Injectable, Solvent Free Strontium Carbonate Poly(Allyl Glycidyl Ether Succinate) Composite Networks for Vertebral Augmentation

Vertebral body compression fractures are a major cause of chronic back pain, particularly in older adults. Augmentation is currently performed by injecting a poly(methyl methacrylate) (PMMA) slurry of polymer, monomer, and initiator mixed with barium sulfate (BaSO₄) into the vertebrae, which then polymerizes in vivo. Herein, a solvent-free polymer system using poly(allyl glycidyl ether succinate) (PAGES) is developed for vertebral augmentation. PAGES crosslinks in situ through thiol-ene click chemistry with a cure time at 37 °C ranging from 17 to 53 min based on degree of polymerization and crosslinker concentration. The addition of SrCO₃ increased the ultimate compressive strength (σ_max) of the PAGES composite to 4.4 ± 0.4 MPa. Furthermore, SrCO₃ increases osteoblast proliferation and differentiation of mesenchymal stem cells seeded onto the surface of PAGES composite. Finally, the compressive strength of fractured vertebrae is increased in an ex vivo surrogate rabbit model when filled with injected PAGES composite, demonstrating its potential as a bone augmentation material.