FIELD: medicine.SUBSTANCE: method of optimising geometry of a femoral stem of a hip joint prosthesis, wherein the femoral stem comprises a neck and an anchoring blade that is attached to the neck and that tapers towards a distal end with a lateral narrow side comprising a distal straight portion and a proximal arcuate portion corresponding to a curve, wherein the transition between the said distal straight portion and the said proximal arcuate portion occurs at an outer lateral point. As per the first variant the method comprises a means of optimizing the profile of the curve of the said proximal arcuate portion by a process of iterative modelling steps using a series of curves each defined by a path traced by the outer lateral point on withdrawal of a profile of the stem from a cavity of complementary shape to the stem. Femoral stem of a hip joint prosthesis produced by this method has a geometry optimized in accordance to the described method of the first variant. Method of optimizing the geometry of a femoral stem of a hip joint prosthesis, wherein the femoral stem comprises a neck and an anchoring blade that is attached to the neck and that tapers towards a distal end with a lateral narrow side comprising a distal straight portion and a proximal arcuate portion corresponding to a curve, wherein the transition between the distal straight portion and the proximal arcuate portion occurs at an outer lateral point. As per the second variant the method comprises a means of optimizing the profile of the curve of said proximal arcuate portion by a process of iterative modelling steps using a series of curves each defined by a path traced by the outer lateral point on withdrawal of a profile of the stem from a cavity of complementary shape to the stem. Femoral stem of a hip joint prosthesis as per the second variant has a geometry optimized in accordance to the described method of the second variant. Hip joint prosthesis system for use in the implantation of said femoral
