Lumbar intervertebral instability: a review

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

Aims

We compared decompression alone to decompression with fusion surgery for lumbar spinal stenosis, with or without degenerative spondylolisthesis (DS). The aim was to evaluate if five-year outcomes differed between the groups. The two-year results from the same trial revealed no differences.

Methods

The Swedish Spinal Stenosis Study was a multicentre randomized controlled trial with recruitment from September 2006 to February 2012. A total of 247 patients with one- or two-level central lumbar spinal stenosis, stratified by the presence of DS, were randomized to decompression alone or decompression with fusion. The five-year Oswestry Disability Index (ODI) was the primary outcome. Secondary outcomes were the EuroQol five-dimension questionnaire (EQ-5D), visual analogue scales for back and leg pain, and patient-reported satisfaction, decreased pain, and increased walking distance. The reoperation rate was recorded.

Results

Five-year follow-up was completed by 213 (95%) of the eligible patients (mean age 67 years; 155 female (67%)). After five years, ODI was similar irrespective of treatment, with a mean of 25 (SD 18) for decompression alone and 28 (SD 22) for decompression with fusion (p = 0.226). Mean EQ-5D was higher for decompression alone than for fusion (0.69 (SD 0.28) vs 0.59 (SD 0.34); p = 0.027). In the no-DS subset, fewer patients reported decreased leg pain after fusion (58%) than with decompression alone (80%) (relative risk (RR) 0.71 (95% confidence interval (CI) 0.53 to 0.97). The frequency of subsequent spinal surgery was 24% for decompression with fusion and 22% for decompression alone (RR 1.1 (95% CI 0.69 to 1.8)).

Conclusion

Adding fusion to decompression in spinal stenosis surgery, with or without spondylolisthesis, does not improve the five-year ODI, which is consistent with our two-year report. Three secondary outcomes that did not differ at two years favoured decompression alone at five years. Our results support decompression alone as the preferred method for operating on spinal stenosis.

Three Stages on Magnetic Resonance Imaging of Lumbar Degenerative Spine

PURPOSES

To propose a new lumbar degenerative staging system using the current radiological classification system.

METHODS

A cross-sectional analysis of retrospective databases between January 2018 and December 2022 was performed. Total of 410 patients for Modic changes, paravertebral muscle fat infiltration, disc degeneration, articular process degeneration, vertebral endplate degeneration and other structures, and disc displacement, Spondylolisthesis, and stenosis, and grouped patients according to stage were assessed. Visual analog scale, Japanese Orthopaedic Association, and Oswestry Disability Index scores were used to assess low back pain strength, neurological function, and quality of life, respectively.

RESULTS

The lumbar degeneration staging system consists of 8 variables, which can be divided into 3 steps: early, middle and late, and the correlation between each variable is strong (P < 0.05). The later the staging, the worse the Japanese Orthopaedic Association, visual analog scale, and Oswestry Disability Index scores.

CONCLUSIONS

Patients with later stages have worse clinical scores. This staging system recommends a uniform classification to assess lumbar degeneration.

Finite element analysis of endoscopic cross-overtop decompression for single-segment lumbar spinal stenosis based on real clinical cases

Introduction: For severe degenerative lumbar spinal stenosis (DLSS), the conventional percutaneous endoscopic translaminar decompression (PEID) has some limitations. The modified PEID, Cross-Overtop decompression, ensures sufficient decompression without excessive damage to the facet joints and posterior complex integrity. Objectives: To evaluate the biomechanical properties of Cross-Overtop and provide practical case validation for final decision-making in severe DLSS treatment. Methods: A finite element (FE) model of L4-L5 (M0) was established, and the validity was verified against prior studies. Endo-ULBD (M1), Endo-LOVE (M2), and Cross-Overtop (M3) models were derived from M0 using the experimental protocol. L4-L5 segments in each model were evaluated for the range of motion (ROM) and disc Von Mises stress extremum. The real clinical Cross-Overtop model was constructed based on clinical CT images, disregarding paraspinal muscle influence. Subsequent validation using actual FE analysis results enhances the credibility of the preceding virtual FE analysis. Results: Compared with M0, ROM in surgical models were less than 10°, and the growth rate of ROM ranged from 0.10% to 11.56%, while those of disc stress ranged from 0% to 15.75%. Compared with preoperative, the growth rate of ROM and disc stress were 2.66%-11.38% and 1.38%-9.51%, respectively. The ROM values in both virtual and actual models were less than 10°, verifying the affected segment stability after Cross-Overtop decompression. Conclusion: Cross-Overtop, designed for fully expanding the central canal and contralateral recess, maximizing the integrity of the facet joints and posterior complex, does no significant effect on the affected segmental biomechanics and can be recommended as an effective endoscopic treatment for severe DLSS.

The Relationship Between MRI Findings of Posterior Ligamentous Complex and Lumbar Instability in Degenerative Spondylolisthesis

Background

To determine the factors in posterior ligamentous complex indicating lumbar instability in patients diagnosed with degenerative spondylolisthesis on conventional magnetic resonance imaging (MRI).

Methods

We retrospectively analyzed patients who underwent PLIF surgery for degenerative spondylolisthesis at our institution between 2018 and 2020 and who had complete eligible preoperative imaging data for review and study, including lumbar MRI and anteroposterior and flexion-extension radiographs.

Results

Fifty-three patients were confirmed to have lumbar instability (Unstable Group, 44%), while sixty-seven patients (Stable Group, 56%) did not have instability on radiographs. The patients in the stable group had more advanced status of the degeneration of intervertebral disc than in the unstable group (p<0.05). The degeneration of supraspinous ligament (SSL) was more severe in the unstable group (p<0.05). Compared with the patients with rotatory instability, advanced degeneration of interspinous ligament (ISL) and SSL was observed in patients with translatory instability (p<0.05). However, there was no significant difference with regard to the height of the spinous process and the interspinous distance in patients with or without instability.

Conclusion

This MRI analysis showed that abnormal segmental motion is closely associated with the pathological characteristics of supraspinal ligament. Advanced degeneration of SSL in patients with degenerative spondylolisthesis should raise the suspicion for lumbar instability and additional evaluations. The status of ISL and ligamentum flavum (LF) may not be helpful for the diagnosis of lumbar instability. Functional radiographs combined with MRI may provide valuable information when diagnosing lumbar instability in patients with mechanical back pain.

Reference Data for Diagnosis of Spondylolisthesis and Disc Space Narrowing Based on NHANES-II X-rays

Robust reference data, representing a large and diverse population, are needed to objectively classify measurements of spondylolisthesis and disc space narrowing as normal or abnormal. The reference data should be open access to drive standardization across technology developers. The large collection of radiographs from the 2nd National Health and Nutrition Examination Survey was used to establish reference data. A pipeline of neural networks and coded logic was used to place landmarks on the corners of all vertebrae, and these landmarks were used to calculate multiple disc space metrics. Descriptive statistics for nine SPO and disc metrics were tabulated and used to identify normal discs, and data for only the normal discs were used to arrive at reference data. A spondylolisthesis index was developed that accounts for important variables. These reference data facilitate simplified and standardized reporting of multiple intervertebral disc metrics.

Prediction Model and Risk Factor Analysis of Adjacent Segment Disease After L4-5 Transforaminal Lumbar Interbody Fusion Through Preoperative Radiographic Features

STUDY DESIGN

A retrospective study.

OBJECTIVE

To investigate the risk of adjacent segment disease (ASD) after L4-5 transforaminal lumbar interbody fusion (TLIF) in patients diagnosed with lumbar spinal stenosis (LSS), a prediction model for ASD is established and validated.

METHODS

A retrospective study was carried out on a sample of 290 patients who underwent L4-5 TLIF at Zhongda Hospital, Southeast University, from January 2015 to January 2021. The study collected baseline data and preoperative radiographic features of L3-4 and L5-S1. The determination of the outcome variable was based on X-ray results spanning over 24 months and JOA scores. Multivariate logistic regression was used to identify the risk factors in constructing a nomogram.

RESULTS

Independent risk factors for L3-4 degeneration after TLIF included osteoarthritis of L3-4 facet joints, L3-4 foraminal stenosis, L4 upper endplate osteochondritis, L3-4 local lordosis angle, and L3-4 spinal stenosis. Independent risk factors for L5-S1 degeneration after TLIF included osteoarthritis of L5-S1 facet joints, L5-S1 intervertebral disc degeneration, L5-S1 spinal stenosis, L5-S1 coronal imbalance, and S1 upper endplate osteochondritis. A predictive model was developed. The AUC for the prediction models at L3-4 and L5-S1 were .945 and .956. The calibration curve demonstrated good consistency between the predicted and actual probabilities. The DCA curve indicated the clinical benefit and practical value of this predictive model.

CONCLUSION

This study established nomograms for postoperative degeneration at L3-4 and L5-S1 based on selected preoperative radiographic features. These models provide a valuable auxiliary decision-making system for clinicians and aid in early surgical decisions.

Supplementary posterior fusion in patients operated on employing TLIF may decrease the instrumentation failure rate

Background

It is supposed that additional posterior fusion may provide additional stability of the pedicle screw; however, the clinical impact of additional posterior fusion in patients treated with TLIF remains uncertain. The objective of this study is to assess the clinical efficacy of circumferential fusion in patients treated with TLIF.

Materials and methods

This is a single-center retrospective evaluation of consecutive 179 patients with degenerative lumbar stenosis and instability of spinal segments. Patients with axial pain and neurogenic claudication or radiculopathy associated with spinal stenosis were enrolled during the period from 2012 to 2018. Transforaminal lumbar interbody fusion (TLIF) with a single cage was used to treat patients. In 118 cases a supplementary posterior fusion was made. The duration of follow-up accounted for 24 months, logistic regression analysis was used to assess factors that influence the complication rate.

