A whole-joint, unidimensional, irreversible, and fine-grained MRI knee osteoarthritis severity score, based on cartilage, osteophytes and meniscus (OA-COM)

Objective To develop a whole-joint, unidimensional, irreversible, and fine-grained MRI knee osteoarthritis (OA) severity score, based on cartilage, osteophytes and meniscus (OA-COM), and to predict progression across different severity states using OA-COM as outcome and clinical variables as predictors. Methods Population-based knee pain cohort aged 40–79 was assessed at baseline and 7-year follow-up. OA-COM score was defined as the sum of MRI scores for cartilage, osteophytes and menisci, measured at 6, 8 and 6 sites, total score 0–54. To anchor severity levels, we fit cross-sectional logistic models using OA-COM to predict Kellgren-Lawrence (KL) grades in subsets at or one point below each grade. OA-COM threshold scores were selected on sensitivity, specificity, positive and negative predictive value. We developed longitudinal logistic models for OA-COM progression over each threshold over 7 years. Potential predictors included age, sex, BMI, malalignment, physical exam effusion, quadriceps weakness, and crepitus, selected on area under the receiver operating characteristic curve (AUC) and Akaike’s Information Criterion (AIC). Results Optimal OA-COM thresholds were 12, 18, 24 and 30, for KL grades 1 to 4. Significant predictors of progression (depending on threshold) included physical exam effusion, malalignment and female sex, with other selected predictors age, BMI and crepitus. Conclusion OA-COM (0–54 range) is a whole-joint, unidimensional, irreversible, and fine-grained MRI OA severity score reflecting cartilage, osteophytes and menisci. OA-COM scores 12, 18, 24 and 30 are equivalent to KL grades 1 to 4, while offering fine-grained differentiation of states between KL grades, and within pre-radiographic disease (KL = 0) or late-stage disease (KL = 4). In modeling, several clinical variables predicted progression across different states over 7 years.

Clinical relevance of MRI knee abnormalities in Australian rules football players: a longitudinal study

Background/AimThe clinical relevance of MRI knee abnormalities in athletes is unclear. This study aimed to determine the prevalence of MRI knee abnormalities in Australian Rules Football (ARF) players and describe their associations with pain, function, past and incident injury and surgery history.Methods75 male players (mean age 21, range 16–30) from the Tasmanian State Football League were examined early in the playing season (baseline). History of knee injury/surgery and knee pain and function were assessed. Players underwent MRI scans of both knees at baseline. Clinical measurements and MRI scans were repeated at the end of the season, and incident knee injuries during the season were recorded.ResultsMRI knee abnormalities were common at baseline (67% bone marrow lesions, 16% meniscal tear/extrusion, 43% cartilage defects, 67% effusion synovitis). Meniscal tears/extrusion and synovial fluid volume were positively associated with knee symptoms, but these associations were small in magnitude and did not persist after further accounting for injury history. Players with a history of injury were at a greater risk of having meniscal tears/extrusion, effusion synovitis and greater synovial fluid volume. In contrast, players with a history of surgery were at a greater risk of having cartilage defects and meniscal tears/extrusion. Incident injuries were significantly associated with worsening symptoms, BML development and incident meniscal damage.ConclusionsMRI abnormalities are common in ARF players, are linked to a previous knee injury and surgery history, as well as incident injury but do not dictate clinical symptomatology.

AB0779 CAN INFLAMMATION COEXIST IN PATIENTS WITH PROGRESSIVE PSEUDORHEUMATOID DYSPLASIA?

