There are now recognized standards of care published by the British and American Orthopaedic Associations which detail key areas of evidence-based recommendations for the treatment of children with displaced supracondylar humerus fractures. Although many aspects of treatment are covered in these recommendations, both the American and British Orthopaedic Associations do not recommend the exact duration of immobilization postoperatively. This study retrospectively compared outcomes of operatively managed supracondylar fractures immobilized postoperatively for short immobilization (SI) defined as 28 days or less, with long immobilization (LI) defined as more than 28 days. The outcomes measured were clinical (deformity, range of motion, and pin site infection) and radiologic (loss of position after the removal of K-wires, Baumann's angle, anterior humeral line, refracture, and signs of osteomyelitis). Demographic data were recorded to evaluate and ensure satisfactory matching of the 2 groups for analysis. The study included 193 pediatric supracondylar fractures over a 4-year period which were treated with manipulation under anesthetic and K-wire fixation. The difference in average time in plaster between the 2 groups was statistically significant (SI: n=27.5d, SD 1.23; LI: n=43.9d, SD 15.29, P =0.0001). Data for operative techniques-closed or open reduction (SI: n=66, LI: n=78, P =0.59), and crossed wires (SI: n=37, LI: n=50, P =0.57) between the two groups showed no statistical significance. There was no statistical difference between the groups for the average number of days postoperatively at which wires were taken out (SI: n=28.9d, SD 5.95, LI: n=30.1d, SD 5.57, P =0.15), number of pin site infections requiring antibiotic treatment (SI: n=3, LI: n=5, P =0.70), or children from each group who were recorded to have regained full range of motion symmetrical to their contralateral arm (SI: n=79, LI: n=99, P =0.74). Our study therefore suggests that shorter immobilization of these patients (SI group) does not yield a higher rate of complications including refracture and malunion.