Magnetic resonance imaging screening for osteonecrosis of the femoral head after coronavirus disease 2019

Objectives Systemic steroid administration has been suggested for the treatment of coronavirus disease 2019 (COVID-19), but the occurrence of osteonecrosis of the femoral head (ONFH) was one of the concerns for this treatment. This study aimed to use magnetic resonance imaging (MRI) to assess the incidence of ONFH after the treatment for COVID-19.Methods The study included 41 patients who were hospitalized and treated for pneumonia or other COVID-19-induced diseases. We conducted interviews with these patients regarding hip pain and performed MRI screenings for ONFH. The incidence and timing of ONFH after COVID-19 treatment were investigated.Results Of the 41 patients, one died of pneumonia and the remaining patients did not complain of hip pain. MRI screening was performed for 26 patients, and asymptomatic ONFH was detected in one patient (3.8%) whose ONFH appeared 1 month after the COVID-19 infection.Conclusions Our MRI screening of ONFH in post-COVID-19 patients revealed asymptomatic ONFH, which would not have been identified without active screening. Physicians should be aware that ONFH may occur in patients after treating COVID-19.