Author/Editor		Košak, Robert
Title		Vpliv rentgenskih in biomehanskih parametrov na velikost in smer obrabe polietilenskih čašic totalnih kolčnih endoprotez
Type		monografija
Place		Ljubljana
Publisher		Medicinska fakulteta
Publication year		2006
Volume		str. 64
Language		slo
Abstract		Introduction: The aseptic loosening of an artificial hip joint is nowadays the main reason for the replacement of one or both components of the artificial hip. The important contributory factors for the occurrence of the aseptic loosening of the artificial hip joint are polyethylene cups. The number of polyethylene wear particles, which are produced during the use of endoprosthesis, is considerably bigger than the number of wear particles from other components of endoprosthesis. The degree of inflammation depends mainly on the number of wear particles. Since the number of polyethylene wear particles is far the greatest, polyethylene cups trigger the main part of the inflammation process. This is why they are the main reason for the loosening of the hip endoprosthesis. The effect of the radiographic parameters (the shape and size of the pelvis and of the proximal part of femur) and biomechanical parameters (the resultant hip joint force and the contact hip joint stress) on the wear of polyethylene cups has not been studied so far so it is still unknown. Only the analyses on the hips with no artificial material inserted have been made up to the present time. On the basis of these analyses they determined that the wear of the hip joint depended on the contact hip joint stress. Degenerative focal areas usually occur on those areas of the hip joint surface where stress tensions stay high for a longer period. This can explain why the usage of displastically changed hips is so frequent. With such hips the contact hip joint stress is higher than with normal hips. They also determined the effect of some radiographic parameters on the contact hip joint stress and thus also on the hip wear. (Abstract truncated at 2000 characters)
Descriptors		HIP PROSTHESIS POLYETHYLENES BIOMECHANICS HIP JOINT WEIGHT-BEARING STRESS, MECHANICAL PROSTHESIS FAILURE