That's a tough one. The first thing that comes to mind is teaching.
A good friend of mine recently injured his back. He owns two restaurants here in town. He turned over the day to day operations to his brother (also a chef) and took a job as a buyer for a regional supplier.
You could move to be a dining room supervisor possibly? I see a lot of exec chefs with that dual role? It just means you would be dealing with more meetings and emails but defiantly could come on the line to expedite depending on how severe your condition is?