Aneurysmal Bone Cyst

An aneurysmal bone cyst is a benign blood-filled lesion that forms on the bone.

Although aneurysmal bone cyst aren’t cancerous and don’t spread, they still need to be treated, since they can grow and expand the bone and cause it to fracture. When this happens, it can cause pain, swelling, deformity and could disrupt growth or cause neurological issues. There are 2 types of ABCs:

  • Active: Can deform the bone it’s growing in, while remaining contained in the bone

  • Aggressive: Will extend beyond the bone, into soft connective tissue and typically require treatment


The cause of an aneurysmal bone cyst is unknown.


Common signs and symptoms related to aneurysmal bone cysts are:

  • Swelling at the site of the cyst

  • Stiffness

  • Mild to severe neurological problems if cyst is on the spine

  • Fractures


To determine if your child has an aneurysmal bone cyst, your specialized doctor may perform a number of tests to determine the size, location, and severity of the cyst. The tests may include:

  • Imaging tests such as X-rays, MRIs, or CT scans or angiography

  • Physical examination

  • Biopsy


Your doctor will determine the best treatment based on your child’s age, overall health, location of the cyst and other factors. Your child’s doctor will discuss all options for the best outcome for your child.Surgical TreatmentIt’s important to be aware that your child may need several different treatments, including surgery. There are different procedures a surgeon may use, such as bone grafting or curettage, which involves scraping out the bone to remove the cyst.

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