What is an Achilles Tendon?
The Achilles tendon is the large cord-like structure that you can feel at the back of your ankle. This tendon is the thickest and strongest in the body, and is essential to walking and running.
It connects the powerful calf muscles (gastrocnemius and soleus) to your heel bone (the calcaneum). When you tense your calf muscles, your Achilles tendon tightens, pulling your heel up towards your body, and causing your foot to point down, like a ballerina. This movement is called plantar flexion, and is the movement that pushes your leg away from the ground in walking and running (‘toe-off’ phase).
When you walk, run, jump and do most other movements involving your ankle your Achilles takes on significant stress to support your weight. In addition, the Achilles tendon does not have an entirely straight course, but instead spirals slightly, producing an area vulnerable to fraying and strain. This area – approximately 3-4cm above your heel – is often the site of tears.
Over stretching and repetitive strain can result in the Achilles tendon tearing (rupture). This can be a partial or full thickness rupture, where ends of the tendon are separated completely from each other. Ruptures of the Achilles tend to occur most commonly in people playing recreational sports in their 40s and 50s, however, it can occur at any age. Often, before the tendon tears completely, people report pain and trouble with the tendon as fibres in the ‘cord’ fray one by one.
If you have an Achilles tendon rupture, you might feel a pop or snap, followed by an immediate sharp pain in the back of your ankle and calf. People often describe this as similar to ‘being kicked’.
Ruptures can be treated without an operation in a plaster cast or special brace, or with surgery (see Repair of a Ruptured Achilles Tendon).
As the tendon takes a long time to heal, you may notice significant weakness & stiffness in your leg after weeks of keeping it still. As a result, many people require physiotherapy to rebuild the muscle and regain movement in the joints, and even to relearn how to walk correctly (gait retraining).
Symptoms
Signs and symptoms of an Achilles tendon rupture include:
- Sudden, severe pain along the Achilles tendon with a pop or snap feeling. This can happen without warning or can occur when jumping or landing.
- Swelling and bruising behind the ankle. It is sometimes possible to feel a lump or gap in the tendon.
- Inability to weight bear, especially inability to stand on toes.
Occasionally, there is no pain at all and difficulty using the ankle and walking is the only symptom.
Causes
Your Achilles tendon helps you point your foot downward, rise on your toes and push off your foot as you walk. You rely on it virtually every time you move your foot.
In most cases, ruptures of the Achilles tendon occur at a spot on the tendon that receives less blood flow. This may weaken that section of the tendon, which also tends to gradually wear down with age.
Sudden stressed on an already irritated tendon can cause it to rupture. Common examples include:
- Occasional or increased participation in recreational sports
- Falling from a height
- Stepping into a hole
Risk Factors
- Certain sports. Overuse in people playing sports, running etc. People who have a history of running for many years are especially at risk
- Training. Changes in training – a sudden change in a training regime increases the risk of getting a rupture
- Deformities. Congenital deformities in the foot, including decreased blood supply. In some people there is an association between having slightly mal-aligned bones and getting an Achilles rupture. There is also some potential links between having a slightly compromised blood supply to the tendon and injury. This is partly because the tendon does not have a direct blood supply, but instead receives nutrients from it’s tube-like casing (‘paratenon’). Areas of the tendon in direct contact with the paratenon are usually well supplied with nutrients from the blood, whereas the deepest, central parts of the cord are most vulnerable to losing nutrient supply if the person has a slightly compromised blood supply. These are however both less important than overusing the tendon.
- Medications. There is some potential links between certain medications – like steroids, hormone replacement therapy, some antibiotics – as well as some conditions like high blood pressure or obesity with Achilles tendon rupture.
Investigations
There are a number of tests that can be used to diagnose an Achilles tendon rupture.
- Ultrasound. For severe ruptures, ultrasound is useful – it shows the separation of ends to the tendon quite well, and is easily accessible in the hospital as well as relatively low risk.
