Skip to main content

Lund University Publications

LUND UNIVERSITY LIBRARIES

Subchondral bone plate thickness is associated with micromechanical and microstructural changes in the bovine patella osteochondral junction with different levels of cartilage degeneration

Das Gupta, Shuvashis LU orcid ; Workman, Joshua ; Finnilä, Mikko A.J. ; Saarakkala, Simo LU and Thambyah, Ashvin (2022) In Journal of the Mechanical Behavior of Biomedical Materials 129.
Abstract

The influence of joint degeneration on the biomechanical properties of calcified cartilage and subchondral bone plate at the osteochondral junction is relatively unknown. Common experimental difficulties include accessibility to and visualization of the osteochondral junction, application of mechanical testing at the appropriate length scale, and availability of tissue that provides a consistent range of degenerative changes. This study addresses these challenges. A well-established bovine patella model of early joint degeneration was employed, in which micromechanical testing of fully hydrated osteochondral sections was carried out in conjunction with high-resolution imaging using differential interference contrast (DIC) optical light... (More)

The influence of joint degeneration on the biomechanical properties of calcified cartilage and subchondral bone plate at the osteochondral junction is relatively unknown. Common experimental difficulties include accessibility to and visualization of the osteochondral junction, application of mechanical testing at the appropriate length scale, and availability of tissue that provides a consistent range of degenerative changes. This study addresses these challenges. A well-established bovine patella model of early joint degeneration was employed, in which micromechanical testing of fully hydrated osteochondral sections was carried out in conjunction with high-resolution imaging using differential interference contrast (DIC) optical light microscopy. A total of forty-two bovine patellae with different grades of tissue health ranging from healthy to mild, moderate, and severe cartilage degeneration, were selected. From the distal–lateral region of each patella, two adjacent osteochondral sections were obtained for the mechanical testing and the DIC imaging, respectively. Mechanical testing was carried out using a robotic micro-force acquisition system, applying compression tests over an array (area: 200 μm × 1000 μm, step size: 50 μm) across the osteochondral junction to obtain a stiffness map. Morphometric analysis was performed for the DIC images of fully hydrated cryo-sections. The levels of cartilage degeneration, DIC images, and the stiffness maps were used to associate the mechanical properties onto the specific tissue regions of cartilage, calcified cartilage, and subchondral bone plate. The results showed that there were up to 20% and 24% decreases (p < 0.05) in the stiffness of calcified cartilage and subchondral bone plate, respectively, in the severely degenerated group compared to the healthy group. Furthermore, there were increases (p < 0.05) in the number of tidemarks, bone spicules at the cement line, and the mean thickness of the subchondral bone plate with increasing levels of degeneration. The decreasing stiffness in the subchondral bone plate coupled with the presence of bone spicules may be indicative of a subchondral remodeling process involving new bone formation. Moreover, the mean thickness of the subchondral bone plate was found to be the strongest indicator of mechanical and associated structural changes in the osteochondral joint tissues.

(Less)
Please use this url to cite or link to this publication:
author
; ; ; and
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Bone formation, Calcified cartilage, Early degeneration, Subchondral bone plate, Tissue stiffness
in
Journal of the Mechanical Behavior of Biomedical Materials
volume
129
article number
105158
publisher
Elsevier
external identifiers
  • scopus:85125886321
  • pmid:35279448
ISSN
1751-6161
DOI
10.1016/j.jmbbm.2022.105158
language
English
LU publication?
no
additional info
Publisher Copyright: © 2022 The Authors
id
7fa28caf-81eb-4457-aba5-2fcfd8b634fb
date added to LUP
2025-11-17 10:53:19
date last changed
2025-12-29 14:40:45
@article{7fa28caf-81eb-4457-aba5-2fcfd8b634fb,
  abstract     = {{<p>The influence of joint degeneration on the biomechanical properties of calcified cartilage and subchondral bone plate at the osteochondral junction is relatively unknown. Common experimental difficulties include accessibility to and visualization of the osteochondral junction, application of mechanical testing at the appropriate length scale, and availability of tissue that provides a consistent range of degenerative changes. This study addresses these challenges. A well-established bovine patella model of early joint degeneration was employed, in which micromechanical testing of fully hydrated osteochondral sections was carried out in conjunction with high-resolution imaging using differential interference contrast (DIC) optical light microscopy. A total of forty-two bovine patellae with different grades of tissue health ranging from healthy to mild, moderate, and severe cartilage degeneration, were selected. From the distal–lateral region of each patella, two adjacent osteochondral sections were obtained for the mechanical testing and the DIC imaging, respectively. Mechanical testing was carried out using a robotic micro-force acquisition system, applying compression tests over an array (area: 200 μm × 1000 μm, step size: 50 μm) across the osteochondral junction to obtain a stiffness map. Morphometric analysis was performed for the DIC images of fully hydrated cryo-sections. The levels of cartilage degeneration, DIC images, and the stiffness maps were used to associate the mechanical properties onto the specific tissue regions of cartilage, calcified cartilage, and subchondral bone plate. The results showed that there were up to 20% and 24% decreases (p &lt; 0.05) in the stiffness of calcified cartilage and subchondral bone plate, respectively, in the severely degenerated group compared to the healthy group. Furthermore, there were increases (p &lt; 0.05) in the number of tidemarks, bone spicules at the cement line, and the mean thickness of the subchondral bone plate with increasing levels of degeneration. The decreasing stiffness in the subchondral bone plate coupled with the presence of bone spicules may be indicative of a subchondral remodeling process involving new bone formation. Moreover, the mean thickness of the subchondral bone plate was found to be the strongest indicator of mechanical and associated structural changes in the osteochondral joint tissues.</p>}},
  author       = {{Das Gupta, Shuvashis and Workman, Joshua and Finnilä, Mikko A.J. and Saarakkala, Simo and Thambyah, Ashvin}},
  issn         = {{1751-6161}},
  keywords     = {{Bone formation; Calcified cartilage; Early degeneration; Subchondral bone plate; Tissue stiffness}},
  language     = {{eng}},
  publisher    = {{Elsevier}},
  series       = {{Journal of the Mechanical Behavior of Biomedical Materials}},
  title        = {{Subchondral bone plate thickness is associated with micromechanical and microstructural changes in the bovine patella osteochondral junction with different levels of cartilage degeneration}},
  url          = {{http://dx.doi.org/10.1016/j.jmbbm.2022.105158}},
  doi          = {{10.1016/j.jmbbm.2022.105158}},
  volume       = {{129}},
  year         = {{2022}},
}