Background Conventional radiography is the simplest and least expensive imaging method for assessing osteoarthritis (OA)of the knee. However, it allows an indirect estimation of cartilage thickness and integrity of the meniscus. Hence the value of modern imaging (ultrasound and MRI) in the diagnosis and the monitoring of this pathology.
Objectives To assess the correlation between Kellgren & Lawrence (KL) gradings and MRI findings in particular: cartilage defects, bone marrow lesions (BMLS) and meniscal lesions in knee OA patients.
Methods This is a cross-sectional study including patients with primary knee OA. Demographics, clinical and laboratory characteristics for the disease were collected. Radiographs of the knee were evaluated by Kellgren & Lawrence gradings. All patients underwent magnetic resonance imaging (MRI) of the dominant knee. The results were interpreted according to WORMS system  (Whole organ magnetic resonance imaging score) that takes into account 14 regions divised into 04 compartments: medial femoral tibial joint (MFTJ) lateral femoral tibial (LFTJ), femoral patellar (PFJ) and the S region (inter thorny).
Results Twenty patients with osteoarthritis of the knee were included in the study, 85% were female. The mean age was 59.3±10.3 years. The patients had a mean body mass index 30.1±4.7 kg/ m2. The functional discomfort of patients assessed by the WOMAC averaged 38.3±11.3. We found a positive correlation between the Kellgren & Lawrence and MRI data: cartilage defects (r=0.50) and BMLS (r=0,68) and meniscal lesions (r=0.18), statistically significant only for BMLs. Adjusting for age, gender and BMI did not alter these associations.
Conclusions This study suggests the existence of a correlation between MRI findings and standard radiography in knee OA. Thus, radiography remains useful in daily practice for the diagnosis and assesses the severity of knee osteoarthritis. Further studies are needed to confirm these results.
OsteoArthritis and Cartilage (2004) 12, 177–190
Disclosure of Interest None declared