Guideline summary review: an evidence-based clinical guideline for the diagnosis and treatment of adult isthmic spondylolisthesis

BACKGROUND CONTEXT

The North American Spine Society's (NASS) Evidence-Based Clinical Guideline for the Diagnosis and Treatment of Adult Isthmic Spondylolisthesis features evidence-based recommendations for diagnosing and treating adult patients with isthmic spondylolisthesis. The guideline is intended to reflect contemporary treatment concepts for symptomatic isthmic spondylolisthesis as reflected in the highest quality clinical literature available on this subject as of June 2013. NASS' guideline on this topic is the only guideline on adult isthmic spondylolisthesis accepted in the Agency for Healthcare Research and Quality's National Guideline Clearinghouse.

PURPOSE

The purpose of the guideline is to provide an evidence-based educational tool to assist spine specialists when making clinical decisions for adult patients with isthmic spondylolisthesis. This article provides a brief summary of the evidence-based guideline recommendations for diagnosing and treating patients with this condition.

STUDY DESIGN

This is a guideline summary review.

METHODS

This guideline is the product of the Adult Isthmic Spondylolisthesis Work Group of NASS' Evidence-Based Clinical Guideline Development Committee. The methods used to develop this guideline are detailed in the complete guideline and technical report available on the NASS website. In brief, a multidisciplinary work group of spine care specialists convened to identify clinical questionsto address in the guideline. The literature search strategy was developed in consultation with medical librarians. Upon completion of the systematic literature search, evidence relevant to the clinical questions posed in the guideline was reviewed. Work group members utilized NASS evidentiary table templates to summarize study conclusions, identify study strengths and weaknesses, and assign levels of evidence. Work group members participated in webcasts and in-person recommendation meetings to update and formulate evidence-based recommendations and incorporate expert opinion when necessary. The draft guidelines were submitted to an internal peer review process and ultimately approved by the NASS Board of Directors. Upon publication, the Adult Isthmic Spondylolisthesis guideline was accepted into the National Guideline Clearinghouse and will be updated approximately every 5 years.

RESULTS

Thirty-one clinical questions were addressed, and the answers are summarized in this article. The respective recommendations were graded according to the levels of evidence of the supporting literature.

CONCLUSIONS

The evidence-based clinical guideline has been created using techniques of evidence-based medicine and best available evidence to aid practitioners in the diagnosis and treatment of adult patients with isthmic spondylolisthesis. The entire guideline document, including the evidentiary tables, literature search parameters, literature attrition flowchart, suggestions for future research, and all of the references, is available electronically on the NASS website at https://www.spine.org/ResearchClinicalCare/QualityImprovement/ClinicalGuidelines.aspx and will remain updated on a timely schedule.

[Spondylolysis and spondylolisthesis in children and adolescents]

Low back pain is a common cause of lost playing time in young athletes, and spondylolysis is its most common identifiable cause. Despite technological advances in radiology, which can lead to an early diagnosis with better prognosis, progression to spondylolisthesis is sometimes asymptomatic and may not be detected until late stages. There are wide variations, suggesting lack of consensus as regards the objective of treatment, which consists of clinical, radiological, biomechanical or functional improvement. There is also a lack of agreement regarding the ideal conservative treatment, surgical indications and need of slip reduction, and most of the established recommendations are not evidence based. We present a review of literature, which summarizes the current knowledge of spondylolysis and spondylolisthesis in children and adolescents.

Magnetic resonance imaging and magnetic resonance myelography in the presurgical diagnosis of lumbar foraminal stenosis

STUDY DESIGN

Retrospective case series with a control group.

OBJECTIVE

To measure the diagnostic performance of magnetic resonance imaging (MRI) and MR myelography (MRM) for symptomatic foraminal stenosis in patients who need surgery.

SUMMARY OF BACKGROUND DATA

MR images are extensively used in the evaluation of foraminal stenosis and are often used to evaluate nerves exiting from the foramen. There has been no published report of the diagnostic performance of these imaging methods (MRI and MRM).

METHODS

Diagnostic performances were studied in 90 patients in whom the site of the stenosis was confirmed by means of selective decompression surgeries. The disease prevalence among patients was 26% (23 of 90 patients). The disease prevalence among foramens was 3% (25 of 936 foramens). The prevalence of abnormal findings in 27 asymptomatic volunteers was also studied. Two blinded observers interpreted foraminal narrowing on combinations of sagittal and axial MR images, abnormalities of the course of the nerve root in the foramen, and spinal nerve swelling on MRM.

