The majority of bones in our body are connected to each other at joints, but some bones are not connected to other bones. Instead, they are connected only to tendons or are embedded in our muscles. These bones are known as sesamoids, and the largest one in your body is your patella, or kneecap. You also have two very small sesamoids in your feet. One is located near the forefoot under your big toe, and the other is near the middle of your foot.
Sesamoids have a unique job in that they act like pulleys. They help to provide a smooth surface over which tendons can slide, which allows these tendons to transmit muscle forces. In your foot, your sesamoids help with weight bearing and movement of your big toe. Problems can develop in the sesamoids if the bone itself fractures, or if the tendons surrounding the sesamoid become inflamed or irritated, which is known as sesamoiditis. It’s a common problem among athletes, especially dancers and baseball catchers.
Causes and Symptoms of Sesamoids
Sesamoid fractures and sesamoiditis can be caused by an acute force injury, or degenerative damage over time that leads to inflammation or irritation. Symptoms of the conditions include:
- Pain under your big toe on the ball of your foot, either gradually over time (sesamoiditis) or immediately (acute fracture).
- Swelling.
- Bruising.
- Difficulty bending or straightening the big toe.
Diagnosis and Treatment
Sesamoid fractures and sesamoiditis can be diagnosed with the help of a trained physician. Your foot specialist will ask about your symptoms and look for signs of tenderness and swelling in the sesamoid bones. They may also manipulate your big toe a little to see how the toe reacts and if you experience any discomfort. To confirm their suspicions, your doctor will likely order an X-ray to see if there are any fractures or issues with the sesamoids.
Sesamoids can usually be treated with conservative care methods, but if those methods fail, surgery may be an option. Here’s a look at some of the common non-operative treatment techniques for sesamoiditis.
- Limiting painful activity (a break from sports or running).
- Taking over-the-counter pain relievers or anti-inflammatory medications.
- Rest, Ice, Compression and Elevation.
- Switching to soft-soled shoes, or using a gel insert.
- Slowly returning to activity.
- Anti-inflammatory injections.
Fractures of the sesamoid will be treated a little differently. Treatment options include:
- Wearing a foot fracture brace to protect the sesamoid.
- Using foot pads to prevent extra stress when walking.
- OTC pain relievers.
- Limited activity followed by gradual return to activity.
- Gel or soft custom orthotic shoe inserts.
- Rest, Ice, Compression and Elevation