Patellofemoral joint imaging study: State of the art

Abstract

Anterior knee pathology is frecuent in clinical practice. Patello femoral dysfunction is a syndromic condition of broad etiology frequently associated with a failure in the entry of the patella into the trochlea that causes overload and wear of the articular cartilages, determining a higher risk of osteoarthritis in the long term. The clinical presentation is varied. It is a dynamic problem, where anatomical factors of the joint geometry and its stabilizing mechanisms influence. The imaging study includes different techniques with different uses. The simple X-ray is the initial examination. Computed tomography and magnetic resonance imaging, both techniques with greater resolution of space and contrast, allow evaluating other aspects of the joint and the relationship of the patella with the femoral trochlea, in addition to the rotational aspects of the lower limb. None of them alone provides all the information necessary for the therapeutic decision. In this article we review the clinical presentations and the imaging study. We discuss and propose a study protocol with X-ray and magnetic resonance imaging that includes the most useful validated objective measurements of the anatomical factors that condition instability in the different clinical presentations.