An evidence-based clinical guideline for the diagnosis and treatment of degenerative lumbar spinal stenosis (update).

BACKGROUND CONTEXT: The evidence-based clinical guideline on the diagnosis and treatment of degenerative lumbar spinal stenosis by the North American Spine Society (NASS) provides evidence-based recommendations to address key clinical questions surrounding the diagnosis and treatment of degenerative lumbar spinal stenosis. The guideline is intended to reflect contemporary treatment concepts for symptomatic degenerative lumbar spinal stenosis as reflected in the highest quality clinical literature available on this subject as of July 2010. The goals of the guideline recommendations are to assist in delivering optimum efficacious treatment and functional recovery from this spinal disorder. PURPOSE: Provide an evidence-based educational tool to assist spine care providers in improving quality and efficiency of care delivered to patients with degenerative lumbar spinal stenosis. STUDY DESIGN: Systematic review and evidence-based clinical guideline. METHODS: This report is from the Degenerative Lumbar Spinal Stenosis Work Group of the NASS's Evidence-Based Clinical Guideline Development Committee. The work group consisted of multidisciplinary spine care specialists trained in the principles of evidence-based analysis. The original guideline, published in 2006, was carefully reviewed. A literature search addressing each question and using a specific search protocol was performed on English language references found in MEDLINE, EMBASE (Drugs and Pharmacology), and four additional, evidence-based, databases to identify articles published since the search performed for the original guideline. The relevant literature was then independently rated by a minimum of three physician reviewers using the NASS-adopted standardized levels of evidence. An evidentiary table was created for each of the questions. Final recommendations to answer each clinical question were arrived at via work group discussion, and grades were assigned to the recommendations using standardized grades of recommendation. In the absence of Levels I to IV evidence, work group consensus statements have been developed using a modified nominal group technique, and these statements are clearly identified as such in the guideline. RESULTS: Sixteen key clinical questions were assessed, addressing issues of natural history, diagnosis, and treatment of degenerative lumbar spinal stenosis. The answers are summarized in this document. The respective recommendations were graded by the strength of the supporting literature that was stratified by levels of evidence. CONCLUSIONS: A clinical guideline for degenerative lumbar spinal stenosis has been updated using the techniques of evidence-based medicine and using the best available clinical evidence to aid both practitioners and patients involved with the care of this condition. The entire guideline document, including the evidentiary tables, suggestions for future research, and all references, will be available electronically at the NASS Web site (www.spine.org) and will remain updated on a timely schedule.

Radiculopathy in degenerative lumbar scoliosis: correlation of stenosis with relief from selective nerve root steroid injections.

OBJECTIVE: The purpose is to define the origin of radiculopathy of patients with degenerative lumbar scoliosis-stenosis and to assess the correlation between percentage of initial radicular leg pain relief with selective nerve root injections and lateral canal dimensions. DESIGN: Retrospective clinical study. SETTING AND PATIENTS: Thirty-six consecutive patients (average age 72) from Twin Cities Spine Center with degenerative lumbar scoliosis (average major curve 25°) and radicular symptoms were studied. INTERVENTIONS: Patients underwent 46 selective steroid injections of nerve roots concordant with clinical symptomatology. OUTCOME MEASURES: Radiographic measurements included major and lumbosacral curve Cobb angle. Computerized measurements of magnetic resonance imaging (MRI) included minimum subarticular height and foramen cross-sectional area of the nerve roots that were injected. Initial response from the nerve root injections was also rated. RESULTS: Twenty-five percent of nerve root symptoms were coming from the major curve, 72.2% from the lumbosacral hemicurve and 2.8% from both (P<0.001). The affected nerve roots were more frequently the L4 (34.8%) and L5 (28.3%) nerve roots. A total of 71.7% of radicular symptoms were originating from the concavity of the curve and 28.7% from the convexity (P<0.001). The relief from injections was more than 50% in 75% of the patients at 15 days postinjection. There was no statistical significant correlation (P>0.05) between the lateral canal dimensions and the initial response to injection of anesthetic plus steroid injection. CONCLUSIONS: In degenerative lumbar scoliotic curves, radicular symptoms are attributed mainly to nerve roots exiting from the concavity of the lumbosacral hemicurve. No evidence was found that the rate of initial relief from selective nerve root injections correlates with the degree of stenosis noted in the MRI.

