scholarly journals An Intelligent Bone Spinal Disc Implant for Asian Population

2009 ◽  
Vol 3 (2) ◽  
Author(s):  
C. Chui ◽  
M. N. Jonaidi ◽  
S. Kuang
Keyword(s):  
Computer Simulation ◽  
Vertebral Body ◽  
Pressure Sensors ◽  
Asian Population ◽  
Control Mechanisms ◽  
Disc Disease ◽  
Fibre Optics ◽  
Motion Preservation ◽  
Spinal Disc ◽  
Prototype Device

There is a high level of patient appeal and physician acceptance of motion preservation as the future treatment of symptomatic and painful degenerative disc disease. However, spinal artificial disc replacement is still in its infancy. We have been designing, developing and evaluating motor articulated implants for use in bone-spinal disc surgery for Asian population. Apart from the generally smaller built of Asian compared to the American and European, the motor articulated implant should make provisions for the difference in eastern and western lifestyles. In the eastern world, we generally sit on a lower platform. Frequent activities like squatting result in a different stress-strain profile on the lower spine of an Asian compared to that of the Westerner. Preserving the motion of flexion bending in human lumbar spine is important. The motion preservation characteristics have to be maintained without compromising device durability, bone-device interfaces and corrective intervention. A systematic approach was adapted in designing the implant. Physical size of the implant should replicate the actual Intravertebral Disc (IVD). Implant should be able to fit into vertebral body. This is aid by shaping the spine vertebral body to accommodate the implant. A motor articulated implant must have suitable spaces for the implementation of sensors to detect forces and motors to control the motion of the prototype. The device must be able to receive real-time sensory inputs which can then modulate the implant orientation in bending accordingly. A prototype of the implant device has been fabricated to study its motion preservation capabilities. The prototype comprises of a parallel manipulator mechanism where the top plate is linked to the base plate by independent kinematic chains. The mechanical structure is made of Aluminium 6061. The mechanical parts were also put through the chemical process of anodizing for a good finishing surface. In the prototype device, we used three DC micromotors (Faulhaber) for actuation. Due to the small dimension, fibre optics pressure sensors were used. Three customized sensors were developed, calibrated and deployed on the upper plate. A PIC32 microprocessor was used to compute the compliance motion of the prototype when subjected to forces during flexion bending motion. The computer simulation of the kinematics of the parallel mechanism demonstrated the implant's flexion bending capabilities. We are conducting biomechanical experiments with this prototype implant deployed between L3–L5 of an artificial spinal column. The prototype device should achieve motion preservation capabilities comparable to the existing implants. More computer simulation will also be conducted to improve the mechanical design and control mechanisms of the proposed disc implant.

scholarly journals Two-level cervical arthroplasty using a “no-distraction” technique

2017 ◽  
Vol 42 (videosuppl1) ◽  
pp. V1
Author(s):  
Deshpande Rajakumar ◽  
Ankit Sharma ◽  
Akshay Hari ◽  
Subhas Konar ◽  
Murali Krishna
Keyword(s):  
Surgical Technique ◽  
Neck Pain ◽  
Vertebral Body ◽  
Degenerative Disease ◽  
Anterior Cervical Fusion ◽  
Cervical Fusion ◽  
Cervical Arthroplasty ◽  
Motion Preservation ◽  
Link Type

Cervical arthroplasty is being recognized as an emerging alternative to anterior cervical fusion with comparable or superior outcomes. The authors describe the surgical nuances of 2-level cervical arthroplasty in a case of 2-level degenerative disease. In this surgical technique, conventional vertebral body distraction has been avoided to prevent facet distraction, which can be a cause of persistent postoperative neck pain. Good motion preservation was observed at the 1-year follow-up examination.The video can be found here: https://youtu.be/YTpRVRXuZZk.

