Unicameral Bone Cyst

A unicameral bone cyst (UBC) is a cavity in a bone that’s filled with fluid instead of with bone. UBC is a common, non-cancerous tumor found in children that occurs in one location of one bone.

Cause

The cause of unicameral bone cyst is unknown.

Symptoms

Common signs and symptoms related to unicameral bone cysts are:

• Pain when participating in weight-bearing activities from thinning of the bone
• Fracture caused by the disease
• Pain, swelling and/or deformity at the location of the cyst
• In some cases, no symptoms are present

Diagnosis

To determine if your child has a unicameral bone cyst, your specialized doctor may order imaging tests like X-rays or CT scans.

Treatment

Non-Surgical

A UBC without pain or other symptoms that the doctor discovers when evaluating another problem can be watched with repeated X-rays and routine doctor exams. Bone fractures caused by the cyst occasionally incite a healing process not requiring surgical intervention.

Your doctor may recommend treating UBC by draining the cyst (aspiration) and injecting it with a steroid or with bone graft from the bone bank, supplemented occasionally with bone marrow from the person’s pelvis. This method of treatment may require more than one aspiration/injection.

Surgical

Surgery is recommended when:

• UBCs have weakened your child’s bone and may cause a fracture
• UBC is painful, growing larger or in a location that may fracture

Types of surgical treatments:

• A doctor may recommend treating UBC by draining the cyst (aspiration) and injecting it with a steroid or with bone graft from the bone bank, supplemented occasionally with bone marrow from the person’s pelvis. This method of treatment may require more than one aspiration/injection.
• The doctor may treat it by draining the cyst (aspiration) and injecting it with a steroid or with bone graft from the bone bank, supplemented occasionally with bone marrow from the person’s pelvis. This method of treatment may require more than one aspiration/injection.
• If the cyst is causing weakness in your child’s bone, they may need surgery to scrape the inside of the bone (curettage). The hole left following this may require donor bone or a bone graft substitute to fill the defect. Depending on the size and location of the cyst, treatment with an internal fixation device (metal plates, pins, wires or screws) may also be needed.

See More Information

Bone Tumors