[Staged treatment of infectious long bone defect in lower extremity].

OBJECTIVE: To explore the clinical application and effectiveness of antibiotic-loaded cement spacer combined with free fibular graft in the staged treatment of infectious long bone defect in the lower extremity.

METHODS: A retrospective analysis was made on the clinical data from 12 patients with infectious long bone defect in the lower extremity between June 2010 and June 2012. Of the 12 cases, there were 9 males and 3 females with an average age of 33 years (range, 19-46 years), including 3 cases of femoral shaft bone defect, 7 cases of tibial shaft bone defect, and 2 cases of metatarsal bone defect. The causes were traffic accident injury in 7 cases, crashing injury in 3 cases, and machine extrusion injury in 2 cases. The length of bone defect ranged from 6 to 14 cm (mean, 8 cm). The soft tissue defect area ranged from 5.0 cm x 3.0 cm to 8.0 cm x 4.0 cm companied with tibial shaft and metatarsal bone defect in 9 cases. The sinus formed in 3 femoral shaft bone defects. The time between injury and operation was 1-4 months (mean, 2 months). At first stage, antibiotic-loaded cement spacer was placed in the bone defect after debridement and the flaps were used to repair soft tissue defect in 9 cases; at second stage (6 weeks after the first stage), defect was repaired with free fibular graft (7-22 cm in length, 14 cm on average) after antibiotic-loaded cement spacer removal. The area of the cutaneous fibular flap ranged from 6.0 cm x 4.0 cm to 10.0 cm x 5.0 cm in 10 cases.

RESULTS: All wounds healed by first intention, and the healing time was 12-18 days, 14 days on average. Twelve cases were followed up 12-36 months (mean, 17 months). Bone healing time ranged from 4 to 6 months (5.5 months on average). The cutaneous fibular flap had good appearance. The function at donor site was satisfactory; no dysfunction of the ankle joint or tibial stress fracture occurred after operation. The mean Enneking score was 25 (range, 20-28) at last follow-up.

CONCLUSION: Infection can be well controlled with the antibiotic-loaded cement spacer during first stage operation, and free fibular graft can increase the bone defect healing rate at second stage. Staged treatment is an optimal choice to treat infectious long bone defect in the lower extremity.