Orthopedic surgeons are always trying to improve the design of artificial joint replacements. Over the past 40 years, many different implant designs have been tried and tested. Some of these designs have worked better than others.
There isn't a specific designer prosthesis that we know of, but you may have heard about gender-specific implants. This is a prosthesis that is made just for a man or a woman. The size of the implant is slightly different to adjust for the anatomical differences between males and females. For example, men have larger femurs (thigh bone) where the implant is inserted.
The width of the bone is also different between the sexes. Women tend to have a narrower side-to-side width at the bottom of the femur. This is the part that forms the upper half of the knee joint. A gender-specific implant is made to accomodate this difference.
Manufacturers of joint implants start with an average size and then build implants that are slightly larger or smaller than average. The gender-specific implants do this too but try to match male and female normal anatomy. The goal is to improve durability and function.
Studies are very limited on the actual benefits of these designer implants. There are no studies showing that gender-specific implants work better than the traditional prostheses. Orthopedic surgeons say that implants already come in many sizes that will fit almost anyone's anatomy.