Degenerative Lumbar Spinal Stenosis Research Articles

Relationship between the benefits of paraspinal mapping and diffusion tensor imaging and the increase of decompression levels determined by conventional magnetic resonance imaging in degenerative lumbar spinal stenosis

BackgroundIn lumbar spinal stenosis (LSS), at most times, several levels are impaired and selecting the correct level remains a common problem for surgeons, as surgery remains invasive, and extended laminectomy may lead to secondary surgical complications. Therefore, helping to select the correct level may be useful for surgeons. The use of diffuse tensor imaging (DTI) and paraspinal mapping (PM) in addition to conventional magnetic resonance imaging (MRI) may be helpful (Chen et al., J Orthop Surg Res 11:47, 2016). However, with decompression levels determined by conventional magnetic resonance imaging (MRI) increasing, whether the benefits of reducing decompression level of conventional MRI + (DTI or PM) will be more obvious is unknown.MethodsReduced surgical levels that were different between levels determined by conventional MRI + (DTI or PM) and conventional MRI + neurogenic examination (NE) between groups were compared. Treatment outcome measures were performed at 2 weeks, 3 months, 6 months, and 12 months postoperatively.ResultsThe reduced levels of three groups showed no statistically significant differences between each other except for two levels and four levels (two levels/three levels, p = 0.085; two levels/four levels, p = 0.039; three levels/ four levels, p = 0.506, respectively).ConclusionsWith surgical levels determined by conventional MRI increasing, the benefits of DTI and PM will be uncertainly more obvious.

Short Lumbosacral Decompression Plus Fixation Does Not Change the Spinopelvic Balance on Patients With Moderate Degenerative Spondylolisthesis and Associated Spinal Stenosis

Study DesignA retrospective cohort study. ObjectivesTo investigate whether decompression plus short segment lumbosacral fixation changes the sagittal baseline spinopelvic parameters in patients with moderate degenerative spondylolisthesis (DS) and associated degenerative lumbar spinal stenosis (DLSS). Summary of Background DataSpinal decompression and fusion are commonly performed in DS with associated DLSS. Spinopelvic alignment after surgery for DS is an important research topic. The effect of short lumbosacral instrumented fusion on the global sagittal spinal balance has not been sufficiently studied. MethodsThirty-four consecutive adult patients (21 women, 13 men) aged 62 ± 11 years with balanced spines [sagittal vertical axis (SVA) ≤ 40 mm] received decompression and two to three vertebrae fixation plus fusion for DS grades I and II, associated with symptomatic DLSS. Age, gender, number of segments fused, posterolateral fusion (PLF) versus PLF plus posterior lumbar interbody fusion (PLIF) and segmental lordosis (SL) in the free segment above instrumentation were studied for a minimum follow-up of 60 months. The roentgenographic variables measured are T12–S1 lumbar lordosis (LL), SVA, sacral slope (SS), pelvic tilt (PT), pelvic incidence (PI), SL, and anterior (ADH) and posterior disc height (PDH) in the suprajacent free lumbar segment. Clinical outcomes were assessed with visual analog scale and Oswestry Disability Index. ResultsSVA significantly (p = .05) decreased postoperatively but returned to the baseline value at the final observation. Younger individuals (≤59 years) stood with greater SS (p = .036) 6 months postoperatively and with less SVA in all 3 periods of observation (p = .013, .046, and .024) than their older (>59 years) counterparts. Patients with monosegmental stenosis showed on baseline less SVA (p = .028), PT (p = .031), and PI (p = .004) than their two-segmental stenosis counterparts. PI preoperatively to the last evaluation was significantly smaller in the patients who received 360° fusion (p<.016). ConclusionsShort lumbosacral fixation does not significantly change the preoperative sagittal spinopelvic balance in adult patients with preoperatively balanced spines who have DS and DLSS. Level of EvidenceLevel III.