Results

The rate of pedicle screw loosening was growing with radiodensity getting decreased and was more frequent in patients with two level fusion. An increase in pedicle screw loosening rate correlated with anterior nonunion Tan 2 and 3 grade while both posterior complete and incomplete fusion resulted in a decline in the complication rate. Lumbosacral fusion, bilateral facet joints` resection and laminectomy turned out to be insignificant factors. The overall goodness of fit of the estimated general multivariate model was χ2 = 87.2230; P < 0.0001. To confirm clinical relevance of those findings, a univariate logistic regression was performed to assess the association between clinically significant pedicle screw instability and posterior fusion in patients operated on employing TLIF. The results of logistic regression analysis demonstrate that additional posterior fusion may decrease the rate of instrumentation failure that requires revision surgery in patients treated with TLIF [B0 = 1.314321; B1 = -3.218279; p = 0.0023; OR = 24.98507; 95% CI (3.209265; 194.5162), the overall goodness of fit of the estimated regression was χ2 = 22.29538, p = <0.0001].

Conclusion

Circumferential fusion in patients operated on employing TLIF is associated with a decline in the rate of pedicle screw loosening detected by CT imaging and clinically significant instrumentation failure.

Sample Preparation Method for MALDI Mass Spectrometry Imaging of Fresh-Frozen Spines

Technologies assessing the lipidomics, genomics, epigenomics, transcriptomics, and proteomics of tissue samples at single-cell resolution have deepened our understanding of physiology and pathophysiology at an unprecedented level of detail. However, the study of single-cell spatial metabolomics in undecalcified bones faces several significant challenges, such as the fragility of bone, which often requires decalcification or fixation leading to the degradation or removal of lipids and other molecules. As such, we describe a method for performing mass spectrometry imaging on undecalcified spine that is compatible with other spatial omics measurements. In brief, we use fresh-frozen rat spines and a system of carboxyl methylcellulose embedding, cryofilm, and polytetrafluoroethylene rollers to maintain tissue integrity while avoiding signal loss from variations in laser focus and artifacts from traditional tissue processing. This reveals various tissue types and lipidomic profiles of spinal regions at 10 μm spatial resolutions using matrix-assisted laser desorption/ionization mass spectrometry imaging. We expect this method to be adapted and applied to the analysis of the spinal cord, shedding light on the mechanistic aspects of cellular heterogeneity, development, and disease pathogenesis underlying different bone-related conditions and diseases. This study furthers the methodology for high spatial metabolomics of spines and adds to the collective efforts to achieve a holistic understanding of diseases via single-cell spatial multiomics.

Reoperations After Percutaneous Endoscopic Transforaminal Decompression for Treating Lumbar Spinal Stenosis: Incidence and Predictors

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

The main purpose of the present study was to report the incidence and identify predictors of reoperation in patients with lumbar spinal stenosis (LSS) treated with percutaneous endoscopic transforaminal decompression (PETD).

METHODS

This study retrospectively reviewed consecutive patients with LSS who underwent PETD at our center between January 2016 and July 2020. The incidence of reoperations was calculated. We then designed a surgical period-matched case-control study to identify predictors among demographic data, clinical baseline data, and imaging parameters.

RESULTS

This study identified 496 eligible patients. 33 (6.7%) patients underwent reoperation with a mean follow-up of 3 years, consisting 22 (4.4%) at the index level and 11 (2.2%) at the adjacent levels. There were significant differences in age and age-adjusted Charlson comorbidity index (AACCI) between the two groups, with younger age (P = .004) and lower AACCI (P = .019) in reoperation group. Age was identified as the sole independent predictor (P = .006). The duration of symptoms ≥12 months (P = .034) and the presence of heart problems (P = .012) were recognized as specific predictors among patients younger than 65 years.

CONCLUSIONS

In a mean follow-up of 3 years, the incidence of reoperation in LSS treated with PETD was 6.7%. A younger age was the independent predictor for reoperation. Younger patients with the duration of symptoms ≥12 months or without heart problems were more likely to undergo a second operation. Prospective randomized controlled trials are required to confirm these findings.

Surgical Strategy and Outcomes of Full Endoscopic Lumbar Discectomy for Recurrent Lumbar Disk Herniation Following a Previous Full Endoscopic Lumbar Discectomy

OBJECTIVE

Recurrent lumbar disc herniation (RLDH) cannot be prevented after full endoscopic lumbar discectomy (FELD), and the optimal surgical treatment for RLDH after FELD remains controversial. The aim of the study was to suggest a surgical strategy for FELD to treat RLDH following a previous FELD and to present surgical outcomes.

METHODS

Between February 2015 and March 2022, 68 patients with RLDH were surgically treated with FELD retrospectively. An original approach was suggested for the treatment of early recurrence (24 h-2 weeks). The full endoscopic transforaminal technique (FETD) was considered for patients requiring local anesthesia, and in RLDH with FETD indications or FEID technological difficulties. The full endoscopic interlaminar technique (FEID) was chosen in RLDH with FEID indications. Both FEID and FETD were suitable if no FEID or FETD technological difficulties existed. Clinical efficacy was evaluated using the visual analog scale (VAS) score, Oswestry disability index (ODI), and modified MacNab criteria. Postoperative follow-up data at 24 h, 3 months, and final-follow-up were recorded. Operation time and clinical outcomes were assessed with t test. p-value < 0.05 was considered statistically significant.

RESULTS

All 68 patients had an average follow-up time of 23.8 months (range, 6-76 months). In the 13 cases of early recurrence, the operation time (32.30 ± 9.67 vs. 58.00 ± 6.16 min) in the original surgical approach group was shorter than that in the changing surgical approach group (p < 0.05). In the 28 cases of L4/5 FETD recurrence (>2 weeks), the operation time (66.17 ± 12.18 vs. 53.60 ± 5.45 min) in the FETD group was more than that in the FEID group (p < 0.05). In the 22 cases of L5S1 recurrence (>2 weeks), the operation time (55.75 ± 8.79 vs. 79.33 ± 6.65 min) in the FEID group was shorter than in the FETD group (p < 0.05). The postoperative VAS and ODI scores at 24 h, 3 months, and final-follow up were all significantly improved, compared with their preoperative counterparts (p < 0.05). Based on the modified MacNab criteria, 88.23% of patients showed excellent or good results. Re-recurrence occurred in three patients at 3 months. No surgical complications were observed in any of the 68 cases.

CONCLUSION

FELD is a safe and effective treatment option for RLDH with previous FELD. For early recurrence, the original approach was suggested. Both FEID and FETD were effective and safe for recurrence (>2 weeks), but FEID seemed more efficient for L4/5 RLDH after previous FETD and for L5S1 RLDH.

Spatial lipidomics of fresh-frozen spines

Technologies assessing the lipidomics, genomics, epigenomics, transcriptomics, and proteomics of tissue samples at single-cell resolution have deepened our understanding of physiology and pathophysiology at an unprecedented level of detail. However, the study of single-cell spatial metabolomics in undecalcified bones faces several significant challenges, such as the fragility of bone which often requires decalcification or fixation leading to the degradation or removal of lipids and other molecules and. As such, we describe a method for performing mass spectrometry imaging on undecalcified spine that is compatible with other spatial omics measurements. In brief, we use fresh-freeze rat spines and a system of carboxyl methylcellulose embedding, cryofilm, and polytetrafluoroethylene rollers to maintain tissue integrity, while avoiding signal loss from variations in laser focus and artifacts from traditional tissue processing. This reveals various tissue types and lipidomic profiles of spinal regions at 10 μm spatial resolutions using matrix-assisted laser desorption/ionization mass spectrometry imaging. We expect this method to be adapted and applied to the analysis of spinal cord, shedding light on the mechanistic aspects of cellular heterogeneity, development, and disease pathogenesis underlying different bone-related conditions and diseases. This study furthers the methodology for high spatial metabolomics of spines, as well as adds to the collective efforts to achieve a holistic understanding of diseases via single-cell spatial multi-omics.

Unilateral Bi/Multi-Portal Endoscopy for the Treatment of Complicated Lumbar Degenerative Diseases with Utilization of Uniaxial Spinal Endoscope, Instead of Arthroscope: Technique Note and Clinical Results

Objective

This article aims to discuss a novel surgical strategy, referred to as unilateral bi/multi-portal endoscopy (UME), which used a uniaxial spinal endoscope instead of an arthroscope in the traditional unilateral biportal endoscopy (UBE) surgical procedure in our study of the treatment of complicated lumbar degenerative diseases.

Methods

This retrospective study included 42 patients diagnosed with high-migrated lumbar disc herniation and bilateral spinal stenosis who underwent UME surgery from January 2021 to December 2021. Patients included 20 men and 22 women, with an average age of 55.97±14.92 years. The average follow-up period was 13.19 months. The demographic data, operation time (min), and complications were recorded and analyzed. The visual analogue scale (VAS), Oswestry Disability Index (ODI) scores were used to evaluate the surgical outcomes. Three-dimensional CT scans and MRI were conducted to evaluate the radiographic improvement.

Results

A total of 26 patients were diagnosed with lumbar disc herniation and 16 with lumbar spinal stenosis. All 42 patients underwent UME surgery and achieved satisfactory outcomes. The operation time was 154.46±46.09 min. The average follow-up time was 13.19±1.33 months. The preoperative back pain (VAS-Back) and the last follow-up VAS-Back were 3.84±1.00 and 0.70±0.46, respectively (P < 0.05). The preoperative leg pain (VAS-Leg) and the last follow-up VAS-Leg were 6.46±1.08 and 1.03±0.64, respectively (P <0.05). Significant differences existed between preoperative ODI scores (58.70±11.22%) and the last follow-up ODI scores (9.24±3.04%; P<0.05). All patients achieved significant pain relief and functional improvement after the surgery. No severe complications occurred, except for two cases of postoperative dysesthesia and one case suffered from vertebral compression fractures induced by a postoperative accidental injury. Symptoms of numbness disappeared within one week with treatment using dexamethasone and neurotrophic drugs. The vertebral fracture case recovered with percutaneous kyphoplasty treatment.

