If the injury is muscle tissue related it will help. If it is connective tissue, tendons/ligaments, most every joint or anything collagen based (so like every sport related injury) unfortunately it won't do much. It will however help get over any muscular atrophy associated with disuse due to injury, just make sure not to push too hard.
In my anecdotal experience, I had some relief from injury from ostarine, I am not sure if it actually accelerated the healing process, but it certainly made me feel better and allowed me greater use and range of motion while I was injured, which could have helped my recovery.