An evidence-based clinical guideline for the diagnosis and treatment of cervical radiculopathy from degenerative disorders.

BACKGROUND CONTEXT: The North American Spine Society (NASS) Evidence-Based Clinical Guideline on the Diagnosis and Treatment of Cervical Radiculopathy from Degenerative Disorders provides evidence-based recommendations on key clinical questions concerning the diagnosis and treatment of cervical radiculopathy from degenerative disorders. The guideline addresses these questions based on the highest quality clinical literature available on this subject as of May 2009. The guideline's recommendations assist the practitioner in delivering optimum efficacious treatment of and functional recovery from this common disorder. PURPOSE: Provide an evidence-based educational tool to assist spine care providers in improving quality and efficiency of care delivered to patients with cervical radiculopathy from degenerative disorders. STUDY DESIGN: Systematic review and evidence-based clinical guideline. METHODS: This report is from the Cervical Radiculopathy from Degenerative Disorders Work Group of the NASS' Evidence-Based Clinical Guideline Development Committee. The work group consisted of multidisciplinary spine care specialists trained in the principles of evidence-based analysis. Each member of the group formatted a series of clinical questions to be addressed by the group. The final questions agreed on by the group are the subjects of this report. A literature search addressing each question using a specific search protocol was performed on English language references found in MEDLINE, EMBASE (Drugs and Pharmacology), and four additional evidence-based databases. The relevant literature was then independently rated by a minimum of three reviewers using the NASS-adopted standardized levels of evidence. An evidentiary table was created for each of the questions. Final recommendations to answer each clinical question were arrived at via work group discussion, and grades were assigned to the recommendations using standardized grades of recommendation. In the absence of Levels I to IV evidence, work group consensus statements have been developed using a modified nominal group technique, and these statements are clearly identified as such in the guideline. RESULTS: Eighteen clinical questions were formulated, addressing issues of natural history, diagnosis, and treatment of cervical radiculopathy from degenerative disorders. The answers are summarized in this article. The respective recommendations were graded by the strength of the supporting literature, which was stratified by levels of evidence. CONCLUSIONS: A clinical guideline for cervical radiculopathy from degenerative disorders has been created using the techniques of evidence-based medicine and best available evidence to aid both practitioners and patients involved with the care of this condition. The entire guideline document, including the evidentiary tables, suggestions for future research, and all references, is available electronically at the NASS Web site (www.spine.org) and will remain updated on a timely schedule.

Functional and radiological outcomes of 360 degrees fusion of three or more motion levels in the lumbar spine for degenerative disc disease.

STUDY DESIGN: This is a single-center, multisurgeon, retrospective study of radiologic and functional outcome measures at a minimum 2-year follow-up. OBJECTIVE: We studied the radiologic and functional outcomes following 3 or more motion segment fusions of the lumbar spine for low back pain due to multilevel degenerative disc disease. SUMMARY OF BACKGROUND DATA: Good functional outcomes have been reported for 1 or 2-level fusions, but there are no reports dealing specifically with 3 or more level fusions. METHODS: A total of 80 adult patients met the inclusion/exclusion criteria of multilevel (3 or more motion segments) 360 degrees fusion for lumbar degenerative disc disease, failed nonoperative treatment for at least 1 year, no previous lumbar fusion, no fracture, tumor or infection of the spine, completed preoperative and postoperative functional questionnaires including SF-36 (n = 80), Oswestry (n = 69), Roland Morris (n = 68), and radiologic evaluation of fusion solidity with a minimum follow-up of 2 years. RESULTS: The average patient age was 57 years (range, 27-81). The mean follow-up was 4 years (2-7). On average, patients had fusion of 4 motion segments (range, 3-8 levels). Solid arthrodesis at the first surgery was achieved in 65/80 (81%). Adjacent segment degeneration was noted in 11 patients. Of these, 5 had undergone an extension of their fusion within the study period. There were no deaths or neurologic complications. Deep wound infection occurred in 2 patients, neither requiring implant removal. The Oswestry Disability Index scores improved from 49.8 to 35.1 (29.5%) (P < 0.001). The Roland Morris scores improved from 17.6 to 12.2 (30.7%) (P < 0.001). For the SF-36 scales, significant (P < 0.001) improvement was seen in all scales except Role Emotional scores and Mental Composite Scales. CONCLUSION: The surgical treatment of lumbar degenerative disc disease by 360 degrees fusion should be considered for properly selected patients. The goal of surgery is reduction, not elimination of disability.

