title: Damage and degenerative changes in menisci-covered and exposed tibial osteochondral regions after simulated landing impact compression-a porcine study.
abstract: The capacity of menisci-covered and exposed tibial osteochondral regions in resisting impact-induced damage and degeneration is not fully understood. This study sought to evaluate damage and degenerative changes in these regions upon a single simulated landing impact. We hypothesized that the menisci-covered regions are more susceptible to damage and degeneration than their exposed counterparts. Menisci-covered and exposed tibial osteochondral explants were extracted from fresh porcine hind legs and placed in culture up to 14 days. Impact compression, based on a single 10-Hz haversine, was performed at Day 1. Control (non-impact) and impacted explants were randomly selected for cell viability assessment, glycoaminoglycan and collagen content assays, histology, immunohistochemistry, and micro-computed tomography. When subjected to 2-mm displacement compression, exposed explants achieved a significantly higher peak impact stress (p < 0.05) than menisci-covered explants. No significant difference in cell viability, glycoaminoglycan and collagen content, and Mankin scores (p > 0.05) was observed between both explant groups. Both groups were observed with reduced proteoglycan and type II collagen staining at Day 14; the exposed group was noted with increased cartilage volume at Days 7-14. The inferior resistance of menisci-covered regions, against impact-induced damage and degeneration, is a potential factor that may contribute to the meniscectomy model of osteoarthritis.
authors.affiliation: Department of Orthopaedic Surgery, NUS Tissue Engineering Programme, Office of Life Sciences, National University of Singapore, 27 Medical Drive, Singapore 117510, Singapore.
authors.forename: Chen Hua
authors.initials: CH
authors.lastname: Yeow
authors.forename: Swee Ting
authors.initials: ST
authors.lastname: Lau
authors.forename: Peter Vee Sin
authors.initials: PV
authors.lastname: Lee
authors.forename: James Cho Hong
authors.initials: JC
authors.lastname: Goh
mesh_terms: D000818:Animals; D002356:Cartilage / Q000293:injuries*; D002358:Cartilage, Articular / Q000473:pathology*; D002470:Cell Survival; D019902:Chondrocytes / Q000166:cytology; D003094:Collagen / Q000378:metabolism; D006025:Glycosaminoglycans / Q000378:metabolism; D007718:Knee Injuries / Q000473:pathology*; D008592:Menisci, Tibial / Q000473:pathology* / Q000648:ultrastructure; D010003:Osteoarthritis / Q000473:pathology; D020370:Osteoarthritis, Knee / Q000473:pathology; D034421:Sus scrofa
chemical_list: D006025:Glycosaminoglycans; D003094:Collagen