Outcomes of two minimally invasive decompressive techniques for degenerative lumbar spinal stenosis

Background Minimally invasive decompressive procedures have evolved into the modern standard surgical solution for degenerative lumbar spinal stenosis (DLSS) patients, such as the bilateral laminotomy and the unilateral laminotomy for bilateral decompression (ULBD) that is characterized by ipsilateral and contralateral microdecompression under the midline posterior structures and has been successfully used with proven efficacy. Objective To compare the effect of the size of the skin incision and the method of handling the multifidus muscle on the clinical outcomes of the endoscopic laminotomy versus the standard microscopic laminotomy for DLSS. Patients and methods Primary outcome data included the numerical rating scale for back and leg symptoms and Oswestry Disability Index to quantify pain and disability, respectively. Secondary outcome data included operative time, blood loss, and modified Mcnab criteria. Results At the end of the follow-up period, the rate of successful outcome of the endoscopic group was 87.2 and 77.8% for the control group after initial improvement by 87% at 3-month follow-up. The incidence of complications was 13% in both groups. Conclusion For DLSS, the endoscopic ULBD in experienced hands would have a better outcome than the microscopic ULBD regarding the postoperative clinical outcome and patient satisfaction.

Endoscopic Fenestration in Management of Monosegmental Degenerative Lumbar Spinal Canal Stenosis: A Clinical Cohort Study

Background Data: Minimally invasive fenestration has evolved recently to become the modern standard surgical solution for degenerative lumbar spinal canal stenosis (DLCS).Purpose: To investigate the safety and the efficacy of the endoscopic fenestration for patients with monosegmental degenerative lumbar spinal canal stenosis.Study Design: Prospective clinical cohort study.Patients and Methods: Thirty-five consecutive patients with DLCS were treated with endoscopic fenestration. Patients were treated with METRx system (Medtronic Sofamor Danek, Inc., Memphis, TN, USA), at Orthopedic Department, Zagazig University, between May 2012 and June 2015. Primary outcomes parameters included Numerical Rating Scale (NRS) for back and leg symptoms and Oswestry Disability Index (ODI) to quantify pain and disability, respectively. Secondary outcomes parameters included operative time, blood loss, preoperative and 3-month postoperative lumbar dynamic radiographs, and modified McNab criteria. Only patients who completed 36 months of follow-up were included in the final analysis of this study. Follow-up data were obtained from outpatient clinic follow-up visits by two independent physicians.Results: At the final follow-up, the improvement in claudicant leg pain and disability was statistically significant, and the endoscopic fenestration procedure did not affect the stability of the motion segment. The total success rate according to McNab criteria was 85.7% (30/35), fair 5.7% (2/35), and poor 8.6% (3/35). The mean NRS leg score significantly decreased from 7.3±1.5 preoperatively to 0.8±0.67 (P=0.001) postoperatively. The mean ODI score significantly decreased from 72.34±4.6 % preoperatively to 13.71±3.46 % postoperatively. There were no reported serious complications in any of our patients’ study.Conclusion: Endoscopic fenestration is a safe and effective technique in patients with degenerative lumbar stenosis. It allows adequate decompression of the neural elements and preserves spinal stability. (2018ESJ145)

Impact of Spinal Manipulation on Lower Extremity Motor Control in Lumbar Spinal Stenosis Patients: A Small-Scale Assessor-Blind Randomized Clinical Trial

