Items tagged “ossicle”

17 results found
Article

Os supratalare

An os supratalare is an accessory ossicle of the foot located at the superior aspect of the talar head or neck. Epidemiology It's a rare variant with a reported incidence of ~1% (range 0.2-2.4%) 1. Clinical presentation It is almost always asymptomatic although some cases reported dorsal hin...
Article

Accessory navicular

An accessory navicular is a large accessory ossicle that can be present adjacent to the medial side of the navicular bone. The tibialis posterior tendon often inserts with a broad attachment into the ossicle. Most cases are asymptomatic but in a small proportion, it may cause painful tendinosis ...
Article

Os subfibulare

Os subfibulare is an accessory ossicle that lies at the tip of the lateral malleolus of the ankle and is rarely reported 1. Clinical presentation Os subfibulare are usually asymptomatic although they may eventually cause painful syndromes or degenerative change in response to overuse and traum...
Article

Os subtibiale

An os subtibiale is a rare, genuine accessory ossicle and normal variant related to the posterior colliculus of the medial malleolus 1. It is present in ~1% of the population 5.  Clinical presentation They usually are asymptomatic although they may eventually cause painful syndromes or degener...
Article

Fabella

The fabella (plural fabellae 5) is an accessory ossicle that is almost always found in the lateral head of the gastrocnemius although rarely it can occur in the medial head of gastrocnemius 4. It occurs in ~20% (range 10-30%) of the population 1.  The fabella can also be fibrocartilaginous in n...
Article

Sesamoid

Sesamoids, also known as sesamoid bones, are focal areas of ossification within tendons as they pass over joints 1. They can also occur in ligaments and usually measure a few millimeters in diameter. Their function is purported to be to alter the direction of the tendon and modify pressure, ther...
Article

Accessory ossicles

Accessory ossicles are secondary ossification centers that remain separate from the adjacent bone. They are usually round or ovoid in shape, occur in typical locations and have well-defined smooth cortical margins on all sides. In most cases, they are congenital in origin, although they may occ...
Article

Os supratrochleare dorsale

Os supratrochleare dorsale, also called os supratrochleare posterius is an accessory ossicle of the elbow located in the olecranon fossa of the humerus 1. It may become symptomatic due to trauma during elbow extension and as such may require surgical removal 2. Differential diagnosis osteochon...
Article

Os radiostyloideum

Os radiostyloideum (or persistent radial styloid) is an accessory ossicle of the wrist located adjacent to the radial styloid process and lateral to the mid-portion of the scaphoid.  This should not be confused with another bony ossicle in the wrist, os styloideum (part of a carpal boss), which...
Article

Os supranaviculare

An os supranaviculare is an accessory ossicle of the foot, located at the proximal dorsal aspect of the navicular bone or talonavicular joint. It is also known as Piries bone, talonavicular dorsale, or (dorsal) talonavicular ossicle and is present in ~1% of the population.  Differential diagnos...
Article

Os intermetatarseum

The os intermetatarseum is an uncommon accessory ossicle of the foot occurring in ~4% (range 1-7%) of the population.  Clinical presentation It is usually asymptomatic and an incidental finding although it can be a cause of dorsal midfoot pain.  Gross anatomy The os intermetarseum is typical...
Article

Sesamoid ossicles of the nuchal ligament

Sesamoid ossicles of the nuchal ligament are a relatively common anatomical variant that are usually asymptomatic and most commonly occur at the C5-C6 or C6-C7 vertebral levels.  Epidemiology They occur in ~7.5% of the population, with a male predominance of 3:1 1.  Radiographic features Pla...
Article

Hallux sesamoid

The hallux sesamoid bones are paired ossicles of the foot. They function as a fulcrum to increase the leverage of both flexor hallucis brevis and longus.  Gross anatomy The hallux sesamoids are ovoid-shaped ossicles, separated from each other by the intersesamoidal ridge. There is a medial (ti...
Article

Os vesalianum pedis

An os vesalianum pedis is an accessory ossicle of the foot. Although asymptomatic, it may become symptomatic occasionally, causing lateral foot pain and requiring surgical excision 2. Gross anatomy It is formed as a result of failed fusion of the secondary ossification center of the metatarsal...
Article

Lunula

The lunula is an accessory ossicle of the wrist. It lies in the TFCC, between the tip of the ulna styloid process and the triquetrum. It may be fused to the ulna styloid, giving it an elongated appearance.  Differential diagnosis os triangulare: lies more radial ulna styloid fracture persist...
Article

Os acetabuli

Os acetabuli (plural: ossa acetabuli) are small ossicles adjacent to the acetabular roof regions and may represent an unfused secondary ossification center of the acetabulum or pathological sequelae (e.g. acetabular rim fracture, femoroacetabular impingement). Gross anatomy Ossa acetabuli are ...
Article

Meniscal ossicle

Meniscal ossicles are uncommon, often incidental, findings on radiography and cross-sectional imaging of the knee. Epidemiology Reported to have a prevalence of 0.15% in the general population 2. Clinical presentation maybe an incidental finding may present with intermittent pain joint loc...

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.