Degenerative Lumbar Spinal Stenosis Research Articles

Risk Factors for Adverse Events and Reintervention after Surgery for Lumbar Spine Stenosis. A 10-Year Experience of Clinical Practice in a Third Level Hospital from Bogotá, Colombia

Introduction Degenerative lumbar spinal stenosis is present in patients around 50 to 60 years old. It is the most common spinal surgical indication in patients over 65 years old. The aim of this study was to determine the risk factors associated with adverse events and reintervention after surgery for degenerative lumbar spinal stenosis, based on a 10-year retrospective analysis of clinical records in a third level hospital in Bogotá, Colombia. Material and Methods An analytical prevalence study was developed through 429 clinical records of patients who underwent surgery for degenerative lumbar spinal stenosis. Results 429 clinical records were reviewed. 55% were female; the mean age was 55 years +/−16,5. The average follow up was 33,8 months. Adverse events were present in 17,2% of patients. Dural lesion was the most frequent complication (9.8%). Multivariate analysis showed a relation between complications and BMI (OR 1,8; p = 0,029), duration of symptoms (OR 1,08; p = 0,047), length of stay (OR 1,67; p = 0,023) and multi level surgery (OR: 2.99; p = 0,015). 4.7% of patients required early reintervention after surgery and 16,1% required it during follow-up. The most common late reintervention cause was re-stenosis of the same segment (7%). Adjacent segment disease was present in 6,1% of patients. Conclusion BMI, duration of symptoms, length of stay and multi level surgery were identified as risk factors for adverse events and reintervention after surgery for degenerative lumbar spinal stenosis. Mitigation of these risk factors before surgery for degenerative lumbar spinal stenosis, may decrease the proportion of complications and reinterventions in our institutions.

Histopathological Features of Facet Osteoarthritis in Patients with Lumbar Spinal Stenosis

Introduction Lumbar spinal stenosis (LSS) is a degenerative, age-related narrowing of the lower spinal canal that causes pressure on the nerves, leading to pain and reduced mobility. Hypertrophy of ligament flava and facet joints combined with disc protrusions are a causative for LSS. Osteoarthritic changes to the facet joint, including joint space narrowing, subchondral cysts and osteophyte formation are commonly detected using magnetic resonance imaging (MRI) and computed tomography (CT) scanning. However, the pathomechanisms of facet joint osteoarthritis (OA) at a cellular and molecular level are poorly understood and have been scarcely studied. In this study we sought to investigate the histological features and to uncover cellular pathomechanisms of facet joint OA. Material and Methods Fifteen patients undergoing surgical decompression due to degenerative LSS were included in this study (9 female/6 male, median age 66, range 49–85). Routine preoperative X-ray and MRI scanning of the lumbar spine was performed in all subjects. Severity of facet joint OA was assessed in MRI images using the Weishaupt grading system for the lumbar spine. The medial portion of facet joints was collected during surgical decompression of the spinal canal and processed for tissue histology. Tissue morphology was evaluated using haematoxylin and eosin (HE), Safranin-O and van Gieson's stains. The presence of macrophages, blood vessels and nerve fibers was investigated using immunohistological staining for their respective markers CD68, CD34 and PGP9.5. Functional osteoclasts were visualized using tartrate-resistant acid phosphatase (TRAP) staining. Subchondral bone area fraction (B.Ar/T.Ar) was determined using the ImageJ-plugin BoneJ. Results OA was evident in MRI images characterized by joint space narrowing, bone edema and cysts and hypertrophy of articular processes. The severe OA phenotype in facet joints from LSS patients was confirmed at a histological level by complete loss of proteoglycan staining, CD34+ vessel penetration, and fissuring of cartilage tissue. Subchondral B.Ar/T.Ar ranged between 0.6 and 0.8. In all samples, subchondral marrow spaces contained CD34+ blood vessels and CD68+ mononuclear macrophages. CD68+ multinucleated osteoclasts were detected in resorption pits at the bone surface in 80 percent of the patients. Functionality of osteoclasts was confirmed by positive staining of multinucleated bone cells for TRAP in serial sections. Osteoblast activity was demonstrated in 60 percent of the patients and predominantly characterized by large areas of intramembranous bone formation near the osteochondral junction. Formation of an osteoclast-rich pannus-like tissue was seen in one sample. Innervation of subchondral marrow spaces by PGP9.5-positive nerve fibers was scarce and exclusively found in the vicinity of arterioles. Conclusion Facet joints in LSS patients display radiological and histopathological features of OA. Two major OA phenotypes can be distinguished based upon cellular pathomechanisms in subchondral bone tissue: 1) osteoblast-rich intramembranous bone formation and 2) osteoclast/macrophage rich remodeling. Osteoimmunological mechanisms, specifically the interaction of CD68+ macrophages with bone-resident cells, play a – previously unknown – role in regulating subchondral bone sclerosis in progressive osteoarthritis. Targeting osteoimmunology might hold potential as a disease-modifying treatment for osteoarthritis.

