Hi David,
Sorry to hear that you are an arthritis sufferer - I know it can be very painful.
I have a friend who is a fellow sufferer that sold a Manfrotto pistol head because he couldn't use it. In order to make the head stable and prevent creep due to the weight of body and lens it was necessary to tighten the grip tensioner quite a bit. This resulted in the trigger being very hard to squeeze in order to adjust his view and when it did release the balance was all wrong - the heavy body and lens is above your hand - causing the camera to tip forwards. Very painful for him. Indeed on bad days he was unable to stop the forward tilt and ended up picking both tripod and camera out of the dirt more than once.
His solution was to buy a 3-way head and have "T" pieces made to fit the ends of the adjustment grips. These screwed on to threads cut onto the ends of the grip bars. He finds this very easy to use with minimal pain.
Just a suggestion :shrug: