What the doc said -night splint. The Strassborg sock never did much for me. If you need a large, shoot me a PM with you addy and I will send it your way.
Tried several night splints over the last two years. Started with the 3M Futuro…but that holds the foot from the top / front and did not like the pressure it put under the ball of my foot.
The I used one from Brown which had an overall softer feel and used webbing straps crossing to hold the ankel @ 90 degrees. SOmewhat more comfortable than the 3M, but had a tough time holding the ankle @ 90*. This was partly due to having skinny legs and the straps and not ebing able to get the straps tight enough.
This is the model I am using now…I think it is from Swede O. Brown makes a similar model. Picked it up at a local triathlon expo. Obviously more bulky than the other two units which makes sleeping a bit more challneging, but it gives me the best overall support. It is adjustable so I can vary the angle that I hold my ankle at night. SO far, I have been pretty happy with it.