Conclusion

This study suggests that UME is a promising treatment strategy for high-migrated disc herniation and bilateral spinal stenosis.

Postoperative cage migration and subsidence following TLIF surgery is not associated with bony fusion

Pseudarthrosis following transforaminal interbody fusion (TLIF) is not infrequent. Although cage migration and subsidence are commonly regarded as evidence of the absence of solid fusion, there is still no evidence of the influence of cage migration and subsidence on fusion. This study aimed to evaluate cage migration and subsidence using computed tomography (CT) DICOM data following lumbar interbody fusion. The effects of cage migration and subsidence on fusion and clinical outcomes were also assessed. A postoperative CT data set of 67 patients treated with monosegmental TLIF was analyzed in terms of cage position. To assess the effects of cage migration and subsidence on fusion, 12-month postoperative CT scans were used to assess fusion status. Clinical evaluation included the visual analog scale for pain and the Oswestry Disability Index. Postoperative cage migration occurred in 85.1% of all patients, and cage subsidence was observed in 58.2%. Radiological signs of pseudarthrosis was observed in 7.5% of the patients Neither cage migration nor subsidence affected the clinical or radiographic outcomes. No correlation was found between clinical and radiographic outcomes. The incidence of cage migration was considerable. However, as cage migration and subsidence were not associated with bony fusion, their clinical significance was considered limited.

Comparison of the results of open PLIF versus UBE PLIF in lumbar spinal stenosis: postoperative adjacent segment instability is lesser in UBE

OBJECTIVE

To compare the difference in efficacy between open PLIF and UBE for lumbar spinal stenosis and the effect on postoperative adjacent segment instability.

METHOD

The clinical data of 37 patients with PLIF and 32 patients with UBE for lumbar spinal stenosis were retrospectively analyzed to compare the differences in perioperative conditions and short- and medium-term outcomes.

RESULTS

All 69 patients completed the surgery successfully. The operating time, number of intraoperative fluoroscopies and hospital days were higher in the UBE group than in the open PLIF group. Intraoperative bleeding and postoperative drainage were lower than in the open PLIF group (P < 0.05). The visual analogue scale (VAS) of low back pain was lower in the UBE group than in the open PLIF group at 1 month and 3 months postoperatively (P < 0.05), and there were no statistically significant VAS scores for low back pain in the two groups at 1 day and 6 months postoperatively (P > 0.05). Leg pain VAS scores were lower in the UBE group than in the open PLIF group at 1 month, 3 months and 6 months postoperatively (P < 0.05), and leg pain VAS scores were not statistically significant in both groups at 1 day postoperatively (P > 0.05). The ODI index was lower in the UBE group than in the open PLIF group at 1 day and 1 month postoperatively (P < 0.05) and was not statistically significant in the two groups at 3 months and 6 months postoperatively (P > 0.05). There was no statistically significant difference between the two groups in postoperative interbody height, sagittal diameter of the spinal canal, efficacy of modified MacNab and interbody fusion (P > 0.05). The open PLIF group was more prone to postoperative adjacent vertebral instability than the UBE group, and the difference was statistically significant (P < 0.05).

CONCLUSION

With appropriate indications, the open PLIF group and the UBE group had similar short- and medium-term clinical outcomes for the treatment of lumbar spinal stenosis, but patients in the UBE group had better symptomatic improvement than the open PLIF group at 3 months postoperatively, and the effect on postoperative adjacent vertebral instability was smaller in the endoscopic group than in the open PLIF group.

A Simple Preoperative Score Predicting Failure Following Decompression Surgery for Degenerative Lumbar Spinal Stenosis

BACKGROUND CONTEXT

Proper patient selection is crucial for the outcome of surgically treated degenerative lumbar spinal stenosis (DLSS). Nevertheless, there is still not a clear consensus regarding the optimal treatment option for patients with DLSS.

PURPOSE

To investigate the treatment failure rate and introduce a simple, preoperative score to aid surgical decision-making.

STUDY DESIGN/SETTING

Retrospective observational study.

PATIENT SAMPLE

Four hundred forty-five patients who underwent surgical decompression for DLSS.

OUTCOME MEASURES

Treatment failure (defined as conversion to a fusion of a previously decompressed level) of lumbar decompression.

MATERIALS AND METHODS

Several risk factors associated with worse outcomes and treatment failures, such as age, body mass index, smoking status, previous surgery, low back pain (LBP), facet joint effusion, disk degeneration, fatty infiltration of the paraspinal muscles, the presence of degenerative spondylolisthesis and the facet angulation, were investigated.

RESULTS

At a mean follow-up of 44±31 months, 6.5% (29/445) of the patients underwent revision surgery with spinal fusion at an average of 3±9 months following the lumbar decompression due to low back or leg pain. The baseline LBP (≥7) [odds ratio (OR)=5.4, P <0.001], the presence of facet joint effusion (>2 mm) in magnetic resonance imaging (OR=4.2, P <0.001), and disk degeneration (Pfirrmann >4) (OR=3.2, P =0.03) were associated with an increased risk for treatment failure following decompression for DLSS. The receiver operating characteristic curve analysis demonstrated that a score≥6 points yielded a sensitivity of 90% and specificity of 64% for predicting a treatment failure following lumbar decompression for DLSS in the present cohort.

CONCLUSIONS

The newly introduced score quantifying amounts of LBP, facet effusions, and disk degeneration, could predict treatment failure and the need for revision surgery for DLSS patients undergoing lumbar decompression without fusion. Patients with scores >6 have a high chance of needing fusion following decompression surgery.

LEVEL OF EVIDENCE

Retrospective observational study, Level III.

Unilateral microscopic approach for lumbar spinal stenosis decompression: a scoping review

BACKGROUND

Microscopic unilateral laminotomy for bilateral decompression (ULBD) is a minimally invasive technique used in the treatment of lumbar spinal stenosis and could limit spinal instability and be associated with better clinical outcomes. However, there is ongoing debate regarding its utility compared to conventional laminectomy (CL). The primary objective was to collate and describe the current evidence base for ULBD, including perioperative parameters, functional outcomes, and complications. The secondary objective was to identify operative techniques.

METHODS

A scoping review was conducted between January 1990 and August 2022 according to the PRISMA extension for scoping reviews (PRISMA-ScR) guidelines. Major databases were searched for full text English articles reporting on outcomes following microscopic unilateral laminotomy in patients with lumbar spinal stenosis.

RESULTS

Seventeen articles met the inclusion criteria. Two studies were randomised controlled trials. Two studies were prospective data collection and the rest were retrospective analysis. Three studies compared ULBD with CL. ULBD preserves the osteoligamentous complex and may be associated with shorter operative time, less blood loss, and similar clinical outcomes when compared to CL.

CONCLUSION

This review highlights that ULBD aims to minimise disruption to the normal posterior spinal anatomy and may have acceptable clinical outcomes. It also highlights that it is difficult to draw valid conclusions given there are limited data available as most studies identified were retrospective or did not have a comparator group.

The reliability of video fluoroscopy, ultrasound imaging, magnetic resonance imaging and radiography for measurements of lumbar spine segmental range of motion in-vivo: A review

BACKGROUND

Lower back pain (LBP) is a principal cause of disability worldwide and is associated with a variety of spinal conditions. Individuals presenting with LBP may display changes in spinal motion. Despite this, the ability to measure lumbar segmental range of motion (ROM) non-invasively remains a challenge.

OBJECTIVE

To review the reliability of four non-invasive modalities: Video Fluoroscopy (VF), Ultrasound imaging (US), Magnetic Resonance Imaging (MRI) and Radiography used for measuring segmental ROM in the lumbar spine in-vivo.

METHODS

The methodological quality of seventeen eligible studies, identified through a systematic literature search, were appraised.

RESULTS

The intra-rater reliability for VF is excellent in recumbent and upright positions but errors are larger for intra-rater repeated movements and inter-rater reliability shows larger variation. Excellent results for intra- and inter-rater reliability are seen in US studies and there is good reliability within- and between-day. There is a large degree of heterogeneity in MRI and radiography methodologies but reliable results are seen.

CONCLUSIONS

Excellent reliability is seen across all modalities. However, VF and radiography are limited by radiation exposure and MRI is expensive. US offers a non-invasive, risk free method but further research must determine whether it yields truly consistent measurements.

Decompression alone or decompression with fusion for lumbar spinal stenosis: a randomized clinical trial with two-year MRI follow-up

AIMS

The aims of this study were first, to determine if adding fusion to a decompression of the lumbar spine for spinal stenosis decreases the rate of radiological restenosis and/or proximal adjacent level stenosis two years after surgery, and second, to evaluate the change in vertebral slip two years after surgery with and without fusion.

METHODS

The Swedish Spinal Stenosis Study (SSSS) was conducted between 2006 and 2012 at five public and two private hospitals. Six centres participated in this two-year MRI follow-up. We randomized 222 patients with central lumbar spinal stenosis at one or two adjacent levels into two groups, decompression alone and decompression with fusion. The presence or absence of a preoperative spondylolisthesis was noted. A new stenosis on two-year MRI was used as the primary outcome, defined as a dural sac cross-sectional area ≤ 75 mm² at the operated level (restenosis) and/or at the level above (proximal adjacent level stenosis).

