Unicameral Bone Cysts (UBC’S)

A unicameral bone cyst, often known as a simple bone cyst, is a benign bone tumor. These tumors are mostly commonly found near the shoulder and hip joints.  Unique to children, they usually go away without treatment after your child has completed the growth cycle.

For over 150 years, physicians have been treating children for this condition. Treatment today can range from observation to surgical removal of the cyst. The cause of these simple bone cysts is still unknown.

Although these cysts are benign and usually go away with time, they can still lead to problems. They have the potential to weaken bone and cause it to break. These breaks can be painful for children and sometimes require surgery to treat the pain or the fractures.

Diagnosis

These cysts are usually found in one of three ways:

1. Bone fracture.  Sometimes these fractures can be treated with a cast and the cyst can be observed until a later date. Other times, the fracture can involve critical areas, like the hip. In these cases, your surgeon will likely recommend surgery for your child to prevent future growth complications.
   
   
2. Complaint of pain. If your child has pain in a particular area, an x-ray can reveal a cyst. If a cyst can be seen from an x-ray, likely, a fracture is about to occur. This is the probably the reason your child is feeling pain. Surgery to remove the cyst is often needed to prevent the fracture from happening.
   
   
3. Incidentally. Occasionally, x-rays may be performed for one reason, and a cyst with no prior symptoms happens to be seen on the x-ray unexpectedly.  In this event, treatments options vary per case and by physician.

Treatment

Traditionally, orthopaedic surgeons have treated the cysts by injecting them with steroids to reduce the size. Unfortunately, results show that the cysts often back more than 70% of the time. At Children’s Orthopaedics of Atlanta (COA) a different technique is used in which the cyst is literally “scraped out” and then filled with calcium pellets using minimally invasive surgery. The calcium pellets are used to help stimulate healing. At COA, this has actually decreased the recurrence rate of the cysts down to about 30%. Once your child has been treated for these cysts, it is important that they continue to see their doctor, even if there is no pain, to ensure it does not come back.