Diagnostic Exams

If you are experiencing foot or ankle pain and your podiatrist cannot determine the cause through a physical examination, you may need a computerized axial tomography scan or CAT scan. (This test is also called a computer tomography or CT scan.)

NEED FOR CAT SCANS

Some conditions that a CAT scan may diagnose include:

• Arch deformities.
• Arthritis, both degenerative and rheumatoid.
• Bone tumors.
• Cysts.
• Flat feet.
• Other foot and bone deformities.
• Foreign bodies.
• Fractures, including stress fractures.
• Infection.
• Osteonecrosis (bone death).

OVERVIEW OF CAT SCANS

A CAT scan uses x-ray technology, but is often considered more advanced than a conventional x-ray since it can create a three-dimensional picture that allows your doctor to more accurately assess the problem.

During a CAT scan, your foot will pass through a doughnut-shaped x-ray machine. This machine will rotate and take internal pictures of your foot and/or ankle. Using computer technology, the machine combines numerous x-ray images to generate cross-sectional views and three-dimensional images of the inside of your foot and ankle.

The detail of these images will give your doctor a clear picture of your foot. This clarity will help your doctor better diagnose your problem. For example, an image from a CAT scan will show a difference between a simple cyst and a solid tumor.

CAT Scan Restrictions

The amount of radiation that you are exposed to during a CAT scan is minimal, so typically there are no restrictions for having this exam. However, if you are pregnant, especially in your first trimester, it is not recommended that you undergo a CAT scan due to potential adverse effects on the fetus.

Although symptoms may not appear as dramatic as those from a fracture or other trauma, diseases and disorders can have an adverse effect on your feet, ankles, and lower legs. Some conditions are specific to your feet or lower legs, where other diseases, like diabetes, do not relate to your feet but can create feet and leg problems (i.e. diabetic neuropathy).

Screenings for these diseases and disorders can assist in determining proper treatment.

IMPORTANCE OF DISEASE SCREENINGS

The sooner you are diagnosed with a disease or foot disorder, the more effective your treatment can be. Also, if caught early enough, you can reduce the severity of some complications that affect your feet and legs.

If you develop symptoms of any type of disease or foot disorder, you should be tested. You can be screened for various diseases, including arthritis and peripheral arterial disease, at your doctor’s office.

DISEASES AND DISORDERS AFFECTING YOUR FEET, ANKLES, AND LOWER LEGS

There are many diseases and disorders that can affect your feet. Some disorders are specific to the foot, ankle, or lower leg while others are diseases that can affect your entire body, and also can cause foot-related issues. Some diseases and disorders than can have an impact on your foot health include:

• Arthritis.
• Cancer.
• Diabetes.
• Fibromyalgia.
• Freiberg’s Disease.
• Gout.
• Kaposi’s Sarcoma.
• Kohler’s Disease.
• Maffucci’s Syndrome.
• Ollier’s Disease.
• Peripheral Arterial Disease.
• Raynaud’s Disease.
• Seiver’s Disease.
• Sever’s Disease.

OVERVIEW OF DISEASE SCREENINGS

Not all diseases and disorders have specific medical screenings. For example, Freiberg’s disease is often discovered after an x-ray is taken for another foot ailment.

However, there are numerous disease screening processes, including:

• Ankle-brachial index (ABI): A simple test that can be performed in your doctor’s office, ABI is a reliable way to diagnose peripheral artery disease (PAD).
• Rheumatoid arthritis screening:Rheumatoid arthritis (RA) is often diagnosed through a series of checks, including:
  • Your medical history.
  • Lab tests.
  • X-rays.
  • Physical examination.
  • Ruling out other possible conditions (i.e. Lyme disease, osteoarthritis, and viruses).
• Diabetes tests: Various laboratory tests, including fasting plasma glucose (FPG) tests, tests for blood levels of glycated hemoglobin, and insulin resistance tests, can be used to diagnose diabetes. Because diabetic neuropathy can affect the nerve functioning in feet, it is important to tell your podiatrist if you are diabetic.
• Gout screening: Blood tests and lab tests to analyze joint fluid can help diagnose gout.
• Fibromyalgia testing: Fibromyalgia can be confused with other illnesses including rheumatoid arthritis, lupus, chronic fatigue syndrome, and Lyme disease, so these and other disorders need to be ruled out. Imaging tests and nerve and muscle studies may help with this diagnosis.

Other diseases and disorders can be found through physical examinations when symptoms manifest themselves.

If you are concerned that you may be affected by one of these disorders, or if you are suffering from pain and discomfort in your feet, ankles, or lower legs, visit your doctor for a medical screening.

Pain and discomfort in your feet and lower legs can hinder your ability to perform simple daily activities like walking, standing, and even sleeping. Through a series of tests and assessments, a podiatrist can determine the cause of the pain and recommend treatment.

NEED FOR PHYSICAL EXAMS

Persistent pain and discomfort in your feet, ankle, or lower legs is not a normal occurrence. It is important to undergo a physical examination not only to determine the underlying cause of the pain and discomfort, but also to find suitable treatment. Because some conditions can worsen if not properly treated, it is important to have a podiatric examination when you notice pain, discomfort, and other symptoms of foot and ankle disorders.

