A novel injectable bioactive bone cement for spinal surgery: A developmental and preclinical study

Abstract

The injection of bone cement by minimally invasive techniques for the treatment of vertebral body fractures or for stabilization of an osteoporotic vertebral body is regarded as promising in spinal surgery. The purpose of this study was to develop a novel injectable bioactive bone cement to address such concerns. The cement was composed mainly of strontium-containing hydroxyapatite (Sr-HA) filler and Bisphenol A Diglycidylether Dimethacrylate (D-GMA) resin. The Sr-HA filler was prepared by precipitation and calcination, then analyzed with Fourier transform infrared (FTIR) spectra and X-ray diffraction (XRD) patterns. Samples of strontium-containing hydroxyapatite cement (SrHAC) were formed by a combination of powder filler and resin matrix, with the setting time and peak temperature recorded. Cell relative growth rate (RGR), Tetrazolium bromide (MTT), and haemolysis tests were used to detect initial in vitro biocompatibility of the new cement. In vitro spinal biomechanical testing and morphological observation after bone cement injection were performed on pig spines. Results indicate that the setting time and peak temperature of the cement was 15 min and 55 degrees C, respectively. Cytotoxicity of the cement was class 1 (no cytotoxicity) and haemolysis was 1% (no haemolysis). Stiffness after cement injection and fatigue loading were 112% and 95% of the intact bone, respectively, which is similar to that of natural bone. Radiopacity of SrHAC allowed easy radiographic imaging. The use of SrHAC cement is, thus, promising in spinal surgery.

Calcium orthophosphate-based biocomposites and hybrid biomaterials

“…However, PMMA sets by a polymerization of toxic monomers, which also evolves significant amounts of heat that damages tissues. Moreover, it is neither degradable nor bioactive, it does not bond chemically to bones and might generate particulate debris leading to an inflammatory foreign body response [104,110]. A number of other non-degradable polymers applied in orthopedic surgery include PE in its different modifications such as low density PE, high-density polyethylene (HDPE), and Ultrahigh molecular weight polyethylene (used as the articular surface of total hip replacement implants [111,112]), polyethylene terepthalate, polypropylene, and PTFE, which are applied to repair knee ligaments [113].…”

“…As a result, quick setting and degradable biocomposite cements with a low-heat output and compressive strengths in the range of 1 to 12 MPa were prepared by varying the molecular weight of PPF, as well as the contents of the monomer, b-TCP, initiator, and porogen (NaCl) [453,454]. An acrylic cement with Sr-containing HA as a filler [110] and an injectable polydimethylsiloxane/HA cement [455] have been prepared as well.…”

Injectable acrylic bone cements for vertebroplasty with improved properties

“…6 In spite of the success claimed for PVP and the growing interest for this technique, there are only a few literature reports of studies dealing with injectable and radiopaque acrylic bone cement specially designed for this purpose. 7 Li et al 7 reported excellent radiopacity and injectability of an acrylic bone cement containing strontium hydroxyapatite as the radiopaque agent.…”

Development of magnesium calcium phosphate biocement for bone regeneration

“…To be suitable for use in bone defect repair, a bone cement should not only have the characteristics of rapid setting but also adequate stiffness, which confers immediate load-bearing capacity and stiffness resembling the natural bone more closely (Li et al 2000;Burguera et al 2006). Moreover, high early strength is needed to prevent early-stage implant failure or disintegration (Dorozhkin 2008).…”