IMPROVED HIP JOINT PROSTHESIS Russian patent published in 2016 - IPC A61F2/30 A61F2/36 A61B17/16 

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 stem into a femur as per the first variant has a femoral stem with the geometry optimized using the described method of the first variant and a rasp made with the possibility of making a cavity in the femur and the proximal arcuate portion with the profile corresponding to the proximal portion of the anchorage blade of the femoral stem. Hip joint prosthesis system for use in the implantation of said femoral stem into a femur as per the second variant has a femoral stem with the geometry optimized using the described method of the second variant and a rasp made with the possibility of making a cavity in the femur and the proximal arcuate portion with the profile corresponding to the proximal portion of the anchorage blade of the femoral stem.

EFFECT: inventions ensure the preservation of as much bone tissue in the area of the greater trochanter as possible and a minimal invasive surgical procedure.

23 cl, 7 dwg