ObjectiveThe purpose of this study was to quantify the impact of a single lumbar spinal manipulation (SM) intervention on the leg movement performance of degenerative lumbar spinal stenosis (LSS) patients in a small-scale registered randomized clinical trial. MethodsParticipants with LSS (n = 14) were tested at baseline for pain, lumbar range of motion, and behavioral or kinematic motor performance (using an established Fitts’ Law foot-pointing task), then underwent covariate adaptive randomization to receive SM or no intervention. Postintervention all dependent measures were repeated. Experimenters were blinded to patient group allocation. University ethics board approval was attained. ResultsFor the primary outcome movement time, there was no significant difference between groups. As predicted by Fitts’ Law, all participants had longer movement times as task difficulty increased. Secondary kinematic outcomes yielded no significant between-group differences. Consistent with Fitts’ Law, kinematic measures changed significantly with task difficulty. Pairwise comparisons revealed the kinematic variables were more adversely affected by greater movement amplitudes than target size changes. No exploratory differences in pain or lumbar range of motion were observed. ConclusionChanges in motor performance were not observed in this chronic pain population after a single SM intervention compared with a control group. Given the sample size, the study may have been underpowered to detect meaningful differences. Fitts’ Law was observed for the lower extremity–pointing task for an LSS population and may provide an objective measure of motor performance.

Clinical and MRI evaluation of degenerative lumbar spine stenosis

Clinical and MRI evaluation of degenerative lumbar spine stenosis

Patient’s Perception for Developing Research Questions of a Clinical Practice Guideline of Korean Medicine for Degenerative Lumbar Spinal Stenosis: A Descriptive Cross-Sectional Survey

Patient’s Perception for Developing Research Questions of a Clinical Practice Guideline of Korean Medicine for Degenerative Lumbar Spinal Stenosis: A Descriptive Cross-Sectional Survey

Lumbar Schmorl's Nodes and Their Correlation with Spine Configuration and Degeneration.

The aim of this study was to reveal whether demographic aspect, vertebral morphometry, and spine degeneration are associated with lumbar Schmorl's nodes (SNs). A retrospective cross-sectional study was performed using data from the Department of Radiology (Carmel, Medical Center, Israel) for 180 individuals: age range between 40 and 99 years; 90 males and 90 females. All participants had undergone high-resolution CT scans for abdominal diagnostic purposes in the same supine position prior to our study, which enabled the processing of the scans in all planes and allowed a 3D reconstruction of the lower lumbar region. Eighty individuals (44.4%) had at least one SN along the lumbar spine, particularly at L3-4 level (30%). Vertebral body length (L1 to L3) and width (L1 and L4) were significantly greater in the SNs group compared to non-SNs group. On contrast, disc height (L3-4 and L4-5) was significantly lesser in SNs group than non-SNs group. SNs was significantly associated with smoking (X2= 4.436, P=0.02) and degenerative lumbar spinal stenosis (X2= 5.197, P=0.038). Moreover, the prevalence of SN was significantly greater in individuals with vacuum phenomenon and osteophytes formation (L1-2 to L4-5 levels). This study indicates that vacuum phenomenon on L3-4 (OR: 4.7, P=0.034), smoking habit (OR: 3.2, P=0.003), disc height loss of L4-5 (OR: 0.798, P=0.008), vertebral body length of L1 (OR: 1.37, P<0.001), and age (OR: 1.05, P=0.002) increase the probability of developing lumbar SNs.

Is there a Correlation Between Degree of Radiologic Lumbar Spinal Stenosis and its Clinical Manifestation?

This was an observational cross-sectional study. The purpose of this study was to evaluate whether the degree of stenosis on magnetic resonance imaging (MRI) relates to the severity of clinical symptoms, disability, or neurological deficit in patients with symptomatic central lumbar spinal stenosis (LSS). The relationship between radiologic findings and the clinical manifestations of LSS remains unclear. A total of 84 patients (42 men, median age 70 y) with neurogenic claudication and central degenerative LSS were included in the study. The MRI parameters describing severity (anteroposterior diameter of dural sac, cross-sectional area of the dural sac, stenosis ratio, and Schizas qualitative morphologic classification were evaluated at maximum stenotic level) and the extent of stenosis (the number of central stenotic levels) were correlated to symptoms (pain intensity, walking capacity), functional disability (measured in terms of the Oswestry Disability Index), and neurological signs of LSS (neurological status was evaluated and scored by Neurological Impairment Score in LSS). A statistically significant correlation emerged only between the Neurological Impairment Score in LSS and Schizas morphologic classification (P=0.006). Pain intensity, walking capacity, and functional disability displayed no correlation with the MRI parameters of LSS. LSS is a clinicoradiologic syndrome with complex relationships between degree of radiologic stenosis disclosed by MRI and clinical manifestations. Neurological impairment in the lower extremities reflects the degree of morphologic LSS on MRI. This study did not identify any association between the degree of stenosis and functional disability, pain intensity, or walking capacity. Level II.