An evidence-based clinical guideline for the diagnosis and treatment of degenerative lumbar spondylolisthesis.

BACKGROUND CONTEXT: The objective of the North American Spine Society (NASS) evidence-based clinical guideline on the diagnosis and treatment of degenerative lumbar spondylolisthesis is to provide evidence-based recommendations on key clinical questions concerning the diagnosis and treatment of degenerative lumbar spondylolisthesis. The guideline is intended to address these questions based on the highest quality clinical literature available on this subject as of January 2007. The goal of the guideline recommendations is to assist the practitioner in delivering optimum, efficacious treatment of and functional recovery from this common disorder. PURPOSE: To provide an evidence-based, educational tool to assist spine care providers in improving the quality and efficiency of care delivered to patients with degenerative lumbar spondylolisthesis. STUDY DESIGN: Systematic review and evidence-based clinical guideline. METHODS: This report is from the Degenerative Lumbar Spondylolisthesis Work Group of the NASS Evidence-Based Clinical Guideline Development Committee. The work group was comprised of multidisciplinary spine care specialists, all of whom were trained in the principles of evidence-based analysis. Each member participated in the development of a series of clinical questions to be addressed by the group. The final questions agreed on by the group are the subject of this report. A literature search addressing each question and using a specific search protocol was performed on English language references found in MEDLINE, EMBASE (Drugs and Pharmacology) and four additional, evidence-based, databases. The relevant literature was then independently rated by at least three reviewers using the NASS-adopted standardized levels of evidence. An evidentiary table was created for each of the questions. Final grades of recommendation for the answer to each clinical question were arrived at via face-to-face meetings among members of the work group using standardized grades of recommendation. When Level I-IV evidence was insufficient to support a recommendation to answer a specific clinical question, expert consensus was arrived at by the work group through the modified nominal group technique and is clearly identified as such in the guideline. RESULTS: Nineteen clinical questions were formulated, addressing issues of prognosis, diagnosis, and treatment of degenerative lumbar spondylolisthesis. The answers to these 19 clinical questions are summarized in this document. The respective recommendations were graded by the strength of the supporting literature that was stratified by levels of evidence. CONCLUSIONS: A clinical guideline for degenerative lumbar spondylolisthesis has been created using the techniques of evidence-based medicine and using the best available evidence as a tool to aid practitioners involved with the care of this condition. The entire guideline document, including the evidentiary tables, suggestions for future research, and all references, is available electronically at the NASS Web site (www.spine.org) and will remain updated on a timely schedule.

Clinical and radiological outcome of anterior-posterior fusion versus transforaminal lumbar interbody fusion for symptomatic disc degeneration: a retrospective comparative study of 133 patients.

Abundant data are available for direct anterior/posterior spine fusion (APF) and some for transforaminal lumbar interbody fusion (TLIF), but only few studies from one institution compares the two techniques. One-hundred and thirty-three patients were retrospectively analyzed, 68 having APF and 65 having TLIF. All patients had symptomatic disc degeneration of the lumbar spine. Only those with one or two-level surgeries were included. Clinical chart and radiologic reviews were done, fusion solidity assessed, and functional outcomes determined by pre- and postoperative SF-36 and postoperative Oswestry Disability Index (ODI), and a satisfaction questionnaire. The minimum follow-up was 24 months. The mean operating room time and hospital length of stay were less in the TLIF group. The blood loss was slightly less in the TLIF group (409 vs. 480 cc.). Intra-operative complications were higher in the APF group, mostly due to vein lacerations in the anterior retroperitoneal approach. Postoperative complications were higher in the TLIF group due to graft material extruding against the nerve root or wound drainage. The pseudarthrosis rate was statistically equal (APF 17.6% and TLIF 23.1%) and was higher than most published reports. Significant improvements were noted in both groups for the SF-36 questionnaires. The mean ODI scores at follow-up were 33.5 for the APF and 39.5 for the TLIF group. The patient satisfaction rate was equal for the two groups.

Degenerative lumbar spinal stenosis: an evidence-based clinical guideline for the diagnosis and treatment of degenerative lumbar spinal stenosis.

