Biomechanical In Vitro and Finite Element Study on Different Sagittal Alignment Postures of the Lumbar Spine During Multiaxial Daily Motion.

Lumbar lordotic correction (LLC), the gold standard treatment for sagittal spinal malalignment (SMA), and its effect on sagittal balance have been critically discussed in recent studies. This paper assesses the biomechanical response of the spinal components to LLC as an additional factor for the evaluation of LLC. Human lumbar spines (L2L5) were loaded with combined bending moments in flexion (Flex)/extension (Ex) or lateral bending (LatBend) and axial rotation (AxRot) in a physiological environment. We examined the dependency of AxRot range of motion (RoM) on the applied bending moment. The results were used to validate a finite element (FE) model of the lumbar spine. With this model, the biomechanical response of the intervertebral discs (IVD) and facet joints under daily motion was studied for different sagittal alignment postures, simulated by a motion in Flex/Ex direction. Applied bending moments decreased AxRot RoM significantly (all P < 0.001). A stronger decline of AxRot RoM for Ex than for Flex direction was observed (all P < 0.0001). Our simulated results largely agreed with the experimental data (all R2 > 0.79). During the daily motion, the IVD was loaded higher with increasing lumbar lordosis (LL) for all evaluated values at L2L3 and L3L4 and posterior annulus stress (AS) at L4L5 (all P < 0.0476). The results of this study indicate that LLC with large extensions of LL may not always be advantageous regarding the biomechanical loading of the IVD. This finding may be used to improve the planning process of LLC treatments.

Quality of life and mortality after surgical treatment for vertebral osteomyelitis (VO): a prospective study.

PURPOSE: Vertebral osteomyelitis (VO) has a high mortality and leads to chronic pain and functional disability. Surgical treatment is often necessary. To date, little is known about the consequences of surgery on patient outcome. The aim of this study was to determine the quality of life (QoL) and mortality rates of surgically treated VO patients for a period of 2 years. METHODS: Patients with VO undergoing surgical treatment in a tertiary referral hospital from 2008 to 2015 were included prospectively. Data were collected before (T0) as well as 1 year (T1) and 2 years (T2) post-surgery. Within the European Spine Tango registry, prospective patient and QoL data were collected using validated outcome scores: Oswestry Disability Index, Short Form 36/EuroQol, Visual Analog Scale, and Core Outcome Measures Index. RESULTS: From 195 patients surgically treated for VO, QoL data were available from 136 patients at T0, 100 patients at T1, and 82 patients at T2, respectively. The 1- and 2-year mortality rates were 20% and 23%. Mainly all QoL outcome scores showed significant improvement at T1 and did not change significantly from T1 to T2. CONCLUSION: Surgical treatment of VO patients leads to significantly improved QoL. Nevertheless, QoL levels were below those of the general population. Our results underscore that spine disability questionnaires measuring QoL are mandatory to demonstrate comprehensively the severity of this entity. Our study confirms a high mortality and points out the role of VO as a potentially life-threatening condition.

Biomechanical In Vitro Test of a Novel Dynamic Spinal Stabilization System Incorporating Polycarbonate Urethane Material Under Physiological Conditions.

Posterior dynamic stabilization systems (PDSS) were developed to provide stabilization to pathologic or hypermobile spinal segments while maintaining the healthy biomechanics of the spine. Numerous novel dynamic devices incorporate the temperature and moisture dependent material polycarbonate urethane (PCU) due to its mechanical properties and biocompatibility. In this study, standardized pure moment in vitro tests were carried out on human lumbar spines to evaluate the performance of a device containing PCU. An environmental chamber with controlled moisture and temperature was included in the setup to meet the requirements of testing under physiological conditions. Three test conditions were compared: (1) native spine, (2) dynamic instrumentation, and (3) dynamic instrumentation with decompression. The ranges of motion, centers of rotation, and relative pedicle screw motions were evaluated. The device displayed significant stiffening in flexion-extension, lateral bending, and axial rotation load directions. A reduction of the native range of motion diminished the stiffening effect along the spinal column and has the potential to reduce the risk of the onset of degeneration of an adjacent segment. In combination with decompression, the implant decreased the native range of motion for flexion-extension and skew bending, but not for lateral bending and axial rotation. Curve fittings using the sigmoid function were performed to parameterize all load-deflection curves in order to enhance accurate numerical model calibrations and comparisons. The device caused a shift of the center of rotation (COR) in the posterior and caudal direction during flexion-extension loading.

