Early Postoperative Infections After Closed Reduction and Percutaneous Pinning in Type II and Type III Pediatric Supracondylar Humerus Fractures

Background: Supracondylar humerus fractures (SCHF) are the most common elbow fracture type in children, and one of the most common pediatric fracture types overall. Excellent outcomes are generally reported with closed reduction and pinning (CRPP), but the technique involves leaving the pins outside the skin. External pins can act as a nidus for infection. We characterize the infection complications from SCHF treatment at a single-centre tertiary children's hospital over 10 years. This is the largest series on infectious outcomes after CRPP of SCHF reported to date. Methods: Pediatric patients undergoing CRPP for a type II or type III SCHF from 2011 to 2021 with postsurgical infections within 90 days were identified. Demographic and clinical data were retrieved from medical records. Descriptive statistics were estimated and reported as means or medians with range values or counts with percentages. Results: A total of 18 patients met inclusion criteria, 10 and 8 with type II and III SCHF, respectively. The average age at diagnosis of fracture was 4.7 (2 to 9) years. The average operating time for the index surgery was 29 minutes (12 to 42). The average number of postoperative days until pin removal was 29.8 (18 to 52), and the average number of postoperative days until readmission or visit with symptoms was 38.9 (18 to 77). There was a documented history of a wet cast in 6 patients (33%). Ten (56%) patients presented with fever, and the most common positive culture was methicillin-sensitive Staphylococcus aureus (9, 50%). Thirteen (72%) patients returned to the operating room for incision and drainage. There were no cases with continued complications after the original infection after a median follow-up of 63 days (8 to 559). Infection after CRPP of SCHF is a rare adverse event. In our series, it was most often associated with common pathogens and wet casts. The necessity of return to the operating room will vary with the presentation, but if efficaciously treated afterwards with oral antibiotics, there is a low chance of recurrence or subsequent complications. Patients should be carefully instructed in cast care and demonstrate understanding of risks and complications, and to contact their orthopaedist if their cast demonstrates lack of integrity.