Hi Jennifer;

First of all, I am sorry that your son has to suffer like that on a daily basis. You're a good mother to seek out the best for him.

The good news is that there are lots of tools out there to help with daily living tasks for both the young and old who suffer from arthritis.

The main problem (besides fatique) is the dexterity required for pulling zippers, buttoning buttons and tying shoes. Swollen and painful joints can also make for a frustrating time doing the simplest of tasks. 

Here are a few examples of dressing tools that have been invented to help those suffering from arthritis:

 
In addition to dressing tasks, people suffering from arthritis symptoms can also have trouble doing other daily living tasks, like turning keys, switching on lamps and tasks that involve gripping, like pulling plugs and holding a book.

In Rehabmart's arthritis category, you'll find over 300 products we've identified as being helpful for arthritis, including a book holder, plug puller, oversized lamp switch and a leveraged key turner.

Finally, I've had many clients with arthritis tell me that a hot wax treatment called a "paraffin bath" was very effective at releaving some of the stiffness and soreness associated with their arthritis. You may have seen these before at the local nail care salon, where people use paraffin to soften their hands. (See Paraffin Baths)

Even though paraffin baths don't require a prescriptions, be sure to check with your doctor first, as he/she is the only one qualified to know your son's condition and can monitor for any adverse effects.
 
Thanks again for the question, Jennifer - I hope this helps give you a few ideas for your son. We wish both him and you the best!