Every person is different. Your PT is the most important thing for recovery. Do the exercises as directed. Make it your job. I was the poster child for TKR. I was released from PT and the doctor at seven weeks and was hiking the Superstition Mountains in AZ at 10 weeks. It is now my strong knee. After surgery, my back quit hurting as did my other knee. Didn't realize how I had twisted myself to compensate for the bum knee.
For those looking at TKR don't put it off too long. If you are overweight, loose some pounds. After surgery, go to the gym every day and ride a bike. Elevate, ice and anti inflammatories. Most of all get off the narcotics asap. They will make you stupid, lazy and constipated! I was off everything except ice and Tylenol in three days when I realized the post surgical pain was less than the knee pain before surgery.
TKR is like everything. I seems we hear horror stories and not the vast majority of successes.