BACKGROUND CONTEXT: The objective of the North American Spine Society (NASS) evidence-based clinical guideline for the diagnosis and treatment of degenerative lumbar spinal stenosis (DLSS) is to provide evidence-based recommendations to address key clinical questions surrounding the diagnosis and treatment of DLSS. The guideline is intended to reflect contemporary treatment concepts for symptomatic DLSS as reflected in the highest quality clinical literature available on this subject as of April 2006. The goals of the guideline recommendations are to assist in delivering optimum, efficacious treatment, and functional recovery from this spinal disorder. PURPOSE: To provide an evidence-based tool that assists practitioners in improving the quality and efficiency of care delivered to patients with DLSS. STUDY DESIGN/SETTING: Evidence-based clinical guideline. METHODS: This report is from the Spinal Stenosis Work Group of the NASS Clinical Guidelines Committee. The work group comprised medical, diagnostic, interventional, and surgical spinal care specialists, all of whom were trained in the principles of evidence-based analysis. In the development of this guideline, the work group arrived at a consensus definition of a working diagnosis of lumbar spinal stenosis by use of a modification of the nominal group technique. Each member of the group formatted a series of clinical questions to be addressed by the group and the final list of questions agreed on by the group is the subject of this report. A literature search addressing each question and using a specific literature search protocol was performed on English language references found in MEDLINE, EMBASE (Drugs and Pharmacology), and four additional, evidence-based, databases. The relevant literature to answer each clinical question was then independently rated by at least two reviewers using the NASS-adopted standardized levels of evidence. An evidentiary table was created for each of the questions. Any discrepancies in evidence levels among the initial raters were resolved by at least two additional members' review of the reference and independent rating. Final grades of recommendation for the answer to each clinical question were arrived at in face-to-face meetings among members of the work group using the NASS-adopted standardized grades of recommendation. When Levels I to IV evidence was insufficient to support a recommendation to answer a specific clinical question, expert consensus was arrived at by the work group through the modified nominal group technique and is clearly identified as such in the guideline. RESULTS: Eighteen clinical questions were asked, addressing issues of prognosis, diagnosis, and treatment of DLSS. The answers to these 18 clinical questions are summarized in this document along with their respective levels of evidence and grades of recommendation in support of these answers. CONCLUSIONS: A clinical guideline for DLSS has been created using the techniques of evidence-based medicine and using the best available evidence as a tool to aid both practitioners and patients involved with the care of this disease. The entire guideline document including the evidentiary tables, suggestions for future research, and all references is available electronically at the NASS Web site (www.spine.org) and will remain updated on a timely schedule.

Is it safer to place pedicle screws in the lower thoracic spine than in the upper lumbar spine?

STUDY DESIGN: An anatomic study of 100 patients comparing the pedicle isthmic width of the lower thoracic spine and the upper lumbar spine using magnetic resonance imaging. OBJECTIVES: To compare the lower thoracic pedicles and upper lumbar pedicles in nondeformity patients as a surrogate measure of safety of pedicle screw use. SUMMARY OF BACKGROUND DATA: Pedicle isthmic width is the significant limiting factor in the safety and proper placement of transpedicular screws. The presumption in the past has been that the lumbar pedicles are larger than the thoracic pedicles. Few publications in the English-language literature specifically evaluate the association between the pedicle isthmic widths of the lower thoracic and upper lumbar. METHODS: The study evaluates 100 patients, without coronal spinal deformities. MRIs were obtained of the pedicles from T10 to L2 and subsequently measured using the axial T2-weighted views. Lower thoracic and upper lumbar pedicle isthmus, the narrowest section of pedicle, was investigated and compared. The "medial pedicle to medial rib corridor" at T10-T12 was defined and measured as part of the methodology of the study. Statistical analysis included one-way analysis of variance with post hoc least significant difference pairwise comparisons. RESULTS: The smallest pedicle isthmic width was at L1 (mean +/- SD, 6.0 +/- 1.6 mm), while T12 (mean +/- SD, 7.6 +/- 1.5 mm) had the largest pedicle width. Although smaller in diameter than T12, both T10 (mean +/- SD, 6.2 +/- 1.2 mm) and T11 (mean +/- SD, 7.5 +/- 1.6 mm) had larger pedicle width than L1 (P < 0.01). Pedicle widths were larger in males compared with females (P < 0.05). CONCLUSIONS: The results show that the lower thoracic pedicles are larger than the upper lumbar pedicles. This may make it safer to place screws in the lower thoracic spine than in the upper lumbar spine. Upper lumbar may be so small (<5 mm) to preclude safe conventional screw placement.