Patient's Perception for Developing Research Questions of a Clinical Practice Guideline of Korean Medicine for Degenerative Lumbar Spinal Stenosis: A Descriptive Cross-Sectional Survey

The purpose of this study is to explore patients’ perceptions that deserve attention when designing core questions for a clinical practice guideline of Korean medicine(KM) for degenerative lumbar spinal stenosis (LSS).

Combination of degenerative lumbar spinal stenosis and spinal deformity. Literature review

The study objective is to analyze currently available publications on spinal deformity in patients with degenerative lumbar spinal stenosis.Materials and methods. We analyzed 90 manuscripts published between 1980 and 2017.Results. We describe the parameters used to assess spinal deformity and evaluate their role for predicting the course of degenerative spinal disease. We provide the results of latest studies assessing the impact of spinal deformity on the outcome of surgical treatment in patients with degenerative lumbar spinal stenosis. We identified the following risk factors for scoliosis progression: wedge-shaped intervertebral disc in the frontal projection, low middle sacral axis, lateral spondylolisthesis, small L vertebral body, vertebral rotation, Cobb angle &gt;20°, and sagittal imbalance.Conclusion. We recommend decompressive interventions with facet joint preservation in patients with spinal deformity and degenerative lumbar spinal stenosis with no risk factors for scoliosis progression and radicular symptoms only (without pronounced low back pain). In patients with no risk factors for scoliosis progression, radicular symptoms, and low back pain, it is advisable to combine decompression with short fixation. For individuals at risk of scoliosis progression, we recommend supplementing decompression with long fixation exceeding scoliosis curve.

Influence of comorbidities on patients reported outcomes in degenerative lumbar spinal stenosis

IntroductionIn degenerative lumbar spinal stenosis (DLSS) variability of symptoms according to the severity of stenosis is not well understood. Therefore, another factor that impacts functional outcomes of DLSS patients has been evoked: patient's comorbidities. The aim of this study was to investigate influence of comorbidities on clinical symptoms and functional outcomes in DLSS patients. MethodsIn this prospective study, patients treated for DLSS were included during 12 consecutive months. Both clinical and radiographic exams were required to confirm DLSS diagnosis. Epidemiologic, clinical and radiographic data were collected. Two questionnaires were used to assess functional outcomes: a specific score dedicated to lumbar stenosis consequences assessment (self-administered Beaujon questionnaire, SABQ) and a non-specific score (Short Form 36, SF-36). Four comorbidity scores were calculated: Cumulative Illness Rating Scale, Charlson index, Functional Comorbidity Index and Index of Co-Existent Diseases Correlations between functional and comorbidity scores were calculated. Results250 patients were included (65.6±12 years). The four comorbidities scores were significantly correlated to total SABQ, as well as lumbar and radicular ischemia components. Best correlations were observed for cumulative illness rating scale and SABQ. Two factors were observed that significantly influenced the relationship between SABQ and cumulative illness rating scale: herniated disc and SF-36 general health perception. DiscussionThis study highlighted that preoperative function is influenced by comorbidities in DLSS patients. Relationships existed between comorbidities and symptoms related to low back pain and neurogenic claudication, contrary to radicular pain. Therefore, comorbidities might impact the variability of patients’ outcomes. This finding should be part of the patient's preoperative information. Moreover, role of comorbidities on postoperative outcomes need to be investigated.