RESULTS

A total of 211 patients underwent surgery at a mean age of 66 years (69% female): 103 were treated by decompression with fusion and 108 by decompression alone. A two-year MRI was available for 176 (90%) of the eligible patients. A new stenosis at the operated and/or adjacent level occurred more frequently after decompression and fusion than after decompression alone (47% vs 29%; p = 0.020). The difference remained in the subgroup with a preoperative spondylolisthesis, (48% vs 24%; p = 0.020), but did not reach significance for those without (45% vs 35%; p = 0.488). Proximal adjacent level stenosis was more common after fusion than after decompression alone (44% vs 17%; p < 0.001). Restenosis at the operated level was less frequent after fusion than decompression alone (4% vs 14%; p = 0.036). Vertebral slip increased by 1.1 mm after decompression alone, regardless of whether a preoperative spondylolisthesis was present or not.

CONCLUSION

Adding fusion to a decompression increased the rate of new stenosis on two-year MRI, even when a spondylolisthesis was present preoperatively. This supports decompression alone as the preferred method of surgery for spinal stenosis, whether or not a degenerative spondylolisthesis is present preoperatively.Cite this article: Bone Joint J 2022;104-B(12):1343-1351.

Full Endoscopic Ligamentum Flavum Sparing Unilateral Laminotomy for Bilateral Recess Decompression: Surgical Technique and Clinical Results

OBJECTIVE

Interlaminar endoscopic spine surgery has been introduced and utilized for lumbar lateral recess decompression. We modified this technique and utilized it for bilateral lateral recess stenoses without significant central stenosis. Here we present the surgical details and clinical outcome of ligamentum flavum sparing unilateral laminotomy for bilateral recess decompression (ULBRD).

METHODS

Prospectively collected registry for full-endoscopic surgeries was reviewed retrospectively. One hundred eighty-two consecutive cases from a single center between September 2015 and March 2021 were reviewed and 57 of them whom underwent ULBRD were enrolled for analysis. Basic patient demographic data, perioperative details, surgeryrelated complications, and clinical outcome were reviewed. The detailed surgical technique is presented as well.

RESULTS

Among the 57 patients enrolled, 37 were males while the other 20 were females. The mean age was 58.53 ± 14.51 years, and a bimodal age distribution at the age of mid-fifties and mid-sixties or older was noted. The later age-peak was related to coexistence of degenerative scoliosis. The average operative time per lamina was 70.34 ± 20.51 minutes and mean length of stay was 0.56 ± 0.85 days. Four perioperative complications were reported (7.0%) and the overall reoperation rate at the index level within 1 year was 8.8%. The preoperative back/leg visual analogue scale scores and functional outcome scales including EuroQol-5 dimension questionnaire, Oswestry Disability Index presented significant improvement immediately after surgery and were maintained until final follow-up.

CONCLUSION

ULBRD for bilateral lateral recess stenoses without significant central stenosis resulted in good clinical outcomes with acceptably low perioperative complications rates. Sufficient decompression was achieved with the central ligamentum flavum being preserved.

Age-related radiographic parameters difference between the degenerative lumbar spinal stenosis patients and healthy people and correlation analysis

OBJECTIVES

To identify age-related radiographic risk factors for degenerative lumbar spinal stenosis (DLSS) and analyze correlations among them.

METHODS

A total of 180 cases were enrolled in this study, and lumbar magnetic resonance was performed. Among them, 93 cases suffered DLSS and lumbar dynamic X-ray was examined. And following parameters were measured and evaluated: intervertebral disk height (IDH), the ratio of IDH(IDH_L4-5/L3-4), initial IDH of L4-5(iIDH_L4-5) in the DLSS group, disk degeneration (DD), cartilaginous endplate failure (CEF), Modic changes, the thickness of ligamentum flavum (LF), range of intervertebral motion (ROM), facet joint opening (FJO), facet joint angle (FJA), the standard cross-sectional area (SCSA) of the multifidus, erector spinae, and psoas major muscles. The data of two groups were compared, and the possible risk factors of DLSS were analyzed.

RESULTS

Compared with the control group, the DLSS group had higher IDH except for L4-5 and larger iIDH_L4-5 (P < 0.05). Significant differences were shown in CEF and the thickness of LF at L1-S1 and DD at L4-5 (P < 0.05). The DLSS group had smaller SCSA of multifidus, erector spinae, and psoas major muscles but greater FJA, FJO (P < 0.05). And the risk of DLSS increased when iIDH_L4-5 ≥ 10.73 mm, FJA ≥ 52.03° , or FJO ≥ 3.75 mm. IDH positively correlated with SCSA of multifidus and psoas major muscles and ROM at L1-S1 (P < 0.05). DD showed negative linear relations with SCSA of multifidus and psoas muscle and positive linear relation with CEF at L1-2, L2-3, and L5-S1 (P < 0.05).

CONCLUSION

Larger initial disk height and excessive CEF may induce DLSS by increasing intervertebral mobility to promote DD, and atrophied paravertebral muscles by weakening the stability of lumbar spine.

Prevalence of Thai People with Lumbar Instability and Associated Factors: A Cross-Sectional Study

Background

Lumbar instability has been extensively reported; however, the risk factors for lumbar instability remain poorly defined, and understanding this condition better would help health professionals and their patients.

Proposal

To determine the prevalence of lumbar instability in Thai people with chronic low back pain (CLBP) and explore the factors associated with lumbar instability in these patients.

Patients and Methods

Using multistage random sampling methods, 1762 participants with CLBP were enrolled in the study from six regions of Thailand. Data were collected using a paper-based questionnaire. Participants were interviewed by physical therapists in the hospital they attended. They were classified as having lumbar instability when they attained ≥7/14 items on the lumbar instability screening tool. Univariate and multivariate regression analysese were used to determine the possible factors associated with lumbar instability.

Results

There were 961 (54.54%) participants with lumbar instability and 801 (45.46%) participants without. The eight factors associated with lumbar instability were: (i) age ≥40 years (AOR: 1.36; 95% CI: 1.09-1.69); (ii) body mass index ≥25 kg/m² (AOR: 1.42; 95% CI: 1.16-1.74); (iii) having an underlying disease (AOR: 1.32; 95% CI: 1.06-1.65); (iv) frequent lifting ≥5 kg in occupational habits (AOR: 1.69; 95% CI: 1.36-2.09); (v) prolonged walking ≥4 hours per day (AOR: 1.31; 95% CI: 1.04-1.64); (vi) gardening in leisure time (AOR: 1.37; 95% CI: 1.10-1.71); (vii) other area of pain (AOR: 1.24; 95% CI: 1.01-2.52): and (viii) other area of numbness (AOR: 1.85; 95% CI: 1.50-2.27). When considering only women, prior pregnancy was associated with lumbar instability with OR of 1.76 (95% CI: 1.36-2.22), p-value <0.0001.

Conclusion

When treating patients with CLBP who are suspected to have lumbar instability, healthcare professionals should consider associated factors that might be modifiable targets for interventions to improve outcomes.

Comparison of posterior decompression techniques and conventional laminectomy for lumbar spinal stenosis

Objectives

To compare the efficacy of posterior decompression techniques with conventional laminectomy for lumbar spinal stenosis.

Methods

The Embase, PubMed, and Cochrane Library databases were searched with no language limitations from inception to January 13, 2022. The main outcomes were functional disability, perceived recovery, leg and back pain, complications. A random effects model was used to pooled data. Risk ratio (RR), mean difference (MD) and 95% confidence interval (CI) were used to report results. The study protocol was published in PROSPERO (CRD42022302218).

Results

14 trials including 1,106 participants were included in the final analysis. Bilateral laminotomy was significantly more efficacious in improve functionality than laminectomy [MD: -2.94; (95% CI, -4.12 to -1.76)]. Low incidence of iatrogenic instability due to bilateral laminectomy compared with laminectomy [RR: 0.11; (95% CI, 0.02 to 0.59)]. In addition, between those who received bilateral laminotomy and those undergoing laminectomy, the result showed significant difference regarding recovery [RR: 1.31; (95% CI, 1.03 to 1.67)].

Conclusions

This study provides evidence that bilateral laminotomy has advantages in functional recovery, postoperative stability, and postoperative rehabilitation outcomes. Further research is needed to determine whether posterior techniques provide a safe and effective option for conventional laminectomy.

Comparison of Kinematic Movement Patterns Between 2 Subgroups of Females With Low Back Pain and Healthy Women During Sit-to-Stand and Stand-to-Sit

The purpose of study was to compare the kinematic patterns of the thoracic, lumbar, and pelvis segments and hip joints between 2 low back pain subgroups and healthy women during sit-to-stand and stand-to-sit. Kinematic data of 44 healthy women and 2 subgroups of females with low back pain in 2 subgroups of movement system impairment model (rotation-extension [Rot.Ext] and rotation-flexion [Rot.Flex]) were recorded. Participants performed sit-to-stand and stand-to-sit at a preferred speed. Each task was divided into a pre buttock lifted off/on (pre-BOff/n) phase and a post-BOff/n phase. The Rot.Ext subgroup showed greater range of motion in the thoracic during pre-BOff phase of sit-to-stand (P < .001) and pre-BOn phase of stand-to-sit (P = .01) compared to the other 2 groups. The Rot.Flex subgroup displayed limited left hip joint excursion during sit-to-stand pre-BOff (P = .04) and stand-to-sit post-BOn phases (P = .02). The Rot.Flex subgroup showed greater pelvis tilt excursion during sit-to-stand post-BOff (P = .04) and stand-to-sit pre-BOn (P = .01) and post-BOn phases (P = .01). In subgroups of women with chronic low back pain, there were kinematic changes in adjacent body segments/joints of lumbar spine during sit-to-stand and stand-to-sit tasks.

Real-time assessment of anteroposterior stability of spinal segments

PURPOSE

While anteroposterior instability of spinal segments is regarded as an important biomechanical aspect in the clinical evaluation of lumbar pathologies, the reliability of the available diagnostic tools is limited and an intraoperative method to quantify stability is lacking. The aim of this study was to develop and validate an instrument to measure the anteroposterior stability of a spinal segments in real-time.