Degenerative lumbar scoliosis: radiographic correlation of lateral rotatory olisthesis with neural canal dimensions.

STUDY DESIGN: A radiographic review of 78 consecutive patients with degenerative rotatory lumbar scoliosis. OBJECTIVE: To assess the correlation between rotary olisthesis and neural canal dimensions using radiographic indexes and to establish a gradation system of lateral rotatory olisthesis. SUMMARY OF BACKGROUND DATA: Degenerative scoliosis is a three-dimensional deformity often associated with spinal stenosis, although the association is not well defined. METHODS: A total of 78 consecutive patients (average age, 69 years) with de novo degenerative scoliosis (79% lumbar, 21% thoracolumbar; average curve, 25 degrees) were studied with plain radiographs and MRI at presentation. Radiographic measurements included lateral translation, anteroposterior olisthesis, Cobb angle, and intervertebral rotation (Nash-Moe grade difference). Computerized measurements of MRI included dural sac cross-sectional area and anteroposterior diameter, minimum subarticular height, and foramen cross-sectional area bilaterally (convexity and concavity). Measurements were conducted twice on each lumbar level (total, 312) and the average was recorded. RESULTS: Lateral translation 5 mm or less (Grade I) was associated with Nash-Moe change 0 (23%) or I (77%), lateral translation 6-10 mm (Grade II) was coupled with Nash-Moe change 0 (20%) or I (80%) and lateral deviation more than 11 mm (Grade III) was associated with I (76%) or II (24%) Nash-Moe change. Maximum intervertebral rotation tended to be at either L2-L3 (48%) or L3-L4 (39%). Increased lateral translation was associated with increased intervertebral rotation (r = 0.37, P < 0.001). Increased anteroposterior olisthesis was associated with decreased anteroposterior diameter (r = -0.18, P < 0.001) and cross-sectional area (r = -0.11, P < 0.05) of the dural sac. Larger segmental Cobb angles were associated with greater foraminal cross-sectional area in the convexity (r = 0.12, P < 0.05). In the concavity, there was no significant correlation (P > 0.05) between indexes of rotary olisthesis and foraminal area or subarticular height. Cross-sectional foraminal area and subarticular height were significantly larger in the convexity than in the concavity of the scoliotic levels. CONCLUSIONS: In degenerative scoliotic curves, lateral translation is associated with rotation. Increased rotary olisthesis does not lead to decreased dural sac area. Anteroposterior olisthesis is inversely correlated to the dural sac anteroposterior diameter and cross-sectional area. With increased segmental Cobb angle, foraminal cross-sectional area enlarges in the convexity and does not decrease in the concavity. Presence of intervertebral rotation alone does not appear to be associated with reduced neural canal dimensions. Ligamentum flavum hypertrophy, posterior disc bulging, and bony overgrowth are more likely to contribute to stenosis irrespective of scoliosis.

Pedicle anatomy in a patient with severe early-onset scoliosis: can pedicle screws be safely inserted?

OBJECTIVE: With the rapid increase in the use of pedicle screws in the thoracic spine for various pathologies, knowledge of the pedicle anatomy is critical. Previous authors, in discussing pedicle morphology, have usually reported their findings in nondeformed adult specimens. More recently, the use of pedicle screws in adolescent idiopathic scoliosis has been reported. METHODS: The authors studied the pedicle diameters in the spine of a patient with infantile idiopathic scoliosis who died at age 28 of cor pulmonale. The concave pedicles from T6 to L3 were measured both directly and with thin-section computed tomography (CT) scanning (the curve apex was T8-T11). RESULTS: By direct measurement, the concave pedicle width at its narrowest point (the isthmus) ranged from 2.9 (T9) to 6.7 (L1, L3) mm. Three apical concave pedicles (T8, T9, T10) had no cancellous cavity. By CT scan measurement, the four apical concave pedicles measured 3.4 (T8), 2.8 (T9), 2.6 (T10), and 3.4 (T11) mm, respectively. CONCLUSIONS: In conclusion, the authors confirm others' findings that the concave pedicles can be so small that pedicle screw insertion is impossible. We also found that these findings can be confirmed preoperatively with thin-section CT scanning. In such situations, extrapedicular screw placement should be considered.