[adrianwaj]

A "Half Round Foam Roller" is indispensable to bring rear-arching flexibility to any part of the spine. Lie on it in bed after spending hours sitting. Have it placed against the lower spine. It can even be used lengthways along the entire spine.

... can also use it while driving.

[LosWochosWeek]

Hmm, not sure how good that is. Pretty sure every fitness guru out there advises against using foam rollers for your lower back. Not sure why tho.

[alexander_singh]

I also had a severe back injury - using a full foam roller can overextend your back and cause further injury. My understanding is a half-circle can just provide some lumbar support if you don't have good lumbar support in your desk chair, etc. I've also been told to roll a towel up and use it for lumbar support or lying on.

[adrianwaj]

I've never had a problem with it - I guess you need to find the right sized one. Also, it's a strong stretch and one can build up to it using a rolled-up towel and use it on all parts of the spine. I just go by feeling.

I actually got mine from a chiro - there must be a precise diameter required for the spine - 14.5cm hard foam.