AB0713 MAGNETIC: RESONANCE IMAGING AND ULTRASONOGRAPHIC MEASUREMENTS OF THE FEMORAL CARTILAGE THICKNESS IN PATIENTS WITH ANKYLOSING SPONDYLITIS
Authors: Fatma Ali, Ayman Darwish, Shereen Refaat, Omnia Adel, Nadia El Ameen
Journal: Annals of the Rheumatic Diseases (2019)

<h3>Background:</h3> Ankylosing spondylitis (AS) is a progressive inflammatory disease involving cartilaginous structures in the spine and peripheral joints. <h3>Objectives:</h3> To examine the role of musculoskeletal ultrasound (MSUS) and magnetic resonance imaging (MRI) in assessing femoral cartilage thicknesses in patients with aS and healthy controls, and to study the correlation between femoral cartilage thicknesses measurements and disease parameters <h3>Methods:</h3> Twenty five patients with aS (17 males and 8 females), and twenty five age, sex and BMI matched healthy individuals were included. For all patients assessment of disease activity, spinal mobility, functional limitation and radiological changes were done. Thickness of the femoral articular cartilage was measured by MSUS using a 10-18 MHz linear probe, three mid-point measurements were taken from each knee at the lateral condyle, intercondylar area, and medial condyle. Thickness of the femorotibial articular cartilage was measured by MRI using 1.5 Tesla MR machine. <h3>Results:</h3> AS patients had thinner femoral cartilage thickness than the healthy controls at all MSUS measurement sites, with statistically significant differences at medial femoral condyle and intercondylar area in both right and left knees (p&lt;0.05). According to MRI examination, aS patients had statistically significant (p&lt;0.05) thinner cartilage thickness at all subdivisions of femoral and tibial condyles than the healthy controls. Femoral cartilage thickness measurements either assessed by MSUS or MRI was negatively correlated with age, age at onset of the disease, and measures of disease activity and radiological changes. Positive correlation between ultrasonographic total femoral cartilage thickness and MRI total femoral cartilage thickness was found (r=0.49, p=0.02). <h3>Conclusion:</h3> Patients with ankylosing spondylitis seem to have thinner femoral cartilage thickness than healthy controls. Correlations of knee cartilage thickness (assessed by MSUS and MRI) with demographic data and disease parameters reflect useful value of MSUS and MRI in determining early cartilage loss in aS patients. <h3>References</h3> [1] alDhaheri F, almteri T, Dwid N, Majdali a, Janoudi N and almoallim H(2017). Rituximab Can induce Remission in a Patient with ankylosing Spondylitis Who Failed anti-TNF-α agent. Am J Case Rep.; 18 :143-147. [2] amin S, LaValley MP, Guermazi a, Grigoryan M, Hunter DJ, Clancy M, et al (2005). The relationship between cartilage loss on magnetic resonance imaging and radiographic progression in men and women with knee osteoarthritis. Arthritis Rheum; 52: 3152-3159. [3] andriacchi TP and Favre J (2014). The nature of in vivo mechanical signals that influence cartilage health and progression to knee osteoarthritis.CurrRheumatol Rep.; 16(11) :463. [4] anwar F, a-Khayer a, Joseph G, Fraser MH, Jigajinni MV and allan DB (2011). Delayed presentation and diagnosis of cervical spine injuries in long-standing ankylosing spondylitis.Eur Spine J.; 20(3) :403-7. <h3>Disclosure of interests:</h3> None declared