I'm not sure if it's restless leg syndrome, but my knees have been hurting so severely at night my legs have basically been restless, which makes the rest of my body restless.
I get something like that in my thumb. I know what it is thought. The IRA blew up Manchester and fired a piece of brick into the joint. The surgeon got it out but it damaged the bone like arthritis which is getting worse with age.
My cure. A hot water bottle to use as a cushion for mt hand or a thermal glove. I guess the glove is a no, no for knees but maybe a thermal bandage at night will help or make a hot water battle up and place it under your knees.
It may help, it it does its a winner. If not you've gained nothing but lost nothing either