Biphasic calcium phosphate with submicron surface topography in an Ovine model of instrumented posterolateral spinal fusion. Issue 4 (28th November 2018)

• Record Type: Journal Article
• Authors: van Dijk, Lukas A.; Duan, Rongquan; Luo, Xiaoman; Barbieri, Davide; Pelletier, Matthew; Christou, Chris; Rosenberg, Antoine J. W. P.; Yuan, Huipin; Barrèrre‐de Groot, Florence; Walsh, William R.; de Bruijn, Joost D.
• Is Part Of: JOR spine. Volume 1:Issue 4(2018)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2018-11-28
• Subjects: biphasic calcium phosphate -- posterolateral spinal fusion -- sheep -- submicron -- surface topography; Spine -- Diseases -- Periodicals; Spine -- Diseases -- Treatment -- Periodicals; Spine -- Wounds and injuries -- Periodicals; Orthopedics -- Periodicals; Electronic journal; Periodicals; 616.73005
• DOI: 10.1002/jsp2.1039
• Languages: English
• ISSNs: 2572-1143

Abstract

Abstract : As spinal fusions require large volumes of bone graft, different bone graft substitutes are being investigated as alternatives. A subclass of calcium phosphate materials with submicron surface topography has been shown to be a highly effective bone graft substitute. In this work, a commercially available biphasic calcium phosphate (BCP) with submicron surface topography (MagnetOs; Kuros Biosciences BV) was evaluated in an Ovine model of instrumented posterolateral fusion. The material was implanted stand‐alone, either as granules (BCPgranules ) or as granules embedded within a fast‐resorbing polymeric carrier (BCPputty ) and compared to autograft bone (AG). Twenty‐five adult, female Merino sheep underwent posterolateral fusion at L2‐3 and L4‐5 levels with instrumentation. After 6, 12, and 26 weeks, outcomes were evaluated by manual palpation, range of motion (ROM) testing, micro‐computed tomography, histology and histomorphometry. Fusion assessment by manual palpation 12 weeks after implantation revealed 100% fusion rates in all treatment groups. The three treatment groups showed a significant decrease in lateral bending at the fusion levels at 12 weeks ( P < 0.05) and 26 weeks ( P < 0.001) compared to the 6 week time‐point. Flexion‐extension and axial rotation were also reduced over time, but statistical significance was only reached in flexion‐extension for AG and BCPputty between the 6 and 26 week time‐points ( P < 0.05). No significant differences in ROM were observed between the treatment groups at any of the time‐points investigated. Histological assessment at 12 weeks showed fusion rates of 75%, 92%, and 83% for AG, BCPgranules and BCPputty, respectively. The fusion rates were further increased 26 weeks postimplantation. Similar trends of bone growth were observed by histomorphometry. The fusion mass consisted of at least 55% bone for all treatment groups 26 weeks after implantation. These results suggest that this BCP with submicron surface topography, in granules or putty form, is a promising alternative to autograft for spinal fusion. Abstract : This publication describes the successful use of an advanced calcium phosphate bone graft with submicron surface topography in a clinically relevant Ovine model of instrumented posterolateral spinal fusion. The graft material was implanted standalone, as granules or granules embedded within a fast‐resorbing polymeric carrier, with autograft bone as reference treatment. After 6, 12 and 26 weeks, outcomes were evaluated by manual palpation, range of motion testing, micro‐computed tomography, histology and histomorphometry. The results revealed high fusion rates after 12 weeks for both BCP treatments, with overall equivalence to autograft in fusion rate, mechanical integrity and bone formation over the entire healing period of 26 weeks.