Patent ID: 6572653
Filing Date: 2003-06-03
Classification: A61F,Y10S

Abstract:
A vertebral implant adapted for posterior insertion and designed to replace the fibrocartilage between the facing surfaces of adjacent superior and inferior lumbar vertebrae, each of the vertebrae having a posterior edge and pedical, the implant comprising:a pair of hydroxyapatite coated superior supports, each support having first and second ends, a plate portion and a lip portion, the lip portion being formed at an angle to the plate portion at the first end of the support, the plate portion having a plurality of teeth, a retainer and a pair of side edges, the side edges tapering from the second to the first end of the support, the plate portion of each support being received within a channel formed within the facing surface of the superior vertebrae such that the lip portion abuts the posterior edge of the vertebrae; a pair of hydroxyapatite coated inferior supports, each support having first and second ends, a plate portion and an offset lip portion, the offset lip portion being formed at a right angle to the plate portion at the first end of the support, the plate portion having a plurality of teeth, a retainer and a pair of side edges, the side edges tapering from the second to the first end of the support, the plate portion of each support being received within a channel formed within the facing surface of the inferior vertebrae such that the offset lip portion abuts the pedical and the posterior edge of the vertebrae, the pair of inferior supports being position opposite to the superior supports; a pair of springs, each spring being formed from a plurality of oblong coils and tapering from a second to a first end, each spring positioned between the side edges of opposing superior and inferior supports with the position of the spring being fixed by the retainers of the opposing superior and inferior supports, each spring having an axial force under compression that functions to drive the teeth of the opposing superior and inferior supports into the facing surfaces of the adjacent vertebrae.