I had both Knees replaced in 2005,6 months between each operation.I came to a stage where my quality of life was awfull.Initialy after each one there is a period of uncomfortable pain,slowly reducing for about 3 months.I started in each case to exercise by walking short distances and slowly increasing them.it is important to build muscle around the replacements so working them is necessary.Bed time was uncomfortable until I bought a large plastic box and cut the ends out to keep the sheets off the wound.Although 77 years of age I can go shooting,tend my large garden and generaly do any thing I wish.Go for it, there is light at the end of the tunnel.