Osteonecrosis with Concomitant Septic Arthritis of Bilateral Hips following Severe COVID-19 Infection: A Case Report.

Introduction: Among the various musculoskeletal manifestations of post-acute Coronavirus disease 2019 (COVID-19) syndrome, osteonecrosis and pyogenic infections are of serious concern due to their potential for joint destruction and the need for major surgery, even among young patients. Spontaneous septic arthritis is rare among healthy adults. Very few cases of osteonecrosis of the femoral heads (ONFH) with concomitant septic arthritis of the hip following a COVID-19 infection are reported in the literature. Case Report: We report the case of a 43-year-old male patient, who presented with bilateral ONFHs and concomitant septic arthritis of the hips (caused by Pseudomonas aeruginosa), 8 weeks following a severe COVID-19 infection. His serum inflammatory markers were elevated. Radiologic findings were equivocal, and suggestive of osteonecrosis, with possible septic arthritis of the hip. In view of disabling end-stage arthritis, he was advised bilateral total hip arthroplasty (THA), in one or two stages, depending on the intraoperative findings. The diagnosis of infection was confirmed through intraoperative frozen section analysis. Bilateral two-staged THA was performed. At 3 years' follow-up, the patient had no recurrence of symptoms, and was found to be doing well, with a Harris Hip Score of 93 points, and no limb length discrepancy. Conclusion: COVID-19 infection predisposes patients to the development of ONFH. Concomitant septic arthritis of the hip, however, is scarcely reported, and needs to be ruled out in cases with rapid progression of symptoms.