I had total hip replacement three years ago and did a huge amount of research and consulted with a number of surgeons before undertaking the procedure. The consensus is the running in general is NOT recommended - simply because running causes the prosthesis to wear our much more quickly and the a revision is much more complicated and never as successful.
I know a number of posters have talked about resurfacing - also known as The Birmingham Hip, my only advice on this is to be very careful about undergoing this procedure. Their is much documented evidence about the side effects - such as cobaltism- and now many surgeons will not do this procedure. For example, I met with one of the most respected surgeons for the Illinois Bone and Joint Institute and he refuses to do the procedure any more, and as of when I spoke to him, only one surgeon in the practice was still doing resurfacing.
Finally, for conventional hip replacement, it can either be done - either posterior (back) or anterior (front). Mine was posterior, and whilst very successful this procedure is normally conducted by more mature surgeons!! :-) The newer approach is anterior and is less uncomfortable post op and does not come with some of the movement restrictions that the posterior method does - such as no bending more that 90 degrees etc.
So I consider my IM days long over, but am racing bikes and my biking has never been stronger. So as a case study of one - my endurance running days are over. Hope this help and good luck.
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