My first total hip replacement was 7.5 years ago at age 49. At that time I was riding the bike outdoors by the fifth post operative week. I just had the other hip replaced 18 days ago (bilateral congenital hip dysplasia). Both surgeries were posterolateral approach. I will be 57 in about 2 months. I now have an indoor spinning bike (Stages SC3) and have been riding indoors since post op day 3, and I am now up to an hour with maximum force of about 500 watts according to the power meter. I use the XERT workout player indoors to train.
Today, I went for an outdoor ride of about 40 minutes in the neighborhood at about 14.5 mph. Piece of cake. I put some pedal platforms on my Look Keo pedals and rode with running shoes, so I didn't have to worry about unclipping, but I don't think it will be a problem. Surgeon said just be careful. I hit 400 watts, less than half of my power max before surgery, but I didn't have cleats, and I am in no hurry to mess things up. I go back to work on post op day 21 in just 3 days. I am almost normal in my gait. I think it helped that I rode 4850 outdoor miles in the last 11 1/2 months.
Search pedal plate Netherlands for the pedal adapters. My wife wants me to use them, but I think they will come in handy in the summer riding to the swimming pool. Happy Holidays!