Patient Education

Tarsal Coalition

Description

It sounds like a great thriller novel, doesn’t it? A Coalition of Bones. You might imagine a story about a terrible secret enclave of powerful people (or perhaps powerful skeletons), or maybe a horrifying and mysterious murder that can only be solved by the unusually wise bakery owner, or the little old lady with all the cats and an eye for clues.

But, the truth is that a coalition of your bones has nothing to do with murders or secret societies. (Usually.) Instead, it refers to bone material, cartilage, or fibrous tissue that grows in between two bones of a joint, effectively immobilizing it. Or, sometimes there’s a bar of bony tissue connecting two bones that don’t normally touch or have a joint between them. In the case of a tarsal coalition, the growth takes place between the tarsal bones (the calcaneus, talus, navicular, cuneiform, and cuboid bones) that form the back of the foot.

This unusual connection between your bones doesn’t generally happen because a dark conspiracy orders it. Instead, it may happen while you’re still a fetus. If this is the case, the joints between your bones, as well as the cartilage lining the joint, never really fully develops. But, you probably won’t develop symptoms until the bones of the foot start to actually mature (around ages 9 to 16), or you may be symptom-free into adulthood, or even never develop symptoms. Tarsal coalitions can run in families (kind of like the mafia), or they can develop as a result of previous injury in the area, abnormal bone growth, infection or arthritis. You can have a tarsal coalition in one foot, or both.

Symptoms

Because tarsal coalitions prevent you from moving one of the joints in your foot, the other joints will be under more stress as you try to do normal things like walking, standing, and chasing down murder suspects. Your other joints will try to compensate for the motionless one, but they’ll likely become inflamed as they’re under more stress than usual.

Typical symptoms of a tarsal coalition usually appear when you’re a teenager or younger adult, and may include a deep ache around the ankle or the back of the foot. The muscles on the outside of your leg might also spasm and cramp as they attempt to move bones that refuse to be budged. Your legs might feel tired, and your ankle and foot might feel rather stiff. Also, if you have a tarsal coalition, you might notice that your affected foot (or feet) seems rather flat, and doesn’t seem as flexible as your other foot (if you have the coalition only in one foot) or your friends’ feet (if you have a coalition in both feet).

Diagnosis

While your podiatrist may or may not own a bakery shop or have a plethora of cats at home (or in his or her office), he or she is excellent at finding clues related to foot problems. While a tarsal coalition may be difficult to diagnose while you’re still young, it becomes easier to find as you (and your bones) mature.

In order to diagnose the condition, your podiatrist will ask for a history of your symptoms, including how long they’ve been going on, how the symptoms have developed over time, etc. Your foot doctor will need to do a physical examination of your foot, and will also likely want to order some X-rays to make a firm diagnosis. If, for some reason, the coalition isn’t obvious on an X-ray, other imaging studies such as a CT scan may prove helpful.

Treatment

There are a few things that can be done to conservatively treat a tarsal coalition. These involve supporting and resting the foot so that your pain, muscle spasms and inflammation can improve. Your podiatrist may recommend one or several of the following treatments:

  • Immobilization – This can be done by putting your foot in a cast or cast boot. You might need to hobble around on crutches for awhile, but that can actually be pretty enjoyable (although it may make sleuthing a bit awkward).
  • Orthotics – These prescription shoe inserts are designed specifically for your feet, and can help compensate for your tarsal coalition, which means that the other joints in your foot won’t have to work so hard to keep your feet moving, and thus won’t hurt as much.
  • Medication – Your podiatrist may suggest oral anti-inflammatory medication such as ibuprofen, or may recommend a cortisone shot to reduce painful inflammation in your foot. Some people may need more than one cortisone shot.
  • Physical therapy – Physical therapy may be used to help improve your range of motion, to massage your stressed and cramping muscles, or your doctor may have you undergo ultrasound therapy.
  • Surgery – If other methods fail to adequately improve your symptoms, your podiatrist may recommend surgery. Also, surgery is really the only treatment that will actually improve or get rid of the original coalition itself. Your surgeon will likely want to remove the coalition between your bones and improve your range of motion. If you have significant deformities from the coalition (such as a severely flat foot), you may need additional surgery to correct these problems as well.