We need SEPH up in here to give us his medical opinion.
The ankle bone is actually the joining of three unique bones; the tibia, the fibula, and the talus. The part that specifically sticks out in forming the protruding part of the ankle is the fibula. A lot of orthopedic surgeons can work on the ankle region, but majority of patients go see a foot specialist called a podiatrist. The area of the talus (which the two leg bones meet at the ankle) then attaches to a very thick bone in the calcaneus. Anterior of the calcaneus are a bunch of bones making the tarsal (which probably isn't important here). Between the leg and the talus, are a ton of very small, but important ligaments connecting that whole region together. Now Avs did not say it was a sprain, which is what I would consider the 3rd worst compared to a partial or complete tear. Since ligaments are just connective tissue which get absolutely little to zero no blood supply, thus no nutrients/oxygen to heal. Most common type of fractures are in lateral malleolus fracture (fibula) and medial malleolus fracture on the tibia. The main causes for such fractures from what I've been told have been twisting, rolling, tripping, falling, and finally impact. Sounds like, to me, that it was a twisting or rolling action that broke his bone leading to some of the blood vessels also snapping as well. He will be fairly bruised for a good four weeks until the swelling goes down, while it takes a full six to seven to heal the bone (no idea how many weeks are left in the NHL).
Sometimes surgery is a benefit for certain procedures like total knees, hips, and shoulders. But if I was Zadorov, I would hope that it doesn't require surgery since we all know what happened to Forsberg. If the bone is in place, it won't need surgery, but if it was rotated around too much, it might require pins, screws, and plates that could hamper normal extension (which could impact his skating). What we can hope for is that it was a clean break and not a comminuted, greenstick, or impact which can leave bone shards and fragments around the injury (all those have a higher chance for surgery). So far from what we've been told, he's out for the season with an ankle fraction; meaning he should recover 100% as that sounds like the best case news for Zadorov. Now if there is a tweet tomorrow telling us he needs surgery, my concerns will go up due to the ankle being one of the body's complex, crammed, and weakest regions. That's my two cents and I'm not charging this time!