Comparative study of the efficacy of limaprost and pregabalin as single agents and in combination for the treatment of lumbar spinal stenosis: a prospective, double-blind, randomized controlled non-inferiority trial

Background ContextAlthough the simultaneous management of neuronal ischemia-related pain and compression-demyelination–related neuropathic pain is considered optimal in treating lumbar spinal stenosis (LSS), the effect of combination therapy with pregabalin and limaprost has not been elucidated. PurposeThis study aimed to compare the effects of limaprost and pregabalin individually and in combination for the treatment of LSS. Study DesignThis is a prospective, double-blind, double-dummy, randomized controlled trial. Patient SampleThe sample consists of patients with LSS. Outcome MeasuresThe baseline-adjusted Oswestry Disability Index (ODI) score, visual analog scale (VAS) scores for leg pain, the European Quality of Life-5 dimensions (EQ-5D), and initial claudication distance (ICD). MethodsThe present study (ClinicalTrials.gov, number NCT01888536) was a prospective, double-blind, double-dummy, randomized controlled trial designed to determine the efficacy of limaprost in alleviating leg pain, improving disability, and increasing walking distance in persons with degenerative LSS in three different treatment groups: limaprost alone, pregabalin alone, and combined limaprost and pregabalin through 1:1:1 allocation. The primary outcome was the baseline-adjusted ODI score at 8 weeks after treatment. The non-inferior margin of the ODI was set at δ=10 points. ResultsThe baseline-adjusted ODI score (primary outcome) at 8 weeks after treatment in the limaprost group was not inferior to those in the pregabalin and limaprost+pregabalin groups. The overall changes of the baseline-adjusted ODI scores, VAS scores for leg pain, the EQ-5D, and ICD during the follow-up assessments over an 8-week period (secondary end point) were not different among the three groups. The baseline-adjusted ODI scores and VAS scores for leg pain decreasedsignificantly over time after treatment in all three groups. The baseline-adjusted EQ-5D score and ICD also increased significantly over time after treatment in all three groups. ConclusionsThe efficacy of limaprost for lumbar spinal stenosis was not inferior compared with that of pregabalin or the combination of limaprost and pregabalin in terms of disability. Therefore, combined treatment with limaprost and pregabalin does not provide additional relief in symptoms in patients with LSS compared with monotherapy with limaprost or pregabalin.

Risk factor analysis for postoperative urinary retention after surgery for degenerative lumbar spinal stenosis

Background ContextPostoperative urinary retention (POUR) may not be considered a major complication after surgery for degenerative lumbar spinal stenosis. However, improper management of transient POUR leads to bladder overdistension and permanent bladder detrusor damage. Systematic monitoring of POUR may be recommended in vulnerable patients. PurposeThe aim of the present study was to determine the incidence of and risk factors for POUR. Study Design/SettingThis is a retrospective nested case-control study. Patient SampleA total of 284 consecutive patients (M : F=125:159; mean age, 63.3 years) who underwent spine surgery for degenerative lumbar spinal stenosis were reviewed. Outcome MeasuresA multivariable logistic model was utilized to identify risk factors. MethodsA systematic postoperative voiding care protocol was applied for all patients to monitor them for the development of POUR. An indwelling urethral catheter was inserted intraoperatively and removed in the postanesthesia care unit. The patients were encouraged to void within 6 hours postoperatively and every 4–6 hours thereafter. After each voiding, the postvoid residual urine (PVR) was measured by an ultrasound bladder scan. POUR was defined as the inability to void or having a PVR≥100 mL for more than 2 days after surgery. ResultsThe incidence of POUR was 27.1% (77/284). Older age (odds ratio, 1.062; 95% confidence interval, 1.029–1.095) and a long duration of surgery (odds ratio, 1.003; 95% confidence interval, 1.001–1.005) were significant risk factors. A formula for determining the probability of POUR was developed, and a probability of ≥0.26 was regarded as the cut-off value (sensitivity of 0.75 and specificity of 0.57; C-statics, 0.684). ConclusionPOUR was a common morbidity after surgery for degenerative lumbar spinal stenosis. We recommend adopting a systematic postoperative voiding care protocol to prevent bladder overdistension and detrusor damage, especially for elderly patients and those who have undergone longer surgeries.

