Hostname: page-component-77c89778f8-m8s7h Total loading time: 0 Render date: 2024-07-22T23:26:43.911Z Has data issue: false hasContentIssue false

Zone-Specific Changes in Micromechanical, Biochemical, and Structural Properties in Articular Cartilage from a Rabbit Joint Flexion Model

Published online by Cambridge University Press:  01 February 2011

Cheng Li
Affiliation:
cli@newton.berkeley.edu, University of California, Berkeley, UC Berkeley & UCSF Joint Graduate Group in Bioengineering, 2121 Etcheverry Hall, Dept. of Mechanical Engineering, University of California, Berkeley, Berkeley, CA, 94720, United States, 510-643-9095
Karen B. King
Affiliation:
karen.king@uchsc.edu, University of Colorado at Denver and Health Sciences Center, Department of Orthopaedics - Bioengineering, 12800 E. 19th Ave. RC1 N Room 2103, Mailstop 8343 PO Box 6511, Aurora, CO, 80045, United States
Lisa A. Pruitt
Affiliation:
lpruittt@me.berkeley.edu, University of California, Berkeley, Mechanical Engineering, 5134 Etcheverry Hall, Mailstop 1740, Berkeley, CA, 94720-1740, United States
Get access

Abstract

Metacarpophalangeal (MCP) joint proximal bone-cartilage specimens from the fourth digit were collected from repetitively flexed and non-flexed (control) paws of four New Zealand White rabbits. The specimens were cryo-fractured to reveal a sagittal cut containing the cartilage zones of different collagen microstructure. Nanoindentation, Fourier Transform infrared microspectroscopic imaging (FTIRMI), and histology were performed on a region of interest (ROI) ∼400 microns wide and through the thickness of the cartilage with two goals in mind: (1) to examine the effect of collagen network structure (random in the mid zone versus organized in the deep zone) on the biomechanical and biochemical properties of cartilage; and (2) to understand the changes in these properties due to physical forces. We found that zone microstructure significantly affected the measurement of the local relaxed modulus measured by nanoindentation. The deep zone had a higher modulus than the mid zone (Wilcoxon paired test, p<0.05). We also found that flexion significantly decreased the proteoglycan content in both the mid and deep zones (Wilcoxon paired test, p<0.05), suggesting indirect repetitive loading in the rabbit paw can be damaging to the joint via down regulating proteoglycan synthesis in the mid and deep zone cartilage. This is the first study to simultaneously report the local zone-specific mechanical and biochemical properties in the rabbit joint flexion model.

Type
Research Article
Copyright
Copyright © Materials Research Society 2008

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1 King, K. B., Opel, C. F. and Rempel, D. M., “Cyclical articular joint loading leads to cartilage thinning and osteopontin production in a novel in vivo rabbit model of repetitive finger flexion,” Osteoarthritis Cartilage 13 (11), 971978 (2005). Begin typing text here.Google Scholar
2 Li, C., Pruitt, L. A. and King, K. B., “Nanoindentation differentiates tissue-scale functional properties of native articular cartilage,” J.Biomed.Mater.Res.A. 78 (4), 729738 (2006)Google Scholar
3 Camacho, N. P. et al., “FTIR microscopic imaging of collagen and proteoglycan in bovine cartilage,” Biopolymers 62 (1), 18 (2001).Google Scholar
4 Gwynn, I. ap et al., “Novel aspects to the structure of rabbit articular cartilage,” Eur.Cell.Mater. 4, 1829 (2002).Google Scholar
5 Saadat, E. et al., “Long-term cyclical in vivo loading increases cartilage proteoglycan content in a spatially specific manner: an infrared microspectroscopic imaging and polarized light microscopy study,” Arthritis Res.Ther. 8 (5), R147 (2006).Google Scholar
6 Saadat, E. et al., “The effect of frequency and force of in vivo loading of proteoglycan content of rabbit articular cartilage,” Transactions of the 54th Annual Meeting of the Orthopaedic Research Society, (2008).Google Scholar