A Multi-Axis Programmable Spine Robot: Application Towards Kinematic Assessments of the Lumbar MSU

2008 ◽  
Author(s):  
Brian P. Kelly ◽  
Nephi A. Zufelt ◽  
Elizabeth J. Sander ◽  
Denis J. DiAngelo
Keyword(s):  
Biomechanical Testing ◽  
Dynamic State ◽  
Limited Data ◽  
Instantaneous Axis Of Rotation ◽  
New Methods ◽  
Methods Of Evaluation ◽  
Mechanical Devices ◽  
Spine Robot ◽  
Testing Protocols

Current in vitro testing methodologies remain limited in the ability to explore spinal dynamics. The gold standard of flexibility testing has traditionally focused on evaluating MSU rotational ranges of motion only. While such data may be applied towards evaluation of the Instantaneous Axis of Rotation (IAR), many systems lack the needed sensitivity. The result is that there is currently no consensus on the location of the IAR. Further, very limited data or insight can be gathered as to the precise kinematic or dynamic state of the MSU, or the influence of surgically implanted motion restoration devices. For example, total disc arthroplasty devices are typically rigid mechanical devices that impose an IAR or IAR range. How might this imposed IAR affect MSU mechanics? How might variations in surgical placement of an implant be scientifically quantified? More recently an emerging group of compliant motion restoration devices are being developed that require new methods of evaluation. How well does a compliant device restore the native mechanics of the disc or MSU? To address and understand these increasingly important issues, novel, more advanced biomechanical testing protocols need to be developed.

Use of Spine Robot Employing Real Time Force Control to Simulate a Pure Moment Protocol for the Subaxial Cervical Spine: An In Vitro Biomechancial Study

2011 ◽  
Author(s):  
Daniel M. Wido ◽  
Denis J. DiAngelo ◽  
Brian P. Kelly
Keyword(s):  
Cervical Spine ◽  
Real Time ◽  
Force Control ◽  
Biomechanical Testing ◽  
Subaxial Cervical Spine ◽  
Experimental Artifact ◽  
Pure Moment ◽  
Robotic Testing ◽  
Spine Robot

A standard biomechanical testing protocol for evaluation of the sub-axial cervical spine is the application of pure bending moments to the free end of the spine (with opposing end fixed) and measurement of its motion response. The pure moment protocol is often used to compare spinal fusion instrumentation and has also been used to evaluate non-fusion instrumentation (e.g. disc arthroplasty devices) [1,2]. A variety of different testing systems have been employed to implement pure moment application. In cases where the loading is applied quasi-statically using a series of weights and pulleys the spine may relax between intermittent loading phases and/or unintended loading may be applied causing experimental artifact. Our objective was to use an existing programmable robotic testing platform (Spine Robot) to develop a novel real time force control strategy to simulate pure moment loading under precisely controlled continuous movement conditions. This would serve to advance robotic testing capabilities with an end goal to simulate different protocols in the same platform, and to potentially minimize fixturing and quasi-static artifacts.

Does Placement of the Axis of Rotation of the Cervical Spine Affect Motion Segment Mechanics During Flexion and Extension?

2009 ◽  
Author(s):  
Brian P. Kelly ◽  
Henry Bonin ◽  
Kyle Fraysur ◽  
Karen Sedacki ◽  
Denis J. DiAngelo
Keyword(s):  
Gold Standard ◽  
Dynamic State ◽  
Limited Data ◽  
Axis Of Rotation ◽  
Motion Segment ◽  
Rotational Components ◽  
Spinal Mechanics ◽  
Implanted Device ◽  
Flexion And Extension

Current in vitro testing methodologies remain limited in the ability to explore spinal mechanics. The gold standard of flexibility testing has traditionally focused only on evaluating rotational components of motion within a motion segment unit (MSU). While such data may be applied towards evaluation of the Center of Rotation (CoR) of a joint, many systems lack the needed sensitivity. The result is that there is currently no consensus on the location of the CoR of the spine. Further, very limited data or insight can be gathered as to the precise kinematic or dynamic state of the MSU, the influence of surgically implanted motion restoration devices, or the influence of subtle changes to an implanted device.

scholarly journals The Current Testing Protocols for Biomechanical Evaluation of Lumbar Spinal Implants in Laboratory Setting: A Review of the Literature

