AB0980 Factors associated with loss of cartilage in knee osteoarthritis
Authors: V. Vardanyan, V. Mukuchyan, A. Kirakosyan
Journal: Annals of the Rheumatic Diseases (2018)

<h3>Background</h3> Osteoarthritis (OA) is one of the leading causes of pain and disability worldwide. The structural changes in knee OA are characterised mainly by the progressive loss of cartilage, which is associated with additional structural changes such as subchondral bone lesions and alterations in the menisci. Unfortunately, these changes cannot be effectively treated conservatively. Further determination of modifiable risk factors of cartilage loss is extremely important for improvement of OA management. <h3>Objectives</h3> The main objective of the study was the determination of factors associated with loss of cartilage in knee OA. <h3>Methods</h3> 294 patients (277 female, 17 male, mean age 55, 09±8,56 years) with newly diagnosed mild to moderate primary knee osteoarthritis were investigated. X-ray and ultrasound examinations of knee joints were performed. The thickness of cartilage and synovial layer, as well as presence of synovitis, tendinitis, osteophytes, Baker's cysts, tear of meniscus were determined. For determination of factors associated with loss of cartilage both univariate and multivariate analyses were performed. The data is introduced as odds ratios (OR) with 95% confidence interval (CI). The results were considered significant when p &lt;0.05. <h3>Results</h3> Expressed thinning of cartilage (≤2 mm) was observed in 216 (73,5%) patients, abnormal thickening of synovial layer (≥3 mm) – in 76 (25,9%), synovitis – in 88 (29,9%), tendinitis – in 38 (12,9%), osteophytes – in 273 (92,9%), Baker's cysts –in 93 (31,6%), tears of meniscus – in 93 (31,6%) patients. Univariate analysis had shown that loss of cartilage (≤2 mm) was significantly (p&lt;0,05) associated with age &gt;55 (OR/95% CI/=2,0/1,3–3,4/, p&lt;0,05), thickening of synovial layer (OR/95% CI/=2,9/1,5–6,2/, p&lt;0,01), synovitis (OR/95% CI/=2,6/1,3–5,0/, p&lt;0,01) and osteophytes (OR/95% CI/=14,8/4,8–45,5/, p&lt;0,01). Following factors were then stepwise included in the model of multivariate logistic regression: age &gt;55, thickening of synovial layer and osteophytosis. According to results of analysis, age &gt;55 had lost its significance, was evaluated as confounding factor (OR/95% CI/=1,2/0,7–2,2/, p=0,4) and excluded from the model. Finally, loss of cartilage (thickness ≤2 mm) was found to be significantly and independently associated with abnormal thickening of synovial layer (OR/95% CI/=2,8/1,3–6,0/, p&lt;0,05) and osteophytosis (OR/95% CI/=12,8/3,9–41,6/, p&lt;0,01). <h3>Conclusions</h3> A positive association of cartilage loss with abnormal thickening of synovial layer (with further development of synovitis) and presence of osteophytes was determined. While cartilage loss and meniscal damage are not yet clearly treatable, treatments targeting inflammation within the joint are available. Thereby, forehanded treatment of secondary inflammatory conditions of joint, as well as strategies, directed toward dissection of osteophytes, can decrease cartilage loss and structural damage in OA. <h3>References</h3> [1] Martel-Pelletier J, Lajeunesse D, Pelletier JP: Etiopathogenesis of osteoarthritis. Arthritis and Allied Conditions: A Textbook of Rheumatology. Edited by: Koopman WJ, Moreland LW. 2005, Baltimore, MD: Lippincott, Williams &amp; Wilkins, 2199–2226. <h3>Disclosure of Interest</h3> None declared