Material failure in dynamic spine implants: are the standardized implant tests before market launch sufficient?

PURPOSE: International Standards Organization (ISO) 12189 and American Society for Testing and Materials F2624 are two standard material specification and test methods for spinal implant devices. The aim of this study was to assess whether the existing and required tests before market launch are sufficient. METHODS: In three prospective studies, patients were treated due to degenerative disease of the lumbar spine or spondylolisthesis with lumbar interbody fusion and dynamic stabilization of the cranial adjacent level. The CD HORIZON BalanC rod and S4 Dynamic rod were implanted in 45 and 11 patients, respectively. RESULTS: A fatigue fracture of the material of the topping off system has been found in five cases (11%) for the group fitted with the CD HORIZON BalanC rod. In the group using the S4 Dynamic rod group, a material failure of the dynamic part was demonstrated in seven patients (64%). All three studies were interrupted due to these results, and a report to the Federal Institute for Drugs and Medical Devices was generated. CONCLUSION: Spinal implants have to be checked by a notified body before market launch. The notified body verifies whether the implants fulfil the requirements of the current standards. These declared studies suggest that the current standards for the testing of load bearing capacity and stand ability of dynamic spine implants might be insufficient. Revised standards depicting sufficient deformation and load pattern have to be developed and counted as a requirement for the market launch of an implant. These slides can be retrieved under Electronic Supplementary Material.

The use of the DTO™ hybrid dynamic device: a clinical outcome- and radiological-based prospective clinical trial.

BACKGROUND: The purpose of this study was to assess the radiological and clinical outcome parameters following lumbar hybrid dynamic instrumentation with the focus on the adjacent segment degeneration (ASD) and adjacent segment disease (ASDi). METHODS: In this prospective trial all patients presenting with degenerative changes to the lumbar spine have been included. Precondition was a stable adjacent level with/without degenerative alteration. The elected patients underwent a standardised fusion procedure with hybrid instrumentation (DTO™, Zimmer Spine Inc., Denver, USA). Patients' demographics have been documented and the follow-up visits were conducted after 6 weeks, and then stepwise after 6 up to 48 months. Each follow-up visit included assessment of quality of life and pain using specific questionnaires (COMI, SF-36, ODI) and the radiological evaluation with focus on the adjacent level alterations. RESULTS: At a mean follow up of 24 months an incidence of ASD with 10.91% and for ASDi with 18.18% has been observed. In 9% a conversion to standardised fusion was needed. There was a high rate of mechanical complication: (1) screw loosening (52.73%), (2) pedicle screw breakage (10.91%), and (3) rod breakage (3.64%) after a follow up of a maximum of 60 months. There were no significant difference of COMI, ODI and SF-36(v2) in comparison to all groups but all 55 patients showed a clinical improvement over the time. CONCLUSION: The dynamic hybrid DTO™ device is comparable to the long-term results after standardised fusion procedure, while a high rate of mechanical complication decreased the initial benefit. TRIAL REGISTRATION: This trial was registered at the ClinicalTrials Register ( #NCT03404232 , 2018/01/18, registered retrospectively).

Predictors of improvement in quality of life and pain relief in lumbar spinal stenosis relative to patient age: a study based on the Spine Tango registry.

