ANKLE SPRAINS & INSTABILITY
An ankle sprain is an injury to the ligaments that stabilize the ankle and prevent it from rolling or giving way. The ligament damage can be as mild as stretching the tissue or as severe as completely tearing the tissue in half. Fortunately, most patients who have an ankle sprain recover with rest, ice, compression, elevation, anti-inflammatories, bracing, and physical therapy. Once the acute pain begins to resolve, physical therapy can help to strengthen the ankle and improve balance and proprioception for prevention of future sprains. Often patients with complete tearing of their ankle ligaments recover completely and are able to resume normal activities without the need for surgical intervention.
Unfortunately, some individuals who experience a severe sprain or have recurrent sprains may develop laxity and instability of their ankle. This can lead to chronic ankle instability. Ankle instability is a problem most often seen in young patients with multiple sprains who may feel that their ankle is unstable and gives way frequently. Symptoms may include pain, giving way, difficulty walking on uneven ground, cracking and popping, or recurrent sprains. Diagnostically, the physician may be able to shift or subluxate the ankle, which can be indicative of excessive motion and chronic instability. Patients may respond to activity modification, bracing, and physical therapy. If these modalities have been attempted and the chronic instability persists, then an operation may be beneficial. The operation may consist of primary repair of the ankle ligaments, commonly referred to as a Brostrum procedure. Some patients may have insufficient healthy tissue for primary repair or participate activities that put extreme amounts of force on the ligaments. In those patients, the surgeon may use a donor tendon to pass through bone tunnels to recreate and reinforce the torn ligaments to strengthen the repair.
In individuals with recurrent episodes of ankle instability, additional portions of the ankle can become damaged including the articular cartilage surface and the peroneal tendons. For this reason, simultaneous to the ligament repair, the surgeon may perform additional procedures including an ankle arthroscopy to remove inflammatory scar tissue and to address any damage to your articular cartilage. This can include removing loose pieces of cartilage and bone (loose bodies) from your ankle or drilling holes in the cartilage defects (osteochondral defects- OCD). Drilling an OCD to stimulate healing is a procedure known as 'microfracture'. In patients who have already attempted microfracture, or who have a very large OCD, then new products exist to help restore the cartilage defect. Three cartilage products approved by the FDA in the United States are BioCartilage (Arthrex, Naples, FL), Cartiform (Arthrex, Naples, FL) and DeNovo (Zimmer Warsaw, IN). These products are expensive and generally only approved by insurance companies after other procedures such as microfracture have been attempted.
Individuals with recurrent sprains also can develop concomitant peroneal tendon tears. These tears can cause pain on the side of the foot or in the ankle behind the fibula bone. Tears severely limit tendon function, which is important for preventing future ankle sprains. For this reason, the peroneal tendons are usually evaluated and repaired if necessary at the time of an ankle ligament reconstruction.
If you have attempted conservative treatment for chronic ankle instability, but you continue to have pain and giving way, then you may benefit from an operation. Your work-up prior to surgery will include a physical exam, x-rays, and sometimes an MRI to evaluate the tendons, the ligaments, and the articular cartilage. A CT scan is also sometimes necessary to help measure the size of an OCD.
The recovery from ankle instability surgery is variable and dependent on patient characteristics as well as surgical findings. The surgery is generally done on an outpatient basis. You will be discharged with a prescription for pain medicine to help control your pain. Many patients choose to have a nerve block placed prior to discharge to help decrease any discomfort. Much of the time immediately after surgery is spent resting and elevating your leg to decrease swelling. We generally recommend you keep your leg elevated as much as possible during the first week after surgery. The ankle is usually immobilized for 4-6 weeks to promote healing. Crutches, a walker, or a rolling knee scooter can be utilized to aid with mobilization during the first 6 weeks. Typically, between 4-6 weeks following surgery, the cast is changed to a walking boot. Patients wear the boot for about 6 weeks as they gradually transition back to full weight bearing and begin range of motion exercises. Typical office visits are at 2 weeks, 6 weeks, 12 weeks, and then less frequently. Physical Therapy is an important component of recovery from chronic ankle instability surgery and is usually commenced at 6 weeks.