A surgery called SPR (selective posterior rhizotomy), combined with personalized rehabilitation therapy, “unshackled” the legs of a 9-year-old boy with cerebral palsy. His gait changed from toe-walking to steady walking, and his knees became straight rather than flexed while walking.

To treat the symptoms but not the root cause ？

Xiao Wei (pseudonym), a pediatric patient, was still unsteady when walking and fell easily at 16 months of age. After examination at the hospital, he was diagnosed with cerebral palsy. When he was two years old, his family brought him to begin rehabilitation treatment. At that time, he walked with a toe-walking gait, and his language development lagged behind that of children of the same age. So far, the rehabilitation treatment has produced poor results.

Does rehabilitation treatment merely “treat the symptoms but not the root cause” and therefore have little effect? Many parents of children with cerebral palsy and other brain disorders have this concern.

In response, Professor Xiao Hong said that regarding the issue of “treating the symptoms but not the root cause,” we need to take into account that each child’s individual circumstances are different, which leads to differences in the effectiveness of rehabilitation treatment; therefore, it cannot be said to be completely ineffective. The MDT multidisciplinary collaborative diagnosis and treatment model adopted by the Neurosurgery Department of our hospital allows pediatric patients to consult experts from multiple disciplines in one visit. Experts from neurosurgery, neurology, orthopedic surgery, rehabilitation medicine, and other related disciplines jointly conduct comprehensive assessment and full-cycle management of the disease, enabling patients to receive more precise diagnosis and treatment.

Surgery + Rehabilitation: A Powerful Combination

In mid-December 2024, in order to seek further treatment, Xiao Wei’s family brought the child to the Department of Neurosurgery of Shenzhen Overseas Chinese Hospital.

Professor Xiao Hong, former Director of the Department of Neurosurgery at Huiya Hospital of the First Affiliated Hospital of Sun Yat-sen University and Director of the Department of Minimally Invasive Neurosurgery at Shenzhen Overseas Chinese Hospital, learned during his initial consultation with the child that the child could now communicate and answer questions relevantly, but had poor logical thinking and memory. Physical examination revealed that the child still walked unsteadily with a toe-walking gait; needed to hold handrails when going up and down stairs; could not squat with heels together; had knee flexion in both lower limbs and bilateral foot inversion.

Based on specialized physical examination and assessment, the diagnoses were cerebral palsy, bilateral Achilles tendon contracture, bilateral acquired talipes equinovarus, and bilateral hip joint contracture.

Through an MDT multidisciplinary consultation in the Department of Neurosurgery of our hospital, experts from multiple disciplines jointly discussed the patient’s treatment plan and formulated an individualized treatment plan. It was decided to first adopt surgery, namely selective posterior rhizotomy (SPR), to improve the child’s lower limb muscle tone and toe-walking gait; postoperative rehabilitation treatment would be combined to correct the walking gait and consolidate the surgical effect.

During surgery, an incision of only 4 cm was made at the lumbar spine. With the aid of intraoperative neurophysiological monitoring, the abnormal nerve fibers causing spasticity were precisely located and cut.
“SPR surgery is not a one-size-fits-all cut; it is as precise as defusing a bomb,” Professor Xiao Hong explained. Under electrophysiological monitoring, a midline incision was made in the lumbosacral region, preserving the facet joints on both sides. The dura mater was opened, and the exit points of the L3–S1 nerve roots on both sides were identified. After carefully separating the anterior and posterior roots, microsurgical instruments were used to divide each posterior root of L3–S1 into several small bundles, usually five. The stimulating electrode of an electromyography or electrical stimulator was used to hook each posterior rootlet, and the stimulation threshold of each posterior rootlet was measured in sequence. The “limb movement method” was used to observe the nerve stimulation threshold, that is, the nerve threshold at which the corresponding muscle showed spastic contraction during electrical stimulation. Rootlets with low thresholds were selected, and a 5-mm segment was excised with microsurgical scissors.

