Gout is a condition that often affects the big toe joint causing redness, heat, swelling and extreme tenderness. A patient with gout will often say that they can’t fit into shoes because the foot hurts so bad. They can’t move the big toe without pain. Even a bed sheet resting on the foot can cause excruciating pain. So what is gout in the foot?
What Causes Gout?
Gout is a form of arthritis (inflammation of the joint). In short, it inflammation caused by the buildup of crystals within the joint. Although gout typically produces pain in the big toe joint, it can occur in other joints such as the ankle, knee and elbow. But it is far more common in the joint at the base of the big toe joint (referred to by doctors as the first metatarsal phalangeal joint).
Although gout usually only causes joint pain, it is actually a metabolic disorder, not just a joint problem. People who get gout are unable to properly process and remove some of the byproducts of the food they eat. As a result, uric acid crystals gradually build up in the blood stream.
Once the concentration of uric acid in the blood gets high enough, sodium urate (uric acid) crystals start to get deposited in areas of slower temperature and decreased blood flow, like the big toe joint.
We can use an analogy to explain how this happens. Take a glass of iced tea. If you put in a couple of spoonfuls of sugar and stir, the sugar crystals will dissolve. If you keep adding sugar, sooner or later the crystals will stop dissolving and settle to the bottom of the glass.
If you now take the glass of tea and heat it, the crystals will dissolve. But as the glass of tea cools, the sugar crystals will start to form and again settle in the bottom of the glass.
This is basically what happens when the blood containing all of the uric acid flows through the big toe joint. The temperature is lower at the end of the foot toward the toes. Crystals start to form in the big toe joint.
Once the uric acid crystals have formed within the big toe joint, inflammation begins. What you see is a warm, red, swollen and very painful joint.
Who Gets Gout?
Gout has been described as the “affliction of Kings” and a “disease of the aristocracy.” It used to be that only those lucky, rich, members of the royal family would get the disease. For a long time (before we understood the biochemistry behind the disease, it was thought that it must be some inherited problem that only affected the royal families.
It turns out that gout has a lot to do with diet. To get gout, you have to have a diet rich in purines. Purines are found naturally in very high concentration in meat, seafood and beer
The reason that kings and queens used to only get is simple. They were the only ones who could afford to eat enough meet and alcohol to develop gout. The average people (the peasant workers) just didn’t eat the same food.
Today the typical North American diet is loaded with purines. In one year each American eats an average of 200 pounds of meat. Now that you can get a hamburger off the dollar menu, it is easier than ever before to fill up on the food that causes attacks of gout.
What Puts You at Risk for Gout?
Once you eat all of that food rich in purines, it is up to your kidneys to filter them out of the blood and excrete them in the urine. Some people have an inherited tendency to accumulate (build up) uric acid. These people are more at risk of having an attack of gout. But many other factor an affect you ability to remove uric acid from the blood. Kidney disease, high blood pressure (hypertension), diabetes, obesity, chemotherapy, stress, surgery and some medications and vitamin supplements can increase your risk of a gouty attack.
How Do I Know if I Have Gout?
You might have gout if you have:
• Pain in the big toe joint or ankle without any specific trauma or injury
• Pain gets worse as with activity (walking, running, or standing)
• You find it hard to participate in some activities
(such as running, climbing, cycling, hiking, rollerblading or skiing)
• Pain in the big toe joint or ankle, even at rest
• You noticed swelling or redness around the big toe joint
• A tender spot at the base of the big toe or near the ankle or midfoot
• Big toe joint hurts much worse with tight shoes
• You had a gradual increase in pain after some activity
• Limping or changes in the way that you walk
What will the Foot Doctor do for Gout in the Big Toe Joint?
Your doctor visit will begin with the doctor taking a complete medical history to make sure he/she has the full story. A physical exam will be performed. X-rays of the foot and toes will also be taken to further evaluate the condition and make sure that there is no risk for other less common, but dangerous conditions (such as a foot fracture, bone infection or bacterial infection that produces gas in the tissues). Although MRI, CT scan, Ultrasound and bone scans can all be performed to get more detail than can be seen on x-ray, it is usually not needed. MRI shows inflammation much better than an X-Ray, but MRI is usually only done if an infection, fracture or dislocated joint is suspected. Sometimes it is necessary to perform blood tests to see if the White Blood Cell count is elevated and determine kidney function before starting treatment.