2015 ◽  
Vol 2015 ◽  
pp. 1-15 ◽  
Author(s):  
Sabrina A. Gonzalez-Blohm ◽  
James J. Doulgeris ◽  
William E. Lee ◽  
Thomas M. Shea ◽  
Kamran Aghayev ◽  
...  
Keyword(s):  
Biomechanical Testing ◽  
Laboratory Setting ◽  
Review Of The Literature ◽  
Standard Testing ◽  
Spinal Implants ◽  
Current Trends ◽  
Biomechanical Evaluation ◽  
Lumbar Spinal ◽  
Testing Protocols

In vitrobiomechanical investigations have become a routinely employed technique to explore new lumbar instrumentation. One of the most important advantages of such investigations is the low risk present when compared to clinical trials. However, the best use of any experimental data can be made when standard testing protocols are adopted by investigators, thus allowing comparisons among studies. Experimental variables, such as the length of the specimen, operative level, type of loading (e.g., dynamic versus quasistatic), magnitude, and rate of load applied, are among the most common variables controlled during spinal biomechanical testing. Although important efforts have been made to standardize these protocols, high variability can be found in the current literature. The aim of this investigation was to conduct a systematic review of the literature to identify the current trends in the protocols reported for the evaluation of new lumbar spinal implants under laboratory setting.

scholarly journals Lumbar Interbody Fusion Conducted on a Porcine Model with a Bioresorbable Ceramic/Biopolymer Hybrid Implant Enriched with Hyperstable Fibroblast Growth Factor 2

Biomedicines ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 733
Author(s):  
Milan Krticka ◽  
Ladislav Planka ◽  
Lucy Vojtova ◽  
Vladimir Nekuda ◽  
Premysl Stastny ◽  
...  
Keyword(s):  
Growth Factor ◽  
Lumbar Fusion ◽  
Biomechanical Testing ◽  
Fibroblast Growth Factor 2 ◽  
Oxidized Cellulose ◽  
Fibroblast Growth ◽  
Micro Ct ◽  
Bone Autograft ◽  
Autograft Group

Many growth factors have been studied as additives accelerating lumbar fusion rates in different animal models. However, their low hydrolytic and thermal stability both in vitro and in vivo limits their workability and use. In the proposed work, a stabilized vasculogenic and prohealing fibroblast growth factor-2 (FGF2-STAB®) exhibiting a functional half-life in vitro at 37 °C more than 20 days was applied for lumbar fusion in combination with a bioresorbable scaffold on porcine models. An experimental animal study was designed to investigate the intervertebral fusion efficiency and safety of a bioresorbable ceramic/biopolymer hybrid implant enriched with FGF2-STAB® in comparison with a tricortical bone autograft used as a gold standard. Twenty-four experimental pigs underwent L2/3 discectomy with implantation of either the tricortical iliac crest bone autograft or the bioresorbable hybrid implant (BHI) followed by lateral intervertebral fixation. The quality of spinal fusion was assessed by micro-computed tomography (micro-CT), biomechanical testing, and histological examination at both 8 and 16 weeks after the surgery. While 8 weeks after implantation, micro-CT analysis demonstrated similar fusion quality in both groups, in contrast, spines with BHI involving inorganic hydroxyapatite and tricalcium phosphate along with organic collagen, oxidized cellulose, and FGF2- STAB® showed a significant increase in a fusion quality in comparison to the autograft group 16 weeks post-surgery (p = 0.023). Biomechanical testing revealed significantly higher stiffness of spines treated with the bioresorbable hybrid implant group compared to the autograft group (p < 0.05). Whilst histomorphological evaluation showed significant progression of new bone formation in the BHI group besides non-union and fibrocartilage tissue formed in the autograft group. Significant osteoinductive effects of BHI based on bioceramics, collagen, oxidized cellulose, and FGF2-STAB® could improve outcomes in spinal fusion surgery and bone tissue regeneration.

scholarly journals Comparative in vitro study and biomechanical testing of two different magnesium alloys

2013 ◽  
Vol 28 (8) ◽  
pp. 1264-1273 ◽  
Author(s):  
Andreas Weizbauer ◽  
Christian Modrejewski ◽  
Sabine Behrens ◽  
Helmut Klein ◽  
Patrick Helmecke ◽  
...  
Keyword(s):  
Magnesium Alloys ◽  
Biomechanical Testing ◽  
In Vitro Study ◽  
Vitro Study

scholarly journals New Methods of Entropy-Robust Estimation for Randomized Models under Limited Data

