While supracondylar (SC) fractures are relatively common in children, the incidence of open injuries is believed to be only 1%. Two prior studies on open SC fractures in children reported an increased incidence of vascular injuries. The purposes of our study were to clarify the incidence, associated conditions, and current treatment for open SC fractures. The Pennsylvania Trauma Outcome Study database was queried. Subjects age 25 to 156 months old admitted to trauma centers between January 2000 and December 2015 with a SC fracture were included. Controls were those with closed fractures and the study group, those with open injuries. Study variables were age, sex, weight, injury severity score, length of stay (LOS), nerve injury, ipsilateral forearm fracture, compartment syndrome/fasciotomy, requirement for a vascular procedure. Other variables were mode of treatment, provisional reduction, repeat reduction, time interval between referring facility admission and operation, and time from emergency department admission to operation. A total of 4308 subjects were included, 104 (2.4%) of whom had an open SC fracture. LOS was 2 days for the study group versus 1 day for controls (P<0.001). Open SC fractures were more likely than closed to be associated with a nerve injury (13.5% vs. 3.7%), ipsilateral forearm fracture (18.3% vs. 6.4%) and/or a vascular procedure (6.7% vs. 0.3%) (P<0.001). 5.9% of those in the study group required repeat surgery compared with 0.4% for controls (P<0.001). Time from emergency department admission to operation was 3.2 versus 10.3 hours (P<0.001). We report the largest series to date of open SC fractures in children. Surgeons caring for such patients should be aware of their increased risks for both associated injuries and potential requirement for vascular reconstruction. The majority of children with an open SC fracture are managed with 1 operation and in the absence of vascular injury, seldom require an extended LOS. Level III-retrospective cohort study.