Similarities and discrepancies in subchondral bone structure in two differently induced canine models of osteoarthritis.
In osteoarthritis (OA), cartilage degradation is accompanied by subchondral bone changes. The pathogenesis and physiology of bone changes in OA are still unclear. The changes in subchondral bone architecture and cartilage damage were compared in differently induced experimental models of OA. Experimental OA was induced bilaterally by anterior cruciate ligament transection (ACLT) or by cartilage trauma (Groove model); bilateral sham surgery served as control. Lysylpyridinoline (LP, bone resorption) and C-telopeptide of type II collagen (CTX-II, cartilage breakdown) were measured over time. At 20 weeks after surgery, the subchondral cortical plate and trabecular bone of the tibia were analyzed by micro-computed tomography (microCT) and cartilage degeneration was analyzed histologically and biochemically. In both models, cartilage degeneration and cortical subchondral plate thinning were present. CTX-II levels were elevated over time in both models. Subchondral trabecular bone changes were observed only in the ACLT model, not in the Groove model. Correspondingly, LP levels were elevated over time in the ACLT model and not in the Groove model. Interestingly, the trabecular bone changes in the ACLT model were extended to the metaphyseal area. The early decrease in plate thickness, present in both models, as was cartilage damage, suggests that plate thinning is a phenomenon that is intrinsic to the process of OA independent of the cause/induction of OA. On the other hand, trabecular changes in subchondral and metaphyseal bone are not part of a common pathway of OA development and may be induced biomechanically in the destabilized and less loaded ACLT joint.
Intema
Femke
F
Department of Rheumatology and Clinical Immunology, University Medical Center Utrecht, Utrecht, The Netherlands.
Sniekers
Yvonne H
YH
Weinans
Harrie
H
Vianen
Marieke E
ME
Yocum
Sue A
SA
Zuurmond
Anne-Marie M
AM
DeGroot
Jeroen
J
Lafeber
Floris P
FP
Mastbergen
Simon C
SC
D000596:Amino Acids / Q000378:metabolism; D000818:Animals; D016118:Anterior Cruciate Ligament / Q000601:surgery; D001842:Bone and Bones / Q000473:pathology*; D002356:Cartilage / Q000293:injuries / Q000378:metabolism; D024042:Collagen Type I / Q000378:metabolism; D004195:Disease Models, Animal; D004285:Dogs; D005260:Female; D006132:Growth Plate / Q000473:pathology; D010003:Osteoarthritis / Q000473:pathology*; D010455:Peptides / Q000378:metabolism; D000072042:Salter-Harris Fractures; D013977:Tibia / Q000473:pathology; D055114:X-Ray Microtomography
D000596:Amino Acids; D024042:Collagen Type I; D010455:Peptides; C052929:collagen type I trimeric cross-linked peptide; C036020:deoxypyridinoline