The ankle joint is formed by the talus, the main ankle bone, the tibia (the shin bone) and the fibula (the small bone on the outside of the lower leg). The most common ligaments to be injured are those on the outside of the ankle. The ligaments on the outer part of the ankle (the lateral ligaments) are divided into three sections, one at the front, one to the side and one towards the back. (Figure 1). On the inner side of the ankle, (the medial side) the ligament has two parts, although the medial ligament is much less commonly injured. There are also other ligaments connecting adjacent bones that can occasionally be injured in more severe injuries.
Figure 1 – The Ankle
What is an Ankle Sprain?
A sprain of the lateral ligaments usually occurs as a result of a twisting injury with the sole of the foot pointing inwards. The ligaments can either be stretched or torn. They will occasionally pull away from the bone with a small fragment of bone attached to them which may be visible on the x-ray. If the force of the injury is significant, then this may also cause the bones to fracture or in the most severe cases, for the ankle joint itself to dislocate. In the most severe injuries, other structures around the ankle can be injured. These include the cartilage lining of the joint (an osteochondral injury), the tendons around the outside of the ankle known as the peroneal tendons, or the nerves around the front and side of the ankle.
Treatment of Ankle Sprains
The vast majority of ankle sprains will settle without any surgery. We would suggest rest for a short period to allow the swelling and inflammation to settle. Ice placed intermittently over the swollen area may help to reduce the swelling. Please note that ice should not be placed directly on the skin and we would recommend wrapping the ice in a towel or protective sheet before placing it on the swollen area. High elevation, which involves sitting with the foot at or above the level of the heart, will also assist the swelling to reduce. Physiotherapy is important in the rehabilitation from ankle sprains. Mr Taylor will recommend physiotherapists that he works closely with. In general symptoms will begin to settle within a week or two and we would expect a return to all but full activity within 6 weeks.
Long Term Problems After Ankle Sprain
Occasionally, symptoms in the ankle will fail to settle despite the appropriate treatment. If within 3 to 6 months the symptoms have not settled, then we would suggest seeking medical advice. Symptoms after an ankle sprain can generally be divided into instability problems or pain problems. Instability, or a feeling of "giving way" of the ankle, often occurs as a result of injury to the ligaments. If the ligaments either fail to heal or heal elongated, then they may not provide sufficient stability to the ankle. This will often cause a feeling of instability, or actual giving way of the ankle and is often symptomatic when walking on uneven ground.
Pain that persists after an ankle sprain can be due to a number of causes. The most common causes include osteochondral lesions (injury to the cartilage and bone of the ankle joint), peroneal tendon tears, ongoing inflammation in the ankle (known as synovitis), injury to the nerves and other rarer causes of ankle pain.
Treatment of Chronic Instability After an Ankle Sprain
If, despite extensive physiotherapy, symptoms have failed to settle then it may be appropriate to consider surgical stabilisation of the ankle joint. This usually involves a direct repair of the ligaments on the outside of the ankle and re-enforcement of these, a procedure known as a Brostrum procedure. Mr Taylor will discuss the details of any proposed surgery with you, as well as the pros and cons of surgery, when you attend for your outpatient consultation.
Treatment of Chronic Pain After an Ankle Sprain
Treatment of pain will of course depend on the cause. Often, patients with chronic pain after ankle sprain are investigated with an MRI scan. This excellent investigation allows a very accurate assessment of the ankle joint and surrounding structures to be made and any possible injuries of the ankle to be identified. If inflammation or damage to the cartilage has been identified then it may be appropriate to consider keyhole surgery, known as arthroscopy, to settle things.