A 28-year-old woman presented to the emergency department with left lateral knee pain after a motor vehicle crash. There was no indication of superficial trauma or deficit on physical examination. Plain radiographs of the left knee (image A and image B) showed patella fragments, which were determined to be secondary to congenital bipartite patella.¹ The patient was treated conservatively with nonsteroidal anti-inflammatory drug therapy, and rest, ice, compression, and elevation were suggested. 

Bipartite patella is caused by a failure in ossification of the patellar cartilage at its secondary ossification center.² Bipartite patella is usually asymptomatic, but symptoms can be exacerbated by physical activity secondary to microtrauma.³ Management is dependent on the degree of disability. Conservative management includes restriction of activity, nonsteroidal anti-inflammatory drug therapy, and corticosteroid joint injections for sustained pain relief.^1,4 If conservative management fails or symptoms worsen, surgical intervention may be necessary.