What are the ligaments of the ankle?
The ankle is a hinge joint between the leg and the foot, and allows up and down movement. The bones of the leg (tibia and fibula) form a slot, and the talus bone of the foot fits between them. The talus is held to the tibia and fibula by strong bands of tissue called ligaments. Each ligament is made of many strands or fibres of a material called collagen, which is extremely strong.
The ligament on the inside of the ankle (the deltoid ligament) has two layers; the deepest one is most important. This ligament is mainly torn in association with severe fractures of the ankle bones. Sporting injuries of this ligament are rare.
The ligament on the outside of the ankle (lateral ligament) is made up of three separate bands: one at the front (anterior talo-fibular ligament), one in the middle (calcaneo-fibular ligament) and one at the back (posterior talo-fibular ligament). The front and middle bands are the ligaments injured in a sprain.
The tibia and fibula form a joint between themselves just above the ankle. This also has strong ligaments, one at the front and one at the back (tibio-fibular ligaments). The ligament at the front is involved in 10-20% of ankle sprains; this injury is important, as it takes a long time to heal, although it usually heals without the need for surgical treatment.
How do the ankle ligaments get injured?
Most ankle ligament injuries are caused when the foot twists inwards. All of the body’s weight is then placed on the lateral ankle ligaments. The anterior and middle fibres of the ankle stretch or tear a in sprain or strain of the ankle. 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 cartilage lining 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.
What should I do if I sprain my ankle?
Most ankle sprains are fairly minor injuries, which will get better with simple self-care treatment. The word RICE reminds us of the basic treatment of a sprained joint:
Rest – take the weight off the injured joint as much as possible for a day or two
Ice – an ice pack (a small bag of frozen peas is ideal) can be applied for 10-15 minutes, 3-4 times a day to reduce swelling
Compression – a support bandage or strapping will help to reduce the swelling
Elevation – resting with the ankle above the height of the body will allow swelling to drain away into the bloodstream
Although a couple of days rest is useful, it is best to start taking some weight on the injured ankle reasonably soon after injury, usually within 2-3 days. Also start to exercise and stretch the injured ankle as soon as possible after the injury.
Normally a sprained ankle will recover within 6-8 weeks, although it may tend to swell for a few months longer.
Will I keep having trouble with my ankle?
The majority of ankle injuries get better completely and cause no long-term problems. Unfortunately occasionally there is permanent damage to the ankle. The ligaments may fail to heal properly and become weak – leading to ankle instability, or there may be damage to the joint itself or some other structure nearby – leading to ankle pain and swelling.
What can be done about ankle instability?
Most people with ankle ligament instability have damage to the ligaments, which can be overcome with appropriate physiotherapy rehabilitation. The rehabilitation concentrates on two main areas. Firstly strengthening the muscles around the outside of the ankle. Secondly, by improving your balance. This may require the use of specialised equipment such as a “wobble-board,” or a “trampette.” However, similar exercises can be practised at home by using a cushion, or a piece of sponge. Your physiotherapist will help you with this.
If your ankle or Achilles tendon are stiff, you will also be shown exercises to stretch these. If your foot shape makes you prone to extra stress on the ankle ligaments, a moulded insole may be advised for your shoe to reduce these stresses.
Most people will find their ankle much more stable and comfortable after physiotherapy. However, in some people problems continue. At this point the opinion of an orthopaedic foot and ankle surgeon may be helpful, and your general practitioner may refer you for further treatment. The surgeon may also suggest an exploratory operation on your ankle (arthroscopy) to check on the state of the joint. If these tests suggest weakness of the ankle ligaments, an operation may be advised.