Purpose: Early-stage osteoarthritis (OA) includes glycosaminoglycan (GAG) loss and collagen disruption that cannot be seen on morphological magnetic resonance imaging (MRI). T1ρ MRI is a measurement that probes the low-frequency rate of exchange between protons of free water and those from water associated with macromolecules in the cartilage's extracellular matrix. While it has been hypothesized that increased water mobility resulting from early osteoarthritic changes cause elevated T1ρ MRI values, there remain several unknown mechanisms influencing T1ρ measurements in cartilage. The purpose of this work was to relate histological and biochemical metrics directly measured from osteochondral biopsies and fluid specimens with quantitative MRI-detected changes of in vivo cartilage composition.
Patients And Methods: Six young patients were enrolled an average of 41 days after acute anterior cruciate ligament (ACL) rupture. Femoral trochlear groove osteochondral biopsies, serum, and synovial fluid were harvested during ACL reconstruction to complement a presurgery quantitative MRI study (T1ρ, T2, delayed gadolinium-enhanced MRI of cartilage [dGEMRIC] relaxation times). A high-resolution MRI scan of the excised osteochondral biopsy was also collected. Analyses of in vivo T1ρ images were compared with ex vivo T1ρ imaging, GAG assays and histological GAG distribution in the osteochondral biopsies, and direct measures of bone and cartilage turnover markers and "OA marker" 3B3 in serum and synovial fluid samples.
Conclusion: T1ρ relaxation times in patients with a torn ACL were elevated from normal, indicating changes consistent with general fluid effusion after blunt joint trauma. Increased chondrogenic progenitor cell (CPC) production of chondroprotective lubricin may relate to cartilage surface disruption by blunt trauma and CPC amplification of joint inflammation. Disparity between ex vivo and matched in vivo MRI of trochlear cartilage suggests MRI signal differences that may be related to the synovial fluid environment. T1ρ is emerging as a promising MRI biomarker to relate noninvasive measures of whole-joint condition and cartilage composition to direct measures of cartilage changes in the acute phase of joint injuries.
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http://dx.doi.org/10.2147/ORR.S43973 | DOI Listing |
Osteoarthr Cartil Open
March 2025
Pain Centre Versus Arthritis and Academic Unit of Injury, Recovery and Inflammation Sciences, University of Nottingham, UK.
Objectives: Histological osteochondral characteristics of inflammation, fibrosis, vascularity, cartilage islands, vessels entering cartilage, thickened trabeculae and cysts are associated with bone marrow lesions (BMLs) in human knee osteoarthritis (OA). We identified and developed a method for scoring comparable pathology in two rat OA knee pain models.
Methods: Rats (n = 8-10 per group) were injected with monoiodoacetate (MIA) or saline, or underwent meniscal transection (MNX) or sham surgery.
Proc (Bayl Univ Med Cent)
September 2024
Texas A&M University, Temple, Texas, USA.
A 13-year-old boy was referred to orthopedic surgery for chronic intermittent pain and swelling of the left knee. Initial imaging was consistent with osteochondritis dissecans of the femoral condyle. Follow-up imaging demonstrated unexpected progression, with a mass extending into the notch, replacing the anterior cruciate ligament, and eroding the femoral and tibial condyles.
View Article and Find Full Text PDFRadiology
December 2024
From the Department of Radiology, Hanyang University Hospital, 222-1 Wangsimni-ro, Seongdong-gu, Seoul 04763, South Korea (Sunmin Lee, Y.J.K., Seunghun Lee); Department of Radiology, Hanyang University Guri Hospital, Guri, South Korea (J.R.); Department of Radiology, Eunpyeong St Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, South Korea (H.Y.L.); Department of Radiology, University of California, Davis, Sacramento, Calif (H.J.); Biostatistics Laboratory, Medical Research Collaborating Center, Industry-University Cooperation Foundation, Hanyang University, Seoul, South Korea (H.W.T., J.K.); and Department of Pre-Medicine, College of Medicine, Hanyang University, Seoul, South Korea (J.K.).
Background The calcified cartilage layer and subchondral bone plate (SBP) contribute to osteoarthritis development. Three-dimensional (3D) ultrashort echo-time (UTE) MRI can help to evaluate calcified cartilage and SBP in various stages of cartilage degradation. Purpose To compare calcified cartilage and SBP abnormalities using 3D UTE MRI with cartilage degradation and osteochondral junction (OCJ) abnormalities observed at proton-density fast spin-echo with fat suppression (PDFS) MRI.
View Article and Find Full Text PDFCryobiology
December 2024
Department of Surgery, University of Alberta, Edmonton, Alberta, Canada. Electronic address:
Successful cryopreservation of articular cartilage (AC) depends on a number of variables, including heat transfer, sample packaging for cryogenic storage, cryoprotectant agent (CPA) concentration (toxicity), and CPA permeation into AC. In the first experiment of the present study, we used a combination of our established vitrification protocol (430-min multi-step loading Protocol 8) and the metal Ovarian Tissue Cryosystem (OTC) as a closed vitrification-storage-rewarming container to vitrify 7-mm diameter porcine osteochondral dowels with 2 methods of storage (storage in the OTC with or without a surrounding vitrification solution). In the second experiment, in an attempt to introduce a more reproducible and safe vitrification protocol, we employed our successful Protocol 8 with the OTC as the CPA loading container and a cryobag as the storage container (with or without surrounding vitrification solution).
View Article and Find Full Text PDFSci Rep
November 2024
Paris Cité University CNRS INSERM, B3OA, UMR 7052, U 1271, 10 avenue de Verdun, Paris, 75010, France.
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