A Theoretical Model of Infant Incubator Dynamics

1994 ◽  
Vol 116 (3) ◽  
pp. 263-269 ◽  
Author(s):  
Barry N. Simon ◽  
Narender P. Reddy ◽  
Anand Kantak
Keyword(s):  
Mathematical Model ◽  
Heart Rate ◽  
Computer Simulation ◽  
Heat Capacity ◽  
Thermal Properties ◽  
Theoretical Model ◽  
Parametric Analysis ◽  
Control Mechanisms ◽  
Air Flow Rate ◽  
Infant Incubator

A spatially lumped mathematical model was developed and used for a computer simulation of the neonate-incubator system for parametric analysis of the factors that influence neonatal thermo-regulation. The simulation examined the effects of the following parameters: (1) size of the infant; (2) respiratory rate; (3) metabolic rate; (4) heart rate; (5) thermal properties of the mattress; (6) specific heat capacity of the incubator wall; (7) air flow rate; (8) heater control mechanisms.

Active Acoustic Control of Sound Transmission through Double Walls: Simulation Results

2000 ◽  
Vol 7 (2) ◽  
pp. 127-135
Author(s):  
C. Bao ◽  
J. Pan
Keyword(s):  
Computer Simulation ◽  
Sound Transmission ◽  
Theoretical Framework ◽  
Control Mechanisms ◽  
Control Performance ◽  
Acoustic Control ◽  
Modal Density ◽  
Simulation Based ◽  
Analytical Work ◽  
Active Acoustic Control

In this paper, the active control of sound transmission through double-panel partitions by inserting acoustic sources in the air gap between the double panels is studied through a computer simulation. The work is an extension of the previous analytical work in which a theoretical framework was developed to reveal the control mechanisms involved in active acoustic control. In this work, a computer simulation based on the theoretical framework is used to assess the control performance under different conditions. It is shown that the property of the radiating panel plays an important role in active acoustic control. The control performance can be improved by increasing the panel damping or decreasing the panel modal density. The reasons for this are discussed.

scholarly journals Multi-purpose information-measuring system for vertical profiling of the ocean environment

2021 ◽  
pp. 54-60
Author(s):  
L.A. Krasnodubets ◽  
◽  
Keyword(s):  
Computer Simulation ◽  
Speed Of Sound ◽  
Sea Water ◽  
Pressure Sensors ◽  
Real Data ◽  
Measuring System ◽  
Information Measuring ◽  
Information Measuring System ◽  
Vertical Profiling ◽  
Ocean Environment

On the basis of a mathematical description of the processes of measuring the vertical profile of the density of the oceanic environment using a diving offshore autonomous probe – a profiler equipped with an onboard navigation system, a structure and a computer model of a multipurpose information-measuring system is proposed, which is intended for use in operational oceanology. The proposed system forms arrays of measurements of vertical profiles in situ of the density of seawater and its increment, as well as the speed of sound as functions of hydrostatic pressure, obtained during one sounding. At the same time, arrays of complete and thermohaline vertical stability of water layers, as well as the corresponding vertical distributions of the Väisälä-Brunt frequency of thermohaline oscillations in the stratified ocean environment, are formed almost in parallel. In the course of the simulation, an original model of the immersion of an autonomous marine probe in stratified sea water was used, as well as a dynamic model for measuring the trajectory parameters of its movement, taking into account the inertial properties of the acceleration and pressure sensors used. As an object of measurements, we used a simulation model of the ocean environment with vertical density stratification and the corresponding speed of sound in seawater, developed on the basis of real data of profile measurements obtained from specific hydrological stations. The verification of the models of the dynamic measurement processes was carried out by the method of computer simulation in the MATLAB & Simulink environment based on the comparison between the simulation results and available results from the hydrological stations. The illustrations of the results of computer simulation are presented.

Multi-Axis Testing of an Elastomeric Prosthetic Lumbar Disc Compared to a Cadaveric Human Disc

2007 ◽  
Author(s):  
Glen Njus ◽  
James Price ◽  
Anand Parikh ◽  
Snehal Chokhandre ◽  
John Konicek ◽  
...  
Keyword(s):  
Mechanical Testing ◽  
Degenerative Disc Disease ◽  
Mechanical Performance ◽  
Lumbar Disc ◽  
Disc Replacement ◽  
Disc Disease ◽  
Lumbar Degenerative Disc Disease ◽  
Safety And Efficacy ◽  
Motion Preservation

