Central Lumbar Spinal Stenosis Research Articles

Decompression alone or decompression with fusion for lumbar spinal stenosis: five-year clinical results from a randomized clinical trial

Decompression alone or decompression with fusion for lumbar spinal stenosis: five-year clinical results from a randomized clinical trial

Early Clinical and Radiologic Evaluation of Unilateral Biportal Endoscopic Unilateral Laminotomy and Bilateral Decompression in Degenerative Lumbar Spinal Stenosis: A Retrospective Study.

The aim of this study is to evaluate the changes in radiologic parameters and clinical outcomes following unilateral biportal endoscopic unilateral laminotomy and bilateral decompression (UBE ULBD) for treatment of central lumbar spinal stenosis. Forty-one central lumbar spinal stenosis patients who underwent UBE ULBD were enrolled from April 2021 to February 2023. Visual analog scale (VAS) for back pain and leg pain, Oswestry Disability Index (ODI) score, and the modified MacNab criteria were assessed preoperatively and postoperatively. The preoperative and postoperative cross-sectional area of the spinal canal (CSAC), anteroposterior diameter, horizontal width, and ipsilateral and contralateral lateral recess height were calculated from axial computed tomography (CT) scans. Percentage of facet joint preservation measured on axial CT scans was obtained preoperation and postoperation. The VAS for back and leg pain improved from 7.24 ± 0.80 and 7.59 ± 0.59 preoperatively to 2.41 ± 0.55 and 2.37 ± 0.62 (p < 0.05) postoperatively and 1.37 ± 0.54 and 1.51 ± 0.55 at the last follow-up (p < 0.05). For ODI, improvement from 60.37 ± 4.44 preoperatively to 18.90 ± 4.66 (p < 0.05) at the last follow-up was observed. CT scans demonstrated that the postoperative CSAC increased significantly from 287.84 ± 87.81 to 232.97 ± 88.42 mm (p < 0.05). The mean postoperative anteroposterior diameter and horizontal width increased significantly from 18.01 ± 3.13 and 19.57 ± 3.80 to 22.19 ± 4.56 and 21.04 ± 3.72 mm, respectively (p < 0.05). The ipsilateral lateral recess height and contralateral lateral recess height were 3.39 ± 1.12 and 3.20 ± 1.14 mm preoperatively and 4.03 ± 1.37 and 3.83 ± 1.32 mm (p < 0.05) postoperatively, with significant differences. The ipsilateral and contralateral facet joint preservations were 88.17 and 93.18%, respectively. The UBE ULBD surgery is a safe and effective treatment for central lumbar spinal stenosis, associated with significant improvement in clinical outcomes and radiologic parameters. Studies with larger samples and longer follow-up periods are needed for further research.

Dural Sac Cross-sectional area change from preoperatively and up to 2 years after decompressive surgery for central lumbar spinal stenosis: investigation of operated levels, data from the NORDSTEN study.

The aim of the present study was to investigate how canal area size changed from before surgery and up to 2 years after decompressive lumbar surgery lumbar spinal stenosis. Further, to investigate if an area change postoperatively (between 3 months to 2 years) was associated with any preoperative demographic, clinical or MRI variables or surgical method used. The present study is analysis of data from the NORDSTEN- SST trial where 437 patients were randomized to one of three mini-invasive surgical methods for lumbar spinal stenosis. The patients underwent MRI examination of the lumbar spine before surgery, and 3 and 24 months after surgery. For all operated segments the dural sac cross-sectional area (DSCA) was measured in mm2. Baseline factors collected included age, gender, BMI and smoking habits. Furthermore, surgical method, index level, number of levels operated, all levels operated on and baseline Schizas grade were also included in the analysis. 437 patients were enrolled in the NORDSTEN-SST trial, whereof 310 (71%) had MRI at 3 months and 2 years. Mean DSCA at index level was 52.0mm2 (SD 21.2) at baseline, at 3 months it increased to 117.2mm2 (SD 43.0) and after 2 years the area was 127.7mm2 (SD 52.5). Surgical method, level operated on or Schizas did not influence change in DSCA from 3 to 24 months follow-up. The spinal canal area after lumbar decompressive surgery for lumbar spinal stenosis increased from baseline to 3 months after surgery and remained thereafter unchanged 2 years postoperatively.

