BACKGROUND: The authors describe a 15-year experience with Gustilo grade IIIB fractures of the midtibia based on the type and timing of soft-tissue coverage. METHODS: A retrospective chart review was performed and patient demographics, risk factors, choice and timing of coverage, fracture outcome, and limb survival data were collected. RESULTS: Sixty-five fractures were treated. Soft tissue coverage was performed either acutely [<1 week (48 percent)] or delayed [>1 week (52 percent); with either a soleus muscle flap [group A; n = 25 (38 percent)] or a free tissue transfer [group B; n = 40 (62 percent)]. In group A, 17 (68 percent) were performed acutely (subgroup A1) and eight (32 percent) were delayed (subgroup A2). In subgroup A1, eight (47 percent) had uncomplicated healing, whereas seven (41 percent) ended in nonunion. In subgroup A2, all eight patients went onto nonunion. The overall limb survival rate for group A was 92 percent (n = 23). In group B, 14 (35 percent) were performed acutely (subgroup B1) and 26 (65 percent) were delayed (subgroup B2). In subgroup B1, six (43 percent) had uncomplicated healing, and six (43 percent) ended in nonunion. In subgroup B2, six (23 percent) healed primarily, and 17 (65 percent) went onto nonunion. The overall limb survival rate for group B was 88 percent (n = 45). CONCLUSIONS: Soft-tissue coverage is not the only determinant for successful outcome. Delayed coverage resulted in higher nonunion rates. Despite high nonunion rates, 89 percent of fractures ultimately healed successfully.