Learning objectives
Describe post-traumatic cyst-like lesions etiology and present its characteristic imaging features.
Depict how imaging can have a crucial role distinguishing these benign lesions and other pathologic entities,
preventing unnecessary invasive procedures.
Background
Post-traumatic cyst-like lesions are an infrequent complication of fractures in children.
To our knowledge,
no more than 30 cases have been reported.1-4 They most commonly affect the distal radius following a greenstick or torus fracture.1 They are usually asymptomatic,
are not associated with pathologic fractures and typically resolve spontaneously in 1 to 3 years.2 Most are found in the distal radius,
with an age range of 2.5 to 15 years.1
Although etiology is still controversial,
the most accepted theory involves the transcortical leakage of intramedullary...
Imaging findings OR Procedure Details
On plain radiographs,
post-traumatic cyst-like lesions appear as a non-expansile lucent lesion.
They appear proximal to the compression site and are usually identified 2-4 months after a minor fracture.3 This means that,
when formed,
these lesions might be occult unless the patient has a long-term imaging follow-up or is evaluated for pain or re-injury of the same limb.3.
Sequential radiographs show the lesions migrating away from the growth-plate.4
These lesions have a distinct appearance on magnetic resonance imaging (MRI) and computed tomography (CT).
Both can...
Conclusion
Post-traumatic cyst-like lesions are rare complications of fractures in the paediatric population.
In most cases,
the typical radiographic appearance of a new cyst-like lesion near a healing fracture in a child should make the diagnosis and radiologist should be familiar with this tumor-like lesion.
If needed,
MR or CT can be used to confirm it and prevent unwarranted investigations.
References
1.
Asrian A,
Shahabpour M,
Tajdar F,
de Boeck H.
Posttraumatic cyst-like lesions of cortical bone in children.
Acta orthopaedica Belgica.
2010;76(2):264-8.
2.
Papadimitriou NG,
Christophorides J,
Beslikas TA,
Doulianaki EG,
Papadimitriou AG.
Post-traumatic cystic lesion following fracture of the radius.
Skeletal radiology.
2005;34(7):411-4.
3.
Beh JC,
Hamouda ES.
Paediatric post-traumatic osseous cystic lesion following a distal radial fracture.
Journal of radiology case reports.
2016;10(7):23-9.
4.
Roach RT,
Cassar-Pullicino V,
Summers BN.
Paediatric post-traumatic cortical defects of the distal radius.
Pediatric radiology.
2002;32(5):333-9.
5.
Little...