BackgroundThe aim of this study was to identify a primate model of degenerative knee osteoarthritis (KOA) that may be more relevant for research studies on degenerative KOA in humans.Material/MethodsSixteen specific-pathogen-free (SPF) male cynomolgus monkeys (Macaca fascicularis) were divided into group A (n=8), an old group (22.0–25.3 years of age), and group B (n=8), a young group (3.0–5.2 years of age). For each primate, the behavior was observed, knee circumference was measured, knee joint X-rays were performed, and peripheral blood white blood cell (WBC) counts were measured, and the Kellgren and Lawrence (K-L) system was used for the classification of osteoarthritis. An enzyme-linked immunoassay (ELISA) was performed on knee joint fluid to measure levels of interleukin (IL)-1β, transforming growth factor (TGF)-β1, and matrix metalloproteinase (MMP)13. Changes in articular cartilage were evaluated using the Brittberg score and the Mankin histopathology grading score, respectively. Quantitative reverse transcription polymerase chain reaction (RT-qPCR) and Western blot were used to measure the expression of the NOTCH3, JAG1, and ACAN genes in knee cartilage specimens, and the findings in the two groups of primates were compared.ResultsSeven old aged primates in group A were compared with group B, and showed significant differences in WBC count, synovial fluid IL-1β, TGF-β1, and MMP13 levels, expression levels of the NOTCH3, JAG1, and ACAN genes in knee cartilage specimens, and in the Brittberg and Mankin scores (all, P<0.05).ConclusionsCynomolgus monkeys (Macaca fascicularis) might be a model for age-related degenerative KOA.
Background: Split fractures of the humeral greater tuberosity (HGT) are common injuries. Although there are numerous surgical treatments for these fractures, no classification system combining clinical and biomechanical characteristics has been presented to guide the choice of fixation method.Methods: We created a standardised fracture of the HGT in 24 formalin-fixed cadavers. Six were left as single-fragment fractures (Group A), six were further prepared to create single-fragment with medium size full-thickness rotator cuff tear (FT-RCTs) fractures (Group B), six were cut to create multi-fragment fractures (Group C), and six were cut to create multi-fragment with FT-RCT fractures (Group D). Each specimen was fixed with a shortened proximal humeral internal locking system (PHILOS) plate. The fixed fractures were subjected to load and load-to-failure tests and the differences between groups analysed.Results: The mean load-to-failure values were significantly different between groups (Group A, 446.83 ± 38.98 N; Group B, 384.17 ± 36.15 N; Group C, 317.17 ± 23.32 N and Group D, 266.83 ± 37.65 N, P < 0.05). The load-to-failure values for fractures with a greater tuberosity displacement of 10 mm were significantly different between each group (Group A, 194.00 ± 29.23 N; Group B, 157.00 ± 29.97 N; Group C, 109.00 ± 17.64 N and Group D, 79.67.83 ± 15.50 N; P < 0.05). These findings indicates that fractures with a displacement of 10 mm have different characteristics and should be considered separately from other HGT fractures when deciding surgical treatment.Conclusions: Biomechanical classification of split fractures of the HGT is a reliable method of categorising these fractures in order to decide surgical treatment. Our findings and proposed system will be a useful to guide the choice of surgical technique for the treatment of fractures of the HGT.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.