Spinal Fusion of an Unstable Atlantoaxial Fracture in a Completely Tetraplegic Patient Using Silicate-Substituted Calcium Phosphate

Abstract

Bone graft harvesting from the iliac crest constitutes the gold standard in spinal surgery due to its osteogenic, osteoconductive and osteoinductive properties. Large amounts of autograft can provoke complications like donor site morbidity, pain and the need for a second operation. Therefore, research into bone graft substitutes is of great interest. Silicate-substituted calcium phosphate (Actifuse(TM) Synthetic Bone Graft, ApaTech Ltd, London) was used in combination with morselized corticocancellous graft in a transarticular stabilization (modified Magerl) of a completely tetraplegic patient with an unstable atlantoaxial fracture. Computed tomography showed bone bridging between the segment C1/C2, the surface of the implant and the remodeled bone at follow-up at 8 months. The use of silicate-substituted calcium phosphate as a bone graft extender in spinal surgery could be an alternative to autografting from the iliac crest. Vegetative symptoms are often underestimated but can be triggered by donor site morbidity or pain in patients after spinal cord injury.

Silicon-substituted calcium phosphate promotes osteogenic-angiogenic coupling by activating the TLR4/PI3K/AKT signaling axis

“…Kirschner et al 2 used Si-CaP for the treatment of benign bone defects in children, and confirmed its good therapeutic effect by clinical and radiological follow-up. Coincidentally, Putz et al 3 also used Si-CaP in the treatment of a transarticular stabilization (modified Magerl) of a completely tetraplegic patient with an unstable atlantoaxial fracture, and the follow-up results at 8 months showed that Si-CaP could be used as an alternative to iliac autograft in spinal surgery. In addition, Hutchens et al 4 implanted Si-CaP into a severe distal femoral defect model in sheep and observed excellent biocompatibility and bone healing in all experimental groups, which was consistent with the results of the above two clinical studies.…”

Design and clinical application of injectable hydrogels for musculoskeletal therapy

“…143 Baxter Actifuse ® Flow has successfully been used for spinal fusion procedure. 144 When used in a comparative clinical study to the Medtronic Infuse ® graft, they were able to demonstrate similar fusion rates (Actifuse ® 9/9, Infuse ® 8/9 cases) and both products yielded similar alleviation of pain and improved quality of life. 145 Also, DBM solutions have been approved clinically for spinal application.…”

“…However, effective hydrogel therapies are emerging that do not depend on BMP‐based growth factors to obtain their therapeutic effect. The before mentioned Baxter Actifuse® Flow has successfully been used for spinal fusion procedure 144 . When used in a comparative clinical study to the Medtronic Infuse® graft, they were able to demonstrate similar fusion rates (Actifuse® 9/9, Infuse® 8/9 cases) and both products yielded similar alleviation of pain and improved quality of life 145 .…”