Increased risk of symptomatic progression of instability following decompression for lumbar canal stenosis in patients receiving chronic glucocorticoids therapy

BackgroundLumbar decompression surgery is a commonly used treatment for degenerative lumbar spinal stenosis; however, some patients develop symptomatic spinal instability following decompression surgery. The objective of this study was to reveal risk factors for delayed instability following decompression surgery for lumbar spinal stenosis. MethodsOne hundred ten patients who underwent single-level lumbar decompression between 2008 and 2014 were retrospectively reviewed. Surgical indication for decompression surgery was symptomatic lumbar canal stenosis without spondylolisthesis or with minimum spondylolisthesis (less than 4 mm translation). Patients with gross segmental motion (>10° in disc angle, >2 mm translation) on flexion-extension lumbar radiographs were excluded. Age, sex, body mass index, smoking history, diabetes mellitus, autoimmune connective tissue diseases including rheumatoid arthritis, and the use of glucocorticoids were investigated. Radiographic measurements included disc angle, disc height, slippage, facet angle, segmental motion (flexion-extension), lumbar alignment, facet effusion, and disc degeneration. Data were analyzed using multivariate forward selection stepwise logistic regression, chi-square tests, and Student t-test. ResultsSix of 110 patients (5.5%) developed symptomatic spinal instability at the operative level and underwent spinal fusion surgery at an average of 2.1 years postoperatively. Autoimmune connective tissue disorders and chronic use of glucocorticoids were associated with the occurrence of symptomatic spinal instability requiring spine fusion surgery, while there was no significant difference in radiographic parameters and demographic factors excluding autoimmune connective tissue diseases between reoperation and non-reoperation groups. ConclusionsPatients with autoimmune connective tissue disorders receiving chronic glucocorticoid therapy are more likely to develop symptomatic spinal instability following decompression surgery for lumbar canal stenosis without or with minimal spondylolisthesis.

PEEK versus Silicon Interspinous Spacer for Reduction of Supradjacent Segment Degeneration following Decompression and Short-Segment Instrumentation for Degenerative Lumbar Spinal Stenosis.

Purpose A retrospective study that aims to report Adjacent Segment Degeneration (ASD) incidence and spinopelvic balance in short lumbosacral instrumentation for degenerative lumbar spinal stenosis. Although ASD is a common complication following lumbar fusion, the effect of an interspinous spacer (IS) in the supradjacent segment in short lumbosacral instrumented fusion and its interaction with spinopelvic balance has not been studied adequately. Methods From 55 consecutive age-, diagnosis-, and gender-matched patients aged 60±11 years, 17 (Group R) received PEEK IS; 18 (Group S) received Silicon IS compared with 20 controls (Group C) without receiving any IS. The functional outcome was evaluated with VAS and ODI. Spinopelvic balance was evaluated using SVA, T12-S1 LL, SS, PT, PI, and supradjacent segment disc heights. All spines were preoperatively balanced (SVA<40 mm). Results The follow-up averaged out to 56±11 months. VAS and ODI scores improved postoperatively in all 3 groups. SS and anterior disc height in the supradjacent free segment increased postoperatively compensatory to spinal alterations. Although 6, 4, and 5 patients from Groups R, S, and C, respectively, showed radiological progression of the preoperative degeneration grade in the supradjacent disc, only 2, 1, and 2 patients in Groups R, S, and C, respectively, developed symptomatic ASD in the 1st supradjacent segment solely. No additional surgery was required in any patient. Conclusion ASD incidence in the supradjacent segment following short lumbar fusion did not statistically significantly differ between PEEK and Silicon IS. There was a trend towards lower ASD incidence in Silicon IS. IS reduced ASD in both 1st and 2nd supradjacent segments. The authors speculate that soft stabilization provided by IS may be more advantageous for preventing ASD. This trial is registered with ClinicalTrials.govNCT03477955.

