When one rolls over on their ankle, quite often the outside ankle bone, which is the most distal portion of the fibula, will move in such a way that even after ligament and tendon strains/sprains have healed, that outside ankle bone is no longer able to sit in proper alignment with the other ankle bones.

This can easily be remedied with a few visits to an osteopath, a chiropractor or PT. Some other physical therapists may also offer this type of therapy. Just make sure that it is someone who knows how to manipulate and realign peripheral joints.
The practitioner will use gentle techniques to re-align the ankle bones.

This may be the most important type of therapy to have done if one wishes to obtain a full recovery and prevent future sprains; as the ankle will not usually re-align by itself (without manipulation), yet this form of therapy is often overlooked.

Not having the ankle re-aligned is often the reason why some find that the ankle "is never the same again" or "didn't heal completely" after a sprain.

Ankle sprain and fibula treatment:
https://www.youtube.com/watch?v=gd82b7WM4to

Hope that your hubby's ankle heals up quickly and fully.

With love, Erika