“Loose” or “weak” ankles are unstable or unreliable. They are prone to giving way, often with minimal provocation, and this can be considerably disabling.
Tears affecting the ligaments on the lateral (outer) aspect of the ankle are common, and if they fail to heal during the acute (immediate) post-injury period, an unstable joint can result. Instability is a broad term, and can have a number of causes, but when its the result a problem involving the lateral ligaments its usually because these have healed elongated, or functionally longer than nature intended!
The following discussion relates to people whose instability is a consequence of pathology isolated to their lateral ligament complex.
The basic principle of this operation is the restoration of ligament continuity or integrity, at the correct length!
After six weeks it is not technically possible to perform an end-to-end repair of a ruptured tendon due to retraction of the proximal (top) end of the tendon, the formation of adhesions between the muscle and its sheath and shrinkage of the muscle belly itself. A graft may then need to be used to “bridge” the defect in the tendon in order to restore continuity. This is commonly the adjacent tendon, known as the Flexor Hallucis Longus (FHL), the bender of the middle joint of the great toe. This has a strong muscle which helps to overcome the weakness caused by shrinkage of the calf!
Sometimes, with a long-standing/chronic tendon rupture, extensive scar tissue forms in the tendon defect, although this is elongated, and this can be shortened without the need for a graft of tendon transfer, in order restore tendon continuity.
Following either of these operations, there would need to be a six week post-operative period of ankle splintage and non-weight-bearing on the extremity. It can take some months to recover close to maximum strength.
This means that a simple shortening of either one or both of the ATFL/CFL components of the ligament complex is usually sufficient surgical treatment.
This is typically achieved by elevating the ligament origin(s) from the lateral malleolus, advancing the ligament attachment point and then reattaching it to the bone under tension using small anchors buried within the bone which function as fixation for sutures. There is often excess ligament tissue, which allows for “double-breasting” in order to reinforce the reconstruction.
Some people with long-standing instability, more severe injuries, underlying connective tissue disorders or previous surgery lack sufficient ligament tissue for a conventional reconstruction and require augmentation with a prosthetic device, consisting of artificial fibres which run parallel to the biological reconstruction and are connected to the underlying bones with a different type of buried anchor. These devices are biocompatible and can add extra security to a ligament reconstruction, sometimes allowing for an accelerated recovery process.
Most lateral ligament reconstructions are relatively small operations requiring just a single day in hospital, but the recovery period can be quite long. Its usually possible to commence a return to running and other high impact activities after 3 months, but my protocol involves an initial 2 week period of non-weight-bearing, followed by 4 weeks in a CAM boot, during which time standing and walking on the extremity is permitted. Physiotherapy treatment aimed at rehabilitating joint motion, strength and balance is then commenced.
As with all operations, the relative merits of a lateral ligament reconstruction need to be balanced against the relevant attendant risks and disadvantages.