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The purpose of this paper is to present the methodology of a design process of new lumbar intervertebral disc implants with specific emphasis on the use of rapid prototyping technologies. The verification of functionality of artificial intervertebral discs is also given. The paper describes the attempt and preliminary research to evaluate the properties of the intervertebral disc implant prototypes manufactured with the use of different rapid prototyping technologies, i.e. FDM – fused deposition modelling, 3DP – 3D printing and SLM – selective laser melting.

Based on the computed tomography (CT) scan data, the anatomical parameters of lumbar spine bone tissue were achieved, which were the bases for the design-manufacture process carried out with the use of computer-aided designing/computer-aided engineering/computer-aided manufacturing systems. In the intervertebral disc implant design process, three RP technologies: FDM, 3DP and SLM were used for solving problems related to the reconstruction of geometry and functionality of the disc. Some preliminary tests such as measurement of roughness and structural analyses of material of prototypes made by different prototyping technologies were performed.

This paper allowed the authors to elaborate and patent two new intervertebral disc implants. Because the implant designs are parametrical ones with relation to lumbar bone tissue properties measured on CT scans, they can be also made for individual patients. We also compared some of the properties of intervertebral implants prototypes made with the use of FDM, 3DP and SLM technologies.

The paper presents the new intervertebral disc implants and their manufacturing by rapid prototyping. The methodology of designing intervertebral disc implant is shown. Some features of the methodology make it useful for preoperative planning of intervertebral disc surgery, as well.

Retrieval languages may have varied structural characteristics, and these are summarized. The languages serve varied purposes in information systems, and a number of these are identified. The relations between structure and function are discussed and suggestions made as to the most suitable structures needed for various purposes.

The purpose of this paper is to develop a process chain for design and manufacture of endplates of intervertebral disc implants, with specific emphasis on designing footprint profiles and matching endplate geometry.

Existing techniques for acquiring patient‐specific information from CT scan data was and a user‐friendly software solution was developed to facilitate pre‐surgical planning and semi‐automated design. The steps in the process chain were validated experimentally by manufacturing Ti6Al4 V endplates by means of Direct Metal Laser Sintering to match vertebrae of a cadaver and were tested for accuracy of the implant‐to‐bone fitment.

Intervertebral disc endplates were successfully designed and rapid manufactured using a biocompatible material. Accuracy within 0.37 mm was achieved. User‐friendly, semi‐automated design software offers an opportunity for surgeons to become more easily involved in the design process and speeds up the process to more accurately develop a custom‐made implant.

This research is limited to the design and manufacture of the bone‐implant contacting interface. Other design features, such as keels which are commonly used for implant fixation as well as the functionality of the implant joint mechanics were not considered as there may be several feasible design alternatives.

This research may change the way that current intervertebral disc implants are designed and manufactured.

Apart from other areas of application (cranial, maxillofacial, hip, knee, foot) and recent research on customized disc nucleus replacement, very little work has been done to develop patient‐specific implants for the spine. This research was conducted to contribute and provide much needed progress in this area of application.

Orthopaedic implants, such as intervertebral disc endoprostheses (IDEs) are difficult to manufacture by means of conventional methods because of their complex shape. However, technologies developed in recent years, such as selective laser melting, could simplify this process. Although this method is attractive in both manufacturing and rapid prototyping of IDEs, little is known about their tribological performance. The functional aim of the work is to conduct a tribological evaluation of the ASTM F75 alloy after selective laser melting process and to investigate the viability of the technology in IDE design. The research aim was an explanation of the wear mechanism of bearing surfaces with respect to the reference material.

In this paper, the tribological test results of a lumbar IDE prototype fabricated by selective laser melting and forging is presented and compared. The endoprostheses were fabricated from commercially available ASTM F75 powder using a selective laser melting device. As a reference material, a forged ASTM F1537 LC alloy was used. Comparative wear and friction tests were carried out with the use of a unique spine simulator.

The obtained results confirm the viability of the selective laser technology in endoprosthesis design. Unfortunately, poorer tribological wear resistance of endoprostheses produced by means of selective laser melting (SLM) technology compared with that of the reference material calls into question the possibility of using these technologies in the manufacturing process of endoprosthesis' components exposed to tribological wear.

This paper presents the friction and wear behaviour of the lumbar IDE prototype. The tests were carried out in motion and loading conditions close to those we observe in the lumbar spine.

This bibliography is offered as a practical guide to published papers, conference proceedings papers and theses/dissertations on the finite element (FE) and boundary element (BE) applications in different fields of biomechanics between 1976 and 1991. The aim of this paper is to help the users of FE and BE techniques to get better value from a large collection of papers on the subjects. Categories in biomechanics included in this survey are: orthopaedic mechanics, dental mechanics, cardiovascular mechanics, soft tissue mechanics, biological flow, impact injury, and other fields of applications. More than 900 references are listed.

The purpose of this paper is to discover best practices for selling stem cell based biologics and ensuring proper sales force alignment in the biomedical device industry.