RESULTS

The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of MRI for the diagnosis of symptomatic foraminal stenosis were 96%, 67%, 4%, and 100%, respectively. The corresponding values for abnormal nerve root course on MRM were 96%, 83%, 7%, and 100%, respectively, and for spinal nerve swelling on MRM were 60%, 99%, 35%, and 99%, respectively.

CONCLUSIONS

Compared with conventional MRI, MRM affords more specific information for the presurgical diagnosis of symptomatic foraminal stenosis.

Long-term outcome after posterolateral, anterior, and circumferential fusion for high-grade isthmic spondylolisthesis in children and adolescents: magnetic resonance imaging findings after average of 17-year follow-up

STUDY DESIGN

A cross-sectional study to evaluate the long-term result of posterolateral (PLF), anterior (AF), and circumferential fusion (CF) for isthmic spondylolisthesis.

OBJECTIVES

To assess the long-term effects of PLF, AF, or CF for high-grade isthmic spondylolisthesis on lumbar spine in children and adolescents by using MRI.

SUMMARY OF BACKGROUND DATA

Short- and mid-term clinical and plain radiographic results of isthmic spondylolisthesis and of PLF, AF, and CF in severe slip are well documented. The long-term effect of the fusion on soft tissues, on the intervertebral discs inside and above fusion in particular, is, however, unclear.

METHODS

Between 1977 and 1991, PLF (n = 21), AF (n = 22), or CF (n = 24) was performed on 67 patients (42 females, 25 males) with high-grade (slip > or =50%) isthmic spondylolisthesis. The average age of patients at the time of operation was 14.4 (range, 8.9-19.6) years. Clinical, spinal mobility and trunk strength in addition to MRI and plain radiograph examinations were performed on these patients after an average follow-up time of 17.3 years (range, 10.7-26.0 years).

RESULTS

Three (14%) patients in the PLF and AF groups, but none in the CF group, reported back pain often or very often at rest. The mean Oswestry Disability Index (ODI) was 9.7 (range, 0-62) in the PLF, 8.1 (0-32) in the AF, and 2.3 (0-14) in the CF group (P < 0.05). The mean slip before surgery was 66% (range, 50%-100%) and at the last follow-up visit 66% (range, 26%-106%). Disc degeneration was most common in the PLF group (P = 0.0014) and inside the fusion and in the lowest moving intervertebral disc spaces in all subgroups. Only 1 patient had an asymptomatic prolapse. In MR images, none of the patients had lumbar central canal stenosis inside or above the fusion. In contrast, the spinal canal was wide at the spondylolysis and spondylolisthesis level in 23 (34%) patients. Of the patients, 19 (28%) patients (32 neural foramens) had severe narrowing of the neural foramen with impingement of the nerve root. No patients had clinically confirmed L5 nerve root symptoms. Muscle degeneration was found in 29 (43%) of patients. Longer fusion and muscle degeneration, but not disc degeneration, were associated with lower performance in spinal mobility and trunk-strength measurement tests.

CONCLUSIONS

The clinical outcome was best in the CF group as measured by ODI. Degenerative changes were most commonly found at the level of the slip and above the fusion level. The prevalence of disc prolapses was low. Spinal fusion for isthmic spondylolysis is not associated with central canal stenosis above the fusion. Radiologic nerve root stenosis was common but asymptomatic. Mild muscle atrophy was common.

Treatment of severe spondylolisthesis in adolescence with reduction or fusion in situ: long-term clinical, radiologic, and functional outcome

STUDY DESIGN

Retrospective follow-up study with two cohorts: one treated with reduction and the other with fusion in situ.

OBJECTIVE

To assess the long-term effects of reduction versus fusion in situ on lumbar spine in children and adolescents with severe L5 isthmic spondylolisthesis.

SUMMARY OF BACKGROUND DATA

Severe isthmic spondylolisthesis is commonly treated with fusion in situ, but modern surgical techniques and instrumentation permit the reduction of a severely slipped fifth lumbar vertebra. Advocates of one or another of these procedures present different claims to defend their choice. However, to our knowledge, no long-term results of the reduction maneuver exist.

