how long for a sprained ankle to heal?
Grade 3 Sprain. A grade 3 sprain is the most serious injury with the longest healing/recovery time. A sprain of this severity can easily take 8 to 12 weeks or even longer to heal completely. Physicians usually immobilize the joint and prescribe physical therapy, just as with a grade 2 sprain. However, the immobilization period is longer, as is the physical-therapy program.