There are many different things that can lead to pain in your ankle joint. One lesser-known cause of this pain is os trigonum syndrome. Here some things you need to know about os trigonum syndrome.

What causes os trigonum syndrome?

The os trigonum is an accessory bone in the foot. Accessory bones are extra, unnecessary bones that some people have and some people don't. The os trigonum sndrowm is quite common as accessory bones go; experts report that as many as half of all people have this extra bone.

The os trigonum forms in some people when the bones in the back portion of the ankle do not fuse together normally. This results in an extra bone. Generally, this extra bone is asymptomatic, and you can go your entire life without knowing that you have an extra bone in your ankle. The only time that this extra bone is a problem is when the bony fragment gets in the way of the motion of your ankle joint.

Your os trigonum may become a problem following a sports injury, such as a fractured or sprained ankle. The condition that results from this is known as os trigonum syndrome.

What are the symptoms of os trigonum syndrome?

The main symptoms of os trigonum syndrome are pain and swelling in the back and outer side of your ankle. This may affect one or both ankles. The symptoms associated with this condition tend to get worse during activity and better with rest. If you notice these symptoms following an ankle injury, make sure to see your podiatrist.

Is this condition serious?

Os trigonum syndrome is a problem because of the effect it can have on your quality of life. This condition can make it hard for you to continue playing sports you love, and worse, it can make daily activities like walking or standing painful. For these reasons, the condition needs to be treated as soon as possible.

How is os trigonum syndrome treated?

Your podiatrist will first try to treat your pain with conservative therapies. These therapies may include things like taping or casting your ankle to keep it immobilized while it heals. Resting is important, so you will be told to avoid activities that could aggravate your injury, like running or other sports. If walking or standing are painful, you may be told to use crutches.

Medications can also be used to ease your symptoms. Your podiatrist may inject steroids into the area around the bone to help reduce inflammation. You may also be told to use over-the-counter painkillers, and if necessary, your podiatrist may prescribe a stronger painkiller.

If these conservative therapies are not enough, surgery will be required to remove your os trigonum. This surgery will be performed under either general anesthesia or spinal anesthesia, depending on your preference. To perform the surgery, your podiatrist will make an incision in the back of your ankle and will carefully remove your os trigonum. This procedure is risky as there are a lot of important nerves and tendons in this area, so podiatrists only perform the procedure when it is absolutely necessary. However, the benefit of this procedure is that it deals with the cause of the symptoms, not just the symptoms themselves.

Once your symptoms are gone, your podiatrist may recommend physical therapy. You will see a physiotherapist, who will lead you through exercises to strengthen your ankle and increase the range of motion of the joint.

If your ankle is sore or swollen, and you have sprained or fractured it in the past, you may have os trigonum syndrome. Make an appointment with a podiatrist right away for an examination.