Thanks for posting your querry.
After reading your dad's symptoms, i feel that the medicines to dissolve stones, have lead to calcium deficiency
and may have developed osteoarthritis
. You need to stop those medicines as Lithotripsy
procedure seems to be a more viable option for him. This is a procedure in which ultrasonic rays are used to dissolve the stones in the kidneys without any side effects as there are no cuts and it is not a surgical procedure.
He must also try to get his sugar levels under control by losing weight and monitoring carbohydrate/fat/sugar consumption. I would recommend you to visit your doctor to understand more about this procedure(lithotripsy).
Meanwhile he may take pain killers to ease of the joint pains