Having arthritis is bad, and so is having to shoot someone in the face. God forbid you experience both of these situations at the same time.
In case you do, certified NRA instructor Matthew Carmel has developed the Palm Pistol, "an ergonomically novel handgun designed for seniors, disabled and others with limited manual dexterity."
The Palm Pistol is an ergonomically innovative single shot double action only defensive firearm chambered in 9mm that may be fired using either hand without regard to orientation of the stock. Suited for home defense, concealed carry or as a backup gun. It is also ideal for seniors, disabled or others who may have limited strength or manual dexterity. Using the thumb instead of the index finger for firing, it significantly reduces muzzle drift, one of the principle causes of inaccurate targeting. Point and shoot couldn't be easier.
Just because bystanders are screaming doesn't mean your joints should be.