OVERVIEW OF PODIATRIC PHYSICAL EXAM

During a routine podiatric physical examination, your doctor will complete various checks of your feet and ankles. A basic routine will most likely include:

• Hands-on examination – Doctor will feel feet for abnormalities and tender areas.
• Movement assessment – Mobility of the feet and ankle will be checked.
• Muscle appraisal – Through various tests, doctor will check for muscle strength.
• Other tests – If the doctor suspects a particular condition, additional condition-specific tests may be performed.
• Stability evaluation – The stability of the ankle will be tested.
• Visual inspection of:
  • Shoes for abnormal wear patterns.
  • Walking gait to check for abnormal step patterns.
  • Overall foot shape to look for deformity or other abnormality.
  • Skin condition.
  • Health of toe nails.
  • Limb alignment.

If you are suffering from continual pain or discomfort in your ankles, feet, or lower legs, schedule an appointment for a podiatric examination as soon as possible.

Physical examinations and X-rays are great diagnostic tools, but in some cases, magnetic resonance imaging (MRI) is needed to better diagnose pain, discomfort, or swelling in your feet, ankles, and lower legs. Unlike conventional X-rays or CAT scans, MRI scans do not use radiation, which makes this a valuable tool for patients who cannot undergo radiation-related tests. Also, MRIs are better at detecting soft-tissue conditions than X-rays.

NEED FOR MRI DIAGNOSTIC TESTING

In a podiatric setting, MRIs are often used as a non-invasive tool to better examine the internal workings of feet and ankles. Your doctor may use magnetic resonance imaging to diagnose:

• Arthritis and other joint damage.
• Bone injury, including fractures.
• Cartilage damage.
• Infection.
• Ligament injury, including sprains and tears.
• Soft tissue tumors.
• Tendon damage, including Achilles tendon tear.

OVERVIEW OF MRIS

Instead of using radiation like X-rays, MRI exams utilize a combination of a magnetic field and radio waves to produce images of the soft tissue and bones in your feet and ankles.

During an MRI scan, your foot (or whichever body part is being examined) is placed inside an MRI machine, which has a strong magnet. Similar to an X-ray, you should not experience any unusual sensations during the scan. After the scan, your doctor will be able to review the images and discuss any findings with you.

MRI RESTRICTIONS

Because MRI scans use a magnetic field to create images, there are some limitations to who can undergo these scans. You may not be a good candidate for an MRI if you have any of the following conditions:

• Artificial heart valves.
• Artificial limbs or metal prostheses.
• Brain aneurysms clips.
• Cardiac pacemaker or defibrillator.
• Electronic inner ear (cochlear) implants for hearing impairment.
• Implanted medical devices with metal, including IUDs.
• Implanted nerve stimulators (TENS implants).
• Implanted pump for insulin or narcotics.

Although some of the above conditions may not hinder you from having an MRI scan, be sure your doctor is aware of the condition before undergoing the scan.

Physical podiatric examinations and x-rays can help determine the cause of problems with feet, ankles, and lower legs. Sometimes however, these tools cannot give a clear glimpse of the issues. When these initial diagnostic tools cannot diagnose the condition, an ultrasound is used to help a doctor evaluate pain, swelling, infection, and other symptoms.

WHY AN ULTRASOUND MAY BE NEEDED

An ultrasound can be very helpful in diagnosing various conditions. Many soft-tissue problems and bone injuries can be seen more clearly using an ultrasound instead of a conventional X-ray system. Some of the many conditions that can be discovered using an ultrasound include:

• Bursitis.
• Cartilage injury.
• Foreign bodies.
• Heel spurs.
• Ligament/tendon tears and ruptures.
• Muscle sprains and strains.
• Neuroma.
• Plantar fasciitis.
• Rheumatoid arthritis.
• Soft tissue masses and certain tumors.
• Stress fracture.
• Tarsal Tunnel Syndrome.
• Tendonitis.

In some cases, ultrasounds may also be used as a treatment for the relief of:

• Bursitis.
• Sprains.
• Tendonitis.

ULTRASOUND OVERVIEW

Ultrasounds work by using the same principles involved in sonar. The ultrasound sends sound waves and records the echoing waves while a computer turns the waves into a real-time picture.

The steps of an ultrasound procedure include:

• Applying a water-based gel to the foot, ankle, or lower leg (whichever body part is being examined).
• Pressing a sensor (called a transducer) against the skin – angling and sweeping the sensor to get best view of area.
• Reviewing findings.

In many cases, the ultrasound can be completed in about 30 minutes to an hour.

An X-ray uses beams of low-level radiation to create a picture of the inside of your body. Bones and other dense materials (including foreign objects) reflect the rays differently and appear white on the X-ray picture. The produced image allows the doctor to see any breaks, growths, or abnormalities.

Although the amount of radiation from a single X-ray scan is not considered harmful to adults, pregnant women should avoid X-rays when possible and should use a lead apron to shield the fetus when necessary.