I've developed severe arthritis and my knees are stiff, but I still love to get out on the water. Does anyone have suggestions for getting in and out of a kayak without ending up in the water?

This site seems to have a wealth of information on adaptive paddling. If you don’t find the answer to your exact situation, the Q&A person’s page should answer your specific question.

The simplest and probably the best solution would be to find a paddling buddy that will help you in and out of the boat. Also a buddy will help you transport your kayak. It’s also safer for you to paddle with a buddy. If possible join a paddling club. I’m a member of two paddling clubs (outrigger canoe and dragon boat) and I have no problem at all finding paddling buddies that seem ready to paddle whenever I am.

Good luck!

Are you equipped to build a prototype? Perhaps you could design one with a hinged portion just forward of the seat which can be latched with a quick released for emergency. With an enlarged opening, you could possibly have a better chance.