Background:Progressive pseudorheumatoid dysplasia(PPRD) is considered as a degenerative genetic bone disorder. It is caused by loss of function mutation in WNT-1 inducible signaling pathway protein-3(WISP-3)1. WISP-3 gene function is required for the normal function of cartilage and skeletal development. The patients are normal at birth and start developing symptoms around 3-6 years of age2. The disease is characterised by stiffness, pain, deformity due to enlargement of the ends of short and long bones. Often, such patients are misdiagnosed as Juvenile idiopathic arthritis(JIA). In general, PPRD being considered as non-inflammatory disease, immunosuppressants or disease modifying anti rheumatic drugs(DMARDS) like methotrexate treatment are not used for treatment.Objectives:We report a patient with characteristic findings of PPRD but with coexisting clinical and imaging evidence of inflammation.Methods:16 year old male boy born of third degree consanguineous asymptomatic parents presented with progressive swelling, deformity of bilateral small and large joints of upper and lower limbs. He also had pain in both hip and knee for past two years. Pain is associated with difficulty in walking and squatting. On examination he had bony enlargement around bilateral elbow, wrist, proximal and distal interphalangeal joints(Figure 1A). He also had restriction of bilateral hip movements and swelling of bilateral knee with effusion. He had exaggerated lumbar lordosis and flexion deformity of bilateral hip, knee. His blood counts, ESR, CRP were normal. Analysis of Knee joint synovial fluid showed cell count of 200/mm3 with no crystals and sterile culture. USG knee showed evidence of synovial thickening with increased power Doppler signals. Skeletal survey showed typical findings of PPRD with enlargement of epiphysis and osteoarthritis changes(Figure 1B). MRI hip showed minimal effusion, synovial thickening, edema with STIR hyperintensity and enlargement of bilateral femoral epiphysis. MRI knee showed minimal effusion, marrow edema in patella(Figure 1C, arrow head), femoral condyle, diffuse synovial thickening with contrast enhancement(Figure 1D, arrow) and deformed patellar contour. Immunological tests showed negative RF, ACPA and positive ANA(Hep2) speckled 4+. Immunoblot for ENA was negative. His ophthalmological evaluation showed no evidence of uveitis.Figure 1.Clinical picture showing typical hand deformity and swelling at bone ends(A), hand radiograph showing epiphyseal enlargement(B), MRI knee T2 STIR showing bone marrow edema(arrow head) in patella(C) and synovial thickening(arrow) with contrast enhancement in fat saturated T1 MRI with contrast.Results:Patient tested positive for homozygous mutation in WISP-3 gene. He was treated with ibuprofen and supportive measures. Orthopedic consultation obtained and planned for hip, knee replacement during follow up. Follow up imaging and acute phase response was advised after three months.Conclusion:Although PPRD was classically described as a degenerative disease, the findings presented in our case show coexisting inflammation. Bone marrow edema in weight bearing areas, synovial effusion may be explained as part of cartilage degeneration like in osteoarthritis but synovial hypertrophy with contrast enhancement, power Doppler signals in ultrasound, ANA positivity may be signs of coexisting inflammatory or autoimmune phenomenon.References:[1]Hurvitz JR, Suwairi WM et al. Mutations in the CCN gene family member WISP3 cause progressive pseudorheumatoid dysplasia. Nat Genet. 1999 Sep;23(1):94-8. doi: 10.1038/12699. PMID: 10471507.[2]Garcia Segarra N, Mittaz L et al. The diagnostic challenge of progressive pseudorheumatoid dysplasia (PPRD): a review of clinical features, radiographic features, and WISP3 mutations in 63 affected individuals. Am J Med Genet C Semin Med Genet. 2012 Aug 15;160C(3):217-29. doi: 10.1002/ajmg.c.31333. Epub 2012 Jul 12. PMID: 22791401.Disclosure of Interests:None declared

DIFFERENCE OF ANATOMY INFORMATION MRI KNEE JOINT ON VARIATION OF TIME REPETITION SEQUENCES STIR IN SAGITTAL SLICES

Background: Time Repetition (TR) is one of the main parameters of Inversion Recovery. The purpose of this study to determine differences in anatomical MRI information on the variation of the knee joint TR sequences STIR Sagittal slices. Method: Type of research is experimental. The study was conducted with MRI 1.5 Tesla. Data in the form of 42 image sequences STIR MRI knee joint with TR 3500, 4000, 4500, 5000, 5500, 6000, and 6500 ms. Anatomical assessments on the anterior cruciate ligament, posterior cruciate ligament, articular cartilage, and meniscus were performed by a radiologist. Data analyzed by Friedman and Wilcoxon test. Result: The results showed that there were differences in the MRI anatomical information of the knee joint of the STIR sagitas slice in the TR variation with p-value < 0.001. There is a difference in anatomical information between TR 5000 and 6000 ms (p-value = 0.034), TR 5000 and 6500 ms (p-value = 0.024), TR 5500 and 6500 ms (p-value = 0.038). There is no difference in anatomical information between TR 4500 and 5000 ms (p-value = 0.395), TR 4500 and 5500 ms (p-value = 0.131), TR 4500 and 6000 ms (p-value = 0.078), TR 4500 and 6500 ms (p-value = 0.066), TR 5000 and 5500 ms (p-value = 0.414), TR 5500 and 6000 ms (p-value = 0.102), TR 6000 and 6500 ms (p-value = 0.083). Conclusion: The optimal value to produce anatomical information of the knee joint sagittal MRI sequences STIR is TR 4500 ms.