Direct Comparison of Fixed Flexion Radiography and MRI in Knee Osteoarthritis: Responsiveness Data from the Osteoarthritis Initiative.
ABSTRACT OBJECTIVE: Minimum radiographic joint space width (mJSW) represents the FDA standard for demonstrating structural therapeutic benefits for knee osteoarthritis (KOA), but only shows moderate responsiveness (sensitivity to change). We directly compare the responsiveness of MRI-based cartilage thickness and JSW measures from fixed-flexion radiography (FFR) and explore the correlation of region-matched changes between both methods. METHODS: 967 knees of Osteoarthritis Initiative participants with radiographic KOA were studied: 445 over one year with coronal FLASH MRI and FFR, and 375/522 over one /two years with sagittal DESS MRI and FFR. Standardized response means (SRM) of cartilage thickness and mJSW were compared using the sign-test. RESULTS: With FLASH MRI, SRM was -0.28 for medial compartment (MFTC) cartilage loss vs. -0.15 for mJSW, and -0.32 vs. -0.22 for the most sensitive MRI subregion (central MFTC) vs. the most sensitive fixed location JSW(X=0.25) . With DESS MRI, one-year SRM was -0.34 for MFTC vs. -0.22 for mJSW and -0.44 vs. -0.28 for central MFTC vs. JSW(X=0.225). Over two years, the SRM was significantly greater for MFTC than for mJSW (-0.43 vs. -0.31, p=0.017) and for central MFTC than for JSW(X=0.225) (-0.51 vs. -0.44, p<0.001). Correlations between changes in spatially matched MRI subregions and fixed location JSW were not consistently higher (r=0.10-0.51) than those between non-matched locations (r=0.15-0.50). CONCLUSIONS: MRI displays greater responsiveness in KOA than JSW FFR-based JSW, with the greatest SRM observed in the central medial femorotibial compartment. Fixed-location radiographic measures appear not capable of determining the spatial distribution of femorotibial cartilage loss.
SourceAvailable from: Colin Miller[Show abstract] [Hide abstract]
ABSTRACT: Imaging in clinical trials is used to evaluate subject eligibility, and/or efficacy of intervention, supporting decision making in drug development by ascertaining treatment effects on joint structure. This review focusses on imaging of bone and cartilage in clinical trials of (knee) osteoarthritis. We narratively review the full-text literature on imaging of bone and cartilage, adding primary experience in the implementation of imaging methods in clinical trials. Aims and constraints of applying imaging in clinical trials are outlined. The specific uses of semi-quantitative and quantitative imaging biomarkers of bone and cartilage in osteoarthritis trials are summarized, focusing on radiography and magnetic resonance imaging (MRI). Studies having compared both imaging methodologies directly and those having established a relationship between imaging biomarkers and clinical outcomes are highlighted. To make this review of practical use, recommendations are provided as to which imaging protocols are ideal for capturing specific aspects of bone and cartilage tissue, and pitfalls in their usage are highlighted. Further, the longitudinal sensitivity to change, of different imaging methods is reported for various patient strata. From these power calculations can be accomplished, provided the strength of the treatment effect is known. In conclusion, current imaging methodologies provide powerful tools for scoring and measuring morphological and compositional aspects of most articular tissues, capturing longitudinal change with reasonable to excellent sensitivity. When employed properly, imaging has tremendous potential for ascertaining treatment effects on various joint structures, potentially over shorter time scales than required for demonstrating effects on clinical outcomes.Osteoarthritis and Cartilage 10/2014; 22(10):1516-1532. DOI:10.1016/j.joca.2014.06.023 · 4.66 Impact Factor
Article: Imaging following acute knee trauma[Show abstract] [Hide abstract]
ABSTRACT: Joint injury has been recognized as a potent risk factor for the onset of osteoarthritis. The vast majority of studies using imaging technology for longitudinal assessment of patients following joint injury have focused on the injured knee joint, specifically in patients with anterior cruciate ligament injury and meniscus tears where a high risk for rapid onset of post-traumatic osteoarthritis is well known. Although there are many imaging modalities under constant development, magnetic resonance (MR) imaging is the most important instrument for longitudinal monitoring after joint injury. MR imaging is sensitive for detecting early cartilage degeneration and can evaluate other joint structures including the menisci, bone marrow, tendons, and ligaments which can be sources of pain following acute injury. In this review, focusing on imaging following acute knee trauma, several studies were identified with promising short-term results of osseous and soft tissue changes after joint injury. However, studies connecting these promising short-term results to the development of osteoarthritis were limited which is likely due to the long follow-up periods needed to document the radiographic and clinical onset of the disease. Thus, it is recommended that additional high quality longitudinal studies with extended follow-up periods be performed to further investigate the long-term consequences of the early osseous and soft tissue changes identified on MR imaging after acute knee trauma.Osteoarthritis and Cartilage 10/2014; 22(10):1429-1443. DOI:10.1016/j.joca.2014.06.024 · 4.66 Impact Factor
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ABSTRACT: To identify risk factors for radiographic signs of post-traumatic OA 2-3 years after ACL reconstruction through multivariable analysis of minimum joint space width (mJSW) differences in a specially designed nested cohort. A nested cohort within the Multicenter Orthopaedic Outcomes Network cohort included 262 patients (148 females, average age 20) injured in sport who underwent ACL reconstruction in a previously uninjured knee, were 35 or younger, and did not have ACL revision or contralateral knee surgery. mJSW on semi-flexed radiographs was measured in the medial compartment using a validated computerized method. A multivariable generalized linear model was constructed to assess mJSW difference between the ACL reconstructed and contralateral control knees while adjusting for potential confounding factors. Unexpectedly, we found the mean mJSW was 0.35 mm wider in ACL reconstructed than in control knees (5.06 mm (95% CI 4.96 - 5.15 mm) versus 4.71 mm (95% CI 4.62 - 4.80 mm), p<0.001). However, ACL reconstructed knees with meniscectomy had narrower mJSW compared to contralateral normal knees by 0.64 mm (95% C.I. 0.38 - 0.90 mm) (p<0.001). Age (p<0.001) and meniscus repair (p=0.001) were also significantly associated with mJSW difference. Semi-flexed radiographs can detect differences in mJSW between ACL reconstructed and contralateral normal knees 2-3 years following ACL reconstruction, and the unexpected wider mJSW in ACL reconstructed knees may represent the earliest manifestation of post-traumatic osteoarthritis and warrants further study. Copyright © 2014. Published by Elsevier Ltd.Osteoarthritis and Cartilage 01/2015; DOI:10.1016/j.joca.2014.12.018 · 4.66 Impact Factor