The aim of this study is to determine if antibiotics affect the outcome after percutaneous surgery for pediatric supracondylar humerus fractures. The patient population will be recruited from the cohort presenting to Women and Children's Hospital for percutaneous fixation of pediatric supracondylar humerus fractures who meet the eligibility criteria and consent to taking part in the study. Patients will be followed up for 3-6 weeks depending on age, and will be evaluated on the presence or absence superficial or deep infection, Visual Analog Scale pain scores, time to healing, need for repeat casting, and loss of fixation.

This patient population will be recruited from the cohort presenting to Women and Children's Hospital for percutaneous fixation of pediatric supracondylar humerus fractures. Participants will be asked to assent to take part in the study and their parents or guardian will be asked to sign an informed consent. Patients will be randomized to a treatment group that receives one dose of pre-operative antibiotics or one that does not. Patients randomized to preoperative antibiotics will receive 25mg/kg cefazolin IV up to 1g or clindamycin 10mg/kg up to 600mg IV in cases of documented allergy to cefazolin. Patients randomized to the no-antibiotic group will receive a saline placebo. The resident, anesthesiologist, circulating nurse and other operating room staff will be instructed to not reveal the patient's randomization to the attending physician so as not to interfere with blinding.

The patient will then undergo closed reduction percutaneous pinning of supracondylar humerus fracture. Final AP and lateral fluoroscopic images in the case will be taken. The patient will be discharged from the hospital when pain is controlled with standard oral pain medications and all goals of inpatient management have been achieved. No patients will receive post-operative antibiotics regardless of randomization group as is the existing standard of care. Patients will be scheduled to follow up in 3-6 weeks depending on age. At that time the cast will be removed and AP and lateral radiographs will be used to assess healing. The pins will be removed in clinic and a soft dressing applied to the elbow region.

In cases of excessive pain or cast loosening the patient may be seen in clinic earlier with radiographs and physical exam as indicated. If the attending physician determines that a deep or superficial infection is present at any time during the treatment period the patient will be categorized as infected. If no infection is detected at an earlier-scheduled appointment the patient will be recasted and instructed to follow up as previously scheduled.

Inclusion Criteria:

• Age<14 years
• Open growth plates
• Gartland type II or III extension type fracture of the distal humerus OR Flexion type fracture of the distal humerus

Exclusion Criteria:

• Need for open reduction
• Need for antibiotics due to other injuries or conditions during the entire study period
• Immunosuppression
• History of malignancy or metabolic bone disease
• Open fractures
• Pre-existing Infection
• Intra-operative breech of sterile technique

Approximately 6 weeks or until the fracture is healed.

There is no difference in the definition of adverse event and/or serious adverse event from that of clinicaltrials.gov.

Randomization envelops will be created. Attending surgeons/Investigators will be blinded. Participant will be blinded.