At least, for 80% or so of the hedgehogs out there, litter training can be very effective.
Training is quite basic. First, set up a rectangular litterpan with a small lip (a cookie tray works great) under, or in front of, your wheel. Use a different type of litter than bedding, such as Yesterday’s News in the litterpan.
Your hedgehog will instinctively ‘potty on the run’. Any that comes off the wheel will land in the litterpan, doing most of the training for you. Any ‘mistakes’ made elsewhere in the cage should be picked up and placed in the litterpan. This will cause your hedgehog to quickly realize where he/she is supposed to potty.
While some hedgehogs will remain stubborn and seemingly not care, *most* will start to only potty in the litterpan (other than their wheel).
I have seen a number of hedgehogs now, who using this method, have even taken it to the next level and ONLY potty in the box, leaving their wheel clean!
Remember that most hedgehogs go home with you when they are still a baby, and do not have regular control over their bodily habits yet, so be patient!
Try it, it’s SO worth it for both of you!