Treatments and Services
Selective Dorsal Rhizotomy
What is selective dorsal rhizotomy (SDR)?
Selective dorsal rhizotomy (SDR) is a surgery done on the lower spinal cord to reduce spasticity (high muscle tone) in the legs. Certain abnormal nerve fibers that cause high muscle tone are cut.
The goal of SDR is to relax the muscles by identifying and cutting only those nerve fibers that contribute to spasticity.
When it is followed by months of rehabilitation, SDR can improve your child's ability to move and control their muscles. This one-time surgery may reduce the need for future orthopedic surgeries.
Introduction to selective dorsal rhizotomy
This brief introduction to selective dorsal rhizotomy features the story of one patient, 3-year-old Arabelle, who had a selective dorsal rhizotomy to decrease spasticity related to cerebral palsy. (Part one of a five-part series.)
Spasticity is caused by a problem with communication between the brain and the spinal cord. This might be due to an earlier brain injury or for other reasons.
The message loop between the brain, the spinal cord, the nerves and the muscles doesn't function correctly. This makes the muscles tight.
During SDR, the surgical team carefully identifies and tests the sensory nerves to see exactly which ones are misfiring. Only nerves that aren't working well are cut, interrupting the message loop that was causing the spasticity. This provides a long-term improvement in muscle tone because the nerves do not grow back together.
Children who are already mobile
Children who have some mobility but whose progress is reduced due to spasticity may benefit from SDR.
Your child may be able to have SDR if they are somewhat able to walk, either with assistance or independently, and if their muscle stiffness is mainly in the legs (spastic diplegia). Both your child and your family must be able to participate in prolonged therapy following surgery. Your child must be able to follow directions from the therapists.
Children who are not mobile
SDR may be helpful for children who are not mobile and have spasticity in all limbs (spastic quadriplegia) due to traumatic brain injury, spinal cord injury or cerebral palsy.
If your child's spasticity makes it painful and difficult to provide daily care (for example, due to scissoring of the legs), SDR can permanently relieve the tightness of the leg muscles. This can make positioning and care such as diapering easier and can reduce your child's pain.
SDR is a one-time procedure. The cut nerves do not grow back, so the reduction in spasticity is permanent. Unlike other treatments, such as the baclofen pump, it does not typically require any follow-up surgeries.
Learn about the process we use to evaluate your child to see if SDR is a good fit. Rehabilitation physician Dr. Susan Apkon and neurosurgeon Dr. Samuel Browd discuss the team's approach, and what you can expect from the assessment. (Part two of a five-part series.)
How do I make an appointment?
- To make an appointment, email or call 206-987-5917.
- The Surgical Tone Management Clinic, a part of the Rehabilitation Medicine Department, does SDR evaluations.
- This clinic does not require a referral from your child’s doctor.
We will request your child’s medical records, including X-rays and other imaging before your child’s visit. The medical team will review these records before the evaluation.
How to refer
What happens during the surgery?
Your child will be asleep (given general anesthesia) during the surgery.
The neurosurgeon makes about a one-inch long cut (incision) in the middle of your child's low back.
Through this incision, the neurosurgeon makes a small window (laminectomy) in the spine to expose the nerve fibers.
The neurosurgeon identifies and separates the nerves that control motion (motor nerves) from the nerves that control feeling (sensory nerves). The motor nerves are shielded to ensure they aren't cut.
Then the team separates the sensory nerves into smaller bundles. Then, the neurosurgeon and an electrophysiologist use electrical stimulation to test the sensory nerves to find out which ones respond abnormally. This is called neurostimulation monitoring. The team will typically do about 80 stimulations to carefully decide which sensory nerves are behaving abnormally.
The neurosurgeon will cut a percentage of the abnormal nerves. Which nerves and how many are cut varies from child to child, but it is generally about 60% of the sensory nerve fibers. The percentage of nerves cut depends on the pre-operative assessment and the results from the neurostimulation monitoring.
The surgery typically takes about three hours. During your child's surgery, a nurse will call you from the operating room to give you regular updates.
Right after surgery, your child's neurosurgeon will meet with you to explain what was done and how it went. You will be able to be with your child after they leave the recovery room, about 45 minutes after the surgery is finished.
Neurosurgeon Dr. Samuel Browd describes how the selective dorsal rhizotomy surgery is done at Seattle Children's. Parent Christine Laddusaw shares what the experience was like for her and her daughter, Arabelle. (Part three of a five-part series.)
