The sunrise view is a tangential look at the flexed knee, with the patient positioned so that the patella is perpendicular to the film.

Looking at this radiograph, you can orient yourself to right and left by knowing that the medial condyle of the femur is usually more rounded and/or prominent than the lateral, or by identifying the head of the fibula.

The sunrise view is not part of most routine knee series, but rather is used to specifically assess the patellofemoral articulation. Osteoarthritis (degenerative joint disease) of the posterior patellar articular cartilage and/or anterior articular cartilage of the femur may be seen as malalignment (or tilting) of the patella or narrowing of the joint space.