Project Summary
This project is ongoing and does not have results.
The Patient-Centered Outcomes Research Institute (PCORI) is partnering with the Agency for Healthcare Research and Quality (AHRQ) to develop a systematic evidence review on Diagnosis and Treatment of Tethered Spinal Cord. The Congress of Neurological Surgeons (CNS) nominated the topic to PCORI and plans to use the findings of the systematic evidence review to develop related clinical guidelines.
Background
Tethered spinal cord (TSC) is a rare neurological condition in which natural movement of the spinal cord within the spinal column is limited by tissue attachments that cause abnormal strain. Its incidence is estimated at 0.25 per 1,000 births. TSC is closely associated with spina bifida and many children with spina bifida are treated for TSC.
Symptoms are usually progressive and often begin in childhood during periods of growth--exposing the underlying congenital condition. However, symptoms can also emerge in adulthood due to clinical scenarios that enhance flexion/extension movements that further stress a spinal cord under tension, such as pregnancy, sports injury or age-related change; these circumstances either aggravate and unmask the previously unknown congenital condition or newly create the condition. At the same time, some individuals with confirmed tissue attachments never develop symptoms. Symptoms may include leg weakness, numbness or pain; gait changes or difficulty walking; bowel and/or bladder incontinence; scoliosis or disability. Individuals with suspected tethered cord may undergo one or more imaging studies to aid in diagnosis.
Treatment generally involves surgical intervention. Surgically detethering attached tissues within the spinal column is the primary surgical technique. However, multiple surgical techniques are described in the literature and treatment patterns vary across the U.S. Furthermore, recurrent symptoms may occur due to scar tissue that can envelop functional nerve roots that make complete untethering challenging without causing new neurological injury. Spinal column shortening is an indirect detethering surgery which shortens and fuses the spine to relieve longitudinal pressure on the spinal cord. Sometimes, the spinal cord nerve roots are cut. Symptoms often stabilize or improve after surgery; however, retethering (along with renewed symptoms) may reoccur especially during rapid growth or due to new scar tissue formation. This requires additional treatment decisions.
The ideal timing of treatment is not always clear. Some patients receive prophylactic detethering in infancy before symptoms emerge while others undergo detethering surgery in childhood or young adulthood when symptoms begin. Delay in diagnosis or treatment in symptomatic individuals can lead to permanent issues and/or disability and must be weighed against the risks and benefits of surgery.
Available Literature
There are no current guidelines based on a high-quality systematic review that comprehensively cover the proposed Key Questions (KQ). The 2020 European Association of Urology (EAU)/European Society for Paediatric Urology (ESPU) guidelines on the management of neurogenic bladder in children and adolescents is grounded in a systematic review; however, it is primarily focused on timing of treatment and management of neurogenic bladder symptoms. Three other clinical recommendation documents published since 2017 are based on expert clinical consensus and convenings.
The topic needs a high-quality, up-to-date systematic review of the evidence. A handful of systematic reviews peripheral to the topic have been published since 2017 but no one review summarizes all the proposed KQs nor do any of the reviews adequately summarize any one KQ comprehensively. Conducting RCTs on this condition and population is difficult and much of the research is found in observational studies. Consequently, only a few randomized controlled trials (RCT) pertaining to treatment therapies have been published recently, although many recent comparative observational studies may provide evidence for the proposed review.
The lack of evidence synthesis and clinical guidance is a challenge when navigating the complex decisions around diagnosis, timing of treatment, type of treatment and follow-up care for TSC. A new systematic review and eventual updated care guidelines in this area could significantly benefit patients, families, caregivers, physicians and researchers.
Proposed Key Questions (KQs)
1. What is the accuracy of radiographic and other diagnostic criteria in diagnosing tethered spinal cord?
2. What are the benefits and harms of prophylactic surgery for asymptomatic tethered spinal cord treatment?
3. What are the effectiveness, comparative effectiveness and harms of surgical and non-surgical treatments for symptomatic tethered spinal cord?
3a. Stratified by symptom intensity and age?
3b. Are effects modified by use of special surgical equipment or techniques?
4. Among individuals who experience retethering after spinal detethering surgery, what are the benefits, harms and long-term outcomes of another surgery compared with no treatment?
4a. Are individual factors with which a patient presents (such as primary symptoms, symptom intensity, age, etc.) associated with better or worse outcomes after repeat surgery?