Ankle Stabilization Overview
Ankle function depends in part on stability from the various ligaments and tendons which surround the joint. Single or repeated injuries can damage one or more of these structures, and if persistent instability results, ankle stabilization surgery may be beneficial. It is performed as an outpatient procedure, and is followed by a period of splinting and crutches, then a fracture boot for early mobilization, and finally a period of functional bracing and physiotherapy.
Ankle Stabilization Details
Ankle stability is dependent on bone alignment, ligament integrity, and tendon function. The most common ankle stability pattern results from repeated ligament sprains or “going over” of the ankle. Sometimes these are simple sprains, but sometimes there can be significant ligament tearing, accompanied by swelling and bruising. This typically affects the ligaments on the outer (lateral) aspect of the ankle, which become stretched and fail to resume their normal tension. This makes the instability episodes more frequent and disabling.
Ankle bracing can sometimes be effective to treat the problem, whether for sports, aggressive activities, or even for day to day use. If bracing is ineffective or unsatisfactory, lateral ligament stabilization surgery may be indicated. An MRI may help to make the diagnosis but often physical examination alone is sufficient. One or both of the main lateral ankle ligaments may be involved. Sometimes there is additional ankle joint cartilage damage.
Ankle stabilization surgery is performed as a day surgery procedure under spinal or general anaesthesia. A curved 3 inch incision at the outside of the ankle is used to access the damaged tissue. The torn or stretched ligament ends are identified, tensioned, and reattached to the lateral ankle bone (fibula) with small anchors. If there is additional cartilage damage inside the ankle, this is treated arthroscopically at the same surgery. A partial cast is applied to maintain the safe position of the ankle after surgery, and crutches are used for the first 6 weeks.
At about 6 weeks the patient can commence walking in a fracture boot. Gentle range of motion exercises are initiated and physiotherapy is arranged. At about the 3 month mark, the fracture boot is discontinued and a functional brace worn inside the shoe is used for the next month or two. This rehabilitation protocol is lengthy but essential for a satisfactory outcome, as ligaments take a considerable time to heal and the supporting tissues and muscles must be restored to full strength to prevent recurrence.
Potential complications include anaesthetic risks, infection, nerve injury, or persistence of instability. If the procedure is unsuccessful or the instability recurs, a ligament grafting procedure may need to be performed as a revision surgery.