Sometime, a podiatrist may prescribe a computed tomography (CT) examination (also known as a "CAT scan") to help diagnose and treat a foot or ankle problem. A CT is a kind of X-ray device that takes cross sectional images of a part of the body, giving the physician a three-dimensional image:
Common foot problems a CT exam can address include: arthritis, deformities, flat feet, foreign bodies, fractures, infection, and tumors.
CT scans are often superior to conventional X-rays because they can more accurately pinpoint a suspected problem.
Pregnant women, especially those in their first trimester, are advised against having a CT exam or any X-ray examination.
X-rays of the hand, wrist, arm, foot, ankle, knee, or leg help determine whether a bone has been fractured or injured or damaged by conditions such as an infection, arthritis, or other disease.
Other reasons for conventional X-rays on your feet include:
- Evaluate changes in the bones caused by such things as an infection, arthritis, or other bone disease.
- Help evaluate whether a child's bones are growing normally.
- Locate foreign objects (such as pieces of glass or metal) in a wound.
- To determine whether bones are properly set after treating a fracture and placing a cast on an arm or leg.
Pregnant women, especially those in their first trimester, are advised against having a CT exam or any X-ray examination. Extremity X-rays usually takes only five to 10 minutes.
While extremity X-rays do a good job showing bone fractures or dislocations, they are not very accurate when it comes to showing affected cartilage, tendons, or ligaments. A MRI or CT scan may be prescribed.
MRI (Magnetic Resonance Imaging)
Magnetic resonance imaging is a sophisticated diagnostic procedure to diagnose the following kinds of problems or conditions:
- Injuries of the tendons, ligaments, or cartilage.
MRIs use no radiation like conventional X-rays or CT scans. They employ a large magnet and radio waves to produce a kind of three-dimensional image. MRIs are very good at portraying soft tissues and bones in your feet and ankles.
People with the following conditions may not be good candidates for a MRI:
- A condition that requires a heart pacemaker.
- Electronic inner ear implants.
- Electronic stimulators.
- Implanted pumps.
- Metal fragments in your eyes.
- Some artificial heart valves.
- Surgical clips in your head (particularly aneurysm clips).
If you have a dental filling or bridge, a replacement hip or knee, or tubal ligation clips, you are usually safe to have a MRI.
In most cases, a full exam of the foot and ankle last between one hour to 90 minutes.
Ultrasound is a very effective tool for treating and diagnosing a wide variety of foot and ankle problems. This is especially true for soft tissue problems.
Common problems for which ultrasound may be prescribed include:
- Heel spurs or plantar fasciitis.
- Injuries of the ligaments, tendons, or cartilage.
- Morton's neuroma.
- Presence of foreign bodies.
- Soft tissue masses.
- Tarsal tunnel syndrome.
- Tendonitis or tears in a tendon.
Ultrasound uses sound waves on the body in a way much like radar uses sound waves. The waves hit a targeted area and are bounced back to a recording device, which produces an image based on a set of transmitted waves.
Ultrasound is a completely safe and painless diagnostic procedure.