BACKGROUND: An open decompression is the most common treatment for lumbar spinal canal stenosis (LSS), even in the elderly. However, it is not clear whether the treatment outcome is age dependent. The main purpose of this study was to evaluate the improvement in quality of life (QoL) and pain relief, after open decompression for LSS in relation to patient age. METHODS: The study was performed on the basis of Spine Tango registry data. The database query resulted in 4768 patients from 40 international Spine Tango centres. The patients were subdivided into three age groups: (1) 20-64, (2) 65-74, and (3) ≥75 years. In multivariate logistic regression models, predictors for improvement in QoL and achievement of the minimum clinically relevant change in pain of two points were analysed. RESULTS: All groups benefited from significant improvement in QoL and back and leg pain relief. Age group had no significant influence on the outcomes. The preoperative status of each outcome was a predictor for its own postoperative outcome. Fewer previous surgeries, rigid or dynamic stabilization, and lower patient comorbidity also had a partially predictive influence for one or the other outcome. CONCLUSIONS: Our results confirm that all age groups significantly benefit from the open decompressive treatment of LSS. Age group had no significant influence on any outcome.

Is the duration of pre-operative conservative treatment associated with the clinical outcome following surgical decompression for lumbar spinal stenosis? A study based on the Spine Tango Registry.

BACKGROUND: The incidence of lumbar spinal stenosis (LSS) continues to rise, with both conservative and surgical management representing options for its treatment. The timing of surgery for LSS varies from shortly after the onset of symptoms to several months or years after conservative treatment. The aim of this study was to investigate the association between the duration of pre-operative conservative treatment and the ultimate outcome following surgical interventions for LSS. METHODS: The study was based on prospective multicentre registry data (Spine Tango). Cases of LSS with a documented duration of conservative treatment, undergoing spinal decompression with at least one post-operative patient assessment between 3 and 30 months, were included in the study. Cases of LSS with spondylolisthesis, additional spinal pathology or previous spinal surgery were excluded. Interrogation of the Spine Tango Registry listed 3478 patients meeting the prescribed inclusion criteria. This cohort was stratified into four groups: (1) no previous treatment (n = 497; 14.3%), (2) conservative treatment <6 months (n = 965; 27.8%), (3) conservative treatment between 6 and 12 months (n = 758; 21.8%), and (4) conservative treatment >12 months (n = 1258; 36.1%). Group 4 reference group in regression analysis. The inverse probability of treatment weighting (IPTW) was applied using the propensity score to balance the groups for their characteristics. Outcome measures included achievement of the minimum clinically important change (MCIC) score of 2 points for (a) back pain, (b) leg pain and (c) Core Outcome Measures Index (COMI), and (d) surgical complications, (e) general complications and (f) operation time >2 h. RESULTS: Patient group ("duration of conservative therapy") was not associated with achievement of the MCIC for post-operative relief of leg pain (p = 0.22), achievement of MCIC for the COMI score (p = 0.054), surgical complications (p = 0.11) or general complications (p = 0.14). Only MCIC for post-operative relief of back pain (p = 0.021) and operation time were significantly associated with patient group (p = 0.038). However, compared with the reference group of >12 months of conservative treatment there was no significant difference in the likelihood of achieving the MCIC for those with none, <6 or 6-12 months of conservative treatment. CONCLUSIONS: The duration of pre-operative conservative treatment was not associated with the ultimate outcome of decompression surgery. Further research is required to investigate optimal thresholds/indications for surgery and its appropriate timing in individual patients.

Incidental durotomy in decompression for lumbar spinal stenosis: incidence, risk factors and effect on outcomes in the Spine Tango registry.

