Author/Editor		Stražar, Klemen
Title		Primerjava omajanja izoelastičnih brezcementnih in kovinskih cementnih femoralnih debel s histološko in rentgensko analizo
Type		monografija
Place		Ljubljana
Publisher		Medicinska fakulteta
Publication year		2001
Volume		str. 64
Language		slo
Abstract		Backgrounds: The purpose of isoelastic cementless stem coated by polyacetal was to prolong the period between the insertion and the aseptic loosening of the hip prosthesis. Lower elastic modulus was supposed to ensure transfer of stresses on the bone in a more physiological way avoiding the occurrence of osteoatrophy, which is the problem of stiff metal stems. 'Fhe second but clear advantage of the isoelastic stem was fixation of the stem without using a cement. Wear particles of cement are linked up to a high incidence of aseptic inflammation and osteolysis. Against the expectation the time between the insertion and the loosening of isoelastic prostheses were shorter in comparison to the duration of prostheses of any other kind. The exact causes for this are still not known. The purpose: By the histological and the radiological analyses we wanted to find factors responsible for an early aseptic loosening of isoelastic cementless stems. Oil-O-red technique was used to identify polymere wear particles and to evaluate the value of this method. We wanted to find out if different elastic modulus influences on the rapidity and the direction of polyethylene cups. Patients and methods: From February 1997 to January 2001 results of the histological and the radiological analyses of 11 loosened isoelastic and 11 loosened cemented stems (a control group) were compared. Comparing results of semikvantitative analysis of histological preparations in group af loosened isoelastic stems with results in the group of loosened cemented stems, diffences in histological criteria (inflammatory cells, wear particles, degeneration of tissue) were observed.
Descriptors		HIP PROSTHESIS PROSTHESIS FAILURE HIP JOINT POLYETHYLENES GRANULOMA, FOREIGN-BODY WEIGHT-BEARING POLYMETHACRYLIC ACIDS FOREIGN-BODY REACTION MACROPHAGES