Items tagged “ossicle”
28 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 millimetres 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 centres 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...
Case
Ossicles of the wrist and hand
Published
28 Jul 2013
16% complete
Annotated image
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...
Case
Os radiostyloideum and triquetral fracture
Published
02 Oct 2013
86% complete
X-ray
Annotated image
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...
Case
Lateral malleolus avulsion fracture with os subfibulare
Published
09 Dec 2013
86% complete
X-ray
Annotated image
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 centre of the metatarsal...
Case
Os triangulare
Published
20 Feb 2014
85% complete
X-ray
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...
Case
Medial malleolus ossicle
Published
26 Feb 2014
66% complete
X-ray
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