Microcomputed tomographic, biomechanical and histological analyses of lumbar interbody fusion with iliac crest bone graft in a pig model

Krtička, Milan; Nekuda, Vladimír; Ira, Daniel; Sedláček, Radek; Suchý, Tomáš; Kavková, Michaela; Břínek, Adam; Göpfrt, Eduard; Bilik, Andrej; Kaiser, Jozef; Křen, Leoš; Plánka, Ladislav

doi:10.2754/avb202190010069

Acta Veterinaria > Archive > 2021, Vol. 90 > Issue 1 > Microcomputed tomographic, biomechanical…

Acta Vet. Brno 2021, 90: 69-75

https://doi.org/10.2754/avb202190010069

Microcomputed tomographic, biomechanical and histological analyses of lumbar interbody fusion with iliac crest bone graft in a pig model

Milan Krtička¹, Vladimír Nekuda¹, Daniel Ira¹, Radek Sedláček², Tomáš Suchý³, Michaela Kavková⁴, Adam Břínek⁴, Eduard Göpfrt⁵, Andrej Bilik¹, Jozef Kaiser⁴, Leoš Křen⁶, Ladislav Plánka⁷

¹Masaryk University and The University Hospital Brno, Faculty of Medicine, Trauma Surgery Department, Brno, Czech Republic
²Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Mechanics, Biomechanics and Mechatronics, Prague, Czech Republic
³The Czech Academy of Sciences, Institute of Rock Structure and Mechanics, Department of Composites and Carbon Materials, Prague, Czech Republic
⁴Brno University of Technology, Central European Institute of Technology, Brno, Czech Republic
⁵Veterinary Research Institute, Brno, Czech Republic
⁶Masaryk University and The University Hospital Brno, Faculty of Medicine, Department of Pathology, Brno, Czech Republic
⁷Masaryk University and The University Hospital Brno, Faculty of Medicine, Department of Pediatric Surgery, Orthopaedics and Traumatology, Brno, Czech Republic

Received November 30, 2020
Accepted February 24, 2021

The main goal of this study was to assess the progress of vertebral stability after lumbar interbody fusion related to microcomputed tomography (micro CT), biomechanical analysis, and histological assessment towards spine fusion. Twelve male pigs were used; each underwent L2-3 discectomy and implantation of an iliac crest bone graft in two groups; six spines were harvested eight weeks (A1) and six spines 16 weeks (A2) after surgery (7 native spines for biomechanical analysis). The CT was performed by GE phoenix datos|x 2.0 with a sample drift correction. The samples were divided according to fusion quality. Biomechanical evaluation was carried out on the MTS Mini Bionix testing system. In the nondestructive mode, three cycles of pure bending moments were applied (5 Nm load limit) at a rate of 20 °/min in flexion (+40 °) and extension (-40 °). Two representative histological sections from four samples were obtained (A1, n = 2; A2, n = 2); areas of mature bone were quantified. In micro CT, better results were achieved in group A2 (not significant). Eight weeks after the operation, flexural stiffness decreased to 48% of its initial value for native cadavers (P < 0.05); after 16 weeks it was comparable to native cadavers, demonstrating the suitability of the implanted graft (P < 0.05). The newly formed bone tissue occupied an average area of 94.205 mm² (A1) and 26.240 mm² (A2). It was confirmed that micro CT, biomechanical analysis, and histological assessment are technically feasible and suitable for the evaluation of results of other methods of large bone defect treatment.

Keywords

Bone replacement, spine, injury.

Funding

This project was funded by Czech health research council of the Ministry of Health of the Czech Republic, Project AZV 17-31276 and MH CZ - DRO (FNBr, 65269705).