Surgery is only the starting point; postoperative rehabilitation is equally crucial.

After a period of postoperative rehabilitation, Xiao Wei’s lower limb muscle tone decreased, his toe-walking disappeared, and his walking gait improved markedly. His knees could bend and straighten, and his walking became steady.

Xiao Wei’s rehabilitation process demonstrates the importance of individualized treatment plans. From walking on tiptoes to walking steadily, the child’s transformation reflects the power of medical progress. With the wider adoption of innovative technologies such as SPR surgery, more legs once “sealed” may take a step that changes their destiny.

SPR

SPR is currently the main surgical procedure for relieving spasticity. It selectively blocks some posterior root fibers, thereby modulating intrafusal muscle fibers and reducing muscle tone, without affecting the anterior nerve roots that control muscle strength. Moreover, the procedure requires surgery only in the lumbar region to relieve spasticity in both lower limbs. It does not interfere with rehabilitative training to restore leg muscle strength and can effectively address the “rehabilitation” bottleneck, thereby facilitating the recovery of patients’ limb function.

Indications for SPR Surgery

Lumbar SPR surgery is mainly indicated for patients with spastic cerebral palsy or limb spastic paralysis caused by other causes.

If the following conditions are met, lumbar SPR can be performed directly (except in special circumstances).

a. Age > 2.5 years;
b. Able to lift the leg steadily (muscle strength ≥ grade III), preferably able to lift the leg against resistance;
c. Definite increase in limb muscle tone;
d. Able to walk independently (gross motor function at GMFCS level I–III);
e. Good balance function (negative on the passive balance test), which is very critical;
f. The child is able to cooperate with postoperative rehabilitation training.

The primary goal of lumbar SPR surgery is to relieve lower limb spasticity and bring abnormal muscle tone closer to normal, thereby improving limb motor function in children with cerebral palsy.

Conditions Improved by SPR Surgery

SPR is a one-time surgical procedure that permanently reduces muscle tone, and it is currently the primary and preferred surgical approach for relieving limb spasticity. The following are the main problems that SPR surgery can improve:

1. Reduce muscle tone and relieve muscle spasms.

Image source: Internet

SPR selectively severs some group Ia nerve fibers in the posterior roots of the spinal nerves and partially interrupts the gamma loop that regulates muscle tone, thereby reducing limb muscle tone, preserving muscle strength, and improving spasticity. Extensive clinical evidence has confirmed that SPR can provide long-term relief from muscle spasticity. When combined with perioperative and long-term physical therapy, it can significantly and effectively improve patients’ motor function.

2. Improve joint range of motion and limb function.

By reducing muscle tone, SPR surgery can increase joint range of motion and improve limb flexibility. This enables patients to better control their limbs and perform daily activities such as walking and grasping.

3. Correct abnormal gait and posture.

Patients with cerebral palsy often develop abnormal gait and posture due to hypertonia, such as scissor gait, foot inversion, and toe-walking. By relieving spasticity, SPR surgery helps correct these abnormal gait patterns and postures, making patients’ walking more natural and coordinated.

4. Create Better Conditions for Subsequent Rehabilitation Training.

By reducing muscle tone, SPR surgery provides a better foundation for patients’ subsequent rehabilitation training. After surgery, patients can more effectively undergo physical therapy, motor training, and other rehabilitation measures, further improving limb function and motor ability, reducing the degree of disability, and enhancing quality of life. While relieving spasticity, SPR surgery helps patients reduce their dependence on assistive devices.

Is there an age requirement for SPR surgery?

Whether there is an age requirement for performing SPR surgery is a question of great concern. The following is a specific explanation of the age requirements for SPR surgery:

Age requirement for lumbar SPR surgery — Lumbar SPR can be performed in patients older than 2.5 years.

As an effective treatment method, SPR surgery (functional selective posterior rhizotomy) can effectively reduce muscle tone, improve limb function, gait, and posture, and create favorable conditions for subsequent rehabilitation training, bringing hope to many patients with cerebral palsy.