This x-ray shows a malignant bone tumor (osteogenic sarcoma) of the knee. This type of tumor is usually seen in adolescents (around 15 years old). This tumor extends from the bone into the surrounding tissue.
Update Date 5/9/2015
Updated by: C. Benjamin Ma, MD, Professor, Chief, Sports Medicine and Shoulder Service, UCSF Department of Orthopaedic Surgery, San Francisco, CA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.