Clinical Outcomes Following Decompression of Central Canal and Lateral Recess Simultaneous Stenosis, with a Focus on Multilevel Stenosis: A Randomized Comparison of Microscopic Bilateral Laminotomy versus Total Laminectomy with Posterior Spinal Fusion

In patients with simultaneous lumbar central spinal stenosis (LCSS) and lateral recess stenosis (LRS) at multiple levels, spinal decompression using microscopic bilateral laminotomy was compared to total laminectomy plus medial facetectomy and fusion (LF). From 2017 to 2022, this trial was performed to examine 96 patients with concomitant LCS and LRS at multilevel. Of the 96 patients, 48 were allocated to the following groups: LF (group I) or microscopic bilateral laminotomy (group II). However, 76 patients completed the study. We compared the outcomes in these 2 groups. Microscopic bilateral laminotomy was superior in most outcome measures. Delta-visual analog scale leg pain in group II was significantly greater than in group I (mean-group I: 4.368 vs. group II: 5.368, P value=0.001). Complication and revision rates were lower in the microscopic bilateral laminotomy than in group I, except for incidental durotomy occurrence (group II: 31.58% -group I: 7.89%, P value=0.0190). The rate of revision surgery for group I compared with group II was 44.74% versus 13.16% (P value=0.0047), indicating the superiority of laminotomy over LF. The mean length of hospital stay was 3.551±0.6349 in group II versus 6.774±1.197 in group I (P value <0.0001). Also, blood loss during surgery was significantly lower in group II (P value <0.0001). The findings indicate that microscopic bilateral laminotomy provides favorable clinical and radiological outcomes for individuals experiencing multilevel lumbar central canal and LRS. However, a higher frequency of durotomy may occur during microsurgical procedures.

Redundant nerve roots on magnetic resonance imaging can predict ongoing denervation in patients with lumbar spinal stenosis.

Redundant nerve roots (RNRs) are abnormally elongated and tortuous nerve roots that develop secondary to degenerative spinal stenosis. RNRs have been associated with poorer clinical outcomes after decompression surgery; however, studies on their clinical characteristics are limited. This study aimed to investigate the association between RNRs and denervation potentials, that is, abnormal spontaneous activity (ASA), on electromyography. We retrospectively reviewed data of patients who underwent an electrodiagnostic study of the lower extremities between January 2020 and March 2023. Of these, patients with lumbar central spinal stenosis, as seen on magnetic resonance imaging, were included. We analyzed clinical and imaging data, including presence of ASA, and compared them according to the presence of RNRs. Multivariable logistic regression analysis was employed to identify factors associated with development of ASA. Among the 2003 patients screened, 193 were included in the study. RNRs were associated with advanced age (p < .001), longer symptom duration (p = .009), smaller cross-sectional area of the dural sac at the stenotic level (p < .001), and higher frequency of ASA (p < .001). Higher probability of ASA was correlated with greater RNR severity (p < .001). In the multivariable logistic regression analysis, ASA occurrence was associated with smaller cross-sectional area, multiple stenotic sites, and severe-grade RNRs. The presence of RNRs, particularly severe-grade RNRs, was identified as a significant risk factor for the development of ASA on electromyography. This finding may aid physicians in estimating the prognosis of patients with central spinal stenosis.

Recovery pattern after decompression of central lumbar spinal stenosis: a prospective observational cohort study

BackgroundDetailed preoperative information is associated with superior outcomes. We aimed to describe the recovery pattern after decompression of central lumbar spinal stenosis (CLSS).Methods50 patients aged 51–85 years who underwent decompression without fusion due to CLSS were followed from before to after surgery (post-op day 1, 7, and 14). Back and leg pain were evaluated using the Numeric Rating Scale (NRS; 0 = no pain 0, 10 = worst pain) and quality of life using the EuroQol-5D index (0 = death, 1 = best), and EQ-5D-visual analogue scale (VAS; 0 = worst, 100 = best).ResultsNRS leg pain was reduced from preoperative to first postoperative day by 5.2 (6.1, 4.3) (mean (95%CI)], and NRS back pain from postoperative day 1–7 by 0.6 (1.2, 0.03) and from day 7 to 14 by 0.7 (1.3, 0.2)]. In contrast, EQ-5D index increased from preoperative to first postoperative day by 0.09 (0.06, 0.13) and from day 1 to 7 by 0.05 (0.02,0.08), and EQ-5D VAS from preoperative to first postoperative day by 13.7 (9.1, 18.3) and from day 1 to 7 by 6.0 (2.0, 10.0). After two weeks, 51% of the patients had improved above the minimal clinically important difference (MCID) in back pain and 71% in leg pain.ConclusionsPatients scheduled for decompression due to CLSS should be informed that improvement in leg pain and quality of life in general can be expected within one day of surgery, that quality of life improves a little further in the first postoperative week, and that back pain improves in the first 2 postoperative weeks. In most patients, decompression without fusion due to CLSS seems to achieve clinically relevant improvement within 2 weeks.

