Imaging

Standard imaging here includes x-rays in two planes. It shows a sharply defined lesion centered in the bone. A typical sign in X-rays is the “falling fragment sign”.

In this case a collapsed fragment protrudes into the fluid-filled cavity. In addition, a CT or MRI can be performed to obtain even more precise information about the juvenile bone cyst. In addition to X-rays, the MRI is another, more precise procedure in the diagnosis of a juvenile bone cyst.

The juvenile bone cyst is presented in the MRI as a lesion that is filled with fluid and not “chambered”, i.e. it does not contain several spaces that can be separated from each other. In exceptional cases, however, an atypical septum may be present, i.e. the chamber is separated by a thin septum. The MRI is additionally used in the diagnosis of a juvenile bone cyst, as it offers the advantage of being able to delimit the extent of the bone cyst very well and thus determine its exact size.

Furthermore, the actual presence of fluid can only be verified with the MRI. In general, however, the MRI is not always absolutely necessary, since an X-ray image can be meaningful enough to diagnose a juvenile bone cyst. In addition to the fluid-filled cavity, the cyst wall can be described in more detail in the MRI. In this case a tender cyst capsule without nodular changes is characteristically visible. An edema, i.e. an accumulation of fluid around the bone cyst, is only present if a fracture of the affected bone has already occurred secondarily.

Differential diagnoses

Although it may be a juvenile bone cyst, imaging alone is often not sufficient and other causes of a pathological fracture must be ruled out based on the clinic and any further diagnostic measures. A pathologic fracture is a bone fracture that occurs spontaneously without external influence.These other causes include: Aneurysmatic bone cyst, abscess, giant cell tumor, fibrous dysplasia (a malformation of bone tissue), chondromyxoid fibroma;