Degenerative lumbar spinal stenosis treatment with Aperius™ PerCLID™ system and Falena® interspinous spacers: 1-year follow-up of clinical outcome and quality of life.

Evaluation of the efficacy of the Falena(®) and Aperius™ PerCLID™ interspinous devices in the treatment of degenerative lumbar spinal stenosis with neurogenic intermittent claudication refractory to conservative treatment. We retrospectively analyzed data from 24 patients (20 male and 4 female patients; 61 ± 7 years old), treated with an implantation of the AperiusTM PerCLID™ system, and from 35 patients (29 male and 6 female patients; 65 ± 9 years old) treated with the Falena(®) interspinous device.Patient pain intensity was evaluated by a 10-point visual analog scale (VAS), with a score (ranging from 0 = no pain to 10 = unbearable pain) that was collected before the procedure, at baseline; and at months 1, 6 and 12 after the interventional procedure. The assessment of quality of life (QOL) impairment was evaluated by the Oswestry Disability Index (ODI) questionnaire, which was administered beforehand at baseline; and at months 1, 6 and 12 after the interventional procedure. The vertebral canal area was measured by magnetic resonance imaging (MRI) scans before the treatment and at the one-year follow-up. All patients completed the study with no complications. Both the Falena group and Aperius group of surgery patients showed a statistically significant reduction of their VAS and ODI scores at the 6- and 12-month follow-up (p < 0.0001). A statistically significant increase in the vertebral canal area was observed both in the group that received Falena (p < 0.0001) and in the group that received Aperius (p = 0.0003). At the 1-year follow-up, we observed that there was a higher increase of vertebral canal area in those patients whom were treated with the Falena device (p < 0.001). The implantation of Falena(®) and Aperius™ PerCLID™ interspinous devices is an effective and safe procedure, in the medium term.

The Impact of Obesity on the Outcome of Decompression Surgery in Degenerative Lumbar Spinal Canal Stenosis: Analysis of the Lumbar Spinal Outcome Study (LSOS): A Swiss Prospective Multicenter Cohort Study.

Prospective, multicenter cohort study including 8 medical centers of the Cantons Zurich, Lucerne, and Thurgau, Switzerland. The aim of the study was to assess whether obese patients benefit after decompression surgery for degenerative lumbar spinal stenosis (DLSS). Lumbar decompression surgery has been shown to improve quality of life in patients with DLSS. In the existing literature, the efficacy of lumbar decompression in the obese population remains controversial. Baseline patient characteristics and outcomes were analyzed at 6 and 12 months follow-up with the Spinal Stenosis Measure (SSM), the Numeric Rating Scale (NRS), Feeling Thermometer (FT), the EQ-5D-EL, and the Roland and Morris Disability Questionnaire (RMDQ). Body mass index (BMI) was classified into 3 categories according to the WHO. Minimal clinically important differences (MCIDs) in SSM for different BMI categories were considered as main outcome. Of the 656 patients in the Lumbar Spinal Outcome Study database as of end of October 2014, 166 patients met the inclusion criteria. Fifty (30.1%) had a BMI less than 25 (underweight and normal weight group), 72 (43.4%) had a BMI between 25 and less than 30 (preobesity group), and 44 (26.5%) patients had a BMI at least 30 (obese group). We found for the main outcome that in obese patients 36% reached MCID at 6 months, and 48% at 12 months. The estimated odds ratios for MCID in the obese group were 0.78 (0.34-1.82) at 6 months and 0.99 (0.44-2.23) at 12 months in a logistic regression model adjusting for levels of laminectomy. In the additional outcomes, SSM, NRS, FT, and RMDQ showed statistically significant mean improvements in the 6 and 12 months follow-up. Obese patients can expect clinical improvement after lumbar decompression for DLSS, but the percentage of patients with a meaningful improvement is lower than in the group of patients with underweight, normal weight, and preobese weight at 6 and 12 months.

