Customized Intervertebral Prosthetic Disc with Shock Absorption

Abstract

A prosthesis system comprises plates that can be positioned against vertebrae and a selected resilient core that can be positioned between the plates to allow the plates to articulate. The selected resilient core can be chosen from a plurality of cores in response to patient characteristics, such as age and/or intervertebral mobility, such that the prosthesis implanted in the patient is tailored to the needs of the patient. The plurality of cores may comprise cores with different resiliencies, and one of the cores can be selected such that the upper and lower plates articulate with the desired shock absorbing resiliency and/or maximum angle of inclination when the one selected core is positioned between the plates.

1 . An intervertebral disc prosthesis system comprising:
 a plurality of selectable cores, each core comprising,
 upper and lower surfaces, and 
 at least one of a resilient material or a resilient member disposed between the upper and lower surfaces to allow the upper and lower surfaces to move resiliently toward and away from each other; and 
   upper and lower supports locatable about the core, each support comprising,
 an outer surface which engages a vertebra, and 
 an inner surface shaped to contact one of the surfaces of each core; 
   wherein each core of the plurality comprises a different resiliency and wherein the upper and lower supports are adapted to articulate when one of the cores is selected and positioned between the upper and lower supports.   
   
   
       2 . The system of  claim 1 , wherein each core is identifiable with an indicia, such that each core is selectable in response to the indicia and a patient characteristic. 
   
   
       3 . The system of  claim 2 , wherein the indicia comprises at least one of a color of the core, a marking on the core, a height of the core, or a width of the core. 
   
   
       4 . The system of  claim 2 , wherein the indicia of each core corresponds to a resiliency of the core and a maximum angle of inclination between the supports when the core is positioned between the supports. 
   
   
       5 . The system of  claim 1 , wherein each core of the plurality comprises a different dimension to limit a maximum angle of inclination between the upper and lower supports in response to the patient characteristic. 
   
   
       6 . The system of  claim 5 , wherein the different dimension comprises at least one of a height or a width. 
   
   
       7 . The system of  claim 1 , wherein the upper surface of each core comprises a curved surface to slide against the inner surface of the upper support. 
   
   
       8 . The system of  claim 7 , wherein the lower surface of each core is capable of attachment to the lower support. 
   
   
       9 . The system of  claim 1 , wherein the lower surface of each core comprises a curved surface to slide against the inner surface of the lower support. 
   
   
       10 . The system of  claim 1 , wherein each core comprises an upper component with the upper surface disposed thereon and a lower component with the lower surface disposed thereon, wherein the upper and lower core components of each core are configured to slide relative to one another in response to loading when positioned between the upper and lower supports. 
   
   
       11 . The system of  claim 10 , wherein the upper and lower components of each core are configured to slide relative to one another with telescopic motion. 
   
   
       12 . The system of  claim 1 , wherein the upper support comprises a upper plate and the lower support comprises a lower plate. 
   
   
       13 . The system of  claim 1 , wherein the upper support comprises an upper expandable support and the lower support comprises a lower expandable support. 
   
   
       14 . The system of  claim 1 , wherein several cores of the plurality comprises the same height and different resiliencies, such that a maximum angle of inclination between the plates is substantially the same for the several cores. 
   
   
       15 . The system of  claim 1 , the plurality of selectable cores comprises cores with a maximum compression within a range from about ⅓ mm to about 1 mm. 
   
   
       16 . An intervertebral disc prosthesis system comprising:
 a plurality of selectable cores, each core comprising,
 upper and lower curved surfaces, and 
 at least one of a resilient material or a resilient member disposed between the upper and lower curved surfaces to allow the upper and lower surfaces to move resiliently toward and away from each other; and 
   upper and lower supports locatable about the core, each support comprising:
 an outer surface which engages a vertebra, and 
 an inner curved surface shaped to slide over one of the curved surfaces of each core; 
   wherein each core of the plurality comprises a different resiliency and wherein the upper and lower supports are adapted to articulate when one of the cores is selected and positioned between the upper and lower supports.   
   
   
       17 . The system of  claim 16 , wherein each core is identifiable with an indicia, such that each core is selectable in response to the indicia and a patient characteristic. 
   
   
       18 . The system of  claim 17 , wherein the indicia comprises at least one of a color of the core, a marking on the core, a height of the core, or a width of the core. 
   
   
       19 . The system of  claim 17 , wherein the indicia of each core corresponds to a resiliency of the core and a maximum angle of inclination between the supports when the core is positioned between the supports. 
   
   
       20 . The disc prosthesis system as in  claim 16 , wherein the at least one resilient material comprises a polymer. 
   
   
       21 . The disc prosthesis system as in  claim 16 , wherein the at least one resilient material comprises a hydrogel. 
   
   
       22 . The disc prosthesis system as in  claim 16 , wherein the at least one resilient support member is disposed within the resilient material and attached to the upper and lower curved surfaces. 
   
   
       23 . The disc prosthesis system as in  claim 16 , wherein the at least one resilient support member comprises a plurality of springs. 
   
