Limb salvage is a key goal of tumor management around the knee, with surgical, medical, and radiologic treatment options. Primary bone and soft tissue sarcomas are optimally treated in specialist tertiary centers; however, metastatic disease is encountered in all aspects of radiologic practice, with overlap in the management strategies. Both specialist and generalist radiologists therefore need to be familiar with the expected normal appearances following these therapies and be able to recognize potential complications. This review article describes the techniques available for imaging the knee following treatment of bone and soft tissue tumors, with particular reference to artifact reduction. The therapeutic options for managing bone and soft tissue lesion are discussed, with emphasis on imaging appearances. Surgical, medical, and radiologic treatments are described. Complications and their imaging appearances are reviewed including local recurrence of tumor, infection, complications related to metallic implants, postradiation changes, and amputation. Normal imaging appearances and complications following radiologic treatment (namely radiofrequency ablation) of bone and soft tissue tumors are presented.