Learning objectives
To learn how accessory ossicles can become symptomatic and what are their spectrum of appearances and clinical manifestations.
Background
Accessory ossicles are generally regarded as clinically insignificant anatomic variations,
when in fact they can become symptomatic.
They can suffer traumatic events (e.g.
acute fractures,
stress fractures,
pseudarthrosis).
Neoplastic and osteoarthritic disorders are also reported,
as well as inflammatory and degenerative conditions.
Findings and procedure details
This presentation reviews thereported symptomatic accessory ossicles and suggests guidelines on their imaging diagnosis while attempting to provide some clinical-radiological correlation.
We provide our own examples of the more commonly symptomatic ossicles:
1.
os odontoideum;
2.
Accessory Navicular;
3.
os acromiale;
4.
os subfibulare;
5.
os trigonum;
6. Carpal Boss;
7.
os calcaneus secundarius;
8.
os peroneum;
9.
os intermetatarseum.
1.
OsOdontoideum
Location
Unfused dens axis fragment,
adjacent to C2 vertebral body.
General Incidence
Symptoms
Atlantoaxial instability (anterior or posterior atlantoaxial subluxation) iscommon.
May lead...
Conclusion
Normal anatomic variations are frequently overlooked as a minor finding,
sometimes not being reported when identified,
when in fact they can be the source of a patient's symptomatology.
Learning the key imaging characteristics of these pathologies is essential for determining whether or not to attribute clinical symptoms to the accessory ossicles.
Personal information
J.
Saraiva1
C.
Bilreiro1
L.
Silva1
C.
Carneiro1
B.M.Q.
Santos1
M.O.E.
Castro1
All authors declare to have no conflits of interest on this publication.
1Serviço de Radiologia,
Centro Hospitalar do Algarve,
Unidade Hospitalar de Portimão,
Sítio do Poço Seco,
8500 Portimão - PORTUGAL
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