Abstract: A device for evaluating the patellafemoral joint is provided herein. The device measures movement of the patella in response to a lateral test force applied against the patella by a displacer, when the leg is supported in a flexed, relaxed position. The testing device includes a monitor which measures displacement of the patella. The monitor includes a monitor base that is secured to the leg of a patient and a contact arm which moves with the patella. The magnitude of the test force can be correlated with the degree of leg flexion and displacement of the patella to indicate the health and condition of the tissues in the knee which resist dislocation and movement of the patella.