Get Back, a person-centred digital programme targeting physical activity for patients undergoing spinal stenosis surgery—a study protocol of a randomized feasibility study

BackgroundSpinal stenosis is the most common reason for elective spine surgery, and the cardinal symptom is leg pain and discomfort when walking. Patients with spinal stenosis have a decreased level of physical activity and thereby an increased risk of poor health. Get Back is a person-centred digital programme that strives to support patients being physically active after surgery. The aim is to explore if Get Back, in its present format (referred to as Get Backfeasibility), is feasible and contributes to detectable change in variables related to intervention content.MethodsThirty patients planned for decompression surgery due to central lumbar spinal stenosis who present with low physical activity, pain catastrophizing or fear of movement, will be included in a randomized feasibility study. All patients will be randomly allocated to either Get Backfeasibility or usual physical therapy. Get Backfeasibility aims to increase the patient’s physical activity level by combining a person-centred and cognitive behavioural approach. It comprises 10 video and telephone sessions led by a physical therapist over 12 weeks (pre/postoperatively). Outcomes are treatment fidelity (treatment dose, adherence, and content), process feasibility (recruitment, intervention use, and acceptability of measurements and intervention), and variables related to the intervention content (steps per day, physical activity level, pain catastrophizing, fear of movement, and general self-efficacy). Treatment fidelity and feasibility data will be assessed during the full study period (12 weeks). Physical activity, physical capacity, and patient-reported outcomes will be assessed digitally at baseline (2 weeks preoperatively) and 11–12 weeks postoperatively. Variables related to the intervention content will be monitored weekly through a digital application. Feasibility data will be analysed descriptively and inferentially using a nonparametric approach, data from repeated measures will be displayed graphically and data from telephone interviews will be analysed using content analysis with a descriptive manifest approach.DiscussionThe results will provide information on whether Get Back in its present format is feasible and can be evaluated for effectiveness in a larger randomized controlled trial, for patients with a low physical activity level and a high fear of movement who are undergoing decompression surgery.Trial registrationRegistered at ClinicalTrails.gov 04/08/2023, registration no. NCT05806593.

Multi-pose-based convolutional neural network model for diagnosis of patients with central lumbar spinal stenosis.

Although the role of plain radiographs in diagnosing lumbar spinal stenosis (LSS) has declined in importance since the advent of magnetic resonance imaging (MRI), diagnostic ability of plain radiographs has improved dramatically when combined with deep learning. Previously, we developed a convolutional neural network (CNN) model using a radiograph for diagnosing LSS. In this study, we aimed to improve and generalize the performance of CNN models and overcome the limitation of the single-pose-based CNN (SP-CNN) model using multi-pose radiographs. Individuals with severe or no LSS, confirmed using MRI, were enrolled. Lateral radiographs of patients in three postures were collected. We developed a multi-pose-based CNN (MP-CNN) model using the encoders of the three SP-CNN model (extension, flexion, and neutral postures). We compared the validation results of the MP-CNN model using four algorithms pretrained with ImageNet. The MP-CNN model underwent additional internal and external validations to measure generalization performance. The ResNet50-based MP-CNN model achieved the largest area under the receiver operating characteristic curve (AUROC) of 91.4% (95% confidence interval [CI] 90.9-91.8%) for internal validation. The AUROC of the MP-CNN model were 91.3% (95% CI 90.7-91.9%) and 79.5% (95% CI 78.2-80.8%) for the extra-internal and external validation, respectively. The MP-CNNbased heatmap offered a logical decision-making direction through optimized visualization. This model holds potential as a screening tool for LSS diagnosis, offering an explainable rationale for its prediction.

Comparison of ligamentum flavum thickness between central and lateral lesions in a patient with central lumbar spinal canal stenosis.

