Good evening, @etna. Welcome to Connect. Thank you for presenting your medical issue so succinctly. I have had both knees replaced ( TKR) about ten years apart. As I reflect on what I would call "recommendations" and "expectations", these are the things that come to mind. Please realize that there is no way to know just what might be difficult to handle during post-surgery physical therapy treatment. Do you recall or have a copy of what the surgeon was worried about? If not, I would request a list of the recovery issues you face at your current weight. Since your weight is increasing, I wonder what might have to be added to that list.

Has your daily life changed in the last 18 months? Have you explored how weight loss counseling therapy might be able to help you? I have noticed in the press that there are new medications which are being recommended as being helpful for a critical need to lose weight.

Just to get you started thinking ....... here is a list of TKR post-surgery situations that may be a bit of a struggle with an extra 100 lbs of weight.
......getting into and out of the wheelchair that will be waiting for you post-surgery.
......making sure you can move from the wheelchair to your vehicle.
.......assessing the support you will need to transfer from your car to your bedroom and use the bathroom on your way down the hall.
.......elevate your knee on a foam pillow wedge and apply ice.
....... handling the daily exercises selected to strengthen your new knee and diminish the surgery pain.
.......learning to use a walker or rollator to move within your home.
.......getting up the following day and preparing to go for PT.

I could go on, but I think you will comprehend what will be required. As I write this, I assume you can arrange assistance from a home therapist and caretaker for at least three to four weeks.

Please let me know how your surgeon clarifies the post-surgery demands. I think it is critical to understand and accept the requirements and how you plan to meet them.

May you be safe, protected, and free of inner and outer harm.
Chris