Microscopic decompression for lumbar spinal canal stenosis

Study designA retrospective review and prospective follow-up were performed of 106 patients who had undergone microscopic decompressive surgery without fusion in the year 2006 at Munich Spine Center, Germany.ObjectiveThis study aimed to determine the 4–5-year outcome of microscopic unilateral laminotomy for bilateral decompression in degenerative lumbar spinal stenosis and to detect the possible predictors of the surgical outcome.Summary of background dataThere is limited information on the impact of surgery for lumbar spinal stenosis on symptoms, functional status, and satisfaction, as well as reoperation.Patients and methodsPatients were considered eligible for the study if they had clinical and radiographic evidence of degenerative lumbar spinal stenosis, including patients with degenerative spondylolisthesis type 1 according to Myerding and patients with degenerative scoliosis. All patients underwent microscopic decompressive surgery without fusion in the year 2006 at the Munich Spine Center, Germany. One hundred and six patients were available for follow-up during the year 2010.ResultsAt 4–5 years after the operation, 76 (71.7%) patients were satisfied with the surgical outcome. The overall complication rate was 12.2%. 23 (21%) patients required a second operative procedure, whereas three (2.8%) patients required a third operative procedure after the index operation. Two of the 23 patients who had second operations had presumed instability and underwent fusion.ConclusionUnilateral laminotomy for bilateral decompression is an adequate microsurgical technique for decompression of lumbar spinal stenosis that minimizes operative invasiveness and tissue trauma while maximizing preservation of the spinal integrity and stability. Secondary postoperative instability is avoided and excellent long-term clinical outcome could be expected.

"Slalom": Microsurgical Cross-Over Decompression for Multilevel Degenerative Lumbar Stenosis.

Objective. Selective, bilateral multisegmental microsurgical decompression of lumbar spinal canal stenosis through separate, alternating cross-over approaches. Indications. Two-segmental and multisegmental degenerative central and lateral lumbar spinal stenosis. Contraindications. None. Surgical Technique. Minimally invasive, muscle, and facet joint-sparing bilateral decompression of the lumbar spinal canal through 2 or more alternating microsurgical cross-over approaches from one side. Results. From December 2010 until December 2015 we operated on 202 patients with 2 or multisegmental stenosis (115 f; 87 m; average age 69.3 yrs, range 51–91 yrs). All patients were suffering from symptoms typical of a degenerative lumbar spinal stenosis. All patients complained about back pain; however the leg symptoms were dominant in all cases. Per decompressed segment, the average OR time was 36 min and the blood loss 45.7 cc. Patients were mobilized 6 hrs postop and hospitalization averaged 5.9 days. A total of 116/202 patients did not need submuscular drainage. 27/202 patients suffered from a complication (13.4%). Dural tears occurred in 3.5%, an epidural hematoma in 5.5%, a deep wound infection in 1.98%, and a temporary radiculopathy postop in 1.5%. Postop follow-up ranged from 12 to 24 months. There was a significant improvement of EQ 5 D, Oswestry Disability Index (ODI), VAS for Back and Leg Pain, and preoperative standing times and walking distances.

Analysis of dynamic implants use in surgical treatment of degenerative lumbar spine stenosis

To improve the results of surgical treatment of lumbar spine stenosis. Surgical treatment of 84 patients was analyzed. There were 2 groups consisting of 48 and 36 patients respectively. Advanced decompression and fusion were performed in group 1, minimally invasive decompression (flavectomy, marginal arch resection, facetectomy) with implantstion of interspinous dynamic implants DIAM -- in group 2. Patients with isthmic spondylolisthesis were excluded. Both methods did not show difference in efficacy of leg pain relief during follow-up (1.7--8.5 years). 16.7% of patients after fusion of more than 2 segments had pain above and below fusion area in long-term postoperative period. Such pain was not observed in group 2. One patient of the 1st group had fixation system destruction that required repeated intervention. Groups have not difference in back pain severity after surgery on 1 segment. Also less intraoperative blood loss and duration of surgery were established in group 2. Minimally invasive decompression with implantstion of interspinous dynamic implants is effective and safe alternative to advanced decompression and fusion in lumbar spine stenosis management.

