Method for designing a bone morphology based hip system

摘要

A method of designing a group of femoral implants from three-dimensional images of femurs from a patient population greater than 100. A boundary between cortical and cancellous bone is defined in each of the images. A longitudinal axis of the femur is defined centered within the boundary. The width of the boundary is measured in a direction perpendicular to the axis at multiple cross-sections along the longitudinal axis spaced less than 20 mm. At least five (5) different size implants for implantation in a noncortical bone area of the femur are designed based on the measured widths. At least one area of the proximal femoral component boundary is designed where the implant outer surface is sized to be within 2 mm of the cortical bone. The proximal dimensions of the at least five implants are sized to provide the fit within 2 mm in 95% of the femurs from the population.

主权项

1. A method of designing a group of femoral implants for implantation into a population of patients comprising:
obtaining three-dimensional images of femur from each patient of a population of patients numbering greater than 100; defining a boundary between cortical and cancellous bone in each of the images; defining a longitudinal axis of the femur geometrically centered within the boundary; measuring the width of the boundary in a direction perpendicular to the axis at multiple cross-sections along the longitudinal axis spaced less than 20 mm apart along the longitudinal axis; defining at least five (5) different size implants for implantation in a noncortical bone area of the bone based on the measured widths; defining at least one area of the proximal femoral boundary where the implant outer surface is sized to be within 2 mm on a medial side of the cortical bone; and revising proximal dimensions of the at least five different size implants to provide the fit of the implants within 2 mm on the medial side in 95% of the femurs from the population further comprising aggregating cross-sectional data from the images to create an average stem profile for each of the at least five different size implants prior to revising the size of each stem to provide the fit within 2 mm of cortical bone proximally.