Ankle Sprain

Diagnosis

Your doctor will ask you questions about your injury and your symptoms. You’ll be also be asked if you have injured your ankle in the past.

Your doctor will examine your ankle to determine the extent of the sprain and to make sure that you haven’t fractured a bone. He or she will touch various points of your ankle and foot, and perform several tests to determine the extent of damage to your ligaments. For one of these tests, known as the anterior drawer test, your doctor will cup the heel of your injured leg in one hand and then gently pull the heel forward while holding firmly with his or her other hand to your lower shin. For another test, known as the taler tilt test, your doctor will carefully rotate your ankle outward. You’ll also be asked to put weight on your injured ankle. If you experience pain when a bony area is touched or when attempting to stand or walk, you may have a fracture.

Children need to be examined especially carefully to make sure that their symptoms are not a result of injury to a pediatric growth plate—which can mimic symptoms of a sprained ankle. The doctor will apply pressure to the growth plate areas; if the child feels pain, the plate may be broken.

Doctors grade sprains according to the severity of the injury.

• Grade I sprain. This mild sprain results in a stretched or slightly torn ligament, but only slight pain or swelling. You can put weight on the joint and move it with no discomfort.
• Grade II sprain. This moderate sprain causes partial tearing of the ligament, resulting in moderate pain and swelling and perhaps some bruising. You will have some difficulty putting weight on or moving the joint.
• Grade III sprain. This severe sprain causes a complete rupture of the ligament. Pain, swelling, and bruising is severe. You can’t put weight on or move the joint.

If your doctor suspects a fracture, he or she may order an x-ray of your ankle. To determine if a ligament has been completely ruptured, your doctor may also order special “stress” x-rays. These are standard x-rays that are taken while someone rotates or stresses the ligaments in the injured joint.

In some cases--high ankle sprains, for example--doctors order computed tomographic (CT) scanning or magnetic resonance imaging (MRI). Both of these tests produce more detailed images than standard x-rays. A CT scan uses a combination of x-rays and computer technology to produce cross-sectional images (often called slices) of the body. MRI uses a combination of large magnets, radio frequencies, and a computer to produce its images.

Prevention and Screening

You can do many things to lower your risk of spraining your ankle.

• Wear shoes that fit properly and that provide plenty of stability
• Avoid wearing high-heeled or platform shoes
• Exercise on even surfaces
• Wear a brace or have your ankle taped when participating in sports with a high incidence of ankle injuries
• Do ankle-strengthening exercises several times a week
• Stretch your leg muscles daily