scholarly journals Can activated titanium interbody cages accelerate or enhance spinal fusion? a review of the literature and a design for clinical trials

Author(s):  
Nathaniel Toop ◽  
Connor Gifford ◽  
Rouzbeh Motiei-Langroudi ◽  
Arghavan Farzadi ◽  
Daniel Boulter ◽  
...  

AbstractWhile spinal interbody cage options have proliferated in the past decade, relatively little work has been done to explore the comparative potential of biomaterial technologies in promoting stable fusion. Innovations such as micro-etching and nano-architectural designs have shown purported benefits in in vitro studies, but lack clinical data describing their optimal implementation. Here, we critically assess the pre-clinical data supportive of various commercially available interbody cage biomaterial, topographical, and structural designs. We describe in detail the osteointegrative and osteoconductive benefits conferred by these modifications with a focus on polyetheretherketone (PEEK) and titanium (Ti) interbody implants. Further, we describe the rationale and design for two randomized controlled trials, which aim to address the paucity of clinical data available by comparing interbody fusion outcomes between either PEEK or activated Ti lumbar interbody cages. Utilizing dual-energy computed tomography (DECT), these studies will evaluate the relative implant-bone integration and fusion rates achieved by either micro-etched Ti or standard PEEK interbody devices. Taken together, greater understanding of the relative osseointegration profile at the implant–bone interface of cages with distinct topographies will be crucial in guiding the rational design of further studies and innovations.

2021 ◽  
pp. 1-9

OBJECTIVE Low fusion rates and cage subsidence are limitations of lumbar fixation with stand-alone interbody cages. Various approaches to interbody cage placement exist, yet the need for supplemental posterior fixation is not clear from clinical studies. Therefore, as prospective clinical studies are lacking, a comparison of segmental kinematics, cage properties, and load sharing on vertebral endplates is needed. This laboratory investigation evaluates the mechanical stability and biomechanical properties of various interbody fixation techniques by performing cadaveric and finite element (FE) modeling studies. METHODS An in vitro experiment using 7 fresh-frozen human cadavers was designed to test intact spines with 1) stand-alone lateral interbody cage constructs (lateral interbody fusion, LIF) and 2) LIF supplemented with posterior pedicle screw-rod fixation (360° constructs). FE and kinematic data were used to validate a ligamentous FE model of the lumbopelvic spine. The validated model was then used to evaluate the stability of stand-alone LIF, transforaminal lumbar interbody fusion (TLIF), and anterior lumbar interbody fusion (ALIF) cages with and without supplemental posterior fixation at the L4–5 level. The FE models of intact and instrumented cases were subjected to a 400-N compressive preload followed by an 8-Nm bending moment to simulate physiological flexion, extension, bending, and axial rotation. Segmental kinematics and load sharing at the inferior endplate were compared. RESULTS The FE kinematic predictions were consistent with cadaveric data. The range of motion (ROM) in LIF was significantly lower than intact spines for both stand-alone and 360° constructs. The calculated reduction in motion with respect to intact spines for stand-alone constructs ranged from 43% to 66% for TLIF, 67%–82% for LIF, and 69%–86% for ALIF in flexion, extension, lateral bending, and axial rotation. In flexion and extension, the maximum reduction in motion was 70% for ALIF versus 81% in LIF for stand-alone cases. When supplemented with posterior fixation, the corresponding reduction in ROM was 76%–87% for TLIF, 86%–91% for LIF, and 90%–92% for ALIF. The addition of posterior instrumentation resulted in a significant reduction in peak stress at the superior endplate of the inferior segment in all scenarios. CONCLUSIONS Stand-alone ALIF and LIF cages are most effective in providing stability in lateral bending and axial rotation and less so in flexion and extension. Supplemental posterior instrumentation improves stability for all interbody techniques. Comparative clinical data are needed to further define the indications for stand-alone cages in lumbar fusion surgery.