METHODS

Between 1983 and 1991, 22 adolescents with severe (more than 60%) slip were treated surgically. In 11 of them, reduction was performed with a Magerl/Dick transpedicular device, followed by fusion posteriorly from L4 or L5 to S1 and anteriorly from L5 to S1. In the others, fusion was performed in situ posteriorly from L4 (n = 7) or L5 (n = 4) to S1 and anteriorly from L5 to S1. The average age of patients at surgery was 14.7 years (range 10.7-18.5). Radiographs obtained before surgery, after surgery, and at the final follow-up evaluation were assessed for quality of fusion. In addition, magnetic resonance imaging was obtained at the last follow-up visit. Average follow-up time was 14.8 years (range 11.6-18.7). Physical examination, spinal mobility, and nondynamometric trunk strength measurements were used to assess, and Oswestry Disability Index and Scoliosis Research Society scores were used to calculate outcome at the last follow-up visit.

RESULTS

In the reduction group, mean Oswestry Disability Index was 7.2 (range 0-20) and in the fusion in situ group, was 1.6 (range 0-4) (P = 0.0096). The Scoliosis Research Society total score averaged 90.0 (range 39-107) in the reduction group and 103.9 (range 93-120) in the fusion in situ group (P = 0.046). At the last follow-up evaluation, mean vertebral slip had decreased from the preoperative value of 90% to 57% in the reduction group but remained the same (80% vs. 78%) in the fusion in situ group (P = 0.04 and 0.013, respectively, for preoperative and postoperative comparison). On magnetic resonance imaging, disc degeneration above the fusion was more common in the reduction group (P = 0.004). None of the patients had spinal stenosis above the fusion. Nerve root canal impingement at the L5-S1 level was more common in the fusion in situ group (P = 0.03), but all patients were free of L5 nerve root symptoms. There was no difference in spinal mobility or trunk strength measurements between the groups.

CONCLUSIONS

The fusion in situ group seems to perform better in almost all clinical parameters measured. These findings suggest that fusion in situ should be considered as a method of choice in severe L5 isthmic spondylolisthesis.

No correlation between patient outcome and abnormal lumbar MRI findings 21 years after posterior or posterolateral fusion for isthmic spondylolisthesis in children and adolescents

Between 1977 and 1987, posterior (n=29) or posterolateral (n=73) fusion was performed for mild to moderate (slip <50%) isthmic spondylolisthesis on 102 patients (46 females, 56 males). The patients' average age at the time of operation was 15.9 (range, 8.1-19.8) years. Clinical (physical examination and Oswestry disability index (ODI)) and radiological (MRI and plain radiographs) examinations were performed on these patients after an average follow-up time of 21.0 (range, 26.2-15.1) years. In the radiographs, the mean slip preoperatively was 27% (range, 5-50%) and at the last follow-up visit 26% (range, 5-78%). Inside the fusion, there were a total of 148 intervertebral discs, 121 (82%) of them had decreased signal intensity in T2-weighted MR images and 113 (76%) were narrowed. Above the fusion level, 27 (27%) discs were speckled and 27 (27%) were black; 21 (21%) intervertebral disc spaces were narrowed. Two levels above the fusion level the numbers were 8 (8%), 16 (16%) and 16 (16%), respectively. Six (6%) patients had a prolapse. Degenerative facet joint hypertrophy above fusion was seen at 80 (79%) of the levels studied. When compared to healthy subjects higher frequency of disc and facet joint degeneration was found. In MR images, none of the patients had lumbar spinal stenosis inside or above the fusion. Narrowing of one or both of the neural foramina at the level of the L5-S1 interververtebral disc was noted in 32 (31%) patients. Seventeen (17%) of the patients had, usually mild, muscular atrophy of the psoas and 33 (32%) of the paraspinal muscles. There was no difference in frequency of abnormal MRI findings between patients (n=93) with ODI 20 or less compared with patients (n=9) with ODI more than 20. In situ fusion due to isthmic spondylolsthesis at adolescence is associated with moderate degenerative changes in the lumbar spine during a 20-year follow-up. Changes were most commonly found at the level of the spondylolisthesis and above fusion level. Neural foramina stenosis seems to be associated with spondylolisthesis and its severity to severity of the slip. Muscle atrophy tended to be mild. However, there was no correlation between patient outcome (ODI) and abnormal lumbar MRI findings.