Your doctor will talk with you in detail about the benefits and risks of surgery. In general, the risks related to SDR include:
- Taking away too much tone, making the muscles too loose. We reduce this risk by carefully testing the individual nerve fibers and only cutting a percentage of the nerves.
- There is a small risk of a spinal fluid leak. To reduce this risk, your child will need to lie down flat for three days after surgery. This gives the thin, leather-like material (dura) that covers the spinal cord time to seal itself back up.
Your child will be weak right after surgery. When the misfiring nerves are cut, the underlying weakness of the muscles is revealed.
If your child was able to move independently before the surgery, they may have been relying on spasticity instead of actual muscle strength. So after surgery, your child may not be able to do certain things that they used to do, such as sit up without help or walk. Rehabilitation will help your child gain true strength and more efficient patterns of motion.
Some patients experience increased sensitivity in their feet after SDR. This usually goes away within a few months.
What happens after the surgery?
For the first three days after surgery, your child will need to lie flat.
If the aim of your child's surgery is to improve their ability to walk, your child will need to stay at Seattle Children's for two to three weeks of inpatient rehabilitation. This therapy will focus on increasing your child's strength and muscle control, with special focus on walking.
After going home from the hospital, your child will need outpatient therapy three to four times each week, for six to 12 months after surgery. This may be a combination of private therapy and school-based therapy. We will work with you and your child's therapists on the transition. Consistent therapy is important to help your child meet their goals following surgery.
If the goals for your child are focused more on ease of care and comfort measures, a five-day hospital stay is usually long enough to make sure their pain is well managed and that they are safely recovering from surgery.
Parent Christine Laddusaw reflects on the difference SDR and inpatient rehab have made for her daughter Arabelle. Dr. Susan Apkon and physical therapist Rachelle Steijn describe how we'll support you and your child in the transition home, and for the long term. (Part five of a five-part series.)
What's special about SDR at Seattle Children's?
Learn why inpatient rehabilitation is an essential part of SDR at Seattle Children's. Dr. Susan Apkon and physical therapist Rachelle Steijn describe the goals of therapy. Parent Christine Laddusaw shares how inpatient rehab made a difference for her daughter Arabelle. (Part four of a five-part series.)
Seattle Children's is the only hospital in the Pacific Northwest with the expertise to offer SDR and comprehensive inpatient rehabilitation. Our medical, surgical and rehabilitation experts will do a thorough evaluation to see if SDR is right for your child. Since you know your child best, we will work with you to develop and follow through on a therapy plan that is right for your child and for your family. A child life specialist, an expert in helping children understand and cope with medical procedures, can work with your child before or after surgery. Learn more about what to expect and preparing your child for surgery.
Dr. Samuel Browd performs every SDR at Seattle Children's. Browd is a board-certified pediatric neurosurgeon. Your child's sedation (anesthesia) will be provided by a board-certified pediatric anesthesiologist.
The procedure has been refined so that your child's surgical incision will be small, about one inch. The back of one vertebra (lamina) will be removed as part of the surgery.
When independent walking is the goal of your child's SDR, the surgical procedure is followed by two to three weeks of inpatient therapy in our Rehabilitation unit. This is essential to ensure that your child gets the maximum possible benefit of the surgery.
Our rehabilitation doctors, physical therapists and occupational therapists will work with you to design an individualized therapy plan based on your child's needs and your goals for your child.
Your child will have therapy every day, typically in the morning and the afternoon. Our therapists have a broad range of skills, so they can respond to your child's individual needs and adjust your child's treatment as they improve.
We understand that play is a child's most important job. All of the post-surgery rehabilitation is done using play. Your child's physical and occupational therapists will work therapy into things your child likes to do. A music therapist may work with them to include music-based activities.
A therapeutic recreation specialist will work with your child to make sure they are getting back to the activities they most enjoy. This helps keep your child engaged and making progress.
Pediatric psychologists are available to help if your child is having a hard time adjusting to the hospital stay.
Because your child's therapy will need to continue several days a week once you go home from the hospital, we will involve you in their treatment on a daily basis. Our therapists will help you learn how to help your child get the most benefit from the SDR.
We do our best to make sure you have what you need to make your inpatient stay manageable. Your child's room has a sleeper chair or couch where one parent or guardian can sleep at night. If you need it, our Guest Services team will help you find transportation or a place to stay.
In order for your child to get the most benefit from the SDR, they will need to continue therapy after going home. We will work with you to find appropriate therapy resources in your community. If you already have therapists at home, we will coordinate with them.