Selective Dorsal Rhizotomy Procedures


What is a Selective Dorsal Rhizotomy?

Selective dorsal rhizotomy is a nerve surgery that permanently decreases high muscle tone, or spasticity. During a rhizotomy, a surgeon cuts specific nerves in the spinal canal contributing to the child’s spasticity. A multi-disciplinary team of experts – including pediatric specialists in neurosurgery, physical medicine and rehabilitation, orthopedics, neurology, physical therapy and others – evaluates each child and their specific needs and goals. This may involve assessment in our state-of-the-art Motion Analysis Lab, which gives detailed information on a child’s gait that helps guide decision making. 

Several different variations of the rhizotomy procedure may be tailored to each child’s needs. Discussions with our Spasticity Management care team help patients and families choose the procedure that works best for them.

Types of Rhizotomy Procedures

At Texas Children’s Hospital, the most common rhizotomy procedures performed are: 

  • Selective Dorsal Rhizotomy (SDR) 
    • Full SDR 
    • Focal SDR
  • Palliative Rhizotomy 

A summary of each procedure’s goals, qualifications, method, incision size and recovery expectations are shown in this table.

Summary of Rhizotomy Procedures


Focal SDR 


Full SDR


Palliative Rhizotomy 

Surgery Goals 


Reduce spasticity in specific muscle groups to improve gait and mobility Reduce spasticity throughout the legs to improve gait and mobility Provide comfort, improve positioning, improve ease of care
Who Qualifies Children who need tone reduction in only a few muscles, typically at the ankle or knee level Children who walk and have high muscle tone evenly distributed in their legs Children who do not walk or use their legs to stand or transfer
Method Nerve roots accessed through tube; minimal bone is removed Nerve roots accessed by unroofing vertebrae Single-level access with a customized percent of sensory and/or motor nerves cut
Incision Size 2 cm Variable 5-8 cm
Recovery Expectations
  • Overnight inpatient stay, with outpatient physical rehab program
  • Recovery in 1-2 days with minimal discomfort
  • 2-5 day inpatient stay
  • 2-3 week inpatient rehab program followed by outpatient therapies
  • Recovery over months
  • No therapy needed
  • Reassessment of equipment needs
  • Transfer training with physical therapy

We’ve described the procedures in greater detail here:

Full Selective Dorsal Rhizotomy

In a full selective dorsal rhizotomy (SDR), the surgeon accesses the nerves that supply the leg muscles (L2 to S1). This is done via laminoplasty, or temporarily opening the vertebrae from the back. Selective means that the neurosurgeon cuts specific nerve roots at the levels causing the spasticity. Dorsal refers to the location of the nerves in the spinal canal. The dorsal nerves have small branches called “rootlets” that send messages toward the spine. During surgery, these rootlets are stimulated, and the most abnormal rootlets are cut. This decreases the spasticity reflex loop and relaxes muscles in the legs. Nerve monitoring during surgery keeps unaffected nerves safe. 

After recovering for a few days after surgery, patients are transferred to Texas Children’s Inpatient Rehabilitation Unit to continue strengthening and gait training. In appropriate candidates, this surgery can be transformative in improving a child’s gait, allowing them to walk with greater independence and ease.

Is a selective dorsal rhizotomy the right procedure for your child? 

It can be the right solution for children with high muscle tone. Your health care team will guide you through the decision process. The child’s likelihood of meeting an SDR surgery’s goals are shown in this overview:

Chance of Meeting SDR Surgery Goals

High Chance Lower Chance 
  • Spasticity is the main cause of high muscle tone 
  • Good strength 
  • Good motor control 
  • Can understand and comply with instructions 
  • Can complete the rehabilitation program 
  • Dystonia is the main cause of stiffness 
  • Weakness 
  • Poor motor control 
  • Can’t follow instructions 
  • Can’t complete the rehabilitation program


View of a Full SDR

Focal Selective Dorsal Rhizotomy

A focal SDR is a minimally invasive method of reducing tone in only one or two nerve levels. Children who require spasticity reduction in only a few muscles, typically at the ankle or knee, may be candidates for focal SDR. Through a 1-inch incision, the surgeon removes a tiny piece of bone and uses a small tube to access, view, and cut nerve rootlets at 1 or 2 nerve levels. Children usually recover from this surgery in 1 to 2 days, then participate in our Acute Outpatient Rehabilitation Program.

Focal SDR may be performed simultaneously to orthopedic surgery, such as heel cord release. This allows the child to recover from both procedures at the same time and undergo only one operation. This procedure has broadened access to the benefits of rhizotomy to a wider group of patients. This includes patients with diverse etiologies of spasticity, older kids and young adults, and patients with a range of cognitive capabilities.

Palliative Rhizotomy 

A palliative rhizotomy can reduce muscle tone in children who do not walk or use their legs to stand or transfer. This type of rhizotomy reduces involuntary high muscle tone – spasticity, dystonia or both – to make the child more comfortable. The resulting reduction in stiffness makes positioning and caregiving easier. This may involve sectioning of sensory nerve roots, or both sensory and motor nerve roots. A palliative rhizotomy may be needed to reduce muscle tone enough before an orthopedic procedure. For example, children who have severe spasticity and weakness often have dislocated hips. If the underlying high muscle tone remains and a surgeon realigns the hip, the hip joint may come out of position again. 

Why Choose Texas Children’s Hospital

At Texas Children’s, any child being considered for a rhizotomy will meet with our entire team during the first clinical visit. Together, we will discuss details of the child’s condition, our proposed treatment plan, recovery timing and other important details. We use state-of-the-art technology and sophisticated surgical techniques to ensure the best possible outcomes for our patients.  

Our multidisciplinary Spasticity team includes: 

  • Physical medicine and rehabilitation doctors 
  • Neurosurgeons 
  • Orthopedic surgeons 
  • Physical therapists 
  • Advanced practice providers 
  • Registered nurses 
  • Social workers 
  • Custom bracing experts 

We are internationally recognized for our surgical expertise, performing more than 1,000 operations including selective dorsal and other rhizotomies.