Posttraumatic cysts after pediatric fracture

Pediatric postfracture cystic bone lesions are most commonly found on routine follow-up radiographs of distal radius fractures. After their discovery, there is often a discussion of the need for further radiologic imaging or operative intervention.

We present 3 cases in which all the 3 pediatric patients had a history of a healing fracture and had the lesions diagnosed incidentally on average 3 months after initial injury.

These similar cases demonstrate the nearly identical radiographic characteristics of postfracture cystic lesions of the distal radius. The radiographs consistently demonstrate a well-circumscribed lytic lesion without surrounding sclerosis (geographic 1B) within the elevated periosteum of the healing fracture. These lesions appeared to sit on top of the previous cortex without causing any erosion or having any other aggressive characteristics. All of the lesions were consistent with adipose tissue on all sequence including T1, T2, and fat-suppressed T1-weighted imaging.

Although postfracture pediatric cysts are apparently rare, we feel that there is sufficient literature to support that there is no longer any need for advanced imaging modalities to diagnose these lesions in the setting of an appropriate history without confounding variables and classic radiographic appearance. Biopsy, in particular, is decidedly unnecessary, unless the lesion progresses on subsequent radiographs or demonstrates more overtly aggressive initial features.

This will allow for faster diagnosis with substantially less burden on the health care system and decreased the stress that is placed on the patients and families involved by requiring magnetic resonance imaging with or without conscious sedation in order to make the final diagnosis.

IV-case series.