Sesamoiditis is inflammation of the sesamoid bones — two small, pea-sized bones embedded in the flexor hallucis brevis tendon under the big toe joint. These bones act as a pulley for the tendon and absorb the significant forces generated during push-off. When overloaded, they become inflamed, causing persistent pain in the ball of the foot near the big toe.

What Causes Sesamoiditis?

Sesamoiditis typically develops from repetitive overloading of the forefoot. Common causes include:

• Dancing and ballet — en pointe positions place extreme load on the sesamoids
• Running, particularly on hard surfaces — forefoot runners and sprinters are especially vulnerable
• High heels — shifts body weight onto the forefoot chronically
• High-arched (cavus) foot — creates a rigid foot that concentrates pressure under the ball of foot
• Sudden increase in activity — starting a new sport or training program without gradual progression

Sesamoiditis Symptoms

The hallmark of sesamoiditis is a gradual onset of pain directly under the big toe joint. Unlike a stress fracture (which causes sudden, sharp pain), sesamoiditis typically develops slowly over days to weeks. Key symptoms include:

• Dull, aching pain under the big toe that worsens with activity
• Swelling and tenderness directly over the sesamoid bones
• Pain with walking barefoot or in thin-soled shoes
• Difficulty bending the big toe downward (flexion)
• Occasional bruising around the big toe joint

Sesamoiditis vs. Sesamoid Fracture: How to Tell the Difference

Both conditions cause very similar pain, but the treatment differs significantly. A sesamoid stress fracture causes more acute, localized pain that intensifies with direct palpation. Sesamoiditis tends to be more diffuse and gradual. An X-ray is usually inconclusive (sesamoids can appear bipartite in 10-30% of normal people); MRI or bone scan provides definitive diagnosis. This distinction is critical — do not simply assume it’s “just inflammation” without imaging.

Treatment Options for Sesamoiditis

Conservative (First-Line) Treatment

• Rest and activity modification — avoiding activities that load the forefoot (4–6 weeks minimum)
• Padding and offloading orthotics — custom orthotics with a sesamoid cutout redistribute pressure away from the painful bones; this is one of the most effective interventions
• Low-heeled, stiff-soled footwear — reduces flexion at the first MTP joint
• Anti-inflammatory medications — oral NSAIDs for acute flares
• Corticosteroid injection — targeted injection into the sesamoid apparatus can provide significant relief when other conservative measures fail

Advanced Treatment

• PRP (Platelet-Rich Plasma) injection — an excellent option for chronic sesamoiditis that has not responded to cortisone; promotes regeneration of the inflamed tendon-bone interface
• Extracorporeal Shockwave Therapy (ESWT) — non-invasive energy delivery promotes healing in chronic cases
• Sesamoidectomy — surgical removal of the affected sesamoid bone is reserved for refractory cases and typically yields excellent outcomes, though recovery is 6–8 weeks

How Long Does Sesamoiditis Take to Heal?

With proper treatment, mild to moderate sesamoiditis typically resolves in 6–8 weeks. Severe cases or those involving a sesamoid stress fracture may require 3–6 months of recovery. The key is accurate diagnosis and strict offloading — athletes who try to “push through” sesamoiditis often progress to a complete stress fracture, significantly extending recovery time.

Dr. Tom Biernacki, DPM

Dr. Tom Biernacki, DPM is a double board-certified podiatrist and foot & ankle surgeon at Balance Foot & Ankle Specialists in Southeast Michigan. With over a decade of clinical experience, he specializes in heel pain, bunions, diabetic foot care, sports injuries, and minimally invasive surgery. Dr. Biernacki is a member of the APMA and ACFAS, and his patient education content on MichiganFootDoctors.com and YouTube has reached over one million views.