As motion preservation implants begin to replace fusion devices for lumbar degenerative disc disease, preclinical mechanical testing of these devices is critical to predicting their in vivo safety and efficacy. ISO and ASTM standards committees have tried for years to develop a universal test standard for all lumbar disc implants. The eDisc, an elastomeric/titanium disc replacement, is substantially different in its mechanical performance than the Synthes ProDisc or J&J Charite disc. These discs rely on ball and socket motion about a fixed or moving center or rotation to provide motion restoration in 3 to 5 axes. In contrast, the eDisc has viscoelastic motion in 3 translation and 3 rotational directions, just as in the natural human disc.

scholarly journals Gene locus polymorphisms and expression levels of interleukin-1 in lumbar disc disease: a meta-analysis and immunohistochemical study

2020 ◽  
Author(s):  
Hua Jiang ◽  
Qianyi Xiao ◽  
Ruijun Zhang ◽  
Jiaqi Wang ◽  
Dihua Meng ◽  
...  
Keyword(s):  
Gene Locus ◽  
Lumbar Disc ◽  
Meta Analysis ◽  
Variable Number Tandem Repeat ◽  
Asian Population ◽  
Disc Disease ◽  
Lumbar Disc Disease ◽  
Expression Levels ◽  
Qrt Pcr ◽  
Increased Risk

Abstract Background: To investigate the association between interleukin (IL)-1α (rs1800587), IL-1β (rs1143634) and IL-1 receptor antagonist (RN) variable number tandem repeat (VNTR) polymorphisms, expression levels and lumbar disc disease (LDD).Methods: All relevant articles were searched from 4 databases including PubMed, Embase, Web of Science and China National Knowledge Infrastructure (CNKI). Odds ratios (OR) with 95 % confidence intervals (CI) were calculated to evaluate the association between IL-1 gene locus polymorphisms (rs1800587 in IL-1α, rs1143634 in IL-1β, VNTR in IL-1RN) and LDD susceptibility. Statistical analysis was conducted by Review Manager (Revman) 5.31 software. Furthermore, qRT-PCR and immunohistochemistry (IHC) were performed to evaluate IL-1α, IL-1β and IL-1RN expressions in the normal and degenerated disc.Results: A total of 15 case-control studies (1455 cases and 2362 controls) were included in our meta-analysis. The pooled results suggested that IL-1α rs1800587 polymorphism was associated with an increased risk of LDD in overall population (T vs. C, OR=1.21, 95%CI=1.04-1.40, P=0.01). The subgroup analysis found a significant association between IL-1β rs1143634 polymorphism and LDD in Asian population (T vs. C, OR=0.61, 95%CI=0.39-0.96, P=0.03). Results of qRT-PCR and IHC demonstrated that expressions of IL-1α and IL-1-β were significantly increased in the degenerated disc. (all P<0.05 )Conclusion: IL-1α rs1800587 and IL-1β rs1143634 polymorphisms were significantly associated with LDD in overall population and in Asian population, respectively.

Effects of collagenase upon the intervertebral disc in monkeys

1976 ◽  
Vol 44 (1) ◽  
pp. 32-44 ◽  
Author(s):  
W. Eugene Stern ◽  
Walter F. Coulson
Keyword(s):  
Bone Formation ◽  
Vertebral Body ◽  
Fibrous Tissue ◽  
Intervertebral Discs ◽  
Disc Disease ◽  
Content Type ◽  
Tissue Changes ◽  
Vertebral Bodies ◽  
Radiographic Changes ◽  
Limited Scope

✓ The authors studied five rhesus monkeys for the effects of annulotomy, with or without the addition of a bacterially-derived collagenase into the nuclear-evacuated centrum of lumbar intervertebral discs. The animals were sacrificed from 3 weeks to 21 months after the single or staged double procedures. The earliest radiographic changes were loss of height of the interspace at 7 days, erosion of the vertebral body margins at 3 weeks, malalignment at 6 weeks, osteophytic formation at 3½ months, sclerosis of vertebral body surfaces at 9½ months, and fusion of adjacent vertebral bodies at 13½ months. Pathological changes included early loss of disc convexity, focal new bone formation, osteophytic new growth, through-and-through bone formation, irregular cystification, and disc replacement by hyaline fibrous tissue. Changes were reminiscent of those seen in humans with naturally acquired disc disease or aging of the disc. Injuries were produced in a tissue that probably has a limited scope of variation in reaction to insult.

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