METHODS

Torsi of five fresh-frozen human cadavers were used for this study. After pedicle screw insertion, a specifically modified reposition tool composed with load and linear sensors was used to measure the segmental anteroposterior motion caused by 100 N anterior and posterior force during 5 loading cycles on either side of the instrumentation by two different operators. The spinal segments were then resected from the torsi and anteroposterior loading with ± 100 N was repeated in an advanced biomechanical spine testing setup as a reference measurement. The Inter-correlation coefficient (ICC) was used for validation of the "intraoperative" device.

RESULTS

Inter-operator repeatability of the measurements showed an ICC of 0.93 (p < 0.0001) and the bilateral (left-right) comparison had an ICC of 0.73 (p < 0.0001). The ICC resulting from the comparison to the reference measurement was 0.82 (p < 0.0001) without offset correction, and 0.9 (p < 0.0001) with offset correction. The ICC converged at this value already after two of the five performed loading cycles.

CONCLUSION

An accurate and reliable measurement tool is developed and validated for real-time quantification of anteroposterior stability of spinal segments and serves as a basis for future intraoperative use.

Does fusion status following posterolateral lumbar fusion in the treatment for stable lumbar degenerative spondylolisthesis affect the long-term surgical outcomes? A propensity score-weighted analysis of consecutive patients

BACKGROUND

The surgical strategy of lumbar degenerative spondylolisthesis (LDS) is controversial, especially regarding whether or not fusion should be used. Although some reports have indicated that decompression combined with fusion may be better than decompression alone in the treatment of LDS, the effect of fusion status after uninstrumented posterolateral lumbar fusion (PLF) on the outcomes of patients with stable LDS remains unknown. This study aimed to evaluate the surgical outcomes of uninstrumented PLF for stable LDS and clarify whether radiographic fusion status could affect surgical outcomes.

METHODS

A total of 93 consecutive patients who had undergone single-level uninstrumented PLF for Meyerding grade I LDS without preoperative dynamic instability with a minimum follow-up period of 5 years were retrospectively studied. Patients were divided into two groups: nonunion (52 patients) and union (41 patients). The primary outcomes were the 5-year percent recovery of postoperative Japanese Orthopaedic Association (JOA) scores, Oswestry Disability Index (ODI), Visual analog scale (VAS) scores, and reoperation rate. The outcome scores were compared between the groups using the inverse probability weighting method using propensity scores.

RESULTS

The union and nonunion groups had comparable weighted means of the 5-year postoperative clinical score for the percent recovery of the JOA score (70.2% vs. 71.1%, P = 0.86), ODI (14.5 vs.14.6, P = 0.98), VAS of low back pain (20.3 vs. 18.7 mm, P = 0.72), and VAS of leg pain (24.0 vs. 19.4 mm, P = 0.43). The reoperation rate was 2.4% (one case of adjacent segment pathology) in the union group and 0% in the nonunion group (P = 0.44).

CONCLUSION

The fusion status following uninstrumented PLF had no significant effect on the 5-year postoperative clinical outcomes and reoperation rate in patients with Meyerding grade I LDS without dynamic instability.

Degenerative Lumbar Spine Disease: Imaging and Biomechanics

Chronic low back pain (CLBP) is one of the most common diagnoses encountered when considering years lived with disability. The degenerative changes of the lumbar spine include a wide spectrum of morphological modifications visible on imaging, some of them often asymptomatic or not consistent with symptoms. Phenotyping by considering both clinical and imaging biomarkers can improve the management of CLBP. Depending on the clinical presentation, imaging helps determine the most likely anatomical nociceptive source, thereby enhancing the therapeutic approach by targeting a specific lesion. Three pathologic conditions with an approach based on our experience can be described: (1) pure painful syndromes related to single nociceptive sources (e.g., disk pain, active disk pain, and facet joint osteoarthritis pain), (2) multifactorial painful syndromes, representing a combination of several nociceptive sources (such as lumbar spinal stenosis pain, foraminal stenosis pain, and instability pain), and (3) nonspecific CLBP, often explained by postural (muscular) syndromes.

Prevalence of Lumbar Segmental Instability in Young Individuals with the Different Types of Lumbar Disc Herniation-Preliminary Report

Lumbar segmental instability (LSI) can cause pain and disability, and its background can be related to lumbar disc herniation (LDH). This retrospective study was conducted to analyze the prevalence of lumbar segmental instability (LSI) in young patients with different types of lumbar disc herniation (LDH). The study evaluated 133 individuals (18−25 years old) who suffered from LDH and underwent MRI and flexion-extension X-rays. Two groups were created: protrusion (PRO) and extrusion (EXT). LSI was scored positive when translatory motion was greater than 4 mm anteriorly or 2 mm posteriorly at the level of herniation. Statistica 13 was used to perform statistics. The LSI overall prevalence was 18.33% in PRO and 21.92% in EXT (p > 0.05). Out of all LSI positives, higher LSI incidence was observed in females compared to males; in PRO: 63.64%; in EXT: 68.75% (p > 0.05). LSI correlated positively with the passive lumbar extension test (PLE) (R = 0.32; p = 0.01) in the PRO group only. In summary, the results showed that the overall incidence of LSI was higher with severer disc damage. In addition, females were more prone to this pathology. However, the different types of LDH do not significantly affect the prevalence of LSI in young individuals.

Surgically managed symptomatic intraspinal lumbar facet synovial cyst outcome of surgical treatment with resection and instrumented posterolateral fusion, a case series

Background

There is controversy regarding the treatment of symptomatic synovial cysts, specifically, the need for a concomitant fusion when surgical resection of the synovial cysts is required. We present a retrospective review of a series of patients treated for symptomatic synovial cysts of the lumbar region during the last 20 years by a single surgeon, analyzing the current available literature.

Methods

Retrospective review. The same surgical technique was applied to all patients. Demographic, clinical, surgical data and synovial cyst recurrence rate were recorded. Postoperative results reported by patients were documented according to the McNab score.

Results

Sixty nine subjects, with mean follow-up of 7.4 years. 62% (43) were female, with a mean 57.8 years at the time of surgery. In 91.3% (63), the primary management was conservative for a minimum period of 3 months. All subjects underwent surgery due to the failure of conservative treatment. The segment most operated on was L4–L5 (63.77%). 91.3% (63) of the sample reported excellent and good and 6 subjects (8.6%) fair or poor results. There was no evidence of synovial cysts recurrence at the operated level.

Conclusion

In symptomatic synovial cysts, it seems that conservative treatment is only effective in a limited number of patients and in the short term. Thus, the recommendation of a surgical indication should proceed as soon as the conservative management fails to result in significant symptom relief. Based on our results, we recommend, together with the resection of the cyst, the instrumentation of the segment to avoid its recurrence and the management of axial pain.

Psoas muscle measurement as a predictor of recurrent lumbar disc herniation: A retrospective blind study

AbstractParaspinal (erector spinae and multifidus) and psoas muscles contribute to spinal stability, but no study has yet examined the relationship between muscle mass and recurrent lumbar disc herniation (rLDH). The purpose of this study was to investigate the effect of psoas and paraspinal muscle mass on recurrent Lumbar disc herniation (LDH). This retrospective study included 49 patients with LDH (22 men, 27 women; mean age: 59.9 years; range 32-80) who underwent discectomy and partial laminectomy without fusion and underwent both pre- and postoperative magnetic resonance imaging. The presence of rLDH was determined using medical records and postoperative magnetic resonance imagings. Patients were divided into an rLDH group (26 patients) and a without-rLDH group (23 patients). Clinical characteristics, segmental motion, and paraspinal and psoas muscle mass were compared between the groups. Using ImageJ software, the cross-sectional area (CSA), lean muscle mass (LMM), and skeletal muscle index (SMI) were measured on T2 axial preoperative magnetic resonance images at L2-L3, L3-L4, and L4-L5 disc levels to represent muscle mass. Univariate and multivariate logistic regression analyses were performed. In the rLDH group, patients were younger (52.6 years vs 68.2 years; P = .001), segmental instability was more common (50.0% vs 4.3%; P = .001), and the CSA, LMM, CSASMI, and LMMSMI of psoas muscles were larger (5851.59 mm2 vs 4264.93 mm2, 5456.59 mm2 vs 4044.77 mm2, 18.77 cm2/m2 vs 13.86 cm2/m2, and 17.52 cm2/m2 vs 12.98 cm2/m2; P < .01 for all 4 variables). On multivariate logistic regression, age and segmental instability were independent risk factors for rLDH (odds ratio 0.886 and 18.527; P = .01 and P = .02, respectively). In middle-aged and elderly patients with lumbar disc herniation, relatively younger age, segmental instability, and greater psoas muscle mass may be risk factors for recurrence.

Biomechanical evaluation of percutaneous cement discoplasty by finite element analysis

Background

Percutaneous cement discoplasty (PCD) is a minimally invasive treatment for degenerative lumbar spine disease, but the relationship between decompression effect on the nerve root and different doses of bone cement is uncertain.

Purpose

To investigate the indirect decompression effect of cement with different doses on nerve roots and the biomechanical changes on the spine during PCD using finite element analysis (FEA).

Methods

FEA was adapted to analyze the mechanical changes in the lumbar vertebrae before and after the application of PCD.CT scan images of adult males were utilized to establish a finite element model of the lumbar vertebral body using mimics and Pro/E software. The images were divided into four models: the normal model (normal, model N), the disc degeneration model (high, model H), the intervertebral disc injected with 3 mL of bone cement (model H1), and the intervertebral disc injected with 5 mL of bone cement (model H2). All models were analyzed using the ABAQUS6.14.2 software. The normal physiological movements were simulated, and the mechanical changes in the lumbar vertebrae were observed prior to and after the cement filling application.