Predictors of Reoperation after Microdecompression in Lumbar Spinal Stenosis.

ObjectiveThe risk factors of reoperation after microdecompression (MD) for lumbar spinal stenosis (LSS) are unclear. In this study, we presented the outcomes of MD for degenerative LSS and investigated the risk factors associated with reoperation.MethodsA retrospective review was conducted using the clinical records and radiographs of patients with LSS who underwent MD. For clinical evaluation, we used the Japanese Orthopedic Association (JOA) scoring system for low back pain, body mass index, and Charlson comorbidity index. For radiological evaluation, disc height, facet angle, and sagittal rotation angle were measured in operated segments. Also the Modic change and Pfirrmann grade for degeneration in the endplate and disc were scored.ResultsForty-three patients aged 69±9 years at index surgery were followed for 48±25 months. The average preoperative JOA score was 6.9±1.6 points. The score improved to 9.1±2.1 points at the latest follow-up (p<0.001). Seven patients (16.3%) underwent reoperation. Clinical and radiological factors except operation level and Pfirrmann grade showed a p-value >0.1. Patients with Pfirrmann grade IV and lower lumbar segment had a 29.1% rate of reoperation (p=0.001), whereas patients without these factors had a 0% rate of reoperation.ConclusionModerate disk degeneration (Pfirrmann IV) in lower lumbar segments is a risk factor of disk herniation or foraminal stenosis requiring reoperation after MD in LSS.

Tratamiento quirúrgico del canal lumbar estrecho degenerativo. Serie de casos

BackgroundThe primary objective of the surgical treatment is to relieve patient's symptoms, reduce the disability, correct deformities, stabilize the column, diminish the fixed segments, protect neurological organs and decrease rehabilitation time in patients where conservative treatment had failed. The aim of the study is to compare the percentage of functional limitation and pain intensity in the presurgical and postsurgical period in patients with lumbar spinal stenosis with surgical treatment with decompressive laminectomy, transpedicular instrumentation and arthrodesis. MethodsDescriptive, comparative longitudinal study of 30 records of patients with clinical and imagenological diagnosis, where the Oswestry Disability Index and Visual Analogue Scale were applied in the pre and three-months postsurgical treatment. ResultsThe most of the patients had canal defects in two or more levels (69.9%), mainly between L4-L5. Needed instrumentation of two or more levels (79.9%). There were intrasurgical complications in three of the patients (13.3%), all were dural tears; it was only one case of fistula as postsurgical complication (3,3%). About postsurgical results, it was observed a median difference of Visual Analog Scale between presurgical and postsurgical of 5.1 points, and the difference in the median and standard deviation in the pre and postsurgical Oswestry Disability Index of 33.3%. All of the patients submitted to surgical treatment by this technique had relevant postsurgical clinical relevance during a postsurgical following of 18,6±11,8 months. DiscussionThe decompressive laminectomy technique, transpedicular instrumentation and arthrodesis was effective to accomplish a clinical relevant benefit in patients with degenerative lumbar spinal stenosis. Evidence levelIV.

Is epidural steroid injection effective for degenerative lumbar spinal stenosis?

There are several nonsurgical alternatives to treat radicular pain in degenerative lumbar spinal stenosis. Epidural steroid injections have been used for several decades, but the different studies have shown variable effects. Searching in Epistemonikos database, which is maintained by screening 30 databases, we identified nine systematic reviews including seven pertinent randomized controlled trials. We concluded epidural steroid injection probably leads to little or no effect on reducing radicular pain of spinal stenosis.

The effects of aquatic walking and jogging program on physical function and fall efficacy in patients with degenerative lumbar spinal stenosis.