The Course of the Nerve Root in the Neural Foramen and Its Relationship with Foraminal Entrapment or Impingement in Adult Patients with Lumbar Isthmic Spondylolisthesis and Radicular Pain

The purpose of this study was to demonstrate the course of a nerve root in the neural foramen and its relationship with foraminal entrapment or impingement in 19 adult patients with isthmic spondylolisthesis and radicular pain. Myelo-computed tomography and magnetic resonance imaging showed that the course of the nerve root was normal (ie, medial and then inferior, along the pedicle) in 10 patients and was deviated posteriorly in 9 patients. The patients with a normal nerve root course (N-NRC) had either a bony callus projecting medially into the spinal canal (n = 6) or a low mean percentile of vertebral slip (n = 4; 13.9 +/- 1.3). Those nine patients with a posteriorly deviated nerve root course (PD-NRC) had no medially projecting bony callus in the spinal canal but had a higher mean percentile of vertebral slip (n = 9; 31.5 +/- 10.1; P = 0.005). In the neural foramen, nerve roots of the N-NRC patients were entrapped craniocaudally between the pedicle and superior part of the intervertebral disc. In contrast, nerve roots of the PD-NRC patients were impinged ventrodorsally between the posterosuperior part of the intervertebral disc and either bony callus projecting inferiorly toward the neural foramen or fibrocartilaginous mass arising around the isthmic defect. The foraminal craniocaudal entrapment and ventrodorsal impingement highly agreed with the side of radicular pain (kappa= 0.73, P < 0.001). Our results demonstrate that the medially projecting bony callus and the percentile of vertebral slip affect the course of the nerve root in the neural foramen, which in turn determines the foraminal craniocaudal entrapment or ventrodorsal impingement. These two mechanisms, based on the course of the nerve root, correlate well with the side of radicular pain.

The imaging of lumbar spinal stenosis

Lumbar spinal stenosis (LSS) is a relatively common condition of varied aetiology which results in chronic compression of the cauda equina. It becomes clinically relevant when giving rise to symptoms of neurogenic claudication or leg pain. Lumbar spinal stenosis can be classified based on anatomy or aetiology and the diagnosis in any single case should include a consideration of both the site and the cause. Plain radiography is of limited value. Myelography with erect lateral flexion/extension views will demonstrate the dynamic component of the stenosis which cannot be appreciated on plain computed tomography (CT) or magnetic resonance imaging (MRI). Therefore, in patients with a good history of symptomatic LSS, and a borderline stenosis on MRI, CT myelography is recommended as the definitive pre-operative imaging investigation.

Isthmic lumbar spondylolisthesis with sciatica: the role of the disc

Thirty-one patients with isthmic spondylolisthesis were investigated using MR imaging. Twenty-one of these patients had selectively unilateral sciatica and no abnormalities on adjacent discs. In 18 patients there was a clear correlation between the degree of foraminal stenosis and the symptomatic side. In 20 patients there was evidence of root compression by disc tissue.

Posterolateral lumbar fusion. Outcome of 71 consecutive operations after 4 (2-7) years

We report the outcome of 71 consecutive posterolateral lumbar fusions without spinal instrumentation. The indication for the operation was spondylolysis-olisthesis, degenerative disc disease/facet joint arthrosis, or pain after prior laminectomy. Concerning pain relief, 29/43 patients with spondylolysis-olisthesis were classified as good. The corresponding figures in the group with degenerative disc disease and/or facet joint arthrosis were 8/16 patients and in the group with pain post-laminectomy, 6/12 patients. No surgical complications were noted. In the total material 54 patients had a solid fusion, as defined by radiographic osseous trabecular bridging at all intended levels. One-level fusions tended to heal solidly in a higher frequency than two-level fusions. For the spondylolysis-olisthesis group, healed fusion correlated with a good clinical result. Such a correlation could not be verified for the other diagnostic groups. We conclude that non-instrumented posterolateral lumbar fusion is a valid method for treating low-grade spondylolysis-olisthesis, especially when the aim is to fuse a single level. Improved patient selection methods are required in fusion for degenerative disc disease and pain after laminectomy.

Disc herniation in lumbar spondylolisthesis. Report of 3 symptomatic cases

Because of its rarity, we present the case histories of three patients with a painful lumbar disc herniation in spondylolytic spondylolisthesis. The herniations were diagnosed by MRI and CT. Two of the herniations were confirmed at surgery, and one was treated conservatively.