Reducing the risk of a blood clot for patients with a leg injury needing immobilisation

When you have your leg held in a fixed position by a cast or appliance you are at a higher risk of developing a blood clot.

This leaflet will explain the treatment you may have to prevent a blood clot developing, if you are unable to weight bear following a leg injury. Weight bear means putting weight on your injured leg.

How does a blood clot form?

There are many veins in the calf muscles of each of your legs. As you walk, run or move your feet, the muscles squeeze the veins and blood moves towards your heart. This is known as the calf muscle pump.

If you hold your leg in one position (immobilised) in a cast or appliance, the calf muscle pump does not work as well. This can lead to blood collecting in your veins, which can lead to a blood clot forming. This type of blood clot is known as venous thromboembolism or VTE.

Is a blood clot life threatening?

A blood clot itself may not be life threatening. However, if a part of it comes loose and travels to your lungs it becomes a pulmonary embolism (PE). A PE is a serious condition which can be fatal if not treated.

Am I at risk of a blood clot?

Having your leg immobilised in a cast or appliance can increase your risk of blood clots. However, some people are more likely to develop a blood clot than others. You are at increased risk if you:

• have a personal or family history of blood clots

• have cancer or you are having cancer treatment

• are taking the combined oral contraceptive pill or hormone replacement therapy (HRT)

• are overweight (body mass index (BMI) of 30 or more)

• are pregnant or have had a baby within 6 weeks

• have a disorder which makes your blood more likely to clot

• have recently had an operation.

How can the risk be reduced?

A doctor or nurse will complete a simple assessment to work out your personal risk. If you need treatment, you will be offered anticoagulant medication to help slow down clot formation. You will be given the medication either as a daily injection or tablet.

You must take anticoagulants for the whole time you have the cast or appliance on your leg or are non-weight bearing.

Fracture Clinic staff can show you how to give yourself the injections. If you have any problems, other arrangements will be made with your GP.

Whilst you are being treated you may also need routine blood tests. The doctor or nurse assessing you will tell you when and if you will need these. They may give you blood forms for you to make an appointment at your GP surgery.

Whether you need anticoagulants or not, you should follow the advice below.

• Move around as much as possible (unless your doctor or nurse have told you otherwise).

• Drink plenty of fluids to avoid dehydration (this does not include alcohol).

• Regularly take painkillers, as needed.

Are there side effects to taking anticoagulants?

As with all medicines, anticoagulants can have side effects. Common side effects include increased bleeding and bruising easily. If you notice significant bleeding or bruising, contact your GP immediately. If the bleeding does not stop after a few minutes, call 111.

For more information on possible side effects, please speak to your doctor.

What are the signs and symptoms of a blood clot?

If you have any of the following symptoms, contact your GP or call 111 immediately.

• Pain or swelling in your legs.

• Change in colour of the skin on your legs (red, purple, blue) or feels hot.

• Shortness of breath.

• Pain in your chest, back, or ribs which is worse when you take a deep breath.

• Coughing up blood.

What should I do if I develop signs or symptoms of a blood clot?

Contact your GP or 111 immediately. If you have severe shortness of breath or chest pain, dial 999 for an ambulance.

Useful contact numbers

• Fracture Clinics

  • Kent and Canterbury Hospital, Canterbury
    Telephone: 01227 866354

  • Queen Elizabeth the Queen Mother (QEQM) Hospital, Margate
    Telephone: 01843 235056

  • William Harvey Hospital, Ashford
    Telephone: 01233 616849

• DVT (deep vein thrombosis) Clinics

  • Kent and Canterbury Hospital, Canterbury
    Telephone: 01227 864246

  • Queen Elizabeth the Queen Mother (QEQM) Hospital, Margate
    Telephone: 01843 234525

  • William Harvey Hospital, Ashford
    Telephone: 01233 651841