   
       24 . The disc prosthesis system as in  claim 16 , wherein the upper and lower curved surfaces of the core comprise at least one of a polymer, a ceramic or a metal. 
   
   
       25 . The disc prosthesis system as in  claim 24 , wherein the metal comprises at least one of cobalt chrome molybdenum, titanium or stainless steel. 
   
   
       26 . A method of assembling an intervertebral prosthesis for insertion into a patient, the method comprising:
 selecting a resilient core from among a plurality of resilient cores;   placing the core between first and second supports;   wherein the resilient core is selected in response to a resiliency of the core and a patient characteristic.   
   
   
       27 . The method of  claim 26 , wherein the selected core is identified with an indicia and selected in response to the indicia and a patient characteristic. 
   
   
       28 . The method of  claim 27 , wherein the indicia comprises at least one of a color of the core, a marking on the core, a height of the core, or a width of the core. 
   
   
       29 . The method of  claim 27 , wherein the indicia of each core corresponds to a resiliency of the core and a maximum angle of inclination between the supports when the core is positioned between the supports. 
   
   
       30 . The method of  claim 26 , wherein the first and second supports articulate when the selected core is positioned between the supports. 
   
   
       31 . The method of  claim 26 , wherein the core comprises first and second components that slide relative to each other when the core is loaded. 
   
   
       32 . The method of  claim 26 , wherein the core is selected in response to a maximum angle of inclination when the core is positioned between the supports. 
   
   
       33 . A method of inserting an intervertebral prosthesis into an intervertebral space between vertebrae of a patient, the method comprising:
 compressing a shock absorbing core from an expanded profile configuration to a narrow profile configuration when the core is inserted into the intervertebral space, wherein the shock absorbing core articulates an upper support and a lower support when positioned between the upper support and the lower support.   
   
   
       34 . The method of  claim 33  wherein the upper support and the lower support are positioned in the intervertebral space, and the shock absorbing core is inserted between the upper support and the lower support while the upper support and the lower support are positioned in the intervertebral space. 
   
   
       35 . The method of  claim 34  wherein shock absorbing core locks into place within the upper plate or the lower plate. 
   
   
       36 . The method of  claim 33  wherein the core is positioned between the upper support and the lower support when the upper support and the lower support are inserted into the intervertebral space. 
   
   
       37 . The method of  claim 36  wherein the upper support and the lower support articulate when the upper support and the lower support are inserted into the intervertebral space. 
   
   
       38 . The method of  claim 33  wherein the shock absorbing core is compressed with an instrument when the core is inserted into the intervertebral space. 
   
   
       39 . The method of  claim 38  wherein the shock absorbing core is compressed by at least about 0.5 mm with the instrument when the core is inserted into the intervertebral space. 
   
   
       40 . An intervertebral disc prosthesis comprising:
 a resilient core, the core comprising,
 upper component with an upper surface and a lower component with a lower surface, and 
 at least one of a resilient material or a resilient member disposed between the upper and lower components to allow the upper and lower components to move resiliently toward and away from each other, wherein the upper and lower components define an inner chamber of the core and wherein at least one channel extends from the inner chamber to an external surface of the core to pass fluid through the chamber; and 
   upper and lower supports locatable about the core, each support comprising,
 an outer surface which engages a vertebra, and 
 an inner surface shaped to contact one of the surfaces of the core; 
   wherein the upper and lower supports are adapted to articulate when the core is positioned between the upper and lower supports.   
   
   
       41 . The prosthesis of  claim 40  wherein the at least one channel comprises at least two channels that extend from the chamber to the external surface of the core to pass fluid through the core. 
   
   
       42 . The prosthesis of  claim 40  wherein the at least one channel is adapted to pump fluid out of the core when the components move toward each other and draw fluid into the core when the components move away from each other. 
   
   
       43 . An instrument for insertion of an intervertebral disc prosthesis into an intervertebral space, the instrument comprising:
 a distractor tip comprising a channel dimensioned to pass the prosthesis; and   at least one of a resilient member or a resilient material to compress the prosthesis from an expanded profile to a narrow profile configuration with the distractor tip when the prosthesis slides along the channel toward the intervertebral space.   
   
   
       44 . The instrument of  claim 43  further comprising a pair of handles connected to the distractor tip, wherein the resilient member comprises a spring connected to the handles to drive the handles apart and compress the prosthesis to the narrow profile configuration. 
   
   
       45 . An system for insertion of an intervertebral disc prosthesis into an intervertebral space, the system:
 a plurality of selectable shock absorbing intervertebral disc prosthesis cores; and   an instrument comprising a distractor tip with a channel dimensioned to pass the prosthesis, wherein the distractor tip is capable of compressing at least one of the plurality of cores from an expanded profile configuration to a narrow profile configuration when the prosthesis slides along the channel toward the intervertebral space.   
   
   
       46 . The instrument of  claim 45  wherein the expanded profile configuration comprises an unloaded configuration of the at least one of the plurality of cores and the narrow profile configuration comprises a maximum loaded compression of the at least one of the plurality of cores.