Engineered Scaffolds for Intervertebral Disc Repair and Regeneration and for Articulating Joint Repair and Regeneration

Abstract

Methods for the engineering and preparation of intervertebral disc repair scaffolds and articulating joint repair scaffolds are disclosed. The methodology utilizes either magnetic resonance images or combined magnetic resonance and computed tomography images as a template for creating either the intervertebral scaffold or the joint repair scaffold (e.g., osteochondral scaffold) with fixation to the underlying bone. The disc scaffold design may include an outer annulus that may contain desired structures and a central nucleus pulposus region that could either contain a designed microstructure or a contained hydrogel. The osteochondral scaffold may include a bone compartment interface with a cartilage compartment. The bone compartment may interface with a cutout portion of the bone through fixation components. Different microstructure designs may be created for the bone and cartilage compartment to represent desired mechanical and mass transport properties. The microstructure controls elastic and permeability property distribution within the scaffold.

1 . An intervertebral disc repair and/or regeneration scaffold comprising:
 a central core shaped to approximate the nucleus pulposus of a natural intervertebral disc, the central core having a first porous microstructure; and   an outer annulus shaped to approximate the annulus fibrosus of a natural intervertebral disc, the outer annulus connected to and surrounding the central core, the outer annulus having a second porous microstructure,   wherein the central core and the outer annulus have different permeability.   
     
     
         2 . The scaffold of  claim 1 , wherein the central core and the outer annulus have different elasticity. 
     
     
         3 . The scaffold of  claim 1 , wherein the central core includes a bioactive agent. 
     
     
         4 . The scaffold of  claim 3 , wherein the bioactive agent is selected from undifferentiated chondrocyte precursor cells from periosteum, mesenchymal stem cells from bone marrow, chondrocytes, sclerosing agents, angiogenesis activators, angiogenesis inhibitors, and mixtures thereof. 
     
     
         5 . The scaffold of  claim 1 , wherein the scaffold is formed from a biodegradable polymer. 
     
     
         6 . The scaffold of  claim 1 , wherein the central core includes a biocompatible material. 
     
     
         7 . The scaffold of  claim 1 , wherein the central core includes a hydrogel. 
     
     
         8 . The scaffold of  claim 1 , wherein the central core comprises wavy fibers. 
     
     
         9 . The scaffold of  claim 1 , wherein the scaffold is formed from a material selected from biodegradable polymers, biodegradable ceramics, non-biodegradable metals, non-biodegradable metal alloys, or mixtures thereof. 
     
     
         10 . The scaffold of  claim 1 , further comprising at least one marking including a tracer that provides enhanced visibility via a medical imaging device. 
     
     
         11 . The scaffold of  claim 1 , further comprising at least one radiopaque marking that provides enhanced visibility via a fluoroscope. 
     
     
         12 . The scaffold of  claim 1 , wherein the scaffold includes a region of no material or radiolucent material such that the region forms an imaging window for enhanced visibility through the imaging window via a medical imaging device. 
     
     
         13 . The scaffold of  claim 1 , wherein the scaffold includes at least one marking for alignment during implantation. 
     
     
         14 . The scaffold of  claim 1 , further comprising an osteoconductive mineral coating on at least a portion of the scaffold. 
     
     
         15 . The scaffold of  claim 14 , wherein the osteoconductive mineral coating comprises a plurality of discrete mineral islands. 
     
     
         16 . The scaffold of  claim 14 , wherein the osteoconductive mineral coating comprises a substantially homogeneous mineral coating. 
     
     
         17 . The scaffold of  claim 14 , wherein the osteoconductive mineral coating comprises a calcium compound. 
     
     
         18 . The scaffold of  claim 14 , wherein the osteoconductive mineral coating comprises hydroxyapatite, calcium-deficient carbonate-containing hydroxyapatite, tricalcium phosphate, octacalcium phosphate, dicalcium phosphate, calcium phosphate, and mixtures thereof. 
     
     
         19 . The scaffold of  claim 14 , wherein a bioactive agent is associated with the mineral coating. 
     
     
         20 . The scaffold of  claim 14 , wherein the bioactive agent is selected from bone morphogenetic proteins.