Diabetic, heavy, bone on bone after 40+ years as a hairdresser, then a geriatrics nurse. She was 72 at the time, and her aunt (who is 4.5 years older) was in the same place (though Auntie's career was teaching, but still, 40+ years of standing.)
They were an almost perfect experiment and control. Both had one knee, then the other; both spent 3 weeks in a rehab hospital after each surgery. For my grandmother, the pain is less but her mobility is iffy now. Auntie (who is now 82) no longer drives (she has hand tremors) but she just finished her first 5K of the season. last year, she did 14 5K or 10K walks and placed 1-5 for her over 75 age category.
The difference is a single factor. Before surgery, Auntie bought a treadmill and a recumbent bicycle. She sold her sofa to make room for the two machines. She also moved her easy chair into a corner where she can't see her TV. In her living room, if one wants to watch TV, one must be on either the treadmill or the bike. After Auntie came home from rehab, she hired a personal trainer to come to her house once a week and call her twice every day -- once to remind her to hit the bike or mill, once to check that she had. The trainer worked with her physical therapist and orthopedic surgeon to keep her progressing. Six months after Auntie's second surgery, she walked her first competitive 5K. She credits her love of HGTV (and this woman REALLY loves her house flipping reality TV.)
My grandmother had good intentions for rehab -- instead of buying the machines, she intended to go to her town's senior center every day. This lasted about two weeks -- good intentions, but then there was a rainy day... And then another, and another. And then she got a cold, and then she had a hair appointment.... And she got out of the groove.
(The other big difference -- auntie has a teacher's pension with amazingly good health benefits on top of Medicare and her widow's SS benefits, including a 50% reimbursement for her trainer. Yay, unions! Gran's retirement income is all investment income, and her supplemental Medicare policy does not reimburse for her trainer.)
Rehab and maintenance are critical after surgery. It's hard to lose fat or rebuild muscle at 60+, so it takes a major commitment. It's incredibly hard to lose weight when exercise is excruciating, and soft tissue loss guarantees pain. Auntie's daily regimen isn't arduous -- she was only walking about 2 mph at first, and she still doesn't go much above 3.5 or 4 -- but it's all about endurance and keeping at it every day.
Both Auntie and Gran have significantly less pain than they did before and that alone is great for their health. Less pain means less inflammation and less stress on their adrenal systems, which means they both sleep better and their sugar and blood pressure is much more stable. Gran's problem now is muscle loss -- she never fully regained what surgery damaged, and she's been losing ground.
If your mom was mine, I'd see if she could maintain 3 months of chair-based (sit & be fit type) exercise with daily reminders.
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