Wednesday, September 26, 2018 1:00 PM – 2:00 PM What's New in MIS: 40. Clinical and radiological outcomes of unilateral biportal endoscopic decompression by 30° endoscopy in lumbar spinal stenosis: minimum 2-years follow-up

BACKGROUND CONTEXT Open laminectomy or open laminectomy and lumbar spinal fusion has been regarded as the standard surgical method to date in degenerative spinal stenosis. The conventional method has been associated with complications such as paraspinal muscle damage, bleeding and infection. Several surgical techniques including microendoscopic decompression have been introduced to solve these problems. PURPOSE The aim of this study is to introduce a new spinal surgical technique using a 30° endoscopy through unilateral biportal endoscopic decompression technique and to report the results of patients who have been on follow-up for more than 2 years. STUDY DESIGN/SETTING Retrospective study. PATIENT SAMPLE Fifty-five patients who were suffering from neurologic symptoms by degenerative lumbar spinal stenosis were included even after preoperative conservative treatment. Patients with foraminal stenosis requiring an extraforaminal approach were excluded from the study. OUTCOME MEASURES Clinical outcomes were analyzed in view of modified-Macnab criteria, Oswestry Disability Index (ODI), Visual Analog Scale (VAS), and postoperative complications were analyzed. Plain X-ray studies before and after surgery were compared to confirm disc height reduction and progression of spondylolithesis. METHODS Two or three portals were used for each level. One portal was used for viewing, the others, for working of certain instruments. Unilateral laminotomy was followed by bilateral decompression under 30° endoscopy. RESULTS Eighty-one percent of the patients improved over a level based on the Macnab criteria. There were not any case of infection. The interverbral angle was significantly reduced from 6.26±3.54° to 5.58±3.23° at 2 years postoperatively, the dynamic intervertebral angle was slightly decreased by 6.54±3.71° at 6.76±3.59°, but was not statistically significant. No significant change in percentage slip was observed (3.76±5.01% preoperatively vs. 3.81±5.28% at the last follow-up). The dynamic percentage slip (gap in percentage slip between flexion and extension X-ray exams) did not change significantly from 2.65±3.37 to 2.76±3.71%. However, at 2 years postoperatively, intervertebral distance was significantly reduced from 10.43±2.23 mm to 10.0±2.24 mm. CONCLUSIONS Full endoscopic decompression using 30° endoscopy demonstrated a satisfactory clinical outcome after surgery. This technique was able to reduce infection, and was a good procedure without postoperative segmental instability. It could be alternative method of microscopic decompression. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

Wednesday, September 26, 2018 7:35 AM–9:00 AM ePosters: P132. Preexisting lumbar spinal stenosis does not affect outcomes of lumbar microdiscectomy

BACKGROUND CONTEXT Despite how commonly lumbar spinal stenosis is encountered, it is unknown if preexisting degenerative or congenital lumbar spinal stenosis has implications in patients who develop lumbar herniated nucleus pulposus (HNP) requiring discectomy. PURPOSE The purpose of the present study was to compare lumbar microdiscectomy patients with and without concomitant lumbar spinal stenosis in terms of baseline characteristics and longer term clinical outcome measures. STUDY DESIGN/SETTING Retrospective cohort series. PATIENT SAMPLE We performed a retrospective cohort analysis of patients who underwent a primary lumbar discectomy between 2009 and 2015 by one of two senior orthopedic spine surgeons. Patients were excluded from analysis if they had any previous lumbar surgery, were under 18years of age at the time of surgery, or had postoperative follow up less than 3 months. OUTCOME MEASURES Patient reported outcomes were obtained in the form of Oswestry Disability Index (ODI) scores, Visual Analog Scales (VAS) scores for the back and leg, 12-Item Short Form Mental and Physical Survey (SF-12) scores, and the Veterans Rand 12-Item Health Mental and Physical Survey (VR-12) scores. Patients were also surveyed about their expectations and satisfactions following surgery. METHODS Microdiscectomy patients with and without concomitant lumbar spinal stenosis were compared using chi-squared analysis and independent sample t-tests for categorical and continuous data, respectively. Bivariate and multivariate regressions were subsequently used to compare clinical outcomes between procedure groups. Multivariate analyses controlled for differences in baseline patient characteristics. RESULTS Overall, 134 consecutive patients who fulfilled our inclusion criteria were assessed. Average follow-up was 13.3±15.5 months (range 3–61 months). There were 49 patients (36.6% of all patients) with concomitant stenosis. Patients with concomitant stenosis were older (57.4+14.2vs. 42.5+14.1, p CONCLUSIONS Patients with concomitant lumbar stenosis who underwent lumbar microdiscectomy for HNP had similar clinical outcomes compared to patients with isolated HNP. Reoperation rates are similar between the two groups of patients. Both groups report being satisfied with their outcome with their expectations being met or exceeded.