Results

The stress of the nerve root in model H was the largest. The nerve root stress in the model H2 was the smallest during flexion, extension, left bending, right bending, left rotation, and right rotation at 90%, 44%, 25%, 56%, 56%, and 51% of the normal benchmark, respectively. After the injection of bone cement, the nerve root stress is reduced. The greater the amount of cement, the lesser the nerve root stress. The motion was reduced in models H, H1, and H2, and there were differences between models H1 and H2. Cartilage endplate stress was less in model H2 than in model H1.

Conclusions

The nerve root stress increased after degeneration and decreased after intervertebral height recovery through cement injection, resulting in a significant indirect decompression effect.The stress of the nerve root decreased with the increase in the amount of cement injection.

Intermodal Detection of Lumbar Instability in Degenerative Spondylolisthesis is Superior to Functional Radiographs

Purpose

In this study, we compare different imaging modalities to find the most sensitive and efficient way of detecting instability in lumbar spondylolisthesis.

Methods

Patients presenting with spondylolisthesis from June 01, 2018 to May 31, 2020 with functional radiographs and either CT scans or MRI images were included in our single-center retrospective cohort study. The amount of translation, in millimeters, was measured on supine MRI images, CT scans, and radiographs of inclination while sitting, standing, or prone and reclination while standing using the Meyerding technique. The amount of translation was compared among the different modalities.

Results

A total of 113 patients with spondylolisthesis on 125 vertebral levels were included in this study. The mean patient age was 73.52 ± 12.59 years; 69 (60.5%) patients were females. The most affected level was L4/5 (62.4%), followed by L3/4 (16%) and L5/S1 (13.6%). The average translations measured on supine CT were 4.13 ± 5.93 mm and 4.42 ± 3.49 mm on MRI (p = 0.3 for the difference between MRI and CT). The difference of inclination while sitting radiograph to slice imaging was 3.37 ± 3.64 mm (p < 0.0001), inclination while standing to slice imaging was 2.67 ± 3.03 mm (p < 0.0001), reclination while standing to slice imaging was 1.6 ± 3.15 mm (p = 0.03), and prone to slice imaging was 2.19 ± 3.02 mm (p = 0.03).

Conclusion

We found that a single radiograph in either inclination, reclination, or prone position compared to a CT scan or an MRI image in supine position can detect instability in spondylolisthesis more efficiently than comparison of functional radiographs in any position.

The effectiveness of percutaneous endoscopic decompression compared with open decompression and fusion for lumbar spinal stenosis: protocol for a multicenter, prospective, cohort study

Background

Lumbar spinal stenosis (LSS) is one of the most frequent indications for spine surgery. Open decompression and fusion surgery was the most common treatment and used to be regarded as the golden standard treatment for LSS. In recent years, percutaneous endoscopic decompression surgery was also used for LSS. However, the effectiveness and safety of percutaneous endoscopic decompression in the treatment of LSS have not been supported by high-level evidence. Our aim is to 1) compare the effectiveness of percutaneous endoscopic decompression surgery and open decompression and fusion for the treatment of LSS. 2) Investigate the prognosis risk factors for LSS. 3) Evaluate the influence of percutaneous endoscopic decompression for the stability of operative level, and degeneration of adjacent level.

Methods

It’s a prospective, multicenter cohort study. The study is performed at 4 centers in Beijing. This study plans to enroll 600 LSS patients (300 patients in the percutaneous endoscopic decompression group, and 300 patients in the open decompression and fusion group). The demographic variables, healthcare variables, symptom related variables, clinical assessment (Visual analogue score (VAS), Oswestry disability index (ODI), Japanese Orthopaedic Association score (JOA)), and radiological assessment (dynamic X-ray, CT, MRI) will be collected at baseline visit. Patients will follow up at 3, 6, 12 months. The primary outcome is the difference of improvement of ODI between baseline and 12-month follow-up between the two groups. The secondary outcome is the score changes of preoperative and postoperative VAS, the recovery rate of JOA, MacNab criteria, patient satisfaction, degeneration grade of adjacent level, ROM of operative level and adjacent level, complication rate.

Discussion

In this study, we propose to conduct a prospective registry study to address the major controversies of LSS decompression under percutaneous spinal endoscopy, and investigate the clinical efficacy and safety of percutaneous endoscopic decompression and open decompression in the treatment of LSS.

Trial registration

This study has been registered on clinicaltrials.gov in January 15, 2020 (NCT04254757). (SPIRIT 2a).

Circumferential Fusion Employing Transforaminal vs. Direct Lateral Lumbar Interbody Fusion—A Potential Impact on Implants Stability

Background

Different fusion techniques were introduced in clinical practice in patients with lumbar degenerative disc disease, however, no evidence has been provided on the advantages of one technique over another.

The Objective of This Study

Is to assess the potential impact of circumferential fusion employing transforaminal lumbar interbody fusion (TLIF) vs. direct lateral interbody fusion (DLIF) on pedicle screw stability.

Materials and Methods

This is a single-center prospective evaluation of consecutive 138 patients with degenerative instability of lumbar spinal segments. Either conventional transforaminal lumbar interbody fusion (TLIF) with posterior fusion or direct lateral interbody fusion (DLIF) using cages of standard dimensions, were applied. The conventional open technique was used to supplement TLIF with pedicle screws while percutaneous screw placement was used in patients treated with DLIF. The duration of the follow-up accounted for 24 months. Signs of pedicle screws loosening (PSL) and bone union after fusion were assessed by the results of CT imaging. Fisher‘s exact test was used to assess the differences in the rate of CT loosening and revision surgery because of implant instability. Logistic regression was used to assess the association between potential factors and complication rate.

Results

The rate of PSL detected by CT and relevant revision surgery in groups treated with TLIF and DLIF accounted for 25 (32.9%) vs. 2 (3.2%), respectively, for the former and 9 (12.0%) vs. 0 (0%) for the latter (p &lt; 0.0001 and p = 0.0043) respectively. According to the results of logistic regression, a decrease in radiodensity values and a greater number of levels fused were associated with a rise in PSL rate. DLIF application in patients with radiodensity below 140 HU was associated with a considerable decrease in complication rate. Unipolar or bipolar pseudoarthrosis in patients operated on with TLIF was associated with a rise in PSL rate while patients treated with DLIF tolerate delayed interbody fusion formation. In patients treated with TLIF supplementary total or partial posterior fusion resulted in a decline in PSL rate.

Conclusion

Even though the supplementary posterior fusion may considerably reduce the rate of PSL in patients treated with TLIF, the application of DLIF provide greater stability resulting in a substantial decline in PSL rate and relevant revision surgery.

Radiological Analysis of Minimally Invasive Microscopic Laminectomy for Lumbar Canal Stenosis with a Focus on Multilevel Stenosis and Spondylolisthesis

OBJECTIVE

We retrospectively compared the radiological and clinical outcomes of two different surgical techniques (lumbar spinous process splitting laminectomy [LSPSL] and unilateral laminotomy for bilateral decompression [ULBD]) to treat lumbar spinal canal stenosis (LCS).

METHODS

We performed a retrospective comparative study of 141 consecutive patients with an average age of 70.8 ± 9.4 years who had undergone LSPSL or ULBD for LCS between April 2015 and April 2019. None of the patients had developed remote fractures of the spinous processes using either technique. These cases were divided into 2 groups: group L, 73 patients who had undergone LSPSL from April 2015 to April 2017; and group U, 68 patients who had undergone ULBD from May 2017 to April 2019. The clinical and radiological outcomes and surgical complications at the 1-year postoperative follow-up period were evaluated.

RESULTS

We found no significant differences in the operative time between the 2 groups. However, group U had had significantly less blood loss than group L. The facet joints were significantly well preserved in group U. We examined the multilevel and spondylolisthesis cases separately and found that both surgical procedures were equally effective and that the visual analog scale scores for back or leg pain and Japanese Orthopaedic Association scores had significantly improved postoperatively in each group. Group U showed better outcomes in terms of LCS recurrence, with 3 patients in the group L requiring repeat surgery.

CONCLUSIONS

We found both ULBD and LSPSL to be safe and effective techniques for LCS, even for patients with spondylolisthesis and multilevel disease. ULBD was superior in terms of recurrence prevention, preservation of the facet joints, and less blood loss.

Combining clinical exams can better predict lumbar spine radiographic instability

BACKGROUND/OBJECTIVES

Several clinical tests have been proposed to diagnose lumbar instability, but their accuracy is still in question. The primary purpose of this study was to evaluate the diagnostic accuracy of the clinical lumbar instability tests. The secondary goal was to design a model to detect lumbar instability.

DESIGN

A prospective diagnostic cross-sectional study.

METHOD

A sample of 202 patients with chronic low back pain were participated in the study. Five lumbar instability tests including Aberrant movement, Passive lumbar extension, Prone segmental instability, H and I and pheasant tests were compared to flexion/extension radiography as the gold standard for diagnosing lumbar instability using two by two tables. Multiple Logistic Regression analysis was applied to develop a model using demographic information as well as the patients' pain intensity, disability level, lumbar lordosis and the clinical tests.

RESULTS

Among the five examined tests, Prone segmental instability, H and I and pheasant tests showed very small likelihood ratios and diagnostic odd's ratio. The largest values were for H and I test with the positive likelihood ratio of 1.28 (95% CI: 0.72 to 2.29) and diagnostic odd's ratio of 1.37 (95% CI: 0.66 to 2.83); the diagnostic accuracy measures were smaller for the other studied clinical tests. The model was developed using weight (t = 1.15, p = 0.03) and lumbar lordosis (t = 3.04, p = 0.00) (which showed a significant relationship with lumbar instability) and prone segmental instability test. The final model has the positive likelihood ratio of 2.07 (95% CI: 1.41 to 3.05) and diagnostic odd's ratio of 3.77 (95% CI: 2.03 to 7.01).

