Author/Editor		Antolič, V; Iglič, A; Srakar, F; Herman, S; Maček-Lebar, A; Brajnik, D
Title		Transposition of the greater trochanter: a mathematical analysis
Type		članek
Source		In: Middleton J, Pande GN, Williams KR, eds. International symposium on computer methods in biomechanics and biomedical engineering: proceedings. Swansea: Book and journals international,
Publication year		1992
Volume		str. 281-6
Language		eng
Abstract		A biochemical situation after the transposition of the greater trochanter (GT) in superior, inferior, lateral and medial directions respectively, is evaluated for various pelvic shapes using a static 3-dimensional mathematical model of an adult human hip in monopodal support. The vector resultant of the hip muscle forces requried to keep the pelvis levelled (Freq) and the avaliable vector resultant of the hip muscle forces (Fav) are calculated in dependence on the position of the GT, where it is taken into account that the position of the GT affects the muscle lenghts and consequently the available muscle forces wich the muscle can develope are changed. It is calculated that with lateralization of the GT the magnitude of the available resultant hip force (Fav) is increased and the magnitude of the required resultant hip force (Freq) is decreased whereas in medialization Fav is decreased and Freq is increased. In distalization Fav and Freq are increased and in proximalization are both decreased. Trendelenburg sign and/or lurch (T) is expected to be positive when the required resultant hip force exceedes the available one, as for an example in medialization and extreme proximalization of the GT. High pelvic shape is for respect to the T sign, biochemically the most favourable followed by steep, broad and shallow one.
Descriptors		FEMUR PELVIS MODELS, BIOLOGICAL ADULT BIOMECHANICS MUSCLE CONTRACTION