Research and Advances
What is limb-sparing surgery?
Limb-sparing surgery, also called limb salvage, is a treatment for malignant bone tumors.
Unlike many surgical procedures for malignant bone tumors, it gives your child a chance to keep the limb in which a tumor is located.
Because malignant bone tumors can spread cancer cells to the rest of your child’s body, doctors treat the tumors by removing them. In the past, this usually meant removing the child’s limb, often a leg, along with the tumor.
Limb-sparing surgery saves your child’s limb by removing only the tumor and surrounding bone and cartilage.
Once we remove the tumor and surrounding tissue, we use either bone transplants called allograft bone grafts or metal implants, such as knee joint replacements, in place of the bone we remove.
When young children are still growing, we can sometimes use a recently developed device called a growing prosthesis that expands while inside your child to match her growth.
How do you evaluate patients for limb-sparing surgery?
To gather information about your child’s condition and see if she might be able to have limb-sparing surgery, we look at many images of the bone that has the tumor. We ask your child to have imaging tests before and after chemotherapy and before we take the tumor out.
Doctors at Children’s Hospital were pioneers in the use of the PET scan and the MRI (magnetic resonance imaging) to see if chemotherapy has shrunk a patient’s tumors before surgery.
This helps us know how much bone and tissue we should remove along with the tumor during surgery. It also helps us assess bone healing after a bone graft and implant procedures.
Who gets limb-sparing surgery?
Children and teenagers with osteosarcoma and Ewing sarcoma can benefit from limb-sparing surgery. But whether your child is a candidate for the operation depends on several factors, including the size of her tumor, its location and how much it has spread.
Limb-sparing surgery may not be an option if the tumor is too close to a major nerve or artery. In addition, before surgery your child must respond well to chemotherapy that shrinks the tumor.
Finally, she must have enough soft tissue and skin to allow the wound to heal after surgery.
Growing prostheses for young children
Children younger than age 10 who have a tumor face an additional challenge. Because they are still growing, we must surgically lengthen their affected leg as they get older so it matches their healthy leg.
At Seattle Children’s, we are using a new technique called growing prostheses that can make it possible for young children to have limb-sparing surgery even if we must remove a tumor in or near a growth plate in their leg bones.
Growing prostheses use an acrylic implant that, when exposed to an electromagnetic field, partially melts. As the implant softens, a spring releases that stretches the child’s bone. This technique may decrease the number of surgeries your child will need to lengthen her affected leg.
At present, we use this technique only in children younger than age 10 — the patients who need the most limb lengthening.
What is your experience with limb-sparing surgery?
Our Pediatric Bone Tumor and Sarcoma Program was the first interdisciplinary program in the nation, and our dedicated team has focused on bone tumors in children for more than 20 years.
We have performed more than 400 limb-sparing procedures for young patients who come from throughout the United States.
What is involved in limb-sparing surgery?
Your child will first have a biopsy to confirm she is a good candidate for limb-sparing surgery. Then she will have chemotherapy to shrink the tumor before surgery.
During surgery, your child’s doctor will remove the affected part of the bone and replace it with an implant — either a bone transplant or a metal prosthesis.
One of the most challenging parts of limb-sparing surgery is matching the implant to your growing child. In some cases, children need several procedures that lengthen their implants to keep up with normal growth.