Objective: To investigate the test-retest precision and to report the longitudinal change in cartilage thickness, the percentage of knees with progression and the predictive value of the machine... Show moreObjective: To investigate the test-retest precision and to report the longitudinal change in cartilage thickness, the percentage of knees with progression and the predictive value of the machine-learning-estimated structural progression score (s-score) for cartilage thickness loss in the IMI-APPROACH cohort - an exploratory, 5-center, 2-year prospective follow-up cohort. Design: Quantitative cartilage morphology at baseline and at least one follow-up visit was available for 270 of the 297 IMI-APPROACH participants (78% females, age: 66.4 +/- 7.1 years, body mass index (BMI): 28.1 +/- 5.3 kg/m(2), 55% with radiographic knee osteoarthritis (OA)) from 1.5T or 3T MRI. Test-retest precision (root mean square coefficient of variation) was assessed from 34 participants. To define progressor knees, smallest detectable change (SDC) thresholds were computed from 11 participants with longitudinal test-retest scans. Binary logistic regression was used to evaluate the odds of progression in femorotibial cartilage thickness (threshold: similar to 211 mu m) for the quartile with the highest vs the quartile with the lowest s-scores. Results: The test-retest precision was 69 mu m for the entire femorotibial joint. Over 24 months, mean cartilage thickness loss in the entire femorotibial joint reached -174 mu m (95% CI: [-207, -141] mu m, 32.7% with progression). The s-score was not associated with 24-month progression rates by MRI (OR: 1.30, 95% CI: [0.52, 3.28]). Conclusion: IMI-APPROACH successfully enrolled participants with substantial cartilage thickness loss, although the machine-learning-estimated s-score was not observed to be predictive of cartilage thickness loss. IMI-APPROACH data will be used in subsequent analyses to evaluate the impact of clinical, imaging, biomechanical and biochemical biomarkers on cartilage thickness loss and to refine the machine-learning-based s-score. (c) 2022 The Author(s). Published by Elsevier Ltd on behalf of Osteoarthritis Research Society International. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). Show less
Roemer, F.W.; Jansen, M.; Marijnissen, A.C.A.; Guermazi, A.; Heiss, R.; Maschek, S.; ... ; Wirth, W. 2022
Background: The IMI-APPROACH cohort is an exploratory, 5-centre, 2-year prospective follow-up study of knee osteoarthritis (OA). Aim was to describe baseline multi-tissue semiquantitative MRI... Show moreBackground: The IMI-APPROACH cohort is an exploratory, 5-centre, 2-year prospective follow-up study of knee osteoarthritis (OA). Aim was to describe baseline multi-tissue semiquantitative MRI evaluation of index knees and to describe change for different MRI features based on number of subregion-approaches and change in maximum grades over a 24-month period.Methods: MRIs were acquired using 1.5 T or 3 T MRI systems and assessed using the semi-quantitative MRI OA Knee Scoring (MOAKS) system. MRIs were read at baseline and 24-months for cartilage damage, bone marrow lesions (BML), osteophytes, meniscal damage and extrusion, and Hoffa- and effusion-synovitis. In descriptive fashion, the frequencies of MRI features at baseline and change in these imaging biomarkers over time are presented for the entire sample in a subregional and maximum score approach for most features. Differences between knees without and with structural radiographic (R) OA are analyzed in addition.Results: Two hundred eighty-nine participants had readable baseline MRI examinations. Mean age was 66.6 +/- 7.1 years and participants had a mean BMI of 28.1 +/- 5.3 kg/m(2). The majority (55.3%) of included knees had radiographic OA. Any change in total cartilage MOAKS score was observed in 53.1% considering full-grade changes only, and in 73.9% including full-grade and within-grade changes. Any medial cartilage progression was seen in 23.9% and any lateral progression on 22.1%. While for the medial and lateral compartments numbers of subregions with improvement and worsening of BMLs were very similar, for the PFJ more improvement was observed compared to worsening (15.5% vs. 9.0%). Including within grade changes, the number of knees showing BML worsening increased from 42.2% to 55.6%. While for some features 24-months change was rare, frequency of change was much more common in knees with vs. without ROA (e.g. worsening of total MOAKS score cartilage in 68.4% of ROA knees vs. 36.7% of no-ROA knees, and 60.7% vs. 21.8% for an increase in maximum BML score per knee).Conclusions: A wide range of MRI-detected structural pathologies was present in the IMI-APPROACH cohort. Baseline prevalence and change of features was substantially more common in the ROA subgroup compared to the knees without ROA. Show less
Although osteoarthritis is a common disease, there are currently no disease-modifying availible. For a long time osteoarthritis was considered a purely degenerative disease without inflammation of... Show moreAlthough osteoarthritis is a common disease, there are currently no disease-modifying availible. For a long time osteoarthritis was considered a purely degenerative disease without inflammation of the synovium (synovitis). However, recent research has shown that synovitis is of importance in patients with osteoarthritis. Therefore, this thesis aimed to understand the role synovitis in ossteoarthritis. In the first part of this thesis, we investigated the nature of synovitis by examining the synovium of osteoarthritis patients using differnt laboratory techniques. Furthermore, we validated a new synovitis scoring system on MRI with contrast. In the second part of this thesis, we investigated role of synovitis in relation to clinical characteristics such as pain and structural damage. This thesis shows that synovial inflammation in osteoarthritis is not only frequently present, but may also play a role in the pathophysiology of osteoarthritis and development of clinical features. Results presented in this thesis provide insight into different aspects of synovial inflammation aimed at increasing our understanding of the pathophysiology of OA and aiding to the development of disease-modifying drugs in OA. Show less
Osteoarthritis is a prevalent disease causing pain and disability. It__s aetiology is unknown and no curative treatment is available. Osteoarthritis research is complicated due to heterogeneity of... Show moreOsteoarthritis is a prevalent disease causing pain and disability. It__s aetiology is unknown and no curative treatment is available. Osteoarthritis research is complicated due to heterogeneity of the disease, slow progression and poor association of clinical features with radiographic abnormalities, imaging modality of choice until now. In this thesis the role of synovitis in osteoarthritis is studied in relationship with clinical features and structural damage. The studies described made especially use of data derived a prospective follow-up study in symptomatic hand osteoarthritis patients. Synovitis detected on ultrasound was associated with clinical features and with progression of structural damage after 2.3 years in hand osteoarthritis. In erosive osteoarthritis, a subtype of hand osteoarthritis, more synovitis was found in all hand joints, even in non-erosive joints, when compared to joints of patients without erosive osteoarthritis. Also, associations were found between synovitis and erosive development at follow-up. All analyses were performed on joint level, using GEE analyses, thereby taking into account patient effects. Associations were poor/absent when analyses were done on patient level. This is important for further research. These results indicate that synovitis plays a role in pain and in development of structural damage in osteoarthritis and could be a therapeutic target. Show less
