Purpose: Articular cartilage is an important load-bearing structure in synovial joint. Posttraumatic osteoarthritis may occur after cracking insult to cartilage, while not all insult to cartilage could progress into osteoarthritis. The initiating mechanism of osteoarthritis is still not well understood. Tensile stress is considered to have strong relationships with cartilage degradation. We hypothesize that cracks on articular cartilage under compression will induce tensile stress around the crack region, which may lead to chondrocytes change and cartilage degeneration.
Methods: In this study, using a 2D finite element model and animal validation study, the relationship between crack angle and local tensile stress was investigated.
Results: Under pure compressive load, 45 degrees oblique crack on cartilage could induce the highest peak tensile stress (3.9 times to compressive pressure) while no tensile stress was found in perpendicular crack cartilage. Animal study also confirmed finite element prediction that oblique crack may produce type I collagen around crack tip region.
Conclusions: This finding implies that crack angle could be an important factor contributing to initiate osteoarthritis after a traumatic injury. New strategies for prevention and early treatment of osteoarthritis might benefit from this study.
Jia Yu, Meng Zhang, Wen Zhang and Zong-Ping Luo
Journal of Bone Research and Reports received 235 citations as per google scholar report