The purpose of this study was to evaluate the effects of 12-week aqua walking and jogging program on muscle function, ankle range of motion (ROM), balance and fell efficacy in degenerative lumbar spinal stenosis (DLSS) patients. Six patients (2 males, 4 females) with DLSS participated in aquatic exercise program 3 times per week with each session of 60 min (warming-up, aqua walking, aqua jogging and cool down) at 1 m 20 cm–1 m 30 cm deep pool. Janda’s muscle function test, ankle ROM, Berg balance scale (BBS) and fall efficacy scale (FES) were analyzed before and after the training intervention. We found significant increases in balance, muscle function, ankle ROM and fall efficacy after training intervention. In conclusion, aquatic exercise seems to affect physical function and fall efficacy positively in elderly DLSS patients.

Effects of a prehabilitation program on patients’ recovery following spinal stenosis surgery: study protocol for a randomized controlled trial

BackgroundDegenerative lumbar spinal stenosis is a prevalent condition in adults over the age of 65 and often leads to deconditioning. Although the benefits of surgery outweigh those of conservative approaches, physical rehabilitation may be used to improve function and to minimize the risk of persistent dysfunction. This study protocol was designed to establish the feasibility of a full-scale randomized controlled trial and to assess the efficacy of an active preoperative intervention program on the improvement of clinical parameters and functional physical capacity in patients undergoing surgery for lumbar spinal stenosis.Methods/DesignForty patients will be recruited and randomly allocated to one of the 2 treatment arms: 6 weeks supervised preoperative rehabilitation program (experimental group) or hospital standard preoperative management (control group). The intervention group will be trained three times per week, with each session aiming to improve strength, muscular endurance, spinal stabilization and cardiovascular fitness. Intensity and complexity of exercises will be gradually increased throughout the sessions, depending on each participant’s individual progress. Primary outcomes are level of low back disability and level of pain. Secondary outcomes include the use of pain medication, quality of life, patient’s global impression of change, lumbar extensor muscles endurance, maximum voluntary contraction of lumbar flexor and extensor muscles, maximum voluntary contraction of knee extensors, active lumbar ranges of motion, walking abilities, and cardiovascular capacity. Both the primary and secondary outcomes will be measured at baseline, at the end of the training program (6 weeks after baseline evaluation for control participants), and at 6 weeks, 3 and 6 months postoperatively.DiscussionThis study will inform the design of a future large-scale trial. Improvements of physical performances before undergoing lumbar surgery may limit functional limitations occurring after a surgical intervention. Results of this study will provide opportunity to efficiently improve spinal care and advance our knowledge of favorable preoperative strategies to optimize postoperative recovery.Trial registrationUS National Institutes of Health Clinical Trials registry NCT02258672, 10 February 2014.

Fitts’s Law using lower extremity movement: Performance driven outcomes for degenerative lumbar spinal stenosis

A paucity of objective outcome measures exists for assessing movement disorders, including degenerative lumbar spinal stenosis (LSS). Fitts’s Law provides a novel approach to clinical outcome measurement since performance is resistant to learning, and task difficulty can be altered. The objective of the present study was to compare, using a Fitts’s task, movement performance of individuals with and without LSS to determine if motor difficulties that arise with LSS impede the planning, initiation, or execution of deliberate lower limb movements. Twelve pre-surgical LSS patients and twelve control participants from the community performed a Fitts’s Law (foot reaching) task, while LSS participants also completed pain and disability questionnaires. Fitts’s Law was evident for both groups, however the LSS group’s movements were more adversely impacted as task difficulty increased. Specifically, the LSS group’s movement time and time to peak velocity (ttPV) increased as task index of difficulty increased, while peak velocity decreased. Correlations between ttPV and leg pain, and with stenosis impairment severity respectively, provided evidence that less support leg pain and less stenosis impairment severity yield faster ttPV in the moving leg at the highest index of difficulty. Therefore a lower extremity Fitts’s Law task captured differences in the planning and execution of leg movements between healthy and LSS populations.

Management of Degenerative Lumbar Spinal Stenosis in the Elderly.

