Evaluation of equine articular cartilage degeneration after mechanical impact injury using cationic contrast-enhanced computed tomography

B B Nelson; J T A Mäkelä; T B Lawson; A N Patwa; M F Barrett; C W McIlwraith; M B Hurtig; B D Snyder; V J Moorman; M W Grinstaff; L R Goodrich; C E Kawcak

doi:10.1016/j.joca.2019.04.015

Evaluation of equine articular cartilage degeneration after mechanical impact injury using cationic contrast-enhanced computed tomography

Osteoarthritis Cartilage. 2019 Aug;27(8):1219-1228. doi: 10.1016/j.joca.2019.04.015. Epub 2019 May 8.

Authors

B B Nelson¹, J T A Mäkelä², T B Lawson³, A N Patwa⁴, M F Barrett⁵, C W McIlwraith¹, M B Hurtig⁶, B D Snyder⁷, V J Moorman¹, M W Grinstaff⁸, L R Goodrich¹, C E Kawcak⁹

Affiliations

¹ Equine Orthopaedic Research Center, Colorado State University, Fort Collins, CO, USA.
² Center for Advanced Orthopaedic Studies, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA; Department of Chemistry, Boston University, Boston, MA, USA.
³ Center for Advanced Orthopaedic Studies, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA; Department of Mechanical Engineering, Boston University, Boston, MA, USA.
⁴ Department of Chemistry, Boston University, Boston, MA, USA; SLSE (Chemistry), Navrachana University, Vadodara, Gujarat, India.
⁵ Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO, USA.
⁶ Department of Clinical Studies, University of Guelph, Ontario, Canada.
⁷ Center for Advanced Orthopaedic Studies, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA.
⁸ Department of Chemistry, Boston University, Boston, MA, USA; Department of Mechanical Engineering, Boston University, Boston, MA, USA; Departments of Biomedical Engineering, and Medicine, Boston University, Boston, MA, USA.
⁹ Equine Orthopaedic Research Center, Colorado State University, Fort Collins, CO, USA. Electronic address: ckawcak@colostate.edu.

PMID: 31075424
DOI: 10.1016/j.joca.2019.04.015

Abstract

Objective: Cationic agent contrast-enhanced computed tomography (cationic CECT) characterizes articular cartilage ex vivo, however, its capacity to detect post-traumatic injury is unknown. The study objectives were to correlate cationic CECT attenuation with biochemical, mechanical and histological properties of cartilage and morphologic computed tomography (CT) measures of bone, and to determine the ability of cationic CECT to distinguish subtly damaged from normal cartilage in an in vivo equine model.

Design: Mechanical impact injury was initiated in equine femoropatellar joints in vivo to establish subtle cartilage degeneration with site-matched controls. Cationic CECT was performed in vivo (clinical) and postmortem (microCT). Articular cartilage was characterized by glycosaminoglycan (GAG) content, biochemical moduli and histological scores. Bone was characterized by volume density (BV/TV) and trabecular number (Tb.N.), thickness (Tb.Th.) and spacing (Tb.Sp.).

Results: Cationic CECT attenuation (microCT) of cartilage correlated with GAG (r = 0.74, P < 0.0001), compressive modulus (E_eq) (r = 0.79, P < 0.0001) and safranin-O histological score (r = -0.66, P < 0.0001) of cartilage, and correlated with BV/TV (r = 0.37, P = 0.0005), Tb.N. (r = 0.39, P = 0.0003), Tb.Th. (r = 0.28, P = 0.0095) and Tb.Sp. (r = -0.44, P < 0.0001) of bone. Mean [95% CI] cationic CECT attenuation at the impact site (2215 [1987, 2443] Hounsfield Units [HUs]) was lower than site-matched controls (2836 [2490, 3182] HUs, P = 0.036). Clinical cationic CECT attenuation correlated with GAG (r = 0.23, P = 0.049), E_eq (r = 0.26, P = 0.025) and safranin-O histology score (r = -0.32, P = 0.0046).

Conclusions: Cationic CECT (microCT) reflects articular cartilage properties enabling segregation of subtly degenerated from healthy tissue and also reflects bone morphometric properties on CT. Cationic CECT is capable of characterizing articular cartilage in clinical scanners.

Keywords: Biochemical; Cartilage imaging; Glycosaminoglycan; Histology; Osteoarthritis; Post traumatic OA.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Cancellous Bone / diagnostic imaging
Cancellous Bone / pathology
Cartilage, Articular / diagnostic imaging*
Cartilage, Articular / injuries*
Cartilage, Articular / metabolism
Cartilage, Articular / pathology
Chondrocytes / pathology
Coloring Agents
Compressive Strength
Contrast Media
Glycosaminoglycans / metabolism
Horses
Magnetic Resonance Imaging
Models, Animal
Osteoarthritis, Knee
Phenazines
Stifle / injuries
Synovial Membrane / pathology
X-Ray Microtomography*

Substances

Coloring Agents
Contrast Media
Glycosaminoglycans
Phenazines
safranine T