Thickened ligamentum flavum has been considered as a major cause of central lumbar spinal canal stenosis (CLSCS). Previous studies have demonstrated that ligamentum flavum thickness (LFT) is correlated with aging, degenerative spinal stenosis, and disc degeneration. Thus, hypertrophy of the ligamentum flavum is a major cause of CLSCS, and measurement of LFT has been considered a morphologic parameter in the diagnosis of CLSCS. To our knowledge, comparison of LFT between central and lateral lesions has not been reported. In addition, no research has analyzed best clinical cutoff values of central ligament flavum thickness (CLFT) and lateral ligament flavum thickness (LLFT). This study aimed to compare CLFT with LLFT in patients with CLSCS and further compare the CLFT and LLFT findings between the 2 groups to analyze LFT variation. Both CLFT and LLFT samples were collected from 101 participants with CLSCS and from 103 participants in the control group who underwent lumbar magnetic resonance imaging without evidence of CLSCS. Axial T2-weighted lumbar magnetic resonance scans were acquired at the L4 to 5 facet joint level from each participant. Average CLFT value was 2.25 ± 0.51 mm in the control group and 4.02 ± 0.74 mm in the CLSCS group. Average LLFT value was 2.50 ± 0.51 mm in the control group and 3.38 ± 0.66 mm in the CLSCS group. CLSCS patients had significantly higher CLFT and LLFT (both P < .001). Regarding the validity of both CLFT and LLFT as predictors of CLSCS, a receiver operating characteristic estimation revealed that the most suitable cutoff value for CLFT was 3.10 mm, with sensitivity of 95.0%, specificity of 94.2%, and an area under the curve of 0.97. The best cut-off value of LLFT was 2.92 mm, with sensitivity of 78.2%, specificity of 77.7%, and area under the curve of 0.87. We have 4 important new findings: The mean CLFT is significantly lower than that of the mean LLFT in the normal control group; CLFT and LLFT are both significantly associated with CLSCS; Increase rate of CLFT is faster than that of LLFT in the CLSCS group; and CLFT is a more sensitive measurement parameter to predict CLSCS than LLFT.

Is the presence of foraminal stenosis associated with outcome in lumbar spinal stenosis patients treated with posterior microsurgical decompression

BackgroundWe aim to investigate associations between preoperative radiological findings of lumbar foraminal stenosis with clinical outcomes after posterior microsurgical decompression in patients with predominantly central lumbar spinal stenosis (LSS).MethodsThe study was an additional analysis in the NORDSTEN Spinal Stenosis Trial. In total, 230 men and 207 women (mean age 66.8 (SD 8.3)) were included. All patients underwent an MRI including T1- and T2-weighted sequences. Grade of foraminal stenosis was dichotomized into none to moderate (0–1) and severe (2–3) category using Lee’s classification system. The Oswestry Disability Index (ODI), Zurich Claudication Questionnaire (ZCQ), and numeric rating scale (NRS) for back and leg pain were collected at baseline and at 2-year follow-up. Primary outcome was a reduction of 30% or more on the ODI score. Secondary outcomes included the mean improvement on the ODI, ZCQ, and NRS scores. We performed multivariable regression analyses with the radiological variates foraminal stenosis, Pfirrmann grade, Schizas score, dural sac cross-sectional area, and the possible plausible confounders: patients’ gender, age, smoking status, and BMI.ResultsThe cohort of 437 patients presented a high degree of degenerative changes at baseline. Of 414 patients with adequate imaging of potential foraminal stenosis, 402 were labeled in the none to moderate category and 12 in the severe category. Of the patients with none to moderate foraminal stenosis, 71% achieved at least 30% improvement in ODI. Among the patients with severe foraminal stenosis, 36% achieved at least 30% improvement in ODI. A significant association between severe foraminal stenosis and less chance of reaching the target of 30% improvement in the ODI score after surgery was detected: OR 0.22 (95% CI 0.06, 0.83), p=0.03. When investigating outcome as continuous variables, a similar association between severe foraminal stenosis and less improved ODI with a mean difference of 9.28 points (95%CI 0.47, 18.09; p=0.04) was found. Significant association between severe foraminal stenosis and less improved NRS pain in the lumbar region was also detected with a mean difference of 1.89 (95% CI 0.30, 3.49; p=0.02). No significant association was suggested between severe foraminal stenosis and ZCQ or NRS leg pain.ConclusionIn patients operated with posterior microsurgical decompression for LSS, a preoperative severe lumbar foraminal stenosis was associated with higher proportion of patients with less than 30% improvement in ODI.Trial registrationThe study is registered at ClinicalTrials.gov (22.11.2013) under the identifier NCT02007083.

