To review the sesamoid and accessory bones in foot and ankle which are most commonly involved in pain syndromes and to describe the imaging characteristics of those entities.
Sesamoid and accessory bones are small,
nodular or ovoid,
well-corticated bony structures,
being located close to a bone or a joint. Accessory bones derive from unfused ossification centers or from previous trauma.
The most frequently encountered accessory bones in foot and ankle are os trigonum and accessory navicular bone. Sesamoid bones are partially or totally embedded in tendons,
being a part of the gliding mechanism and thus protecting them from injury by reducing friction.
Findings and procedure details
accessory and sesamoid bones are incidental findings on radiographic examinations.
Superior modalities as magnetic resonance imaging,
ultrasound and even scintigraphy can be helpful in difficult diagnostic cases or when associate pathology is suspected. Magnetic resonance imaging is of a great importance in early depiction of bone and joint abnormalities and soft-tissues changes. Os trigonum is formed by failure of fusion of a secondary ossification center at the...
Not so rare,
accessory and sesamoid bones in ankle and foot can be the explanation for a patient’s symptoms.
It is important to be aware of it and to be able to recognize those entities on the imaging in order to set a correct diagnosis.
Soft-tissue an osseous impingement syndromes of the ankle: role of imaging in diagnosis and management.
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Sesamoids and accessory ossicles of the foot: anatomical variability and related pathology.
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