Changes in MR relaxation times of the meniscus with acute loading: An in vivo pilot study in knee osteoarthritis

摘要: THE MENISCUS, A fibrocartilaginous tissue found within the knee joint, is responsible for joint congruity, shock dissipation, load transmission, lubrication, and stability of (1,2). The mechanical function meniscus largely depends on structural molecular integrity its matrix, composed a network collagen fibers (type I smaller amounts type II) immobilizing proteoglycans (PG) (2,3). While PGs in healthy resist large loads, it fibrils arranged fibrous lamellae that make efficient absorbers (4). Because these functional roles, damage to or loss menisci affects articular cartilage, as shown by increased risk developing osteoarthritis (OA) after meniscectomy (5). Traditionally, cartilage considered an initiator OA, but changes meniscus, which plays critical role normal biomechanics may be precursor OA. Studies have also demonstrated meniscal pathologies, such degeneration tears (6–8), are associated with change extracellular matrix (ECM) patients early late stages OA (9,10). increasingly being recognized important (1–5). Morphological defects visualized MRI preceded their ECM (8,10,11). In stage osteoarthritis, exhibits proteoglycan content, collagens, less organized fiber networks than those (12–18), swelling, resulting properties. Changes key finding evolution they likely alter distribution transmitted underlying cartilage. Thus, quantitative measures detect monitor occur both unloaded loaded conditions, could provide powerful diagnostic measurements early-stage OA. Recent studies potential MR relaxation times (T1ρ T2) studying biochemical composition meniscus. This technology promising quantifying injury (15,19). These highly sensitive alterations vivo (20–22). Previous content orientation major factor T2 (21,22). time mapping wide range water interactions particular anisotropy therefore play assessing degeneration. exact contributor T1ρ remain disputed generally agreed upon metrics macromolecular structure integrity. Rauscher et al reported results using this technique quantify degenerative subjects (15). several investigated use effect acute loading physical exercise (23–27), there lack information regarding times. Understanding behavior valuable transmission forces persons OA. Thus purpose study was evaluate body osteoarthritic knees compare findings age-matched controls. hypothesis will exhibit greater when compared knees.