Case-matched radiological and clinical outcome evaluation of interlaminar versus microsurgical decompression of lumbar spinal stenosis

PurposeEndoscopic spine surgery is a globally expanding technique advocated as less invasive for spinal stenosis treatment compared to the microsurgical approach. However, evidence on the efficiency of interlaminar full-endoscopic decompression (FED) vs. conventional microsurgical decompression (MSD) in patients with lumbar spinal stenosis is still scarce. We conducted a case-matched comparison for treatment success with consideration of clinical, laboratory, and radiologic predictors.MethodsWe included 88 consecutive patients (FED: 36/88, 40.9%; MSD: 52/88, 59.1%) presenting with lumbar central spinal stenosis. Surgery-related (operation time, complications, length of stay (LOS), American Society of Anesthesiologists physical status (ASA) score, C-reactive protein (CRP), white blood cell count, side of approach (unilateral/bilateral), patient-related outcome measures (PROMs) (Oswestry disability index (ODI), numeric rating scale of pain (NRS; leg-, back pain), EuroQol questionnaire (eQ-5D), core outcome measures index (COMI)), and radiological (dural sack cross-sectional area, Schizas score (SC), left and right lateral recess heights, and facet angles, respectively) parameters were extracted at different time points up to 1-year follow-up. The relationship of PROMs was analyzed using Spearman’s rank correlation. Surgery-related outcome parameters were correlated with patient-centered and radiological outcomes utilizing a regression model to determine predictors for propensity score matching.ResultsComplication (most often residual sensorimotor deficits and restenosis due to hematoma) rates were higher in the FED (33.3%) than MSD (13.5%) group (p < 0.05), while all complications in the FED group were observed within the first 20 FED patients. Operation time was higher in the FED, whereas LOS was higher in the MSD group. Age, SC, CRP revealed significant associations with PROMs. We did not observe significant differences in the endoscopic vs. microsurgical group in PROMs. The correlation between ODI and COMI was significantly high, and both were inversely correlated with eQ-5D, whereas the correlations of these PROMs with NRS findings were less pronounced.ConclusionsEndoscopic treatment of lumbar spinal stenosis was similarly successful as the conventional microsurgical approach. Although FED was associated with higher complication rates in our single-center study experience, the distribution of complications indicated surgical learning curves to be the main factor of these findings. Future long-term prospective studies considering the surgical learning curve are warranted for reliable comparisons of these techniques.

Relative risk factors of nerve root sedimentation sign (SedSign) in patients with severe central lumbar spinal stenosis (LSS)

The incidence of nerve root sedimentation sign (SedSign) was evaluated to explore potential pathogenesis in patients with severe lumbar spinal stenosis (LSS). In a total of 209 patients with severe LSS, 290 intervertebral levels were narrow, among which 248 showed a positive SedSign, giving a prevalence of 85.52%. Those levels with a positive SedSign were further analyzed relative to those with a negative SedSign. There was no significant difference between the two groups for the cross-sectional area (CSA) or the posteroanterior diameter (PAD). In contrast, there was a significant difference between the groups for the grade of degenerative facet joint (DFJ) (p < 0.05), the thickness of ligamentum flavum (TLF) (p < 0.01), and the cross-sectional area difference (CSAD) (p < 0.01). In addition, receiver operating characteristic (ROC) curves were used to identify associated factors. The area under the ROC curve for PAD was 0.608 (p < 0.05), for DFJ was 0.634 (p < 0.05), for TLF was 0.74 (p < 0.01), and for CSAD was 0.911 (p < 0.01). In summary, a positive SedSign has notable advantages in assisting with the diagnosis of severe LSS. Compression of the dural sac from the rear may be the main risk factors of a positive SedSign.

The Effectiveness of Facet Joint Injection with Steroid and Botulinum Toxin in Severe Lumbar Central Spinal Stenosis: A Randomized Controlled Trial.

Lumbar central spinal stenosis (LCSS) is a common disorder that causes disability and pain in the elderly. It causes pain in the radicular leg. Recently, transforaminal epidural steroid injection (TFESI) has been widely used to control radicular leg pain caused by LCSS. However, in cases of severe LCSS, drugs injected using TFESI cannot spread into the spinal canal and would have less therapeutic effects than in mild LCSS. To compensate for this limitation of TFESI, we injected steroids and botulinum toxin type A into the bilateral facet joints, evaluated their effects, and compared them with those of TFESI. One hundred patients with severe LCSS were included in the study and randomly allocated to either the facet injection (FI) or TFESI group. For 50 patients in the FI group, 30 mg (40 mg/mL) of triamcinolone with 50 IU of botulinum toxin type A mixed with a 1 mL solution of 100 mL of 50% dextrose water and 30 mL of 4% lidocaine were administered into the bilateral facet joints under fluoroscopy. For 50 patients in the TFESI group, 30 mg (40 mg/mL) of triamcinolone with 0.8 mL of 2% lidocaine and 2.5 mL of 50% dextrose water was injected bilaterally under fluoroscopy. Radicular leg pain (measured with a numeric rating scale) and pain-related disability (measured with the modified Oswestry Disability Index) due to severe LCSS were significantly reduced after facet joint injection. The therapeutic effects were greater after facet joint injection than after bilateral TFESI. The injection of a mixed solution of steroids and botulinum toxin type A into the bilateral facet joints would be a beneficial therapeutic option in patients with severe LCSS.