Lumbar spinal stenosis can cause symptomatic neurogenic claudication alongside radicular pain and weakness. In appropriately selected patients, surgical intervention has been demonstrated to provide for improvement in pain, disability, and quality of life. This systematic review sought to define the utility and safety of such decompression with or without arthrodesis in the management of symptomatic lumbar spinal stenosis for elderly patients older than 65 years of age. A systematic review was conducted using MEDLINE for literature published through December 2014. The first question focused on the effectiveness of lumbar spinal surgery for symptomatic lumbar spinal stenosis in elderly patients (over age 65 y). The second question focused on safety of surgical intervention on this elderly population with emphasis on perioperative complication rates. Review of 11 studies reveals that the majority of elderly patients exhibit significant symptomatic improvement, with overall benefits observed for pain (change visual analog scale 4.4 points) and disability (change Oswestry Disability Index 23 points). Review of 11 studies reveals that perioperative complications were infrequent and acceptable with pooled estimates of mortality (0.5%), inadvertent durotomy (5%), and wound infection (2%). Outcomes seem less favorable with greater complication rates among patients with diabetes or obesity. Based on largely low-quality, retrospective evidence, we recommend that elderly patients should not be excluded from surgical intervention for symptomatic lumbar spinal stenosis.

Superion(®) InterSpinous Spacer for treatment of moderate degenerative lumbar spinal stenosis: durable three-year results of a randomized controlled trial.

PurposeThis report provides the 3-year clinical outcomes from the randomized, controlled US Food and Drug Administration Investigational Device Exemption trial of the Superion® for the treatment of moderate degenerative lumbar spinal stenosis.Patients and methodsThe Superion® was evaluated in the treatment of subjects aged 45 years or older suffering from symptoms of intermittent neurogenic claudication, secondary to a confirmed diagnosis of moderate degenerative lumbar spinal stenosis at one or two contiguous levels from L1 to L5. Patients were treated between June 2008 and December 2011 at 31 investigational sites. Three hundred ninety-one subjects were included in the randomized study group consisting of 190 Superion® and 201 X-STOP® control subjects. The primary composite endpoint was individual patient success based on four components: improvement in two of three domains of the Zurich Claudication Questionnaire, no reoperations at the index level, no major implant/procedure-related complications, and no clinically significant confounding treatments.ResultsAt 3 years, the proportion of subjects achieving the primary composite endpoint was greater for Superion® (63/120, 52.5%) than for X-STOP® (49/129, 38.0%) (P=0.023) and the corresponding success rates exceeded 80% for each of the individual components of the primary endpoint in the Superion® group (range: 81%–91%). Improvements in back and leg pain severity as well as back- and disease-specific functional outcomes were also maintained through 36 months.ConclusionThe 3-year outcomes from this randomized controlled trial demonstrate durable clinical improvement consistently across all clinical outcomes for the Superion® in the treatment of patients with moderate degenerative lumbar spinal stenosis.

The Impact of Obesity on the Outcome of Decompression Surgery in Degenerative Lumbar Spinal Canal Stenosis: A Swiss Prospective Cohort Multicenter Study

Aims: To examine whether obese patients benefit after decompression surgery for degenerative lumbar spinal canal stenosis (DLSS). Lumbar decompression surgery has been shown to improve quality of life in lumbar spinal canal stenosis. However, in the obese population this remains a matter of debate in the existing literature. This is a prospective, multicenter cohort study in the metropolitan area of Zurich, Switzerland. Methods: Baseline patient characteristics and outcomes were analyzed at 6- and 12-month follow-up with the Spinal Stenosis Measure (SSM), the Numeric Rating Scale (NRS), Feeling Thermometer (FT), the EQ-5D-EL, and the Roland and Morris Disability Scale (RMDS). Body mass index (BMI) was classified into three categories according to WHO. Odds ratios for meaningful clinical important difference (MCIDs) in SSM were estimated for different BMI categories. Results: Of the 656 patients in the LSOS database as of end of October 2014, 186 patients met the inclusion criteria. Fifty-seven had a BMI < 25 (underweight and normal-weight group), 78 had a BMI between 25 and 29.9 (preobesity group), and 51 patients had a BMI ≥ 30 (obese group). We found for the primary outcome that in obese patients 35% reached MCID in SSM at 6 months and 45% at 12 months. The estimated odds ratios for MCID in the obese group were 0.68 (0.31–1.49) at 6 months and 0.84 (0.39–1.79) at 12 months in a logistic regression model adjusting for levels of laminectomy. In the secondary outcome, SSM, NRS, FT, and RMDQ showed statistically significant mean improvements in the 6- and 12-month follow-up. Conclusions: Obese patients can expect clinical improvement after lumbar decompression for symptomatic DLSS, but the percentage of patients with MCID is lower than in the group of patients with underweight, normal, and preobese weight at 6 and 12 months.

