AO Spine Guideline for Using Osteobiologics in Spine Degeneration project is an international collaborative initiative to identify and evaluate evidence on existing use of osteobiologics in spine degenerative diseases. It aims to formulate clinically relevant and internationally applicable guidelines ensuring evidence-based, safe and effective use of osteobiologics. The current focus is the use of osteobiologics in anterior cervical discectomy and fusion surgeries. The guideline development is planned in three phases. Phase 1- Evidence synthesis and Recommendation; Phase 2- Guideline with osteobiologics grading and Validation; Phase 3- Guideline dissemination and Development of a clinical decision support tool. The key questions formulating the guidelines for the use of osteobiologics will be addressed in a series of systematic reviews in Phase 1. The evidence synthesized by the systematic reviews will be assessed by Grading of Recommendations, Assessment, Development and Evaluations (GRADE) methodology, including expert panel discussions to formulate a recommendation. In Phase 2, osteobiologics will be graded based on evidence and the grading will be integrated with the recommendation from Phase 1, and thus formulate a guideline. The guideline will be further validated by prospective clinical studies. In the third phase, dissemination of the proposed guideline and development of a decision support tool is planned. AO-GO aims to bridge an important gap between quality of evidence and use of osteobiologics in spine fusion surgeries. With a holistic approach the guideline aims to facilitate evidence-based, patient-oriented decision-making process in clinical practice, thus stimulating further evidence-based studies regarding osteobiologics usage in spine surgeries

Complications after spinal fusion surgery are common, with implant loosening occurring in up to 50% of osteoporotic patients. Pedicle screw fixation strength reduces as a result of decreased trabecular bone density, whereas sublaminar wiring is less affected by these changes. Therefore, pedicle screw augmentation with radiopaque sublaminar wires (made with Dyneema Purity® Radiapque fibers, DSM Biomedical, Geleen, the Netherlands) may improve fixation strength. Furthermore, sublaminar tape could result in a gradual motion transition to distribute stress over multiple levels and thereby reduce implant loosening. The objective of this study is to test this hypothesis in a novel experimental setup in which a cantilever bending moment is applied to individual human vertebrae. Thirty-eight human cadaver vertebrae were stratified into four different groups: ultra-high molecular weight polyethylene sublaminar tape (ST), pedicle screw (PS), metal sublaminar wire (SW) and pedicle screw reinforced with sublaminar tape (PS+ST). The vertebrae were individually embedded in resin, and a cantilever bending moment was applied bilaterally through the spinal rods using a universal material testing machine. This cantilever bending setup closely resembles the loading of fixators at transitional levels of spinal instrumentation. The pull-out strength of the ST (3563 ± 476N) was not significantly different compared to PS, SW or PS+ST. The PS+ST group had a significantly higher pull-out strength (4522 ± 826N) compared to PS (2678 ± 292N) as well as SW (2931 ± 250N). The higher failure strength of PS + ST compared to PS indicates that PS augmentation with ST may be an effective measure to reduce the incidence of screw pullout, even in osteoporotic vertebrae. Moreover, the lower stiffness of sublaminar fixation techniques and the absence of damage to the cortices in the ST group suggest that ST as a stand-alone fixation technique in adult spinal deformity surgery may also be clinically feasible and offer clinical benefits

Recent studies have shown that random disorder nanotopography increases osteoblast differentiation and bone formation. This has great potential merit in producing surfaces where osteointegration is required such as spinal fusion surgery and arthroplasty. However, the long-term failure of orthopaedic implants is often related to osteoclast mediated osteolysis and loosening. It is vitally important that we understand the effect of nanotopography on osteoclast formation and bone remodeling. We developed an unique osteoblast/osteoclast co-culture system derived from human mesenchymal and haematopoetic stem cells. This was co-cultured on both nanopatterned and unpatterned polycarbonate substrates. We assessed the co-culture using electron microscopy (SEM), protein expression using immunofluorescence and histochemical staining and gene expression using polymerase chain reaction (PCR). Co-culture of both osteoclasts and osteoblasts was confirmed with mature bone nodules and resorption pits identified on both surfaces. Significantly increased osteoblast differentiation and bone formation was noted on disordered nanotopography. Antagonistic genes controlling osteoclast activity were both upregulated with no significant difference in osteoclast marker gene expression. Our results confirm successful co-culture of osteoblasts and osteoclasts using an unique method closely resembling the in vivo environment encountered by orthopaedic implants. Nanotopography increases osteoblast differentiation and bone formation as previously identified, with possible subsequent increase in osteoclast mediated bone turnover

Introduction. Recently various type of spinal instrumentation was applied, and they are essential in modern spinal fusion surgery. Whereas several authors reported increased possibility of complication and degeneration on adjacent segment. We tried PLIF without instrumentation with box type intervertebral cages. Method. Forty-one cases of degenerative lumbar diseases were treated by PLIF with carbon cages without spinal instrumentation. There were 17 males and 24 females, and age averaged 71.4 years. Thirty-two cases were degenerative spondylolisthesis, five were spinal stenosis, and four were disc herniation. Single PLIF was performed on forty cases, and double segment in one, with additional decompression on other segment in twenty. Bilateral facet joint were preserved to avoid lateral instability. Two pieces of cage were inserted with local bone graft. Post-op. follow-up period were 12 to 24 months, 15 months on average. Result. JOA score (29 pts on full mark) averaged 12.7 pts before the operation and was 25.4 pts at the F/U. Recovery ratio averaged 77.9%. Clinical result was excellent in 27 with more than 75% of R/R. One case showed symptomatic non-union, and additional instrumentation was applied after one year. Thirty-three cases (80%) showed solid bone union after one year, and eight cases were classified as non-union. Whereas early cage migration with vertebral collapse was seen on fourteen, and union with collapse was seen in eight. These conditions showed less clinical outcome. Conclusion. Stand alone PLIF resulted in good clinical results with box type cages. Stand alone PLIF is less invasive method and minimize chance of complication. Conflicts of interest. None. Sources of funding. None

Objectives

Interleukin 18 (IL-18) is a regulatory cytokine that degrades the disc matrix. Bone morphogenetic protein-2 (BMP-2) stimulates synthesis of the disc extracellular matrix. However, the combined effects of BMP-2 and IL-18 on human intervertebral disc degeneration have not previously been reported. The aim of this study was to investigate the effects of the anabolic cytokine BMP-2 and the catabolic cytokine IL-18 on human nucleus pulposus (NP) and annulus fibrosus (AF) cells and, therefore, to identify potential therapeutic and clinical benefits of recombinant human (rh)BMP-2 in intervertebral disc degeneration.