Expandable fabric implant for stabilizing the spinal motion segment

A device for use in stabilizing a spinal motion segment comprising:

• a generally hollow, flexible bag adapted for expansion solely by the introduction of graft material, said bag being further characterized by the absence of any other expansion means, said bag including at lest one fill opening into which biological fill material for promoting bony or fibrous union may be inserted, said bag being filled with biological fill material to a rigid state, said flexible bag including a plurality of pores, said pores being sized to allow ingress and egress of liquids, solutions, small particle suspensions and ingrowth of bony trabeculae or fabrous elements into and through said device when said device is positioned in a hollowed region of an intervertebral space, said pores being sized to retain said fill material within said bag;
• said bag further including closure means for closing said fill opening to prevent egress of said fill material from said bag, wherein said bag is generally spherical in shape, having an equator defined by a line extending circumferentially around a periphery of the spherical shape, an axis and an equatorial band, said equatorial band having greater rigidity than the remainder of said bag causing a force to be directed in a predefined direction.