Figure 1.

(a) Coronal section MRI image of a bone sarcoma located in the right distal femur of an 11-year-old girl. Following the wide resection performed in the first stage, the projected adult period limb length discrepancy (LLD) was calculated as 8 cm. (b) Radiographic image at the 5-year follow-up of the tumor prosthesis placed for endoprosthetic reconstruction after the patient’s wide resection. The orthoroentgenogram shows that 4.5 cm of the 8 cm LLD originates from the femur and 3.5 cm from the tibia. Please note the dashed line indicating the alignment of the lower extremity and the osseointegration at the proximal bone-host implant junction. (c and d) Anteroposterior and lateral radiographs of the patient during lengthening from the ipsilateral tibial diaphysis with a computer-assisted external fixator. (e and f) Anteroposterior and lateral radiographs of the patient after 4 cm lengthening during the consolidation period. (g) Orthoroentgenogram with 4 cm compensation taken during the follow-up of the patient’s first lengthening surgery.