100 patients with acute long bone fractures and hypovitaminosis D were included in this trial to observe the potential relationship between vitamin D deficiency and nonunion. Acute long bone fracture patients identified as having hypovitaminosis D were randomized to receive a one-time oral dose of 100,000 IU vitamin D or a placebo within the first two weeks of fracture. Nonunion rate was similar between the two groups, with nonunion observed in two patients in each group, respectively. Additionally, during patient screening for inclusion it was observed that 89% of patients that presented to the level-1 trauma center with a long bone fracture had hypovitaminosis D.