Posttraumatic cranial cystic fibrous dysplasia

Area of Science:

• Neuroscience
• Orthopedics
• Pathology

Background:

• Fibrous dysplasia (FD) is a bone disorder where normal bone is replaced by fibrous tissue.
• Cranial involvement in FD can present with diverse radiographic findings.
• The etiology of FD, particularly cranial FD, remains incompletely understood, with potential links to genetic factors and environmental influences.

Observation:

• A 14-year-old female presented with a 6-year history of a growing subcutaneous occipital mass, following a head injury at age 6.
• Radiological imaging, including X-ray, CT, and MRI, revealed a bony defect and cystic changes in the skull correlating with the mass.
• Bone scintigraphy showed partial tracer accumulation in the affected area.

Findings:

• Surgical excision of the cranial mass was performed.
• Pathological examination of the cyst wall confirmed the diagnosis of fibrous dysplasia (FD).
• This case suggests a potential association between cranial FD and prior head trauma, a link not previously reported.

Implications:

• The findings suggest that head trauma may play a role in the pathogenesis or progression of cranial fibrous dysplasia.
• Understanding the relationship between injury and FD, possibly involving mechanisms like c-fos gene expression, could lead to new insights.
• This case underscores the importance of considering trauma history in the evaluation of cranial bone abnormalities and FD.