Abstract:[Objective] To investigate the efficacy of distally based sural flap (DBSF) for traumatic middle-lower tibiofibular and foot osteomyelitis complicated with skin and soft tissue defect, and to analyze the factors affecting the recurrence of osteomyelitis. [Methods] A total of 174 patients received DBSF for traumatic middle-lower tibiofibular and foot osteomyelitis complicated with skin and soft tissue defect from November 2003 to February 2021. The function of the affected limb was evaluated according to the modified Association for the Study and Application of the Method of Ilizarov (ASAMI) scoring system. The factors influencing the recurrence of osteomyelitis were analyzed by univariate comparison and binary multifactor logistic regression. [Results] Of 174 patients, 12 cases (6.9%) got partially necrotic flap, while 162 cases (93.1%) had completely alive flap. On other hand, 22 cases (12.6%) had osteomyelitis recurred, whereas 152 cases (87.4%) got primarily cured. According to the modified ASAMI criteria, 74 cases (42.5%) were excellent, 83 cases (47.7%) were good, 14 cases (8.0%) were fair, and 3 cases (1.7%) were poor, with an overall excellent and good rate of 90.2% at the last follow-up. Regarding univariate comparison, there were no significant differences in gender composition, lesion location, anatomic classification of osteomyelitis, flap area and fracture management between the recurrence group and the cure group (P>0.05). However, the recurrence group proved significantly greater than the cure group in age and course of disease (P<0.05). As consequence of logistic regression, the old age (OR=1.024, P=0.046), long course of disease (OR=4.664, P=0.004) and severe Cierny-Mader IV classification (OR=4.086, P=0.041) were independent risk factors for osteomyelitis recurrence. [Conclusion] Distally based sural flap combined with appropriate osteomyelitis treatment is an effective method for traumatic middle-lower tibiofibular and foot osteomyelitis complicated with skin and soft tissue defect. The recurrence rate of osteomyelitis is closely related to Cierny-Mader classification, course of disease and age of patients.