A comparison study on patient-reported outcome between obese and non-obese patients with central lumbar spinal stenosis undergoing surgical decompression: 14,984 patients in the National Swedish Quality Registry for Spine Surgery.

Obesity has been associated with inferior outcomes after laminectomy due to central lumbar spinal stenosis (CLSS); we evaluated whether this occurs in surgery on national bases. We retrieved pre- and 1-year postoperative data from the National Swedish Quality Registry for Spine Surgery regarding patients aged ≥ 50 with laminectomy due to CLSS in 2005-2018. 4,069 patients had normal weight, 7,044 were overweight, 3,377 had class I obesity, 577 class II obesity, and 94 class III obesity ("morbid obesity"). Patient-reported outcome included satisfaction after 1 year, leg pain (Numerical Rating Scale [NRS], rating 0-10), disability (Oswestry Disability Index [ODI], rating 0-100). Complications were also retrieved. 1-year postoperatively, 69% of patient of normal weight, 67% who were overweight, and 62% with obesity (classes I-III aggregated) were satisfied (p < 0.001) and 62%, 60%, and 57% in obese groups I-III, respectively (p = 0.7). NRS leg pain improved in normal-weight patients by 3.5 (95% CI 3.4-3.6), overweight by 3.2 (CI 3.1-3.2), and obese by 2.6 (CI 2.5-2.7), and 2.8 (CI 2.7-2.9), 2.5 (CI 2.2-2.7), and 2.6 (CI 2.0-3.2) in obese classes I-III, respectively. ODI improved in normal weight by 19 (CI 19-20), overweight by 17 (CI 17-18), and obese by 14 (CI 13-15), and 16 (CI 15-17), 14 (CI 13-16), 14 (CI 11-18) in obese classes I-III, respectively. 8.1% of normal weight, 7.0% of overweight, and 8.1% of obese patients suffered complications (p = 0.04) and 8.1%, 7.0%, and 17% among obese classes I-III, respectively (p < 0.01). Most obese patients are satisfied after laminectomy due to CLSS, even if satisfaction rate is inferior compared with normal-weight patients. The morbidly obese have more complications than patients with lower BMI.

The prevalence of redundant nerve roots in standing positional MRI decreases by half in supine and almost to zero in flexed seated position: a retrospective cross-sectional cohort study

PurposeThis retrospective cross-sectional cohort study investigated the influence of posture on lordosis (LL), length of the spinal canal (LSC), anteroposterior diameter (APD L1-L5), dural cross-sectional area (DCSA) of the lumbar spinal canal, and the prevalence of redundant nerve roots (RNR) using positional magnetic resonance imaging (MRI) (0.6 T).MethodsSixty-eight patients with single-level degenerative central lumbar spinal stenosis (cLSS) presenting with RNR in the standing position (STA) were also investigated in supine (SUP) or neutral seated (SIT) and flexed seated (FLEX) positions. Additionally, 45 patients complaining of back pain and without MRI evidence of LSS were evaluated. Statistical significance was set at p < 0.05.ResultsControls (A) and patients with cLSS (B) were comparable in terms of mean age (p = 0.88) and sex (p = 0.22). The progressive transition from STA to FLEX led to a comparable decrease in LL (p = 0.97), an increase in LSC (p = 0.80), and an increase in APD L1-L5 (p = 0.78). The APD of the stenotic level increased disproportionally between the different postures, up to 67% in FLEX compared to 29% in adjacent non-stenotic levels (p < 0.001). Therefore, the prevalence of RNR decreased to 49, 26, and 4% in SUP, SIT, and FLEX, respectively.ConclusionThe prevalence of RNR in standing position was underestimated by half in supine position. Body postures modified LL, LSC, and APD similarly in patients and controls. Stenotic levels compensated for insufficient intraspinal volume with a disproportionate enlargement when switching from the STA to FLEX.

Clinical Application of Large Channel Endoscopic Systems with Full Endoscopic Visualization Technique in Lumbar Central Spinal Stenosis: A Retrospective Cohort Study.

