Behind the Neck Pain: What You Need to Know About Cervical Facet Joints
Understanding Sesamoiditis and Sesamoid Bone Pathologies
When we think about common foot injuries, ankle sprains or plantar fasciitis often come to mind. But hidden beneath the big toe lies a small set of bones that can cause surprisingly large problems: the sesamoids.
What Are Sesamoid Bones?
Sesamoid bones are small, round bones embedded within tendons. In the foot, they are found beneath the first metatarsophalangeal (MTP) joint, sitting under the big toe. Although tiny, they are biomechanically important:
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They protect tendons from stress and wear
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Reduce friction and mechanical overload during movement
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Act as shock absorbers, transmitting 50–300% of body weight depending on activity
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Improve leverage and efficiency in walking, running, and jumping
The medial (tibial) sesamoid is more commonly injured because it is larger and carries greater weight-bearing load.
What Is Sesamoiditis?
“Sesamoiditis” is a frequently used clinical term but lacks a universally accepted definition in medical literature. Broadly, it refers to pain and inflammation of the sesamoid bones and surrounding soft tissue, often in the absence of fracture.
It is most commonly seen in athletic and active populations due to repetitive loading. Sports such as running, tennis, basketball, soccer, and dance carry higher risks.
​Causes and Risk Factors
Sesamoiditis and other sesamoid injuries may develop due to:
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Repetitive stress (running, jumping, dancing)
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Acute trauma (sudden dorsiflexion of the big toe)
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Pre-existing conditions (turf toe, hallux rigidus)
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Foot biomechanics (excessive pronation)
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Inappropriate footwear (e.g., high heels, unsupportive shoes)
Interestingly, sesamoid injuries make up around 9% of all ankle-foot injuries, though they are often underdiagnosed.
Symptoms
Typical symptoms of sesamoiditis include:
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Localised pain under the ball of the big toe (beneath the first metatarsal head)
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Pain that worsens with weight-bearing, running, or wearing certain shoes
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Tenderness or swelling around the sesamoid area
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Occasionally, diffuse discomfort spreading across the plantar surface of the hallux
Diagnosis
Clinical examination is the first step, but imaging is often required:
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X-ray can help rule out fractures or deformities
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MRI is the most sensitive for soft tissue changes, but findings don’t always match symptom severity
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Bone scan or CT may be useful in complex or uncertain cases
MRI often shows soft tissue signal changes, intraosseous abnormalities, or chondral/subchondral lesions. However, pain may also be influenced by neuromechanical and inflammatory factors beyond what imaging reveals.
Treatment Options
CT coronal (A) and axial (B) images showing sclerosis of subhallucal sesamoid bone (white arrows).
Conservative Management:
The majority of cases are treated without surgery:
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Activity modification: avoiding running, jumping, or high heels to allow rest
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Orthotics and footwear changes: insoles, padding, or stiff-soled shoes to offload the sesamoid region
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Physical therapy: shockwave therapy or laser therapy may reduce inflammation and stimulate repair
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Medication: anti-inflammatory strategies as prescribed
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Surgical Options:
For persistent, disabling pain unresponsive to conservative measures, partial or total sesamoidectomy may be considered. While surgery can relieve pain and restore function, potential complications include:
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Hallux valgus (bunions)
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Loss of push-off strength
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Altered gait mechanics
Given these risks, surgery is reserved for carefully selected patients, ideally after a multidisciplinary evaluation.
Beyond Sesamoiditis: Rare Sesamoid Pathologies
While sesamoiditis is common, rarer conditions can also affect these bones:
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Osteonecrosis (avascular necrosis) – occurs when blood supply to the sesamoid is disrupted, leading to bone death. This is particularly reported in ballerinas and athletes.
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Fractures – acute or stress fractures may mimic sesamoiditis but often require different management.
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Degeneration or infection – uncommon but possible causes of sesamoid pain.​
The subhallucal interphalangeal sesamoid (an ossicle at the big toe’s interphalangeal joint) can also develop trauma, inflammation, or osteonecrosis. Diagnosis often relies on MRI, which helps differentiate these conditions from sesamoiditis.
References
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Shimozono Y, Yasui Y, Ross AW, Kennedy JG. Conservative Treatment of Sesamoiditis: A Systematic Literature Review with Individual-Level Pooled Data Analysis. Foot Ankle Spec. 2018;11(6):544-550. doi:10.1177/1938640018761170
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Pretterklieber B. The sesamoid bones of the hallux. Anatomical, functional, and clinical considerations. Clin Anat. 1999;12(6):428-433. doi:10.1002/(SICI)1098-2353(1999)12:6<428::AID-CA7>3.0.CO;2-V
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Karasick D, Schweitzer ME. Disorders of the hallux sesamoid complex: MR features. Skeletal Radiol. 1998;27(9):411-418. doi:10.1007/s002560050414
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Khan NA, Lali A, et al. A False Step in a Ballerina: A Rare Case of Osteonecrosis of Subhallucal Sesamoid Bone. Cureus. 2023;15(4):e37563. doi:10.7759/cureus.37563
