National Board of Chiropractic Examiners (NBCE) Practice Test

A lytic expansile lesion in the neural arch of a vertebra resembling a giant cell tumor in long bones is most likely which of the following?

1. Aneurysmal bone cyst

2. Osteoid osteoma

3. Nonossifying fibroma

4. Giant cell tumor

The correct answer is: Aneurysmal bone cyst

A lytic expansile lesion in the neural arch of a vertebra that resembles a giant cell tumor in long bones is most accurately identified as an aneurysmal bone cyst. This type of lesion typically presents in young individuals and is characterized by blood-filled spaces leading to a locally aggressive behavior with expansion of the affected bone. Aneurysmal bone cysts are often found in the vertebral column and can appear similar to giant cell tumors due to their lytic nature and expansile growth pattern, but they are distinct entities. In contrast to other conditions listed, an aneurysmal bone cyst is specifically associated with the expansive and destructive characteristics observed in the neural arch of vertebrae. The other choices refer to different types of bone lesions. Osteoid osteoma, for example, is a small, painful lesion typically found in long bones and is not expansive or lytic in the same way. Nonossifying fibromas are benign lesions often seen in children typically located in the metaphysis of long bones, and giant cell tumors, while notable for aggressive lytic behavior, are usually found in the metaphysis around the knee rather than the neural arch of vertebrae. Thus, their presentations do not match the described characteristics of the lesion in