Entropy ◽  
2014 ◽  
Vol 16 (2) ◽  
pp. 675-698 ◽  
Author(s):  
Yuri Popkov ◽  
Alexey Popkov
Keyword(s):  
Robust Estimation ◽  
Limited Data ◽  
New Methods

Cervical Plate Stiffness Affects the Distribution of Loads and the Location of the Instantaneous Axis of Rotation of the Spine In Vitro

2016 ◽  
Vol 16 (10) ◽  
pp. S260-S261 ◽  
Author(s):  
Josh Peterson ◽  
Carolyn Chlebek ◽  
Ashley Clough ◽  
Alexandra Wells ◽  
Eric H. Ledet
Keyword(s):  
Instantaneous Axis Of Rotation ◽  
Axis Of Rotation ◽  
Cervical Plate ◽  
Instantaneous Axis

An aniline-substituted bile salt analog protects both mice and hamsters from multiple Clostridioides difficile strains

2021 ◽  
Author(s):  
Jacqueline R. Phan ◽  
Dung M. Do ◽  
Minh Chau Truong ◽  
Connie Ngo ◽  
Julian H. Phan ◽  
...  
Keyword(s):  
Bile Salt ◽  
Spore Germination ◽  
Dependent Manner ◽  
Germination Inhibitors ◽  
New Methods ◽  
Clostridioides Difficile ◽  
Antibiotic Associated Diarrhea ◽  
Careful Screening ◽  
Strain Dependent

Clostridioides difficile infection (CDI) is the major identifiable cause of antibiotic-associated diarrhea. The emergence of hypervirulent C. difficile strains has led to increases in both hospital- and community-acquired CDI. Furthermore, CDI relapse from hypervirulent strains can reach up to 25%. Thus, standard treatments are rendered less effective, making new methods of prevention and treatment more critical. Previously, the bile salt analog CamSA was shown to inhibit spore germination in vitro and protect mice and hamsters from C. difficile strain 630. Here, we show that CamSA was less active at preventing spore germination of other C. difficile ribotypes, including the hypervirulent strain R20291. Strain-specific in vitro germination activity of CamSA correlated with its ability to prevent CDI in mice. Additional bile salt analogs were screened for in vitro germination inhibition activity against strain R20291, and the most active compounds were tested against other strains. An aniline-substituted bile salt analog, (CaPA), was found to be a better anti-germinant than CamSA against eight different C. difficile strains. In addition, CaPA was capable of reducing, delaying, or preventing murine CDI signs in all strains tested. CaPA-treated mice showed no obvious toxicity and showed minor effects on their gut microbiome. CaPA’s efficacy was further confirmed by its ability to prevent CDI in hamsters infected with strain 630. These data suggest that C. difficile spores respond to germination inhibitors in a strain-dependent manner. However, careful screening can identify anti-germinants with broad CDI prophylaxis activity.

In vitro effectiveness of biapenem against IMP-producing Enterobacteriaceae

2021 ◽  
Vol 70 (10) ◽  
Author(s):  
Kazuyoshi Gotoh ◽  
Makoto Miyoshi ◽  
I Putu Bayu Mayura ◽  
Koji Iio ◽  
Osamu Matsushita ◽  
...  
Keyword(s):  
Therapeutic Option ◽  
Small Data ◽  
Limited Data ◽  
Data Set ◽  
Content Type ◽  
Link Type ◽  
Almost All ◽  
New Treatments ◽  
Time Kill

The options available for treating infections with carbapenemase-producing Enterobacteriaceae (CPE) are limited; with the increasing threat of these infections, new treatments are urgently needed. Biapenem (BIPM) is a carbapenem, and limited data confirming its in vitro killing effect against CPE are available. In this study, we examined the minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) of BIPM for 14 IMP-1-producing Enterobacteriaceae strains isolated from the Okayama region in Japan. The MICs against almost all the isolates were lower than 0.5 µg ml−1, indicating susceptibility to BIPM, while approximately half of the isolates were confirmed to be bacteriostatic to BIPM. However, initial killing to a 99.9 % reduction was observed in seven out of eight strains in a time–kill assay. Despite the small data set, we concluded that the in vitro efficacy of BIPM suggests that the drug could be a new therapeutic option against infection with IMP-producing CPE.

Sign in / Sign up

Export Citation Format

Share Document