Can X-Rays show Gout?
Yes and No. In most cases, the X ray is normal during the initial attack of gout. However, if the joint is really packed with crystals, the joint space (that is usually black) will look opaque or grey on xray.
If you have had many gout attacks, there are changes that occur in the joint that only happen with gout. Little erosion (areas where the bone dissolved) in the joint (where the joint capsule attaches to the bone) begin to show up on xray. Some people refer to these areas of missing bone as “rat-bite lesions” because it looks like a rate took a bite out of the edge of the bone. Doctor’s call this Martel’s sign.
Can a Blood Test Diagnose Gout?
Yes and No. If your blood is drawn just before an attack of gout, the uric acid level will be very high. Once the attack of gout begins, all of that uric acid leaves the blood stream and ends up in the joint in the form of crystals.
So many times a doctor will draw some blood and check the uric acid level when the patients is suspected of gout. But the uric acid isn’t in the blood anymore, it is in the joint. So the blood test comes back normal. And the doctor (incorrectly) tells the patient that he or she doesn’t have gout.
If the uric acid level happens to remain high during the attack, a blood test can be used to diagnose gout, but it isn’t very reliable.
Best Way to Diagnose Gout
The most accurate way to diagnose gout is with joint aspiration. The foot doctor draws a small sample of joint fluid out and looks at it under a microscope. During a gouty attack, the synovial fluid is just chock-full of little need-like rhomboid shaped crystals. Then we know for sure that all these tiny sharp needles poking the inside of the joint are causing the pain and inflammation.
Treatment of Gout
The good news about attacks of gout is that once diagnosed, it can be quickly treated. With the correct treatment, the pain will be gone in a few hours to a couple of days.
Most initial treatments for gout target the inflammation in the joint. If joint aspiration was performed, steroids can be injected right into the joint to stop all of the inflammation and pain.
But the mainstay of treatment for gout involves powerful oral anti-inflammatories medications. Colchicine and Indomethacin are the drugs most often prescribed for gout. They are much more effective than Tylenol, ibuprofen and other NSAIDs. Most people will generally get relief from a gouty attack by the time they have taken a few of these pills.
If someone has repeated or recurring attacks of gout, treatment starts with diet modification. A low-purine diet is often all that is needed to prevent gout from happening again.
If after modifying the diet, you still keep having more bouts of gout, other medicines can help. Allopurinal is a medication often prscribed for gout. It blocks an enzyme called xanthin oxidase. Blocking this enzyme decreases the amount or uric acid you body produces and hence, can decrease the chances for gout attacks. But don’t ever atart taking allupruinol during a gout attack, as it might actually backfire and make the attack worse.
When to See a Foot Doctor for Gout
Any time you have pain, swelling and redness in a joint you should consider this a medical emergency. You must seek help right away. Gout is very painful and that alone is reason enough to get help. But even more concerning is that other conditions that look like gout can be dangerous; even life threatening.
Charcot arthropathy is an emergency that can look like gout, but is actually more serious. It is most common in people with diabetes. It is important to start treatment for Charcot right away to prevent further damage and the potential for losing the foot to an amputation.
Soft tissue infections and infection arthritis (where there is bacteria growing within the joint) are both absolute emergencies that can look a lot like gout. Without treatment foot and joint infections can lead to an amputation or even death if sepsis (an infection in the blood stream) develops.
Because gout can look a like some very serious problems, you should immediately see a foot and ankle specialist if you have a red, hot painful, swollen foot or big toe joint. If your doctor’s office says they can’t see you right away, call someone else who will see you the same day. Otherwise, call 911 or head to the emergency room. Whatever you do, don’t wait.
Dr. Christopher Segler was selected in 2010 as one of "America's Top Podiatrists." He has a podiatry house calls practice in the San Francisco Bay Area. If you have gout and need pain relief right away, he makes podiatry emergency house calls 24/7. If you think you might have gout and would like to speak directly with him to ask a question, you can call him (415) 308 0833.