The aim of this study was to investigate the clinical efficacy of free dermatoplasty combined with vacuum sealing drainage (VSD) for the treatment of large-area soft tissue defects accompanied by bone exposure in the lower leg (crus). Free dermatoplasty combined with VSD was used to treat 36 patients with large-area soft tissue defects accompanied by bone exposure in the lower leg. The areas of the soft tissue defects ranged from 25×12 to 35×30 cm and the areas of exposed bone ranged from 6×4 to 10×6 cm. When evaluated by the open fracture Gustilo classification, 14 cases were of Gustilo type IIIA and 22 cases were of type IIIB. During surgery, adjacent available muscle flaps were transferred to cover the outer areas of the exposed bone and reduce the bone exposure range. Following VSD treatment, granulation tissues grew well and free dermatoplasty combined with VSD was used to treat and repair the wound surfaces. The patients were followed up for 1–5 years (mean duration, 2.5 years). All 36 cases with skin flap grafts survived, the free skin graft texture on the wound surface was good, the recovery of lower limb function was satisfactory and the success rate was 80.56%. Free dermatoplasty combined with VSD used for the treatment of large-area soft tissue defects accompanied by bone exposure in the lower leg may eliminate the need for amputation and complex surgery, and is a simple, fast and effective treatment method.