[Sleeve fracture of the patella: A diagnosis not to be underestimated].

Fracture of the patella is quite rare in children. However, sleeve fractures of the patella are specific to the child. We report on the case of a 12-year-old boy who suffered complete functional incapacity with hemarthrosis and symptoms that suggested rupture of the extensor apparatus. It occurred after abrupt extension of the knee during a high jump. The x-ray showed an ascended patella. The diagnosis was made and emergency surgical exploration showed a sleeve fracture. Surgical repair provided a good result, with a 2-year follow-up. A literature review found 59 cases in 20 studies with a majority of case reports with only two series over ten cases. The ages and mechanisms are identical to those observed in our study. Diagnosis is difficult and must be clearly determined. The two important signs are the ascension of the patella and the depression to its lower extremity. The prognosis is most often conditioned by rapid surgical repair.