There are some variations in recovery after knee replacement surgery, but as a result of recent improvements in analgesia around the time of surgery, many people go home after three days, or even less.
In fact, people that have had a knee replacement under our care in recent times report a dramatic difference between their experiences recently and experiences that have occurred, say, 10 years ago. There is a much-reduced level of pain, a range of motion is much more easily achieved, and little physiotherapy is required to achieve their final outcome.
This is very much in keeping with modern orthopaedic surgery. It also shows the development of prosthesis, which is now very sophisticated and implanted by computer. Robotic surgery may offer something further, but it is too early to tell and, at the moment, must be regarded as an experimental medium done with great care and supervision.
Of course, there can be variations between individual patients, but most patients these days are surprised by how good their results are.