Primary malignant bone tumours of the distal tibia are very rare. Amputation was the standard surgical treatment with satisfactory functional results obtained using an appropriate prosthesis 
. But in the era of limb salvage, tumours of distal tibia are being dealt with limb salvage surgery to provide patients with a better quality of life 
We report a case of limb salvage for non-metastatic osteosarcoma of the distal tibia using resection and reconstruction with custom mega prostheses and ankle arthrodesis 
Osteosarcomas of the distal tibia are rare. These tumours are usually treated with amputation . We report a case of osteosarcoma of distal tibia in a 13year old female. The patient presented with complaints of pain and limping gait of 6 months’ duration. Imaging revealed a mixed lesion predominantly sclerotic with moth-eaten appearance, aggressive periosteal reaction in distal tibia. MRI revealed soft tissue involvement.
The patient received four cycles of neoadjuvant chemotherapy  she had a good clinical response by clinical and imaging evaluation. A distal tibial resection with custom mega prostheses reconstruction was done. The post-operative histopathology revealed an osteoblastic variant of osteosarcoma with 60% of necrosis. The patient completed two more cycles of same chemotherapy  the patient was on follow up since four months.
The post-treatment functional evaluation was done with “Revised Musculoskeletal Tumour Society Rating Scale . And patient had a score of 26 of 30. The patient was able to walk without crutches