Sesamoiditis — inflammation of the sesamoid bones of the big toe — is a common cause of big toe pain in runners. It’s important to distinguish it from other problems affecting the big toe, such as big toe arthritis or gout, as well as from a sesamoid stress fracture or a bipartite sesamoid. So how does sesamoid bone pain present, and what are the treatment options?
What are the sesamoid bones?
We have two small sesamoid bones under the big toe — the medial and the lateral sesamoid. A few people are missing one or both. In others, a sesamoid is split into two parts — a bipartite sesamoid. These little bones are essential for pushing off from the big toe when walking or running at speed.
Sesamoid pain can come on suddenly after trauma, or gradually with excess activity.
What causes sesamoiditis?
Sesamoiditis is an overload injury. Repetitive, forceful push-off through the big toe irritates the sesamoids and the tendons around them. Common triggers include:
- Running — especially forefoot strikers — and sports with forceful push-off
- Ballet dancing (en pointe), which compresses the sesamoids maximally
- High arches (a cavus foot), which concentrate load on the forefoot
- Thin-soled or high-heeled shoes, which increase pressure under the big toe
- A sudden increase in training
Symptoms of sesamoiditis
People typically report pain directly under the big toe joint — on the ball of the foot — rather than in the joint itself. Other features include:
- Pain that builds gradually and worsens with push-off, walking, or running
- Tenderness when pressing on the sesamoid
- Swelling under the big toe
- Difficulty bending and straightening the big toe
Sesamoiditis, a bipartite sesamoid, or a stress fracture?
This is the key to getting it right, because the look-alikes are treated differently.
- Sesamoiditis develops gradually as an overload, and the pain is reproduced by pressing on the sesamoid and by bending the big toe upwards.
- A bipartite sesamoid is a normal variant — the medial sesamoid split into two parts — present in roughly 10–25% of people. It’s not a fracture, but a split sesamoid is more prone to becoming painful. On X-ray, it has smooth, rounded edges.
- A sesamoid stress fracture has jagged, irregular edges on X-ray that don’t match the contour of the other side, and is best confirmed on MRI, which shows swelling within the bone.
Because a bipartite sesamoid and a fracture can look similar, imaging and an experienced assessment matter — misreading one for the other leads to the wrong treatment.
How is sesamoiditis diagnosed?
We combine examination with imaging—an X-ray checks for a fracture, a bipartite sesamoid, and big toe arthritis. Ultrasound assesses the surrounding soft tissue, while MRI is the most sensitive test for a stress fracture and for confirming sesamoiditis.
Treatment of sesamoiditis
Most sesamoiditis settles with simple, conservative treatment — the cornerstone is offloading the sesamoid.
- Reduce push-off activities — the single most important step, cutting back running, dancing, and forefoot loading until the pain settles
- Offloading pads and orthotics — a dancer’s pad or a cutout insole — take pressure off the sesamoid.
- Stiff-soled or rocker-soled shoes — reduce the bend and load through the big toe
- Anti-inflammatory measures — ice and ibuprofen for pain and swelling
- A graded return to activity once the pain has settled
Is an injection helpful for sesamoiditis?
We’re cautious here. Injecting the big toe joint means some cortisone bathes the top of the sesamoid, which can help. But we generally avoid injecting directly into the sesamoid bone itself, because of the risk of damaging the surrounding soft tissue in this heavily loaded, thin-tissue area. In some cases, we consider injecting the 1st toe joint – which bathes the undersurface of the sesamoid and avoids risking damage to ligaments and tendons attaching to the sesamoid.
Where an injection is used, we do it under ultrasound guidance to place it accurately and avoid the tendons and other important structures.
Do you need surgery for sesamoiditis?
Rarely — and we advise avoiding it wherever possible. Removing a sesamoid (sesamoidectomy) can upset the mechanics of the big toe and cause new problems, so it’s a last resort for the rare case that fails all other treatment. The great majority of people recover with offloading and patience.
Frequently asked questions about sesamoiditis.
How long does sesamoiditis take to heal?
Recovery is slow. We typically see full recovery within 3–6 months, though it can take longer, and most people take around 3–6 months to return to sport. Sesamoiditis is a frustrating condition precisely because it’s slow — persisting with offloading is what gets you there.
What is a bipartite sesamoid, and is it a problem?
A bipartite sesamoid is a normal variant — the medial sesamoid formed in two parts rather than one — found in roughly 10–25% of people. It’s not a fracture, and often causes no trouble at all. Occasionally it becomes painful, in which case it’s treated much like sesamoiditis. The main pitfall is that it can be mistaken for a fracture on X-ray.
How do I know if it’s sesamoiditis or a fracture?
Sesamoiditis develops gradually with overload; a fracture often follows a specific injury or hyperextension of the big toe. On X-ray, a bipartite sesamoid has smooth edges while a fracture has jagged ones — but the two can look alike, so an MRI is often needed to be sure. Getting this right matters, as the treatment differs.
What are the best shoes for sesamoiditis?
Stiff or rocker-soled shoes that limit big-toe bend, with good cushioning under the ball of the foot. Avoid thin-soled and high-heeled shoes, which increase pressure on the sesamoids. A dancer’s pad or an orthotic that offloads the sesamoid is often the single most helpful addition.
Can I keep running with sesamoiditis?
Not through the pain. Continued push-off loading is exactly what drives the problem, so a period of reduced or modified activity is essential. Once the pain settles, a graded return — guided by symptoms — helps prevent it from coming straight back.
Final word from Sport Doctor London about sesamoiditis
Sesamoiditis is a common but slow-healing cause of big toe pain, especially in runners and dancers. The keys are an accurate diagnosis — distinguishing it from a bipartite sesamoid, a stress fracture, and big toe arthritis — and diligent offloading. We’re cautious about injecting the sesamoid, and we advise avoiding surgery in almost all cases.
If you have persistent pain under your big toe, Dr Masci can assess you in London, including an in-clinic ultrasound. Contact the team here or call +44 (0) 203 488 0350.
Leave A Comment