If the fear is getting up at night, get one of these Smart cordless bed exiting monitoring system Cordless weight sensing pad It comes with sensor that chimes 100 yds away low medium or high chime sound Put it where her shoulders are near her pillow and when she sits up the chime rings Then you can get up and help her. No wires to tangle.
What equipment do you have for Mom. Does she have a good cane or walker? Has she been evaluated by physical therapy for possible rehab work? Is this balance AND knees or just the knees? What tests were done on the knees as far as xrays and what are the results. Have you tried a bedside commode well secured? Is this new or worsening of things ongoing? So sorry there is more to deal with. I am guessing your Mom is living with you.
Smart cordless bed exiting monitoring system
Cordless weight sensing pad
It comes with sensor that chimes 100 yds away
low medium or high chime sound
Put it where her shoulders are near her pillow and when she sits up the chime rings
Then you can get up and help her.
No wires to tangle.
Best wishes to you and your mom.