If the pain doesnt reflect the anatomical problem, how can your doctor know whats behind it? It starts with a good history and a physical examination, Dr. Murray says. Certain clues can point a diagnosis away from the knees and toward the hips. If the knee has good range of motion and no tenderness but the hip has poor range of motion, then youre tipped off that maybe this is somebody who has a hip problem and not a knee problem, says Dr. Murray. An X-ray should confirm the diagnosis by revealing joint erosion and cartilage loss in the hip and intact joints in the knees.