Patella Osteomyelitis Masquerading as Prepatellar Bursitis

Osteomyelitis of the patella is a rare disease primarily affecting the pediatric population. Because it often presents with nonspecific symptoms, such as fever and pain, the diagnosis and treatment can be delayed. Prepatellar septic bursitis is also rare in the pediatric population; if left untreated it can progress to patella osteomyelitis. We present a case of prepatellar bursitis that progressed to septic knee arthritis and severe patella osteomyelitis in a 5-year-old male patient. This case demonstrates the importance of further evaluation and close follow up of suspected prepatellar bursitis in pediatric patients with consideration of magnetic resonance imaging (MRI) to monitor for early patella osteomyelitis, an uncommon but treatable disease.