I've had RA since 1979, and it's been in sort of a remission. I take Xeljanz daily and Naproxen when needed. I do have a lot of deformity in all my fingers and knuckles of both hands. I've been taking physical therapy for over a year dealing with back pain due to herniated and bulging disks. My pt also does some hand therapy. Just recently she used the Jamar hand dynamometer which measures force in kg and lbs from 2kg to 5 lbs. I squeeze the instrument as hard as I can to measure strength. A couple hours later I noticed a severe flare on my left wrist which is the weaker hand and wrist. My question is I should have known better that this instrument is difficult for RA patients. How do I politely tell my physical therapist that this tool is not suitable for me? She knows I have RA but may not fully understand the consequences of the gripping causing pain and flares. Thank you so much for replies.