Bipartite Sesamoids

By Giulia Maruzza|2024-12-19T22:56:41+00:00July 17th, 2024|

What are Bipartite Sesamoids?

Sesamoid bones in the foot are two small circle-shaped bones that are embedded in tendons and provide support and leverage for the foot. They can be found under the first metatarsal head (under the big toe joint) and are called the medial (tibial) and lateral (fibular) sesamoids.

Bipartite Sesamoids are a sesamoid bone that are divided/split into two parts – typically, due to an incomplete union during development. The medial sesamoid bone is commonly found to be bipartite. They are considered a common anatomical variant. With the bones split appearance, it is important to differentiate if the sesamoid bone is a bipartite sesamoid (smooth edge) or fractured (jagged edge).

Due to its characteristics, it is common that the split sesamoid bone is more likely to be prone to sesamoiditis (inflammation of the sesamoid bones), which can cause immense pain at the bottom of the big toe joint.

The cause of sesamoiditis in bipartite sesamoids

Due to the split sesamoid bone, it often is associated with experiencing increased repetitive trauma and or stress. Predisposing elements such as the female sex, high BMI (body mass index), foot / gait abnormalities, footwear (with increased forefoot pressure), and certain athletic activities (running / jumping) increase the risk of sesamoiditis in bipartite sesamoids.

Sesamoiditis can have either a chronic or acute effect on the foot. Chronic sesamoiditis can be commonly related to repetitive exercise or continued use of inappropriate footwear. Further studies have also found that those with bipartite sesamoids have an increased risk of developing bunions.

Signs and symptoms of sesamoiditis in bipartite sesamoids

Signs and symptoms of bipartite sesamoids can include:

Pain: Commonly found on the ball of the foot, either dull and aching or sharp and stabbing.
Stiffness and reduced mobility: Limited range of motion and difficulty to flex the big toe.
Swelling: Contributing to stiffness in the area and further tenderness.
Difficulty performing weight-bearing activities: (walking / running) due to all the above.

Treatment options for sesamoiditis in bipartite sesamoids

Treatment options for symptomatic bipartite sesamoids include:

Pain management: To assist in alleviating pain and discomfort.
Physical therapy: To improve the strength of surrounding muscles and improve foot biomechanics.
Footwear: Certain shoes to reduce strain on the affected area and improve foot function.
Custom Orthotics: To further reduce strain and redistribute pressure from the affected area.
CAM Walkers: In cases where there is inability to weight-bear, a CAM Walker may be required to settle down pain and assist in offloading.
Cortisone injections: In severe cases of inflammation surrounding the big toe joint, an injection may further reduce inflammation and pain.
Surgery: Commonly found to be a last resort option, after exhausting conservative treatment.

How our Melbourne Podiatrists can help?

Our Melbourne Podiatrists will be able to accurately diagnose the type of big toe joint pain, by physically examining the foot & understanding the patient’s symptoms and medical history. They may also suggest imaging studies (such as x-rays / CT scans / MRI) to be conducted to confirm the diagnosis & further evaluate the affected area of pain.

Our Podiatrists will provide specified treatment options for sesamoiditis in bipartite sesamoids, depending on the severity. This can include footwear, exercises, lifestyle modifications and inserts to manage symptoms and prevent further complications

So if you are experiencing pain associated with sesamoid bones, see one of our Melbourne Podiatrists for accurate diagnosis and treatment.