26dkou59810.3205/26dkou598urn:nbn:de:0183-26dkou5985Meeting AbstractBioactive calcium sulfate/hydroxyapatite augmentation with systemic zoledronic acid for pedicle screw fixation in an osteoporotic minipig modelOberländerOberländerJan TejaJTUniversity Hospital Carl Gustav Carus, Dresden, DeutschlandauthorTianTianXingguiXUniversitätsmedizin Greifswald, Greifswald, DeutschlandauthorDischDischAlexanderAUniversity Hospital Carl Gustav Carus, Dresden, DeutschlandauthorSchaserSchaserKlaus-DieterKDUniversity Hospital Carl Gustav Carus, Dresden, DeutschlandauthorLeeLeePeterPUniversity College London, London, UKauthorChenChenJishizhanJUniversity College London, London, UKauthorLiuLiuJingwenJUniversity College London, London, UKauthorLidgrenLidgrenLarsLLund University, Lund, SchwedenauthorTägilTägilMagnusMLund University, Lund, SchwedenauthorRainaRainaDeepakDLund University, Lund, SchwedenauthorZwingenbergerZwingenbergerStefanSUniversitätsmedizin Greifswald, Greifswald, DeutschlandauthorGerman Medical Science GMS Publishing House
Düsseldorf
61020261020englThis is an Open Access article distributed under the terms of the Creative Commons Attribution 4.0 License.Dieser Artikel ist ein Open-Access-Artikel und steht unter den Lizenzbedingungen der Creative Commons Attribution 4.0 License (Namensnennung).M0659598Deutsche Gesellschaft für Orthopädie und UnfallchirurgieDeutsche Gesellschaft für Orthopädie und Orthopädische ChirurgieDeutsche Gesellschaft für UnfallchirurgieBerufsverband für Orthopädie und UnfallchirurgieDeutscher Kongress für Orthopädie und Unfallchirurgie (DKOU 2026)Poster experimentell | TraumaBerlin2026102020261023DKOU26_Abs_2420TextObjectives and questions: Pedicle screw fixation in osteoporotic bone remains biomechanically challenging (Tian et al., 2022). While PMMA cement provides immediate stability, it is bioinert and does not promote osseointegration (Tian et al., 2022). Calcium sulfate/hydroxyapatite (CaS/HA) composites represent bioactive alternatives (Tian et al., 2022), , and systemic bisphosphonates such as zoledronic acid (ZA) may further enhance peri-implant bone formation . This study investigated whether systemic ZA enhances the fixation strength of pedicle screws augmented with CaS/HA in an osteoporotic large-animal model.Material and methods: A controlled prospective in vivo animal study was conducted using eleven female Göttingen minipigs. Osteoporosis was induced via ovariectomy combined with glucocorticoid administration and a calcium-restricted diet. After 6 months, pedicle screws (4.5 × 25 mm) were inserted into five lumbar vertebrae. One side was augmented with approximately 0.5 mL CaS/HA cement, while contralateral pedicles served as non-augmented controls. Systemic ZA was administered one-week post-implantation. Specimens were harvested at 2, 6, and 12 weeks (n=3/timepoint). µCT and synchrotron CT assessed peri-implant bone structure. Bone volume fraction (BV/TV) and bone mineral density (BMD) were quantified in defined ROIs. Biomechanical fixation was evaluated by manually measured maximum extraction torque. Histology (H&E, Goldner) assessed tissue response. Statistical analysis included Shapiro-Wilk testing and paired t-tests (p<0.05).Results: µCT confirmed successful osteoporosis induction, with significantly reduced BV/TV and BMD in OVX animals compared with sham controls after 6 months (Figure 1A ). Synchrotron CT following screw removal demonstrated peri-thread bone formation. Residual bone substitute was present at the screw tips at 2 and 6 weeks but was largely resorbed by 12 weeks (Figure 1B ). Quantitative µCT revealed significantly higher peri-implant BV/TV on the augmented side compared with screw-only controls (p<0.05) (Figure 1C ). No differences were observed in manually measured maximum removal torque between groups (Figure 1D ). Histology confirmed the presence of biomaterial remnants at 6 weeks, whereas at 12 weeks, the CaS/HA was largely resorbed, with no additional new bone formation (Figure 1E ). Discussion and conclusions: Systemic ZA combined with CaS/HA augmentation increased peri-implant bone volume but did not improve biomechanical fixation in this osteoporotic minipig model. Limited bioactivation in cortical-dominant pedicles and anatomical constraints may explain the absent mechanical benefit. Further studies in models more closely reflecting human spinal anatomy and loading are required to validate the translational potential of bioactive augmentation strategies.Tian XComparison of immediate anchoring effectiveness of two different techniques of bioresorbable ceramic application for pedicle screw augmentation2024Ceramics International12877-12889Tian X, et al. Comparison of immediate anchoring effectiveness of two different techniques of bioresorbable ceramic application for pedicle screw augmentation. Ceramics International. 2024;50(8):12877-12889. DOI: 10.1016/j.ceramint.2024.01.195https://doi.org/10.1016/j.ceramint.2024.01.195Markeviciute VPuthia MArvidsson LLiu YTörnquist ETengattini AHuang JBai YVater CPetrolis RZwingenberger SKrisciukaitis ASmailys ALukosevicius SStravinskas MIsaksson HTarasevicius SLidgren LTägil MRaina DBSystemically administered zoledronic acid activates locally implanted synthetic hydroxyapatite particles enhancing peri-implant bone formation: A regenerative medicine approach to improve fracture fixation2024Acta Biomater354-370Markeviciute V, Puthia M, Arvidsson L, Liu Y, Törnquist E, Tengattini A, Huang J, Bai Y, Vater C, Petrolis R, Zwingenberger S, Krisciukaitis A, Smailys A, Lukosevicius S, Stravinskas M, Isaksson H, Tarasevicius S, Lidgren L, Tägil M, Raina DB. Systemically administered zoledronic acid activates locally implanted synthetic hydroxyapatite particles enhancing peri-implant bone formation: A regenerative medicine approach to improve fracture fixation. Acta Biomater. 2024 Apr 15;179:354-370. DOI: 10.1016/j.actbio.2024.03.005https://doi.org/10.1016/j.actbio.2024.03.005011
Figure 1: Imaging, biomechanical, and histological evaluation of pedicle screw augmentation.