PURPOSE: The three aims of this Spine Tango registry study of patients undergoing decompression for spinal stenosis were to: report the rate of dural tear (DT) stratified by treatment centre; find factors associated with an increased likelihood of incurring a DT; and compare treatment outcomes in relation to DT (none vs. repaired vs. unrepaired DT). METHODS: Multivariate logistic regression was used to assess the association between DT and patient and treatment characteristics. Patient-rated and surgical outcomes were compared in patients with no DT, repaired DT, and unrepaired DT, while adjusting for case-mix. RESULTS: DT occurred in 328/3254 (10.1%) of included patients. The rate for all 29 contributing hospitals was within 95% confidence intervals of the average. The likelihood of DT increased by 2% per year of age, 1.78 times with previous spine surgery, 1.67 for a minimally/less invasive surgery, 1.58 times with laminectomy, and 1.40, and 2.12 times for BMI 31-35, and >35 in comparison with BMI 26-30, respectively. The majority of DTs (272/328; 82.9%) were repaired. Repairing the DT was associated with a longer duration of surgery (p < 0.001). More patients with repaired than with unrepaired DTs were satisfied with treatment, but the difference was not statistically significant. There was no association between DT and patient-reported outcomes. CONCLUSION: The unadjusted rate of incidental DT during decompression for LSS was homogeneous across the participating centres and was associated with age, BMI, previous surgery at the same spinal level, minimally/less invasive surgery, and laminectomy. Non-repair of DTs had no negative association with treatment outcome; however, the unrepaired DTs may have been those that were smaller in size.

Plasmacytoid dendritic cells and memory T cells infiltrate true sequestrations stronger than subligamentous sequestrations: evidence from flow cytometric analysis of disc infiltrates.

PURPOSE: Herniated nucleus pulposus has been considered to induce an adaptive immune response. Antigen recognition by antigen-presenting-cells (APCs) represents an important step within manifestation of an adaptive immune response. Macrophages have been assumed to function as APC, while importance of plasmacytoid dendritic cells for initiation of an immune response directed towards herniated nucleus pulposus has never been examined. The aim of the present study was to assess importance of plasmacytoid dendritic cells for initiation of immune response directed towards herniated discs. METHODS: Fifteen patients with true sequestrations and three patients with subligamentous sequestrations underwent surgery after their neurological examinations. Disc material was harvested, weighted and digested for 90 min. Separated single cells were counted, stained for plasmacytoid dendritic cells (CD123(+)CD4(+)), macrophages (CD14(+)CD11c(+)) and memory T cells (CD4(+)CD45RO(+)) and analysed by flow cytometry. Both patient groups were compared in cell proportions. Furthermore, patients with true sequestrations (TRUE patients) were subdivided into subgroups based on severity of muscle weakness and results in straight leg raising (SLR) test. Subgroups were compared in cell proportions. RESULTS: Plasmacytoid dendritic cells and memory T cells infiltrated true sequestrations stronger than the subligamentous sequestration and plasmacytoid dendritic cells predominated over macrophages in true sequestrations. Highest proportions of plasmacytoid dendritic cells were detected in infiltrates of patients having true sequestrations, severe muscle weakness and negative result in SLR test. CONCLUSIONS: The findings of the present study indicate that plasmacytoid dendritic cells are involved in initiation of an immune response directed towards herniated nucleus pulposus, while macrophages may reinforce the manifested immune response and mediate disc resorption.

Patient outcomes after laminotomy, hemilaminectomy, laminectomy and laminectomy with instrumented fusion for spinal canal stenosis: a propensity score-based study from the Spine Tango registry.