CONCLUSION

Each individual test had very small to no power in discriminating patients with lumbar instability. The developed model just slightly improved the accuracy of radiological instability detection.

A High Body Mass Index and the Vacuum Phenomenon Upregulate Pain-Related Molecules in Human Degenerated Intervertebral Discs

Animal studies suggest that pain-related-molecule upregulation in degenerated intervertebral discs (IVDs) potentially leads to low back pain (LBP). We hypothesized that IVD mechanical stress and axial loading contribute to discogenic LBP’s pathomechanism. This study aimed to elucidate the relationships among the clinical findings, radiographical findings, and pain-related-molecule expression in human degenerated IVDs. We harvested degenerated-IVD samples from 35 patients during spinal interbody fusion surgery. Pain-related molecules including tumor necrosis factor alpha (TNF-alpha), interleukin (IL)-6, calcitonin gene-related peptide (CGRP), microsomal prostaglandin E synthase-1 (mPGES1), and nerve growth factor (NGF) were determined. We also recorded preoperative clinical findings including body mass index (BMI), Oswestry Disability Index (ODI), and radiographical findings including the vacuum phenomenon (VP) and spinal instability. Furthermore, we compared pain-related-molecule expression between the VP (−) and (+) groups. BMI was significantly correlated with the ODI, CGRP, and mPGES-1 levels. In the VP (+) group, mPGES-1 levels were significantly higher than in the VP (−) group. Additionally, CGRP and mPGES-1 were significantly correlated. Axial loading and mechanical stress correlated with CGRP and mPGES-1 expression and not with inflammatory cytokine or NGF expression. Therefore, axial loading and mechanical stress upregulate CGRP and mPGES-1 in human degenerated IVDs, potentially leading to chronic discogenic LBP.

PERCUTANEOUS CEMENT DISCOPLASTY IN THE TREATMENT OF DEGENERATIVE DISC DISEASE. CASE SERIES

ABSTRACT Introduction: Percutaneous cement discoplasty (PCD) is a minimally invasive surgical technique, which provides segmental stabilization and an indirect decompression effect in cases of severe degenerative disc disease with vacuum phenomenon, useful in patients with comorbidities that contraindicate invasive surgical procedures. Materials and methods: A retrospective analysis of 6 patients undergoing PCD was carried out, reporting the demographic variables, the segments treated and the clinical result evaluated by means of the visual analog pain scale (VAS) both in the presurgical and in the 6-month follow-up. Finally, a literature review was carried out. Results: 6 cases of PCD were included, of which 5 had a diagnosis of dyscarthrosis and 1 dyscarthrosis with spondylolisthesis. 4 female and 2 male patients. In 3 patients, PCD was performed in 1 segment and in 3 patients in multiple segments. Regarding the clinical result, an improvement was presented in 5 of the patients (mean 5.6 VAS points), 1 of the patients did not present improvement and required another surgical intervention. Conclusions: PCD is a minimally invasive technique useful in the treatment of spine pain secondary to degenerative disc disease in those patients with comorbidities that contraindicate a major procedure. Indirect foraminal decompression by PCD in one or more segments appears to contribute to pain relief. Level of Evidence III. Series of cases and controls.

Associations between facet tropism and vertebral rotation in patients with degenerative lumbar disease

Background

Vertebral rotation and facet tropism are very common in various lumbar degenerative diseases. Facet tropism means the presence of asymmetric angles on both sides of the facet joints. Studies have shown that facet tropism contributes to lumbar degenerative disease, and also inevitably leads to the asymmetry of movement and the imbalance of force, which may be possible to rotate the vertebral body. The aim of this study was to explore the correlation between lumbar vertebral rotation and facet tropism in patients with lumbar degenerative diseases.

Methods

A total of 198 patients with lumbar degenerative diseases from 2018 to 2019 were enrolled. Five hundred and seventy vertebral rotation angles and 1140 facet angles were measured. The vertebral bodies are divided into non-rotation group (Group A) and rotation group (Group B) with the vertebral rotation angle of 3° as the boundary. The information including gender, age, BMI (body mass index), bone mineral density, history of smoking, drinking, hypertension, diabetes, diagnosis, segment distribution, and degree of facet degeneration were also counted. Using inter-class correlation coefficients (ICC) to test the reliability of measurement results. Univariate and multivariate logistic regression analysis were used to analyze the relationship between vertebral rotation and facet tropism.

Results

The consistency of the ICC within the groups of the observers is above 0.8, with good agreement. The results of univariate analysis showed that facet tropism was significantly different between group A and group B (OR (odds ratio)  = 3.30, 95% CI  =  2.03–5.35, P  < 0.0001). Other significant factors were included as adjustment variables into the multivariate regression model. Three models were analyzed separately (Model 1: non-adjusted. Model 2: adjust for age; facet degeneration; Model 3: adjust for age; disease distribution; segment distribution; facet degeneration). The results showed that after adjusting the confounders, the correlation between facet tropism and vertebral rotation did not change (Model 1: OR  = 3.30, 95% CI  = 2.03–5.35, P  < 0.0001; Model 2: adjusted OR  = 2.87, 95% CI  = 1.66–4.97, P  = 0.0002, Model 3: adjusted OR  = 2.84, 95% CI  = 1.56–5.17, P  = 0.0006).

Conclusion

Current research demonstrates that there is an association between vertebral rotation and facet tropism, suggesting that vertebral rotation may also have a certain degree of correlation with lumbar degenerative diseases.

The Morphological Changes in Adjacent Segments Amongst Patients Receiving Anterior and Oblique Lumbar Interbody Fusion: A Retrospective Study

Adjacent segment disease (ASD) is troublesome condition that has proved to be highly related to spinal malalignment after spinal surgery. Hence, we aimed to evaluate the morphological changes after anterior lumbar interbody fusion (ALIF) and oblique LIF (OLIF) to establish the differences between the two surgical methods in terms of possible ASD avoidance. Fifty patients, half of whom received ALIF while the other half received OLIF, were analyzed with image studies and functional outcomes during the pre-operative and post-operative periods, and 2 years after surgery. Image measurements obtained included spinal-pelvic parameters, index lordosis (IL), segmental lordosis (SL), anterior disc height (ADH), posterior disc height (PDH) and adjacent segment disc angle (ASDA). The ADH and PDH in the adjacent segment decreased in the two groups while OLIF showed greater decrease without radiological ASD noted at 2-year follow-up. Both groups showed an increase in IL after surgery while ALIF showed greater improvement. No statistical difference was identified in functional outcomes between LIFs. We suggest that both ALIF and OLIF can restore adequate lordosis and prevent ASD after surgery. However, it should be noted that patient selection remains crucial when making any decision involving which of the two methods to use.

A diagnostic tool for people with lumbar instability: a criterion-related validity study

BACKGROUND

Several clinical tests used to identify patients with lumbar instability have reported diagnostic accuracy in separate studies with conflicting results. To augment the diagnostic process, tests that are better able to identify lumbar instability suitable for use in the clinical setting are required. The aim of this study was to identify the probability to diagnose patients with lumbar instability, using x-ray imaging as the reference standard.

METHODS

This study was a cross-sectional, diagnostic validity study. One hundred forty participants with chronic low back pain underwent an x-ray assessment and 14 clinical examinations. Data were analysed using multivariate regression methods to determine which clinical tests were most diagnostic for lumbar instability when they were applied together.

RESULTS

Eighteen (12.85%) participants had radiological lumbar instability. Three clinical tests i) interspinous gap change during flexion-extension, ii) passive accessory intervertebral movement tests, iii) posterior shear test demonstrated an ability to diagnose lumbar instability of 67% when they were all positive. At this probability threshold, sensitivity, specificity, positive likelihood ratio (+LR), and negative likelihood ratio (-LR) were 5.56, 99.18%, 6.78, and 0.95.

CONCLUSIONS

These 3 clinical tests could be useful in identifying patients with lumbar instability in the general community. These three tests are simple to perform by physical therapists, reliable to use in a clinical setting, and safe for patients. We recommend physical therapists use these three tests to assess patients who are suspected of having lumbar instability, in the absence of an x-ray assessment, to receive appropriate targeted intervention or referral for further investigation.

TRIAL REGISTRATION

Thai Clinial Trial Registry (TCTR 20180820001; 19th August 2018).

Validity of a Screening Tool for Patients with a Sub-Threshold Level of Lumbar Instability: A Cross-Sectional Study

Lumbar instability (LI) comprises one subgroup of those with chronic low back pain (CLBP); it indicates the impairment of at least one of the spinal stabilizing systems, and radiographic criteria of translation and rotation are used for its diagnosis. Previous studies have developed and tested a screening tool for LI where patients with sub-threshold lumbar instability (STLI) were detected in the initial stage of lumbar pathology using radiographs as a gold standard for diagnosis. The radiographic measurement in STLI lies between the range of translation and rotation of the LI and asymptomatic lumbar motion. However, there are no studies indicating the validity and cut-off points of the screening tool for STLI. The current study aimed to determine the validity of an LI screening tool to support the diagnostic process in patients with STLI. This study design was cross-sectional in nature. A total of 135 participants with CLBP, aged between 20 and 60 years, who had undergone flexion and extension radiographs, answered a screening tool with 14 questions. The cut-off score for identifying STLI using the screening tool was at least 6/14 positive responses to the LI questions. The findings suggested that the LI screening tool we tested is effective for the detection of STLI. The tool can be used in outpatient settings.

Long-Term Outcome After Midline Lumbar Fusion for the Treatment of Lumbar Spine Instability Due to Degenerative Disease

BACKGROUND

Midline lumbar fusion (MIDLF) is one promising new surgical technique that has been developed to minimize perioperative damage to the paravertebral stabilizing musculotendinous system. The aim of this study was to assess long-term clinical and radiological effects of MIDLF.

