Research progress on the biological modifications of implant materials in 3D printed intervertebral fusion cages

Abstract

Anterior spine decompression and reconstruction with bone grafts and fusion is a routine spinal surgery. The intervertebral fusion cage can maintain intervertebral height and provide a bone graft window. Titanium fusion cages are the most widely used metal material in spinal clinical applications. However, there is a certain incidence of complications in clinical follow-ups, such as pseudoarticulation formation and implant displacement due to nonfusion of bone grafts in the cage. With the deepening research on metal materials, the properties of these materials have been developed from being biologically inert to having biological activity and biological functionalization, promoting adhesion, cell differentiation, and bone fusion. In addition, 3D printing, thin-film, active biological material, and 4D bioprinting technology are also being used in the biofunctionalization and intelligent advanced manufacturing processes of implant devices in the spine. This review focuses on the biofunctionalization of implant materials in 3D printed intervertebral fusion cages. The surface modifications of implant materials in metal endoscopy, material biocompatibility, and bioactive functionalizationare summarized. Furthermore, the prospects and challenges of the biofunctionalization of implant materials in spinal surgery are discussed.

Comparison of radiological and clinical outcomes of 3D-printed artificial vertebral body with Titanium mesh cage in single-level anterior cervical corpectomy and fusion: A meta-analysis

“…Anterior cervical corpectomy and fusion(ACCF) is a common surgical method to treat cervical-related diseases ( 5 , 10 ), Spinal surgeons are always looking for a more efficient and more secure implants and Titanium Mesh Cage(TMC) has gradually replaced autologous bone graft and become mainstream ( 15 , 27 , 28 ), the emergence of Three-dimensional printing technology provides a brand-new choice of fusion implant ( 29 ), However, at present, there is no large-scale research to prove whether 3D printed artificial vertebral body is more safe and effective than traditional TMC. In this paper, six cohort studies were included to analyze the efficacy and safety of 3D-printed artificial vertebral body in single-level anterior cervical corpectomy and fusion(SL-ACCF), and the results show that 3D printing artificial vertebral body is superior to traditional TMC in shortening the operation time, reducing the occurrence of Severe subsidence of vertebral body and restoring C2–C7 Cobb Angle, but there is no significant difference in Japanese Orthopedic Association (JOA) scores, Visual Analog Scale (VAS) scores and reducing intraoperative blood loss.…”

“…Funnel plot of preoperative cervical C2-C7 Cobb angle, Visual Analog Scale (VAS) scores, Japanese Orthopedic Association (JOA) scores. brand-new choice of fusion implant (29), However, at present, there is no large-scale research to prove whether 3D printed artificial vertebral body is more safe and effective than traditional TMC. In this paper, six cohort studies were included to analyze the efficacy and safety of 3D-printed artificial vertebral body in single-level anterior cervical corpectomy and fusion(SL-ACCF), and the results…”

Bioactive surface modifications through thermally sprayed hydroxyapatite composite coatings: a review of selective reinforcements

“…Recently, Sun et al 235 investigated the surface modifications of 3D printed scaffolds by the plasma spray process, which resulted in a smooth and continuous surface, thus promoting mesenchymal stem cells proliferation in vitro and bone repairability in vivo . A very recent review by Li et al 434 highlighted that 3D and 4D bioprinted implants were facing challenges in the bioactive functionalization of surfaces. Thus, it would be an opportunity for future researchers to enhance surface properties and offer bioactive surface modifications through thermally sprayed HA composite coatings.…”

Biomechanical performance of the novel assembled uncovertebral joint fusion cage in single-level anterior cervical discectomy and fusion: A finite element analysis

“…We printed the bone graft material or artificially filled and compacted it into the bone graft area before surgery, eliminating the need to implant decompressed bone or artificial bone particles into the uncovertebral joint fusion area through surgical forceps, thus reducing the risk of complications caused by dislodged bone graft particles, shortening surgery time, and making the operation easier. In addition, because of the split design, we could use 3D printing technology to individually print the intervertebral support body and the uncovertebral joint fusion components in reference to previous studies which focused on 3D-printed discs or fusion devices ( Serra et al, 2016 ; Basgul et al, 2020 ; Li et al, 2021 ; Zhu et al, 2021 ) to achieve a good fit between the intervertebral support body, the uncovertebral joint fusion components, and the patient’s vertebral space, thereby reducing the difficulty of surgical operation and improving the prosthesis–end plate fit.…”