This research is based on an immersion into the industry as well as several formal, semi-structured interviews and dozens of informal interviews of surgeons, medical staff and medical device salespersons and managers. Data were also collected and analyzed from wipricepoint.org. The factors analyzed were the number of discharges, average charge per procedure, median age, male/female patient ratio and total hospital charges per year.

Secondary data can augment primary data collection to determine the most lucrative markets for salespersons to target their efforts. In addition, the data when combined with sales force specific data can help optimize sales force alignment. Insights into the industry are also given such as how to overcome objections to the use of stem cell based biologics for spinal surgeries.

Much of the findings are specific to only one industry (medical device sales). However, we do present a generalized process for analyzing a key source of secondary data that could be beneficial to any hospital-serving industry.

Within the medical equipment industries, approximately 58 per cent of sales territories were either too large or too small (Zoltners and Lorimer, 2000). This paper shows how secondary data sources can be obtained and analyzed to better focus sales force effort.

This paper aims to study the wear properties of electron beam melted Ti6Al4V (EBM-Ti6Al4V) in simulated body fluids for orthopedic implant biomedical applications compared with wrought Ti6Al4V (Wr-Ti6Al4V).

Wear properties of EBM-Ti6Al4V compared with Wr-Ti6Al4V against ZrO₂ and Al₂O₃ have been investigated under dry friction and the 25 Wt.% newborn calf serum (NCS) lubricated condition using a ball-on-disc apparatus reciprocating motion. The microstructure, composition and hardness of the samples were characterized using scanning electron microscopy (SEM), x-ray diffraction and a hardness tester, respectively. The contact angles with 25 Wt.% NCS were measured by a contact angle apparatus. The wear parameters, wear 2D and 3D morphology were obtained using a 3D white light interferometer and SEM.

EBM-Ti6Al4V yields a higher contact angle than the Wr-Ti6Al4V with the 25 Wt.% NCS. EBM-Ti6Al4V couplings exhibit lower coefficients of friction compared with the Wr-Ti6Al4V couplings under both conditions. There is only a slight difference in the wear resistance between the Wr-Ti6Al4V and EBM-Ti6Al4V alloys. Both Wr-Ti6Al4V and EBM-Ti6Al4V suffer from similar friction and wear mechanisms, i.e. adhesive and abrasive wear in dry friction, while abrasive wear under the NCS condition. The wear depth and wear volume of the ZrO₂ couplings are lower than those of the Al₂O₃ couplings under both conditions.

This paper helps to establish baseline bio-tribological data of additively manufactured Ti6Al4V by electron beam melting in simulated body fluids for orthopedic applications, which will promote the application of additive manufacturing in producing the orthopedic implant.

Acute and chronic pain affects more Americans than heart disease, diabetes, and cancer combined. Conservative estimates suggest the total economic cost of pain in the United States is $600 billion, and more than half of this cost is due to lost productivity, such as absenteeism, presenteeism, and turnover. In addition, an escalating opioid epidemic in the United States and abroad spurred by a lack of safe and effective pain management has magnified challenges to address pain in the workforce, particularly the military. Thus, it is imperative to investigate the organizational antecedents and consequences of pain and prescription opioid misuse (POM). This chapter provides a brief introduction to pain processing and the biopsychosocial model of pain, emphasizing the relationship between stress, emotional well-being, and pain in the military workforce. We review personal and organizational risk and protective factors for pain, such as post-traumatic stress disorder, optimism, perceived organizational support, and job strain. Further, we discuss the potential adverse impact of pain on organizational outcomes, the rise of POM in military personnel, and risk factors for POM in civilian and military populations. Lastly, we propose potential organizational interventions to mitigate pain and provide the future directions for work, stress, and pain research.

This paper describes an investigation into the ability of man to withstand the environmental stresses existing at the high altitudes associated with supersonic flight. The medical histories of a group of pilots who had been exposed to altitudes in excess of 50,000 ft. were compared with those of a control group whose flying had been confined to normal altitudes. The total exposure time of the test group was estimated to be in excess of 35,000 hours. Dr Charles I. Barron is the Medical Director of the Lockheed‐California Company. He is a graduate of the University of Illinois College of Medicine, and he served as a flight surgeon in the Army Air Corps during World War II. He has been engaged in extensive research work and has published numerous papers on the effects of aircraft noise, microwave radiation, escape systems, decompression, and on various aspects of human engineering. He is a past president of the Aerospace Medical Association and has served on the National Research Council Committee. At present, he is the Chairman of the Research Advisory Committee on Biotechnology and Human Research for N.A.S.A. and Chairman of the Medical Advisory Council to the Federal Air Surgeon. He is a lecturer in aviation physiology in the Aerospace Safety Division at U.S.C., and an Associate Professor of Aerospace Pathology at U.C.L.A.

May 13, 1969 Building — Safety regulations — Scaffold — Work done by scaffolders on shore arm to secure guard rails pending grouting by main contractors — Whether “building operation” or “work of engineering construction” — Scaffolders' employee injured by hole in road surface of shore arm — Whether negligence — Whether safe means of access and place of work — Whether “Scaffold” — Construction (General Provisions) Regulations, 1961 (S.I. 1961, No. 1580), regs. 2(1), 3(1), 4(2), 7(1).