tendons and glenoid cartilage in a rat model. J Orthop Res 31:710-5
Reuther, Katherine E; Thomas, Stephen J; Evans, Elisabeth F et al. (2013) Returning to overuse activity following a supraspinatus and infraspinatus tear leads to joint damage in a rat model. J Biomech 46:1818-24
Hsu, Jason E; Reuther, Katherine E; Sarver, Joseph J et al. (2011) Restoration of anterior-posterior rotator cuff force balance improves shoulder function in a rat model of chronic massive tears. J Orthop Res 29:1028-33
Peltz, Cathryn D; Hsu, Jason E; Zgonis, Miltiadis H et al. (2011) Decreased loading after rotator cuff tears leads to improved biceps tendon properties in a rat model. J Shoulder Elbow Surg 20:698-707
Peltz, Cathryn D; Hsu, Jason E; Zgonis, Miltiadis H et al. (2010) The effect of altered loading following rotator cuff tears in a rat model on the regional mechanical properties of the long head of the biceps tendon. J Biomech :