2017 ◽  
Vol 18 (3) ◽  
pp. 191-194 ◽  
Author(s):  
Slobodan Novokmet ◽  
Isidora Stojic ◽  
Katarina Radonjic ◽  
Maja Savic ◽  
Jovana Jeremic

Abstract Discovery of the metallopharmaceutical cisplatin and its use in antitumour therapy has initiated the rational design and screening of metal-based anticancer agents as potential chemotherapeutics. In addition to the achievements of cisplatin and its therapeutic analogues, there are significant drawbacks to its use: resistance and toxicity. Over the past four decades, numerous transition metal complexes have been synthesized and investigated in vitro and in vivo. The most studied metals among these complexes are platinum and ruthenium. The key features of these investigations is to find novel metal complexes that could potentially exert less toxicity and equal or higher antitumour potency and to overcome other pharmacological deficiencies. Ru complexes have a different mode of action than cisplatin does, some of which are under clinical trials for treating metastatic or cisplatin-resistant tumours. This review consists of the current knowledge, published and unpublished, related to the toxicity of metallopharmaceuticals, and special attention is given to platinum [Pt(II) and Pt(IV)] and ruthenium [Ru(II) and Ru(III)] complexes.


Antibiotics ◽  
2019 ◽  
Vol 8 (2) ◽  
pp. 38 ◽  
Author(s):  
Federico Perez ◽  
Nadim G. El Chakhtoura ◽  
Mohamad Yasmin ◽  
Robert A. Bonomo

Polymyxins have been a mainstay for the treatment of extensively drug resistant (XDR) Gram-negative bacteria for the past two decades. Many questions regarding the clinical use of polymyxins have been answered, but whether the administration of polymyxins in combination with other antibiotics leads to better outcomes remains unknown. This review discusses the limitations of observational studies that suggest a benefit of combinations of colistin and carbapenems to treat infections caused by carbapenem-resistant Enterobacteriaceae (CRE), especially Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae, and summarizes the results of randomized controlled trials in which treatment with colistin in combination with meropenem or rifampin does not lead to better clinical outcomes than colisitn monotherapy in infections caused by carbapenem-resistant Acinetobacter baumannii (CRAB). Although the introduction of new antibiotics makes it possible to treat certain strains of CRE and carbapenem-resistant P. aeruginosa (CRPA) with polymyxin-sparing regimens, the use of polymyxins is, for now, still necessary in CRAB and in CRE and CRPA harboring metallo-beta-lactamases. Therefore, strategies must be developed to optimize polymyxin-based treatments, informed by in vitro hollow fiber models, careful clinical observations, and high-quality evidence from appropriately designed trials.


Author(s):  
E. S. Slazhneva ◽  
E. A. Tikhomirova ◽  
V. G. Atrushkevich

Relevance. The modern view of periodontitis as a dysbiotic disease that occurs as a result of changes in the microbial composition of the subgingival region is considered in a systematic review.Purpose. To study a new paradigm of development of generalized periodontitis.Materials and methods. Randomized controlled trials (RCTS) were selected for the study, including cluster RCTS, controlled (non-randomized) microbiological and clinical studies of the oral microbiome in adult patients with generalized periodontitis over the past 10 years.Results. The transition from a symbiotic microflora to a dysbiotic pathogenic community triggers the host's inflammatory response, which contributes to the development of periodontal diseases. Modern ideas about periodontal pathogenic bacteria dictate new requirements for the treatment of periodontal diseases. The second part of the review examines the microbial profiles of periodontal disease in various nosological forms, the mechanisms of the immune response and approaches to the treatment of periodontal disease from the perspective of biofilm infection.Conclusions. As follows from modern literature periodontitis is to a certain extent caused by the transition from a harmonious symbiotic bacterial community to a dysbiotic one. Recent scientific studies have shown that not single microorganism is not able to cause disease but the microbial community as a whole leads to the development of pathology.


2019 ◽  
Vol 24 (45) ◽  
pp. 5367-5374 ◽  
Author(s):  
Xiaoyun Li ◽  
Seyed M. Moosavi-Basri ◽  
Rahul Sheth ◽  
Xiaoying Wang ◽  
Yu S. Zhang

The role of endovascular interventions has progressed rapidly over the past several decades. While animal models have long-served as the mainstay for the advancement of this field, the use of in vitro models has become increasingly widely adopted with recent advances in engineering technologies. Here, we review the strategies, mainly including bioprinting and microfabrication, which allow for fabrication of biomimetic vascular models that will potentially serve to supplement the conventional animal models for convenient investigations of endovascular interventions. Besides normal blood vessels, those in diseased states, such as thrombosis, may also be modeled by integrating cues that simulate the microenvironment of vascular disorders. These novel engineering strategies for the development of biomimetic in vitro vascular structures will possibly enable unconventional means of studying complex endovascular intervention problems that are otherwise hard to address using existing models.


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