Recently, large channel endoscopic systems and full endoscopic visualization technique have been used to perform unilateral laminotomy for bilateral decompression (ULBD) treatment for lumbar central spinal stenosis (LCSS). However, various endoscopic systems possess different design parameters, which may affect the technical points and treatment outcomes. The object of this retrospective study was to compare the efficiency, safety, and effectiveness of ULBD under the iLESSYS Delta system versus the Endo-Surgi Plus system. In the period from October 2020 to April 2021, ULBD was performed using the iLESSYS Delta system or Endo-Surgi Plus system to treat LCSS. Patients were classified into two groups based on the endoscopy system employed. Patient demographics, perioperative indexes, complications, and imaging characteristics were reviewed. Clinical outcomes were quantified using back and leg visual analog scale (VAS) scores and Oswestry Disability Index (ODI) at the time points of follow-up. Thirty-two patients were assigned to the iLESSYS Delta system group and 37 to the Endo-Surgi Plus system group. In the comparison between the two groups, the Endo-Surgi Plus system possessed a shorter incision length and operation time (p < 0.005), and no statistical differences in other aspects were observed. The dural sacs of both groups were significantly expanded postoperatively compared to preoperatively (p < 0.001). Both groups experienced improvements in VAS and ODI scores at all time points (p < 0.001) and equally low frequency of complications. Current research suggests that both the Endo-Surgi Plus system and iLESSYS Delta system achieved favorable high safety and clinical outcomes in ULBD for treatment of LCSS. The use of a fully visualized trephine may have increased the efficiency of the Endo-Surgi Plus system. Moreover, the Endo-Surgi Plus system may be associated with a wider decompression range and indications.

Diagnostic triage in patients with central lumbar spinal stenosis using a deep learning system of radiographs.

Magnetic resonance imaging (MRI) is the gold-standard tool for diagnosing lumbar spinal stenosis (LSS), but it is difficult to promptly examine all suspected cases with MRI considering the modality's high cost and limited accessibility. Although radiography is an efficient screening technique owing to its low cost, rapid operability, and wide availability, its diagnostic accuracy is relatively poor. In this study, the authors aimed to develop a deep learning model with a convolutional neural network (CNN) for diagnosing severe central LSS using radiography and to evaluate radiological diagnostic features using gradient-weighted class activation mapping (Grad-CAM). Patients who had undergone both spinal MRI and radiography in the period from May 1, 2005, to December 31, 2017, were screened. According to the formal MRI report, participants were consecutively included in the severe central LSS or healthy control group, and radiographs for both groups were collected. A CNN-based transfer learning algorithm was developed to classify radiographic findings as LSS or normal (binary classification). The proposed models were evaluated using six performance metrics: area under the receiver operating characteristic curve (AUROC), accuracy, sensitivity, specificity, and positive and negative predictive values. The VGG19 model achieved the highest accuracy with an AUROC of 90.0% (95% CI 89.8%-90.3%) by training 12,442 images. Accuracy was 82.8% (95% CI 82.5%-83.1%) by averaging 5-fold models. Feature points on Grad-CAM were reasonable, and the features could be categorized into reduced disc height, narrow foramina, short pedicle, and hyperdense facet joint. The AUROC in the extra validation was 89.3% (95% CI 88.7%-90.0%). Accuracy was 81.8% (95% CI 80.6%-83.0%) by averaging 5-fold models. Multivariate logistic regression analysis showed that a combination of demographic factors (age and sex) did not improve the model performance. The algorithm trained by a CNN to identify central LSS on radiographs showed high diagnostic accuracy and is expected to be useful as a triage tool. The algorithm could accurately localize the stenotic lesion to assist physicians in the identification of LSS.

Change in sagittal alignment after decompression alone in patients with lumbar spinal stenosis without significant deformity: a prospective cohort study.

