Bio-Medical Materials and Engineering - Volume 3, issue 1

Authors: Vander Sloten, J. | Labey, L. | Van Audekercke, R. | Van Der Perre, G.

Article Type: Research Article

Abstract: Based upon previous research on the relation between hip prosthesis designs and strain distributions in a proximal femur model, a prototype of a “physiological” hip prosthesis was designed and manufactured. Strain gauge measurements on a dry femur before and after implantation of this prosthesis were made in different loading conditions simulating one-legged stance with and without torsional loading and two-legged stance. The strains in the outer cortex were within 10% of the physiological values along the whole medial side in all measurement conditions.

Keywords: biomechanics, physiological hip implant, strain gauging

DOI: 10.3233/BME-1993-3101

Citation: Bio-Medical Materials and Engineering, vol. 3, no. 1, pp. 1-13, 1993

Authors: Myers, Thomas J. | Yoganandan, Narayan | Sances Jr., Anthony | Pintar, Frank A. | Reinartz, John | Battocletti, Joseph H.

Article Type: Research Article

Abstract: The purpose of this study was to examine the force-deformation characteristics of football helmets subjected to compressive loading on the crown surface. Tests were conducted at quasi-static and dynamic rates of loading. Energies were computed from the force-deformation data. The padding systems represented by the helmets differed in their ability to absorb energy under varying loading rates. Helmets using pneumatic or combination pneumatic-foam padding systems were the most successful while suspension helmets were able to absorb the least amount of energy. The evaluation of energy absorption characteristics is an alternative method of describing the effectiveness of football helmets in preventing …head injury. Show more

Keywords: football helmets, energy absorption, impact testing, compression testing, head injury

DOI: 10.3233/BME-1993-3102

Citation: Bio-Medical Materials and Engineering, vol. 3, no. 1, pp. 15-24, 1993

Authors: Aoki, Hideki | Okayama, Shin | Kondo, Kouichi | Akao, Masaru

Article Type: Research Article

Abstract: The effect of exercise on strength and chemical composition of rat femur bone was examined. Ten 5-week-old rats were forced to exercise on a treadmill with a running speed of 20 mlmin at set time intervals for a 4-week period. Another 10 rats were kept idle as controls. After exercising, bending tests of the rat femur bones were carried out, and the content ratios of Sr to Ca, Sr/Ca, were measured by energy-dispersive fluorescent X-ray analysis and EPMA line analysis. The strength of the exercise group was greater than that of the control group. The ratio, Sr/Ca, of the exercise …group showed a tendency to increase compared to that of the control group. It is clear that the chemical composition of bone varies with the degree of exercise, and that the bone becomes strengthened at the same time. Show more

Keywords: bone apatite, exercise, bone strength, strontium

DOI: 10.3233/BME-1993-3103

Citation: Bio-Medical Materials and Engineering, vol. 3, no. 1, pp. 25-31, 1993

Authors: Guglielmino, E. | La Rosa, G. | Russo, T. C.

Article Type: Research Article

Abstract: The aim of the present research is to analyse the mechanical behaviour of the Cotrel-Dubousset spine internal fixator using numerical and experimental techniques. Simple experimental and numerical models of a spine section (four vertebrae of the thoraco-Iumbar region) were developed in order to evaluate the response of the system, particularly the stress-strain state in the rods, by means of strain-gauge measurements. The system was subjected to combined compressive and bending static loading and the deformations of the system were measured on models simulating physiological and pathological conditions, with and without the fixator.

Keywords: spine, internal fixator, numerical analysis

DOI: 10.3233/BME-1993-3104

Citation: Bio-Medical Materials and Engineering, vol. 3, no. 1, pp. 33-42, 1993

Authors: Torrisi, L.

Article Type: Research Article

Abstract: Pulsed laser deposition of hydroxyapatite is applied to cover titanium medical prothesis. Laser irradiation of ceramics by power-pulsed ruby laser produces high velocity micron-size particles emission with a narrow ejection plume directed normally to the target surface. Photoemitted particles are deposited on a metal surface at 400°C to obtain a granular film, stoichiometric, polycrystalline, and very adherent to the substrate. Deposited films are highly biocompatible and may be used to induce osteointegration processes of the implanted prothesis with the bone tissues. The comparison between laser and plasma spray depositions of biocerarnics is discussed.

Keywords: hydroxyapatite, photodeposition, plasma spray, medical prothesis

DOI: 10.3233/BME-1993-3105

Citation: Bio-Medical Materials and Engineering, vol. 3, no. 1, pp. 43-49, 1993

Authors: Dion, I. | Roques, X. | Baquey, H. | Baudet, E. | Basse Cathalinat, B. | More, N.

Article Type: Research Article

Abstract: The new prosthetic heart valve that has been designed by FII Company and Pr. Baudet involves a new “composite” material: titanium alloy T16A14V coated with Diamond-like Carbon. The purpose of this study was to evaluate the in vitro hemocompatibility of this new material in terms of protein adsorption and platelet retention. The static protein adsorption test gave interesting results, particularly for the albumin assay (237%) compared to the results obtained with a silicone elastomer chosen as a reference; the fibrinogen quantity, adsorbed on the surface of the material was slightly higher than that adsorbed on the silicone surface. Platelets adhere …quite twice as much as they do on the reference surface. Such investigations showed good hemocompatibility results and should initiate further studies. Show more

Keywords: diamond-like carbon, hemocompatibility, heart valves, biomaterials

DOI: 10.3233/BME-1993-3106

Citation: Bio-Medical Materials and Engineering, vol. 3, no. 1, pp. 51-55, 1993