Wednesday, September 26, 2018 10:35 AM – 12:00 PM Understanding Lumbar Stenosis/Spondylolisthesis: 13. Unilateral laminotomy for bilateral decompression versus decompression with instrumented fusion for lumbar degenerative spondylolisthesis at five-year follow-up

BACKGROUND CONTEXT Controversy exists regarding whether fusion should be used to augment decompression surgery in patients with symptomatic lumbar spinal stenosis with grade I/II (low-grade), stable degenerative spondylolisthesis. For years, the standard has been fusion with laminectomy in order to prevent postoperative instability. However, instability and reoperations may be reduced or prevented using less invasive, structure sparing decompression techniques without the need for fusion. PURPOSE To compare reoperation rates within a 5-year follow-up period of unilateral laminotomy for bilateral decompression (ULBD) versus posterior lumbar decompression with instrumented fusion (fusion) for patients with degenerative spondylolisthesis with spinal stenosis in a multicenter database. STUDY DESIGN/SETTING Retrospective cohort study. PATIENT SAMPLE A final cohort of 601 Kaiser Permanente Northern California members with diagnoses of lumbar degenerative spondylolisthesis and lumbar spinal stenosis of whom 164 patients underwent ULBD and 437 underwent fusion between January 2007 and December 2011. OUTCOME MEASURES The primary outcome measure was reoperation rate at 5-year postoperative follow-up. Secondary outcome measures included blood loss during surgery, length of stay, reoperation type, reoperation level, and 90-day postoperative complication rates. METHODS We identified 164 patients with lumbar degenerative spondylolisthesis and lumbar stenosis who underwent ULBD between January 2007 and December 2011. These patients were propensity score matched on age at surgery, gender, race and smoking status with patients who underwent fusion (n=437). The primary outcome was 5-year reoperation rate and secondary outcome measures included postoperative complication rates, reoperation type, reoperation level, blood loss during surgery, and length of stay. RESULTS The reoperation rate within 5-year follow-up was significantly lower at 10.4% in the ULBD group compared to 17.2% in the fusion group (p=.0393). Type of reoperation was similar between the two groups. Reoperation at the index or adjacent level was not significant different between the two groups. Patients that underwent ULBD had significantly less mean estimated blood loss compared to fusion (82 vs. 445 ml, p CONCLUSIONS For patients with stable degenerative spondylolisthesis and lumbar stenosis, ULBD is a viable, durable option compared to fusion with a lower reoperation rate within a 5-year follow-up period, as well as decreased blood loss and length of stay. Further prospective studies are required to determine the optimal clinical scenario for ULBD in the setting of degenerative spondylolisthesis. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs

