Kinematic device for producing precise incremental flexing of the knee

A kinematic device, for use with magnetic resonance imaging (MRI) apparatus having an aperture, for producing precise incremental flexing movement of the knee of a human patient while substantially avoiding movement of the flexure point of the knee in its sagittal plane, movement of said knee perpendicular to said plane and any movement of the associated thigh comprising:

• a horizontal platform movable into said aperture for carrying at least the knee of one leg of said patient into an imaging volume in said aperture, said one leg also having a thigh;
• means mounted on said platform for elevating the other leg of said patient to allow movement of the calf of said one leg under said elevated leg in said sagittal plane and to allow positioning of the patient substantially on his side whereby full flexure of said knee is allowed;
• means for clamping said thigh to a fixed location on said platform;
• means mounted for rotation on said platform in a horizontal plane and having a center of rotation;
• means for clamping said calf to and for rotation with said means for rotation and for locating said flexure point of said knee at said center of rotation;
• means for incrementally rotating said means for rotation whereby said knee is incrementally flexed.