Background Osteoncrosis (ON) is reputed to be one of the most disabling complications following Corticosteroid(CS) medication. However, evidence regarding risk of asymptomatic prevalence among different diseases and the impact of variable steroid regimens are conflicting.

Objectives We aimed to determine the prevalence of ON of femoral head in asymptomatic patients with systemic rheumatic diseases who received high-dose CS and also clarify its relationship with different dosages and regimens.

Methods Fifty consecutive patients receiving high dose CS for rheumatic diseases who have no pelvic pain were included to this study. MRI of both hips was performed on all patients using a 1.5 Tesla to diagnose ON.

Results Among 50 study subjects, 18 (36%) developed ON of the femoral head. The groups with and without ON were comparable in terms of sex, age and mean starting CS dose. There was no statistical difference in the type of CS regimen including daily dose, peak dose and cumulative dose between the ON and non ON groups. However, both the cumulative CS dose and the duration of time in which high dose CS (equivalent to 30mg prednisolone or more) was given were associated with the prevalence of silent ON

Conclusions According to high prevalence of 0N in our selected patients with no other identifiable risk factor for ON, monitoring of high risk patients with periodic hip MRI would have diagnose necrosis in early stage.

References Felson DT, Anderson JJ. Across-study evaluation of association between steroid dose and bolus steroids and avascular necrosis of bone. (1987) Lancet. Apr 18;1(8538):902-6. Colwell CW Jr, Robinson CA, Stevenson DD, et al. Osteonecrosis of the femoral head in patients with inflammatory arthritis or asthma receiving corticosteroid therapy.(1996) Orthopedics. Nov;19(11):941-6. Kale N, Agaoglu J, Tanik O. Correlation of cumulative corticosteroid treatment with magnetic resonance imaging assessment of avascular femoral head necrosis in patients with multiple sclerosis. (2010) Neurol Int. November 26; 2(2): e17.

Acknowledgements The authors would like to acknowledge Deputy of research in Tehran University of Medical Sciences

Disclosure of Interest None Declared