The authors' objective was to investigate whether sagittal balance improves in patients with spinal stenosis after decompression alone. This prospective longitudinal cohort study compared preoperative and 6-month postoperative 36-inch full-length radiographs in patients aged older than 60 years. Patients underwent decompression alone for central lumbar spinal stenosis with either a minimally invasive bilateral laminotomy for central decompression, unilateral laminectomy as an over-the-top procedure for bilateral decompression, or traditional wide laminectomy with removal of the spinous processes on both sides. The following radiographic parameters were measured: sagittal vertical axis (SVA), lumbar lordosis (LL), pelvic tilt (PT), pelvic incidence (PI), PI-LL mismatch, coronal Cobb angle, and sacral slope (SS). Patient-reported outcome measures (PROMs) were collected, including scores on the Oswestry Disability Index (ODI), visual analog scale (VAS) for leg and back pain, and EQ-5D. Forty-five patients (24 males) with a mean ± SD age of 71.8 ± 5.6 years were included. Sagittal balance showed statistically significant improvement, with the mean SVA decreasing from 52.3 mm preoperatively to 33.9 mm postoperatively (p = 0.0001). The authors found an increase in LL, from mean -41.5° preoperatively to -43.9° postoperatively, but this was not statistically significant (p = 0.055). A statistically significant decrease in PI-LL mismatch from mean 8.4° preoperatively to 5.8° postoperatively was found (p = 0.002). All PROM scores showed significant improvement after spinal decompression surgery. The correlations between SVA and all PROMs were statistically significant at both preoperative and postoperative time points, although most correlations were weak except for those between preoperative SVA and ODI (r = 0.55) and between SVA and VAS for leg pain (r = 0.58). Sagittal balance and PROMs show improvement at short-term follow-up evaluations in patients who have undergone decompression alone for lumbar spinal stenosis.

Changes in pain scores and walking distance after epidural steroid injection in patients with lumbar central spinal stenosis.

Lumbar spinal stenosis is a common degenerative disorder that is characterized by pain and neurogenic claudication. Previous studies have evaluated the effects of an epidural steroid injection (ESI) on spinal stenosis, based on changes to the spinal canal diameter.This study aimed to examine the impact of the ESI on pain scores and walking distance in patients with lumbar central spinal stenosis, stratified based on disease severity, which was graded according to the degree of cauda equina separation.We reviewed the medical records of patients who received the ESI for lumbar spinal central canal stenosis. A total of 128 patients were divided into moderate and severe groups, based on the degree of cauda equina separation.Relative to baseline values, 2 weeks after the ESI, the moderate group showed a significant decrease in the numeric rating scale (NRS) scores and an increase in walking distance. Meanwhile, the severe group showed a significant decrease in the NRS scores and no significant change in walking distance. The moderate group had lower NRS scores and a longer walking distance than did the severe group 2 weeks after the ESI. The proportion of patients with improved levels of satisfaction was higher in the moderate group than in the severe group.Lumbar interlaminar ESI may reduce pain scores and increase walking distance in patients with moderate lumbar spinal central canal stenosis. Patients with moderate spinal stenosis achieved better outcomes than did patients with severe stenosis.

Physical Predictors of Favorable Postoperative Outcomes in Patients Undergoing Laminectomy or Laminotomy for Central Lumbar Spinal Stenosis: Secondary Analysis of a Randomized Controlled Trial.

Study DesignSecondary analysis of a randomized controlled trial.ObjectiveTo identify preoperative physical variables associated with favorable postoperative outcome in individuals undergoing laminectomy or laminotomy for degenerative central lumbar spinal stenosis.Summary of Background DataClinical or condition specific variables have most commonly been studied as predictors of postoperative outcome in lumbar spinal stenosis. If associated to favorable postoperative outcome, modifiable physical variables would inform prehabilitation interventions for patients with degenerative central lumbar spinal stenosis.MethodsPatients awaiting surgery for central lumbar spinal stenosis were recruited to participate in a randomized controlled trial. Following baseline data collection of demographics, clinical portrait and physical testing, participants were randomized to either 6-week active prehabilitation program or hospital standard care. Complete baseline and postoperative data were obtained from 58 participants which were included in the present analysis. Favorable postoperative outcome was determined based on two outcome measures. Favorable outcome was defined as a decrease of ≥30% on the Numerical Rating Scale for leg pain intensity and a decrease of ≥30% on the Oswestry Disability Index for low back disability. Baseline physical variables were used to conduct binary logistic regression.ResultsSixty percent of participants were determined as having a favorable postoperative outcome. None of the included physical variables were found to be predictors of a favorable postoperative outcome based on leg pain intensity and low back pain-associated disability [trunk flexors muscle strength (OR = 0.73; 95%CI (0.02–27.12)] lumbar extensors muscle endurance [OR= 1.09; 95%CI (0.95–1.24)] total ambulation time [OR = 1.00 95%CI (0.99–1.01)] lumbar active range of motion in extension [OR = 1.08; 95%CI (0.95–1.23)] and knee extensors muscle strength [OR=1.02; 95%CI (0.98–1.06)].ConclusionResults show that none of the investigated variables, all related to low back and lower limbs physical capacity, were predictors of postoperative recovery. Further testing in larger cohort is needed to assess the full potential of physical outcome measures as predictors of postoperative recovery.