The typical ankle sprain involves a partially or fully torn ligament along the inside (medial) or outside (lateral ankle. With severe sprains, there can also be something called osteochondral lesion of the talus (OLT). The talus is a bone that sits just above the calcaneus (heel bone).
The term osteochondral tell us that the joint cartilage (chondral) and bone (oste) just underneath the cartilage have been damaged. With some of the more severe osteochondral lesions (OCLs), there is a piece of cartilage with the bone attached that is loose in the joint causing further problems. Anytime there’s a problem inside the joint, it’s referred to as an intraarticular lesion.
The problem with a severe ankle sprain that leads to osteochondral lesion and joint instability is that these are two separate problems requiring different surgical techniques and different rehab approaches. They aren’t usually both treated at the same time. Surgery is done in two phases, which is why it’s called a staged procedure.
In the first operation (stage) the surgeon uses an arthroscope to look inside the joint and find any damage to the joint. Osteochondral lesions are removed and the joint surface is smoothed down. Rehab begins right away with weight-bearing allowed to help smooth the joint surface and stimulate healing.
Once osteochondral lesion is taken care of, the surgeon repairs any damage done to the ligaments. If the tissue is too damaged to repair, then a piece of tendon from another muscle can be used as a graft to replace the torn ligament. After a ligament repair or reconstructive surgery the patients are in a cast to protect the healing tissue. Unlike rehab for the osteochondral lesion that responds better with immediate weight-bearing, healing ligaments or grafts require uninterrupted quiet without movement.
The cast is kept on for four to six weeks and then a removable walker boot or splint is worn for a bit longer. At this point, the physical therapist can start gentle range-of-motion exercises with you. You will gradually put allowed to put full weight on that ankle. Pool therapy may be used before beginning land exercises and especially before beginning high-impact athletic activities.
Some surgeons are experimenting with ways to do both procedures during the same operation. A combination of short-term casting followed by splinting and rehab is being investigated. The idea is to find a happy medium between stimulation for the cartilage repair and stability for the ligamentous repair or reconstruction. Until this has been researched fully, most orthopedic surgeons will continue making this a two-part or staged procedure.