- MRI– it may be necessary to take an MRI of the affected ankle to see subtle or partial tears.
Complications
Ruptures can potentially lead to a number of problems including:
- long term pain
- weakness of the ankle
- trouble walking and jumping
In addition, the long period of time when the ankle needs to be kept still leads to its own problems. In extreme cases, this can result in clots in the leg (DVT).
Treatment
Treatment varies depending on the severity of the rupture.
Partial tears
These can often be treated with a plaster or fibreglass cast. This immobilises the ankle, preventing further injury, while the tendon is able to heal. Typically, the surgeons will put you in an equinus cast (where your foot is plastered so that your toes point down like a ballerina) for a few weeks, then change it to a neutral position cast. The first cast takes the strain off the tendon, allowing it to heal, while the second cast stretches it out, preventing scarring contraction (ie shortening) of the muscle and tendon. Once you are ready, the surgeons will remove the cast and you can gradually move into strengthening and flexibility exercises, then weight-bearing exercises.
Partial tears treated with a cast do have a tendency to re-rupture in comparison to surgical treatment. Despite this, cast immobilisation usually provides excellent return to function for most patients, many of whom are off crutches after 8 weeks.
Full-thickness rupture
When the tear splits through entire thickness of the cord, separating it into two pieces, the surgeon needs to sew the ends of the tendon together again.
For more information on surgical repair, see Surgery for Achilles Tendon Rupture.
Seeking Advice
Your Family Doctor (GP)
Your Family Doctor will be able to diagnose and help treat your problem. He or she will be able to
- tell you about your problem
- advise you of the best treatment methods
- prescribe you medications
- and if necessary, refer you to Specialists (Consultants) for further treatment
When to see your doctor
Seek medical advice immediately if you feel a pop or snap in your heel, especially if you can’t walk properly afterward. An Achilles tendon rupture requires prompt treatment.
Because an Achilles tendon rupture often can impair a person’s ability to walk, it’s common to seek immediate treatment at a hospital’s emergency department.
Preparing for your appointment
You may want to write a list that includes:
- Detailed descriptions of the symptoms and the precipitating event
- Information about past medical problems
- All the medications and dietary supplements you take
- Any questions you want to ask the doctor
Prevention
To help prevent an Achilles tendon injury, gently stretch your Achilles tendon and calf muscles before taking part in physical activities. Perform stretching exercises slowly, stretching to the point at which you feel a noticeable pull, but not pain. Don’t bounce during a stretch. To help the muscle and tendon absorb more force and avoid injury, try exercises that strengthen your calves.
To further reduce your chance of developing Achilles tendon problems, follow these tips:
- Avoid activities that place excessive stress on your Achilles tendons, such as hill-running and jumping activities.
- If you notice pain during exercise, rest.
- If one exercise or activity causes you persistent pain, try another.
- Alternate high-impact sports, such as running, with low-impact sports, such as walking, biking or swimming.
- Maintain a healthy weight.
- Wear well-fitting athletic shoes with proper cushioning in the heels.
Frequently asked questions
Will I need Physiotherapy?
Yes. Physio will help rebuild the strength and flexibility in your ankle. It is especially important to complete a full physiotherapy program if you wish to return to sports.
Length and intensity of physio will vary depending on you, the severity of your injury, and whether or not you have surgery or use a cast.
When can I return to sports?
It is best to consult your surgeon and physiotherapist as timing will vary depending on the injury.
However, many people are able to begin light jogging at around 3 months and sports at around 6 months. Usually these will apply to both surgical and non-surgical treatment.
When can I return to driving?
You must be free of pain and able to perform an emergency stop. This will also depend on which foot was operated on (right or left). If you have had left sided surgery and drive an automatic car you may be able to drive 2-4 weeks following surgery.
What should I do if I have a problem?
If you experience severe pain, excessive swelling, inflammation or discharge please report it to your GP.
If you cannot contact your GP you should contact A&E.