Experimental vertebroplasty using osteoconductive granular material.
METHODS
Osteoporotic human cadaveric thoracic vertebral bodies and vertebral bodies from mature sheep were used as model systems to assess coral resorption and new bone formation after injection of coral granules.


OBJECTIVE
To evaluate the use of natural coral exoskeleton, an osteoconductive material, for the filling of vertebral bodies.


BACKGROUND
Percutaneous injection of polymethylmetacrylate (PMMA) is often proposed for prophylactically stabilizing osteoporotic vertebral bodies at risk for fracture or augmentation of vertebral bodies that have already fractured. Recently, the possibility of using osteoconductive materials in granular formulation was assessed in pilot studies.


METHODS
As a first step, the possibility of injecting coral granules percutaneously within osteoporotic human cadaveric thoracic vertebral bodies was assessed. As a second step, cavities were drilled into vertebral bodies of 10 mature ewes and were either left empty (control group) or filled with coral alone (CC) or coral supplemented with fibrin sealant (CC+FS). Quantitative evaluation of coral resorption and new bone formation was made 2 months and 4 months after implantation.


RESULTS
The distribution of coral granules injected into human cadaveric thoracic vertebral bodies was homogenous as assayed radiographically. In the experimental animal model, osteogenesis was increased in cavities filled with coral in comparison with cavities left empty at both 2 months and 4 months (P < 0.005 and P < 0.02, respectively). Surprisingly, supplementation of coral with a fibrin sealant had no positive influence on osteogenesis (P < 0.0008 at 2 months; P < 0.002 at 4 months). In addition, it led to an increase in coral resorption by as soon as 2 months (P < 0.0008).


CONCLUSIONS
These results demonstrate the osteoconductivity of coral in granular form for vertebral filling. Interestingly, interconnectivity between adjacent bone trabeculae and newly formed bone was restored; however, its mechanical significance remains to be determined. Further investigations are needed to evaluate the efficacy of coral in osteopenic animals and in relieving pain.
Cunin
G
G
Centre de traitement de la douleur, hôpital Lariboisière, the Service de neuro-chirurgie, Fondation Rothschild, and the Laboratoire de Recherches Orthopédiques Université Diderot ParisVII, Paris, France.
Boissonnet
H
H
Petite
H
H
Blanchat
C
C
Guillemin
G
G
D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D001861:Bone Regeneration; D002119:Calcium Carbonate / Q000627:therapeutic use*; D003063:Cnidaria; D004359:Drug Therapy, Combination; D005260:Female; D015718:Fibrin Tissue Adhesive / Q000627:therapeutic use*; D006801:Humans; D010024:Osteoporosis / Q000000981:diagnostic imaging / Q000601:surgery*; D011859:Radiography; D012756:Sheep; D013122:Spinal Diseases / Q000000981:diagnostic imaging / Q000601:surgery*; D013904:Thoracic Vertebrae / Q000000981:diagnostic imaging / Q000601:surgery*; D014014:Tissue Adhesives / Q000627:therapeutic use*
D015718:Fibrin Tissue Adhesive; D014014:Tissue Adhesives; D002119:Calcium Carbonate