Intervertebral spinal implant and method
A spinal implant is provided. The spinal implant includes a body extending between a proximal end and a distal end. The proximal end defines a notch configured for disposal of a first vertebra. The distal end includes a protrusion configured for disposal in a second vertebra. The proximal and distal ends are movable relative to one another between an unexpanded position in which the spinal implant is inserted between lamina and an expanded position in which the spinal implant is disposed between the lamina.
1. A spinal implant, comprising: a body extending between a proximal end and a distal end, the body including an expandable intermediate portion disposed between the proximal end and the distal end, the body comprising a shape memory material, the proximal end defining a notch configured for disposal in a first vertebra, and comprising a first mating part, the distal end comprising a protrusion configured for disposal in a second vertebra, and a second mating part, wherein the proximal and distal ends are movable relative to one another between an unexpanded position in which the spinal implant is configured to be inserted between lamina and an expanded position in which the spinal implant is configured to be disposed between the lamina, and the first mating part is configured to engage the second mating part in the unexpanded position, and the spinal implant is configured to move in the expanded position when the proximal end and the distal end are rotated relatively to one another to disengage the first mating part with the second mating part.
2. A spinal implant as recited in claim 1 , wherein the intermediate portion includes a biasing member, the biasing member resiliently biasing the body to the expanded position.
3. A spinal implant as recited in claim 1 , wherein the protrusion includes a roughened outer surface.
4. A spinal implant as recited in claim 1 , wherein the protrusion has a rounded distal tip.
5. A spinal implant as recited in claim 1 , wherein the protrusion has a cone-shaped configuration.
6. A spinal implant as recited in claim 1 , wherein the protrusion is movable relative to the distal end.
7. A spinal implant as recited in claim 1 , wherein the protrusion has a pointed distal tip configured for penetrating engagement with spinal tissue.
8. A spinal implant as recited in claim 1 , wherein the first vertebra includes an inferior lamina and the second vertebra includes a superior lamina.
9. A spinal implant as recited in claim 1 , wherein the body further comprises at least one of stainless steel alloys, commercially pure titanium, titanium alloys, Grade 5 titanium, cobalt-chrome alloys, stainless steel alloys, calcium phosphate, polyaryletherketone (PAEK), polyetheretherketone (PEEK), polyetherketoneketone (PEKK), polyetherketone (PEK), carbon-PEEK composites and PEEK-BaSO4.
10. A spinal implant as recited in claim 1 , wherein the body is cannulated along its length.
11. A spinal implant as recited in claim 1 , wherein the shape memory material comprises shape memory polymers such as polyurethanes, polyurethanes with ionic or mesogenic components, block copolymers comprising polyethyleneterephthalate and polyethyleneoxide, block copolymers containing polystyrene and polybutadiene, polyesterurethanes with methylenebis and butanediol, and epoxy resins.
12. A spinal implant as recited in claim 1 , wherein the spinal implant is bullet shaped.
13. A spinal implant as recited in claim 1 , wherein each mating part includes a hook.
14. A spinal implant, comprising: a body extending between a proximal end and a distal end, the proximal end comprising a first mating part, and the proximal end is configured for disposal in a first vertebra, the distal end comprising a second mating part, and the distal end is configured for disposal in a second vertebra, wherein the proximal and distal ends are movable relative to one another between an unexpanded position in which the spinal implant is configured to be inserted between lamina and an expanded position in which the spinal implant is configured to be disposed between the lamina so as to allow elasticity during motion, and the first mating part is configured to engage the second mating part in the unexpanded position, and the spinal implant is configured to move in the expanded position when the proximal end and the distal end are rotated relatively to one another to disengage the first mating part with the second mating part, the spinal implant being bullet shaped, and the body comprising a shape memory material.