Anatomic fracture brace for the knee

Claim 1

A brace mechanism having a four-bar linkage for use in a paired arrangement on each side of a user's leg in an anatomic knee brace comprising: a. a first extension link with an upward extension portion adapted and constructed to align with a user's leg on above the knee, and with a lower portion, having first and second spaced pivots; b. a second extension link with a downward extension portion adapted and constructed to align with a user's leg below the knee and with an upper end portion having spaced third and fourth pivots, said distance between said third and fourth pivots being greater than said first and second pivots; c. a third connecting link having a first end connected to said first pivot on said first link and a second end connected to said fourth pivot on said second link; d. a fourth connecting link having a first end connected to said second pivot or said first link and a second end connected to said third pivot on said second link, said fourth link crossing said third link; wherein upon vertical alignment of said extension portions, said first pivot is located on said end portion of said first link proximate said extension portion and said second pivot is displaced from said first pivot in a downward angled direction and, said third pivot is located on said end portion of said second link proximate said extension portion and said fourth pivot is displaced from said third pivot in an upward angled direction toward said second pivot, whereby said four-bar linkage is constructed and arranged to generate a polycentric motion with dual centers progressing from a common center point when said extension portions are aligned against a user's straight leg and diverging with asymmetric trajectories when said extensions portions are angled conforming to a user's bent leg, the asymmetric trajectories of the four-bar linkage approximately the asymmetric trajectories of the polycentric motion of user's knee.