Minimally invasive injectable lumbar interbody fusion with mineralized collagen-modified PMMA bone cement: A new animal model

Abstract

This study was to develop a feasible and safe animal model for minimally invasive injectable lumbar interbody fusion using a novel biomaterial, mineralized collagen-polymethylmethacrylate bone cement (MC-PMMA), with unilateral pedicle screw fixation in an in vivo goat model. Eight goats ( Capra aegagrus hircus) were divided into three groups: MC-PMMA, unmodified commercial-polymethylmethacrylate bone cement (UC-PMMA), and a control group (titanium cage filled with autogenous bone, TC-AB). Each group of goats was treated with minimally invasive lumbar interbody fusion at the L3/L4 and L5/L6 disc spaces (injected for MC-PMMA and UC-PMMA, implanted for TC-AB). The pedicle screws were inserted at the L3, L4, L5, and L6 vertebrae, respectively, and fixed on the left side. The characteristics of osteogenesis and bone growth were assessed at the third and the sixth month, respectively. The methods of evaluation included the survival of each animal, X-ray imaging, and 256-layer spiral computed tomography (256-CT) scanning, imaged with three-dimensional microfocus computed tomography (micro-CT), and histological analysis. The results showed that PMMA bone cement can be extruded smoothly after doping MC, the MC-PMMA integrates better with bone than the UC-PMMA, and all goats recovered after surgery without nerve damage. After 3 and 6 months, the implants were stable. New trabecular bone was observed in the TC-AB group. In the UC-PMMA group a thick fibrous capsule had formed around the implants. The MC-PMMA was observed to have perfect osteogenesis and bone ingrowth to adjacent bone surface. Minimally invasive injectable lumbar interbody fusion using MC-PMMA bone cement was shown to have profound clinical value, and the MC-PMMA showed potential application prospects.

Bioactive mineralized small intestinal submucosa acellular matrix/PMMA bone cement for vertebral bone regeneration

“…Instead, PMMA bone cement may be encapsulated by fibrous tissue. Furthermore, the low attachment strength between the bone cement and surrounding bone [ 46 ] can cause slight movement of the cement [ 47 ], resulting in the formation of small particles or even dislodgment of the cement [ 48 ]. In contrast, bioactive bone cement has been shown to have excellent osseointegrative properties [ 49 ].…”

Advances in osseointegration of biomimetic mineralized collagen and inorganic metal elements of natural bone for bone repair

“…The results showed that the circumferential contact index between MC-PMMA and bone was 36.4% higher, and histological staining revealed that the surface of MC-PMMA was in direct contact with new bone, while PMMA was encapsulated by fibrous tissue. Kong et al [ 100 ] developed a minimally invasive injectable lumbar interbody fusion goat model using MC-PMMA. The osteogenic potential of MC-PMMA, PMMA and titanium cage filled with autogenous bone (TC-AB) was compared at 3 and 6 months after surgery.…”

Biomaterials for Interbody Fusion in Bone Tissue Engineering

“…It was found that PMMA bone cement showed a good osteogenic ability in a sheep model, but this finding needs to be verified in further clinical transformational experiments. Minimally invasive injectable lumbar interbody fusion with mineralized collagen–PMMA bone cement has far-reaching clinical value and shows potential application prospects ( Kong et al, 2020 ). However, not all allogeneic fillers are conducive to fusion.…”