Depending on your particular history and exam, the doctor may suggest X-rays of the knee. X-rays show fractures (broken bones) and dislocations of bones in the knee as well as arthritis and abnormally large or small joint spaces.
Rarely, the doctor may order a CT scan (a 3-dimensional X-ray) of the knee to precisely define a fracture or deformity.
Both X-rays and CT scans are excellent for diagnosing fractures. They both are also poor, however, at evaluating soft tissue structures of the knee such as ligaments, tendons, and the menisci.