Ankle instability is a condition causing recurrent giving way of the ankle, usually into inversion (when the ankle rolls inward).
Ankle instability develops after repeated ankle sprains that have not been treated or rehabilitated appropriately, though on occasion can be linked to ligament laxity or soft tissue conditions causing your ligaments to be stretchier than normal, such as Ehler’s Danlos.
When someone twists their ankle, the first ligaments to tear are the Anterior Talofibular, then the Calcaneofibular, usually in that order. Occasionally small pieces of bone may be torn off with the ligaments. In a few cases, a twisting force on the ankle may cause other damage.
The bones around the ankle may be broken, a piece of the joint surface inside the ankle may be chipped off, ligaments connecting other bones in the foot may be sprained or torn, or the tendons around the ankle may be damaged.
The tear can be partial (grades I or II) or complete (grade III) which can be overcome with appropriate physiotherapy rehabilitation.
This condition can be particularly debilitating as you gradually lose trust and confidence in your ankle. You may feel particularly unstable initially on uneven ground or when playing sports, progressing to instability even when doing normal activities of daily living. Each ankle sprain will progressively weaken your ligaments, resulting in greater loss of confidence and increased instability.
Diagnosis
This instability can clinically be proven when your surgeon examines your ankle and notices increased tilt of the talus (ball joint of the ankle) and also increased laxity to pulling your ankle anteriorly (anterior drawer).
This can be further confirmed by an ultrasound that reveals chronic tears or absence of the ligaments that stabilise the ankle. On occasion your surgeon may order an MRI to exclude any other problems within the ankle. Repetitive sprains to the ankle can sometimes cause damage to the cartilage within the ankle joint, called talar osteochondral defects and it is important to identify these if surgery is required, as these can be addressed simultaneously.
Treatment
Treatment for chronic ankle instability is the same as an acute ankle sprain, which in the initial period of a sprain is still RICE (Rest Ice Compression Elevation), then progressing to physiotherapy to strengthen and improve proprioception and balance in the ankle. Wearing a brace can also help to increase stability and proprioception to the ankle.
Occasionally your surgeon will recommend surgery when non-operative measures have failed or there is other additional damage within the ankle requiring attention.
Surgery
Stabilizing the ligaments is usually done through an open approach on the lateral (outside) aspect of your ankle, where your surgeon will identify the torn or lax ligaments, and tighten and repair them up to the fibula, using sutures, or anchors – which are special screw-like devices with sutures within them.
You may be placed into a plaster cast or walking case while the ligaments repair themselves, and there may be a period of non-weight bearing to allow the wound to heal. After that, you are encouraged to come out of your walking case/plaster to allow gentle range of motion of the ankle.
Once the ligaments are healed, ongoing physical therapy is encouraged to continue strengthening the ligaments and to obtain adequate range in the ankle.
If you are experiencing problems with chronic or recurrent ankle instability, it is vital that you visit an orthopedic specialist to be properly assessed. This problem can frequently be fixed through non-surgical means, like proper rest, stabilization and physical therapy. If, in the infrequent chance that you require surgery to fix the problem, timely treatment can be vital to your continued health, safety and well-being.