Background: The value of employing an orthopedic technician or advanced practice provider (OT/APP) to assist trainees during on-call hours has not been assessed. As the third most common pediatric long bone fracture, most tibial fractures can be managed with closed reduction and casting. Purpose: We sought to determine whether clinical outcomes could be positively affected for traumatic childhood tibia fractures by using an experienced OT/APP to aid orthopedic surgery residents with closed reduction and casting. Methods: We performed a retrospective chart review of tibial shaft fractures that occurred between 2010 and January 2017. Fractures undergoing manipulation and closed reduction by orthopedic surgery residents (post-graduate year 2 to 4) in the emergency department were included and differentiated into 2 cohorts: (1) residents who performed the procedure alone and (2) residents who were assisted by an OT/APP. Comparisons in cast quality and treatment success were made using univariate statistics followed by a multivariate Classification and Regression Tree (CART) analysis. Results: Of the 73 patients who met our criteria, 38 received treatment by a resident alone and 35 by a resident assisted by an OT/APP. Evidence to support our hypothesis was found with the resident-alone group "over" padding the casts posteriorly. Univariate analysis demonstrated that the rate of subsequent surgical intervention was more than double in the resident-alone group (31% vs 14%), yet OT/APP castings underwent more wedging at follow-up (17% vs 0%). CART analysis revealed initial fracture severity and lack of OT/APP assistance as predictors of surgical intervention with terminal nodes, in increasing order of risk of requiring surgical intervention: lower translation on sagittal and anteroposterior (AP), lower sagittal translation with greater AP translation, greater sagittal translation with OT/APP assistance, and greater sagittal translation without assistance. The initiation of a cast application-training program in 2015 decreased the need for surgical treatment in the resident-only group (pre-program 38.5% vs post-program 17%), although this was not statistically significant. Conclusion: When residents were assisted by OT/APP with initial tibia closed reduction and casting, subsequent loss of reduction was more likely to be managed with cast wedging; when this assistance was not available, there was a higher rate of fractures needing surgical intervention due, in part, to poor casting technique. The reduction in the rate of surgical intervention after an internal training program was implemented suggests that trainees may improve their casting ability without added help of an experienced assistant. Future study should be performed on distal radius fractures to determine if the presented findings are valid across casting types.