Abstract: A spinal disc prosthesis to replace a damaged spinal disc in a spinal column of a human includes an upper rigid plate having an outer perimeter and a lower rigid plate having an outer perimeter. A body of elastomeric material located between and bonded to the upper and lower rigid plates includes a main portion and a peripheral portion extending around the main portion. The upper and lower plates each have a curved convex plate surface extending around the respective outer perimeters and facing the peripheral portion of the body of elastomeric material. The peripheral portion of the body of elastomeric material has a first part which is bonded to the curved convex plate surfaces of the upper and lower plates and extends toward the main portion. The first part of the peripheral portion increases in thickness as the first part extends from the curved convex plate surfaces toward the main portion.

Abstract: A method of forming a composite structure comprises the steps of forming a radially inner portion of a preform with braided reinforcing fibers extending substantially transverse to an axis of the preform and forming a radially outer portion of the preform circumscribing the inner portion with braided reinforcing fibers extending substantially parallel to the axis of the preform. The preform is heated and consolidated in a mold into the composite structure. The composite structure has braided reinforcing fibers extending throughout a radially inner portion substantially transverse to an axis of the structure along which the structure is subject to splitting to resist splitting of the composite structure along the axis and braided reinforcing fibers extending throughout a radially outer portion substantially parallel to the axis to resist bending of the composite structure. The composite structure is particularly suitable for manufacturing a bone plate.

Abstract: A spinal disc prosthesis comprises an upper rigid plate, a lower rigid plate, and an elastomeric core interposed between the plates and adhered to the plates. The elastomeric core has an upper portion with an outer peripheral surface extending substantially perpendicular to the upper plate. A lower portion of the elastomeric core has an outer peripheral surface extending substantially perpendicular to the lower plate. An intermediate portion of the elastomeric core, extending between the upper and lower portions, has a concave outer peripheral surface. Each of the upper and lower plates has a plurality of ribs extending into the elastomeric core to secure the elastomeric core to the upper and lower plates.

Abstract: A three-dimensional fiber reinforced composite structure which is made by providing yarn having of a plurality of continuous reinforcing fibers and fibers which when melted form a matrix material, randomizing the yarn, forming the randomized yarn into a preform, and consolidating the preform in one direction. Each of the plurality of reinforcing fibers extends continuously and randomly throughout the matrix because of the randomizing. The fiber reinforced composite structure is particularly suitable for manufacturing a vertebral prosthetic spinal implant device.

Abstract: A method of forming a three-dimensional fiber reinforced composite structure includes comprises the steps of providing yarn made of a plurality of continuous reinforcing fibers and fibers which when melted form a matrix material, randomizing the yarn, forming the randomized yarn into a preform, and consolidating the preform in one direction. Each of the plurality of reinforcing fibers extends continuously and randomly throughout the matrix because of the randomizing. The fiber reinforced composite structure formed by the present method is particularly suitable for manufacturing a vertebral prosthetic spinal implant device.