In most cases, your doctor can tell that you have a foot ulcer simply by looking at your foot.
If you have diabetes, your doctor will assess your control of your blood sugar. He or she will ask about the care that you take to keep your feet healthy. The doctor will ask about the type of shoes that you usually wear.
Your doctor will evaluate the ulcer to determine:
How deep the ulcer is
Whether there is an infection
Whether that infection has developed into cellulitis (a deep skin infection) or osteomyelitis (an infection of the bone near the ulcer)
Whether you have any foot abnormalities, circulatory problems or neuropathy that will interfere with healing.
Your doctor may ask you to walk as part of your examination. This is because your gait may highlight knee and ankle abnormalities that cause abnormal pressure spots on the feet. Your doctor also will look for other foot problems, such as claw foot or fallen arches.
To check for neuropathy, your doctor may:
Test the sensation in your feet
Check your reflexes
Use a tuning fork to see if you can feel the vibration in your toes
Your doctor also can test the circulation in your legs and feet. He or she can do this by feeling your pulses and noting whether your feet are pink and warm. If your pulses are weakened, then your doctor may use Doppler ultrasound to test your circulation.
Your doctor may use a cotton swab or other thin probe to examine the ulcer itself. These tools can be used to see how deep the ulcer is. And they can help check for exposed tendons or bones. Your doctor will look closely for redness around the ulcer. A large margin of redness can be a sign of cellulitis.
Your doctor may order other tests to better understand the extent of the ulcer and to determine whether it is infected. These tests may include:
Bacterial cultures of the ulcer
Magnetic resonance imaging (MRI)
A computed tomography (CT) scan
A bone scan