Aperius interspinous device for degenerative lumbar spinal stenosis: a review.

With an aging population, degenerative lumbar spinal stenosis (DLSS) leading to neurogenic intermittent claudication (NIC) is a growing problem. For patients suffering from this condition, interspinous process distraction devices (IPDs) offer an effective and cheap alternative to conservative or decompressive surgery. Aperius is one such device that has been gaining popularity for its percutaneous insertion under local anesthetic, short operative time, and low risk of complications. The main objective of this review was to carry out a comprehensive search of the literature to evaluate the effectiveness and potential complications of Aperius. A database search, including PubMed, Clinical trials.gov, Cochrane (CENTRAL), MEDLINE, CINAHL, EMBASE, and Scopus, was carried out to identify relevant articles written in English reporting on complications with a minimum 12-month follow-up. The literature search resulted in six eligible studies; two nonrandomized comparative and four prospective case series were available. The analysis revealed that in total, 433 patients underwent treatment with Aperius, with all studies demonstrating an improvement in outcome measures. The average follow-up was 17 months with an overall complication rate of 10.62%. Overall, the quality of evidence is low, suggesting that currently, the evidence is not compelling and further prospective randomized trials including cost-effectiveness studies are required.

Bilateral versus unilateral interlaminar approach for bilateral decompression in patients with single-level degenerative lumbar spinal stenosis: a multicenter retrospective study of 175 patients on postoperative pain, functional disability, and patient satisfaction.

The bilateral and unilateral interlaminar techniques for bilateral decompression both demonstrate good results for the treatment of degenerative lumbar spinal stenosis (DLSS). Although there is some discussion about which approach is more effective, studies that directly compare these two popular techniques are rare. To address this shortcoming, this study compares postoperative functional disability, pain, and patient satisfaction among patients with single-level DLSS who underwent bilateral decompression using either a bilateral or unilateral approach. This retrospective study included patients who underwent operations between November 1, 2009, and October 1, 2011. These patients underwent single-level bilateral decompressive surgery using either the bilateral or unilateral interlaminar approach at one of 5 participating hospitals. Exclusion criteria included previous lumbar surgery, additional disc surgery, and spondylolisthesis requiring fusion surgery. Primary outcome measures included bodily pain (as reported using the visual analog scale [VAS]), the Roland-Morris Disability Questionnaire (RMDQ), and the Oswestry Disability Index (ODI). In addition, reductions in leg and back symptoms and the patient's general evaluation of the procedure were queried. Finally, patient satisfaction and surgical parameters were evaluated. Questionnaires were sent to each patient's home, and electronic patient files were used to collect the data. One hundred and seventy-five patients returned the questionnaire (74.4% response rate; 68 and 107 patients who underwent the bilateral or unilateral approach, respectively). Mean age at surgery was 68 years (range 34-89 years), and the mean follow-up period was 14.2 months (range 3.3-27.4 years). There were no significant differences in ODI (20.3 vs 22.6 for the bilateral and unilateral approaches, respectively), RMDQ (3.99 vs 4.8, respectively), or pain scores between treatment groups. Back symptoms were reduced in 74.8% (bilateral: 74.6% vs unilateral: 75%; not significant), and leg symptoms in 80.6% of the patients (bilateral: 73.1% vs unilateral: 85.4%; p = 0.048). In total, 72.1% (bilateral) and 80.0% (unilateral) of patients reported good overall treatment results (p = 0.226). Significantly more patients in the unilateral group reported a better overall satisfaction with the procedure (82.1% vs 69.1%; p = 0.047). There were no differences in postoperative functional disability and pain between the surgical techniques. The significant differences in patient satisfaction and reduction in leg symptoms were unrelated to surgical technique. The overall treatment results were satisfactory. Both techniques are safe and effective options for treating patients with single-level DLSS.