Author/Editor		Ivanovski, Matic; List, Ivo
Title		Pomen kolčnega sklepnega tlaka pri nastanku nekroze kolčne glavice
Type		monografija
Place		Ljubljana
Publisher		Medicinska fakulteta
Publication year		2006
Volume		str. 55
Language		slo
Abstract		Backgroud Aseptic necrosis of the femoral head (AN) is a disease of the hip which is caused by the ishemy of the femoral head. It is connected to the bone and cartilage trauma, chronic alchoholism, corticosteroid therapy, pregnancy, sickle-cell anemia and other dieseases leading to disorder of vascularisation of the femoral head. Causes of AN are heterogeneous while underlying mechanisms are not completely understood. The mechanical hypothesis proposes that stresses in the femoral head and within the hip cartilage are important for the onset and development of AN. The existing descriptions of the hip stresses were made mostly by the finite element method, however, according to our knowledge, there is no reported biomechanical study of AN considering a larger population of hips with AN. Aim It was our aim to: - determine the role of the contact hip stress in the onset of AN - upgrade the HIPSTRESS method for determining the contact hip stress by taking into account changes in the load bearing capacity due to AN - use the new method to determine changes in contact hip stress due to development of necrotic lesion Hypothesis Hips with increased risk for onset of AN have biomechanically less favourable distribution of contact hip stress on the load-bearing area than normal hips. Meanining that in these heaps the functional angle of the load bearing area (VF) is smaller, the normalized index of stress gradient (Gp/WB) is higher, the position of stress pole (O) is more lateral and the normalized peak contact hip stress (pmax/WB) is higher than in normal hips. With developement of nectrotic lesion the contact hip stress changes, as to become biomechanically less favourable. (Abstract truncated at 2000 characters)
Descriptors		FEMUR HEAD NECROSIS STRESS, MECHANICAL HIP WEIGHT-BEARING MODELS, THEORETICAL