title: In Vivo Measures of Shear Wave Speed as a Predictor of Tendon Elasticity and Strength.
abstract: The purpose of this study was to assess the potential for ultrasound shear wave elastography (SWE) to measure tissue elasticity and ultimate stress in both intact and healing tendons. The lateral gastrocnemius (Achilles) tendons of 41 New Zealand white rabbits were surgically severed and repaired with growth factor coated sutures. SWE imaging was used to measure shear wave speed (SWS) in both the medial and lateral tendons pre-surgery, and at 2 and 4 wk post-surgery. Rabbits were euthanized at 4 wk, and both medial and lateral tendons underwent mechanical testing to failure. SWS significantly (p < 0.001) decreased an average of 17% between the intact and post-surgical state across all tendons. SWS was significantly (p < 0.001) correlated with both the tendon elastic modulus (r = 0.52) and ultimate stress (r = 0.58). Thus, ultrasound SWE is a potentially promising non-invasive technology for quantitatively assessing the mechanical integrity of pre-operative and post-operative tendons.
authors.affiliation: Materials Science Program, University of Wisconsin-Madison, Madison, Wisconsin, USA. Electronic address: jamartin8@wisc.edu.
authors.forename: Jack A
authors.initials: JA
authors.lastname: Martin
authors.affiliation: School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin, USA.
authors.forename: Adam H
authors.initials: AH
authors.lastname: Biedrzycki
authors.affiliation: Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin, USA.
authors.forename: Kenneth S
authors.initials: KS
authors.lastname: Lee
authors.affiliation: Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin, USA.
authors.forename: Ryan J
authors.initials: RJ
authors.lastname: DeWall
authors.affiliation: School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin, USA.
authors.forename: Sabrina H
authors.initials: SH
authors.lastname: Brounts
authors.affiliation: Materials Science Program, University of Wisconsin-Madison, Madison, Wisconsin, USA; Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, Wisconsin, USA; Department of Mechanical Engineering, University of Wisconsin-Madison, Madison, Wisconsin, USA.
authors.forename: William L
authors.initials: WL
authors.lastname: Murphy
authors.affiliation: School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin, USA.
authors.forename: Mark D
authors.initials: MD
authors.lastname: Markel
authors.affiliation: Materials Science Program, University of Wisconsin-Madison, Madison, Wisconsin, USA; Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, Wisconsin, USA; Department of Mechanical Engineering, University of Wisconsin-Madison, Madison, Wisconsin, USA.
authors.forename: Darryl G
authors.initials: DG
authors.lastname: Thelen
mesh_terms: D000818:Animals; D003198:Computer Simulation; D055119:Elastic Modulus; D005260:Female; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008297:Male; D008954:Models, Biological; D011817:Rabbits; D015203:Reproducibility of Results; D012542:Scattering, Radiation; D012680:Sensitivity and Specificity; D033081:Shear Strength; D013708:Tendon Injuries / Q000000981:diagnostic imaging* / Q000503:physiopathology* / Q000601:surgery; D013710:Tendons / Q000000981:diagnostic imaging* / Q000502:physiology* / Q000601:surgery; D013718:Tensile Strength; D000069453:Ultrasonic Waves; D014463:Ultrasonography / Q000379:methods*; D014945:Wound Healing / Q000502:physiology
keywords: Rabbit Achilles; Tendon repair; Tendon stiffness; Ultrasound shear wave elastography