METHODS

This prospective cohort study evaluated patients who underwent MIDLF for degenerative spinal instability. Clinical and radiological examinations were performed before and after surgery. Perioperative and postoperative complications were recorded. Follow-up was 2 years. P ≤ 0.05 was considered statistically significant.

RESULTS

The study included 64 patients (mean age 58.9 ± 10.7 years; 41 women [64.1%]). The most frequent indication for MIDLF was degenerative spondylolisthesis grade I (28 cases [43.8%]); the prevalent spinal segment to be fused was L4-L5 (35 cases [54.7%]). Mean duration of surgery was 148.2 ± 28.9 minutes. Relief of low back pain and leg pain was significant and stable in the postoperative period as assessed by visual analog scale (P < 0.001). Of patients, 86.9% reported fair, good, or excellent outcomes in terms of pain relief based on MacNab score 2 years after surgery. Patients' level of function in activities of daily living improved significantly based on Oswestry Disability Index score: from 66.8 ± 9.8 before surgery to 33.9 ± 16.5 2 years after surgery (P < 0.001). X-rays and computed tomography at 12 months showed interbody fusion in 46 cases (73.4%), inconclusive results in 13 cases (20.3%), and no fusion in 4 cases (6.3%). No damage to neural or vascular structures and no failure of hardware or screw loosening were recorded.

CONCLUSIONS

MIDLF is a safe, efficient method for surgical treatment of lumbar spine instability. Its limited invasiveness contributes to better preservation of paravertebral muscles and enhanced postoperative spinal stability.

The Results of Using a Transforaminal Lumbar Interbody Fusion Cage at the Upper Lumbar Level

Aim

The aim of this study is to apply surgical treatments to upper lumbar disc hernias in order to provide lumbar stability and lumbar lordosis using a transforaminal lumbar interbody fusion (TLIF) cage and to preserve the success rate of surgical results by protecting neural structures without excessive subject tension.

Material and methods

Between 2012 and 2017, 32 patients who had undergone an operation for upper lumbar disc herniation and who had received a transforaminal lumbar interbody fusion cage using a posterior technique were evaluated retrospectively.

Results

The radiological and clinical findings, surgical methods, and results of the patients were evaluated. In our study, 25 (78.1%) of the patients with upper lumbar disc hernias who were evaluated retrospectively were female and seven (21.9%) were male. Their average age was 55.43 years. The average follow-up was 21.75 months. The most common complaints were lower back pain, leg pain, and claudication. In the findings from neurological examinations, a positive result on the femoral stretching test occurred in 30 (93.7%) patients. In the degenerative spinal structure of patients at the L1-2 and L2-3 levels, a transforaminal lumbar interbody fusion was performed via a wide laminectomy with posterior stabilization due to a wide-bottomed disc hernia and stenosis. Only one of the patients with a neurological deficit still had a motor deficit after surgery.

Conclusion

While planning a surgery for upper lumbar disc hernias, the anatomical features of this region and the patients' radiological and neurological findings should be carefully evaluated. If TLIF is performed during upper lumbar region surgery, it may be preferable to perform it using a posterior technique.

Full-Endoscopic Lumbar Decompression versus Open Decompression and Fusion Surgery for the Lumbar Spinal Stenosis: A 3-Year Follow-Up Study

Purpose

Compare the efficacy of full-endoscopic lumbar decompression surgery (FELDS) and open decompression and fusion surgery (ODFS) for lumbar spinal stenosis (LSS).

Patients and Methods

A retrospective analysis of 358 LSS patients treated by FELDS (“FELD” group) or ODFS (“open” group) was undertaken. There were 177 patients in the FELDS group with a mean age of 65.47±9.26 years and 181 patients in the open group with a mean age of 64.18±10.24 years. Duration of follow-up was 38.63±11.88 months in the FELDS group and 38.56±12.29 months in the open group. Visual analog scale (VAS) score, Oswestry Disability Index (ODI), and Modified MacNab criteria were used to access clinical outcomes. Surgical outcomes (duration of surgical procedure, blood loss, complications, duration of postoperative hospital stay (DOPHS), prevalence of revision procedures) were evaluated. Magnetic resonance imaging was used to evaluate the change in the Pfirrmann grade at adjacent segments.

Results

VAS score (leg and back) and ODI improved significantly in both groups (P<0.001). Success rate reached 86.55% and 90.60% in the FELDS group and open group (P>0.05), respectively. Procedure duration (84.12 vs 112.08 min), blood loss (7.97 vs 279.67 mL), and DOPHS (2.68 vs 4.78 days) of the FELDS group were significantly better than those of the open group (P<0.05). Total prevalence of complications and procedure revisions was 14.69% and 10.73% in the FELD group, respectively, but did not show a significant difference with that in the open group (12.15% and 9.39%, respectively). The Pfirrmann grade increased in 13.04% of adjacent segments in the FELDS group, significantly better than that in the open group (32.67%) (P<0.05).

Conclusion

FELDS had the same efficacy as ODFS for LSS treatment. FELDS had the advantages of minimal invasiveness, less surgical trauma, rapid recovery, and lower risk of degeneration of adjacent segments compared with that of ODFS.

Potential contribution of pedicle screw design to loosening rate in patients with degenerative diseases of the lumbar spine: An observational study

BACKGROUND

The majority of published data report the results of biomechanical tests of various design pedicle screw performance. The clinical relevance and relative contribution of screw design to instrumentation stability have been insufficiently studied.

AIM

To estimate the contribution of screw design to rate of pedicle screw loosening in patients with degenerative diseases of the lumbar spine.

METHODS

This study is a prospective evaluation of 175 patients with degenerative diseases and instability of the lumbar spine segments. Participants underwent spinal instrumentation employing pedicle screws with posterior only or transforaminal interbody fusion. Follow-up was for 18 mo. Patients with signs of pedicle screw loosening on computed tomography were registered; logistic regression analysis was used to identify the factors that influenced the rate of loosening.

RESULTS

Parameters included in the analysis were screw geometry, type of thread, external and internal screw diameter and helical pitch, bone density in Hounsfield units, number of levels fused, instrumentation without anterior support, laminectomy, and unilateral and bilateral total facet joint resection. The rate of screw loosening decreased with the increment in outer diameter, decrease in core diameter and helical pitch. The rate of screw loosening correlated positively with the number of fused levels and decreasing bone density. Bilateral facet joint removal significantly favored pedicle screw loosening. The influence of other factors was insignificant.

CONCLUSION

Screw parameters had a significant impact on the loosening rate along with bone quality characteristics, the number of levels fused and the extensiveness of decompression. The significance of the influence of screw parameters was comparable to those of patient- and surgery-related factors. Pedicle screw loosening was influenced by helical pitch, inner and outer diameter, but screw geometry and thread type were insignificant factors.

Mobilisation efficacy in young patients with different stages of degenerative disc disease

BACKGROUND

Lumbar vertebrae carry the greatest load from the spinal column, often leading to several pathologies, including degenerative disc disease (DDD), potentially disturbing spinal movement patterns. Mobilisation increases hypomobile segment mobility, however there is little evidence on mobilisation in patients suffering from different types of DDD.

OBJECTIVE

To assess the efficacy of mobilisation in young patients with DDD, as diagnosed by MRI.

METHODS

Thirty patients (24-35 years) participated in this study, and were divided into two groups, based on progression levels of DDD diagnosed by MRI (protrusion-PRO/extrusion-EXT). Twenty sessions of sustained stretch mobilisation (grade III) were applied to both groups over four weeks. Numeric Rating Scale (NRS), Oswestry Disability Index (ODI), straight leg raise (SLR), passive lumbar extension (PLE) and lumbar range of motion (ROM) assessed outcome variables. Three trial stages were investigated: pre-therapy (1), post-therapy (2) and follow-up (3).

RESULTS

Age (p= 0.007) and NRS (p= 0.002) were significantly different before therapy. Patient outcomes were significantly improved for all parameters in both groups, except SLR which improved in the EXT group only (p= 0.043).

CONCLUSIONS

Applied treatments improved patient outcomes and were statistically significant in both groups, however, better outcomes were observed in the EXT group during follow-up. Mobilisation was a safe and effective procedure for the treatment of DDD.

Novel model of restricted mobility induced osteopenia in zebrafish

Immobilization, such as prolonged bed rest, is a risk factor for bone loss in humans. Motivated by the emerging utility of zebrafish (Danio rerio) as an animal of choice for the study of musculoskeletal disease, here we report a model of restricted mobility induced osteopenia in adult zebrafish. Aquatic tanks with small cubical compartments to restrict the movement and locomotion of single fish were designed and fabricated for this study. Adult zebrafish were divided into two groups: a normal control (CONT) and a restricted mobility group (RMG) (18 fish/group). Six fish from each group were euthanized on days 14, 21 and 35 of the movement restriction. By using microcomputed tomography (micro-CT), we assessed bone volume/tissue volume (BV/TV) and bone density in the whole skeleton of the fish. Furthermore, we assessed skeletal shape in the vertebrae (radius, length, volume, neural and haemal arch aperture areas, neural and haemal arch angle, and thickness of the intervertebral space), single vertebra bone volume and bone density. Movement restriction significantly decreased vertebral skeletal parameters such as radius, length, volume, arch aperture areas and angles as well as the thickness of the intervertebral space in RMG. Furthermore, restricted mobility significantly (P < 0.001) decreased BV/TV and bone density as compared to the CONT group, starting as early as 14 days. By analysing zebrafish from CONT and RMG, we show that micro-CT imaging is a sensitive method to quantify distinct skeletal properties in zebrafish. We further defined the micro-CT parameters which can be used to examine the effects of restricted mobility on the skeleton of the fish. Our findings propose a rapid and effective osteopenia "stabulation" model, which could be used widely for osteoporosis drug screening.