Wednesday, September 26, 2018 7:35 AM–9:00 AM ePosters

BACKGROUND CONTEXT Degenerative lumbar spinal stenosis is a common condition, predominantly affecting middle-aged and elderly people. This study focused on patients with neurogenic claudication secondary to lumbar stenosis without deformity or spondylolisthesis. PURPOSE We sought to determine whether the addition of fusion to decompression resulted in improved clinical outcomes at 3 and 12 months postsurgery. METHODS We conducted a multicentre, ambispective review of consecutive spine surgery patients enrolled in the Canadian Spine Outcomes and Research Network (CSORN) between October 2012 and January 2015. Data from the six sites with the highest volume of neurogenic claudication patients were used (n=937). The sample was categorized into two groups: (1) those that had decompression alone, and (2) those that underwent decompression plus fusion. RESULTS The decompression plus fusion group had significantly more operative time, blood loss and length of hospital stay (p CONCLUSIONS The addition of fusion to decompression did not result in improved outcomes at either 3 or 12 month follow-up. This is the first study specific to the Canadian population comparing decompression alone to decompression plus fusion in those with neurogenic claudication.

Assessing the real benefits of surgery for degenerative lumbar spinal stenosis without instability and spondylolisthesis: a single surgeon experience with a mean 8-year follow-up

BackgroundThe degenerative lumbar spinal stenosis is one of the most commonly treated spinal disorders in older adults; despite its increasing frequency, it is not yet clear what the most effective therapy might be. The aim of this study is to investigate the very long term results of a homogenized cohort of patients suffering from lumbar spinal stenosis: the first subset of patients operated on with laminectomy and the second subset of patients was also advised to undergo laminectomy but never operated on.MethodsPatients from both subgroups were advised to undergo surgery, according to the same criteria, in the period between 2000 and 2010 and were re-evaluated in the period between January and December 2016.ResultsComparing the two subsets of patients, both suffering from clinically relevant LSS, the first subset returns a statistically significant clinical improvement at follow-up. The rate of excellent results decreases over years. Iatrogenic spinal instability incidence was found to be 3.8% in the present cohort.ConclusionsAlthough the improvement of the first postoperative years decreases over time and despite the lack of general consensus, the lack of established shared guidelines and the limitations of this research, the results support the utilisation of surgery for the management of this condition.Level of Evidence3.

The pelvic radius technique in the assessment of spinopelvic sagittal alignment of degenerative spondylolisthesis and lumbar spinal stenosis

BackgroundDegenerative spondylolisthesis (DS) and lumbar spinal stenosis (LSS) are the most common degenerative spinal diseases. The evaluating of spinopelvic sagittal alignment of the two diseases using pelvic radius (PR) technique have not been reported. The purpose of this study was to use PR measurement technique to compare the differences in spinopelvic sagittal alignment between DS and LSS. MethodsA total of 145 patients with DS or LSS were retrospectively reviewed. Seventy patients with DS (DS group) and 75 age-matched patients with LSS (LSS group) were enrolled. Spinopelvic parameters including pelvic angle (PA), regional lumbopelvic lordosis (PR–L1, PR–L2, PR–L3, PR–L4 and PR–L5), total lumbopelvic lordosis (PR–T12), pelvic morphology (PR–S1), sagittal vertical axis from the C7 plumb line (SVA), lumbar lordosis (LL), thoracic kyphosis (TK), L4 slope and L5 slope were assessed in the two groups. Several parameters of DS and LSS group were compared with the normal population (NP). ResultsThe PR–L4, PR–L5 and PR-S1 in the DS group were significantly smaller than those in the LSS group. There was no difference in PR–T12 between the DS group and NP (p > 0.05), while PR–T12 of the LSS group were significantly lower (p < 0.01). Degree of correlations among spinopelvic parameters differed between the two groups. PR–T12 of the DS group was more strongly correlated with PA (r = −0.829, p < 0.001) than with LL (r = 0.664, p < 0.001), TK (r = 0.582, p < 0.001). PR-T12 of the LSS group was more strongly correlated with LL (r = 0.854, p < 0.001), TK (r = 0.616, p < 0.001) than with PA (r = −0.582, p < 0.001). ConclusionsPR–L4 and PR–L5 may be the predisposing factors for DS development. Spinopelvic morphology differed in patients with DS and LSS compared to NP. The compensatory mechanisms to maintain spinopelvic sagittal alignment in DS and LSS patients may be different.