Adjustable intervertebral implant

An adjustable intervertebral implant for implanting between adjacent vertebrae bodies to replace all or a significant portion of a damaged vertebra, the adjustable intervertebral implant comprising:

• an inner member having a longitudinal axis extending between a first end and a second end, an outer surface, a throughslot extending from the second end along the longitudinal axis, a first threading on the outer surface;
• an outer member having a longitudinal axis extending between a first end and a second end, an internal surface, an outer surface, a tab protruding from the first end along the longitudinal axis and terminating in a lip protruding substantially perpendicular to the longitudinal axis of the outer member, the inner member slidably received within the outer member and being slidably movable along the longitudinal axis, the slidable movement guided by interaction of the tab protruding from the outer member with the throughslot formed in the inner member;
• an expansion ring having inner and outer surfaces, the inner surface having a second threading thereon, the expansion ring received around the tab protruding from the outer member and below the lip so as to be freely rotatable with respect to the outer member, rotation of the expansion ring resulting in engagement of the first and second threading and translation of the inner member with respect to the outer member, the expansion ring further including a plurality of unthreaded throughslots disposed circumferentially around the expansion ring;
• and
• at least one set screw having a head and a threaded shaft, wherein advancement of the set screw within a corresponding throughslot causes the distal end of the set screw to bear against the outer surface of the inner member and thereby secure the inner member relative to the outer member in a locked position.

An adjustable intervertebral implant for implanting between neighboring vertebral bodies to replace all or a significant portion of a damaged vertebra, the adjustable intervertebral implant comprising:

• a radiolucent inner member having a longitudinal axis extending between a first end and a second end, an outer surface, a throughslot extending from the second end along the longitudinal axis, a first threading on the outer surface;
• a radiolucent outer member having a longitudinal axis extending between a first end and a second end, an outer surface, the inner member slidably received within the outer member and being slidably movable along the longitudinal axis;
• a radiographically visible expansion ring having inner and outer surfaces, the inner surface having a second threading thereon, wherein a width of crests of the first threading is greater than a width of the crests of the second threading, the expansion ring being rotatably coupled to the outer member so that rotation of the expansion ring results in engagement of the first and second threading and slidable translation of the inner member with respect to the outer member, the expansion ring further including a plurality of unthreaded throughslots disposed circumferentially around the expansion ring;
• at least one set screw wherein advancement of the set screw within a corresponding throughslot causes a distal end of the set screw to bear against the outer surface of the inner member and thereby secure the inner member relative to the outer member in a locked position.