Ankle-foot orthosis

Claim 1

An easily removable orthosis (11) for maintaining an ankle and a foot in a substantially 90° relationship to one another, said orthosis comprising a generally boot shaped structure including a foot portion (40) and a leg portion (42) disposed in a substantially 90° relationship to one another, said structure being composed of a continuous inner liner of foamed plastic (24) surrounded by a continuous outer layer of vacuum formable plastic film (25), a protrusion in the ankle joint area, the portions of said outer layer adjacent the medial and lateral surfaces of the ankle joint of a wearer being deformed for defining a pair of opposed exteriorly protruding longitudinal ribs (18), (20); said protrusion and ribs reinforce the rigidity of said outer layer for inhibiting flexion of the wearer's ankle joint, said boot shaped structure further including a continuous longitudinal opening (46) extending adjacent the dorsal surface of the foot and anterior surface of the leg of a wearer for facilitating removal of and entrance into said structure and binding means (50) across said opening for snugly fitting said structure to a wearer and having the ability of only partially closing the continuous opening and further having a rigid boot portion (70) placed below the foot portion (40) so as to cause limitation of motion at ankle and subtalar joints during ambulation of the wearer; wherein said foot portion includes a sole means (51) and the sole means varies in thickness and is bio-mechanically designed to allow for a forward motion of the leg over the foot so as not to over-extend the knee in propulsion.