PURPOSE: To compare patient outcomes and complication rates after different decompression techniques or instrumented fusion (IF) in lumbar spinal stenosis (LSS). METHODS: The multicentre study was based on Spine Tango data. Inclusion criteria were LSS with a posterior decompression and pre- and postoperative COMI assessment between 3 and 24 months. 1,176 cases were assigned to four groups: (1) laminotomy (n = 642), (2) hemilaminectomy (n = 196), (3) laminectomy (n = 230) and (4) laminectomy combined with an IF (n = 108). Clinical outcomes were achievement of minimum relevant change in COMI back and leg pain and COMI score (2.2 points), surgical and general complications, measures taken due to complications, and reintervention on the index level based on patient information. The inverse propensity score weighting method was used for adjustment. RESULTS: Laminotomy, hemilaminectomy and laminectomy were significantly less beneficial than laminectomy in combination with IF regarding leg pain (ORs with 95% CI 0.52, 0.34-0.81; 0.25, 0.15-0.41; 0.44, 0.27-0.72, respectively) and COMI score improvement (ORs with 95% CI 0.51, 0.33-0.81; 0.30, 0.18-0.51; 0.48, 0.29-0.79, respectively). However, the sole decompressions caused significantly fewer surgical (ORs with 95% CI 0.42, 0.26-0.69; 0.33, 0.17-0.63; 0.39, 0.21-0.71, respectively) and general complications (ORs with 95% CI 0.11, 0.04-0.29; 0.03, 0.003-0.41; 0.25, 0.09-0.71, respectively) than laminectomy in combination with IF. Accordingly, the likelihood of required measures was also significantly lower after laminotomy (OR 0.28, 95% CI 0.17-0.46), hemilaminectomy (OR 0.28, 95% CI 0.15-0.53) and after laminectomy (OR 0.39, 95% CI 0.22-0.68) in comparison with laminectomy with IF. The likelihood of a reintervention was not significantly different between the treatment groups. DISCUSSION: As already demonstrated in the literature, decompression in patients with LSS is a very effective treatment. Despite better patient outcomes after laminectomy in combination with IF, caution is advised due to higher rates of surgical and general complications and consequent required measures. Based on the current study, laminotomy or laminectomy, rather than hemilaminectomy, is recommendable for minimum relevant pain relief.

Evaluation of efficacy of a new hybrid fusion device: a randomized, two-centre controlled trial.

BACKGROUND: The 360° fusion of lumbar segments is a common and well-researched therapy to treat various diseases of the spine. But it changes the biomechanics of the spine and may cause adjacent segment disease (ASD). Among the many techniques developed to avoid this complication, one appears promising. It combines a rigid fusion with a flexible pedicle screw system (hybrid instrumentation, "topping off"). However, its clinical significance is still uncertain due to the lack of conclusive data. METHODS/DESIGN: The study is a randomized, therapy-controlled, two-centre trial conducted in a clinical setting at two university hospitals. If they meet the criteria, outpatients presenting with degenerative disc disease, facet joint arthrosis or spondylolisthesis will be included in the study and randomized into two groups: a control group undergoing conventional fusion surgery (PLIF - posterior lumbar intervertebral fusion), and an intervention group undergoing fusion surgery using a new flexible pedicle screw system (PLIF + "topping off"), which was brought on the market in 2013. Follow-up examination will take place immediately after surgery, after 6 weeks and after 6, 12, 24 and 36 months. An ongoing assessment will be performed every year.Outcome measurements will include quality of life and pain assessments using validated questionnaires (ODI - Ostwestry Disability Index, SF-36™ - Short Form Health Survey 36, COMI - Core Outcome Measure Index). In addition, clinical and radiologic ASD, sagittal balance parameters and duration of work disability will be assessed. Inpatient and 6-month mortality, surgery-related data (e.g., intraoperative complications, blood loss, length of incision, surgical duration), postoperative complications (e.g. implant failure), adverse events, and serious adverse events will be monitored and documented throughout the study. DISCUSSION: New hybrid "topping off" systems might improve the outcome of lumbar spine fusion. But to date, there is a serious lack of and a great need of convincing data on safety or efficacy, including benefits and harms to the patients, of these systems. Health care providers are particularly interested in such data as these implants are much more expensive than conventional implants. In such a case, randomized clinical trials are the best way to evaluate benefits and risks. TRIAL REGISTRATION: NCT01852526.

[Slipped vertebrae (Spondylolysis): the underestimated weak point of the (pre)professional football player-an algorithm]. / Der Gleitwirbel: unterschätzte Schwachstelle des (prä)professionellen Fußballspielers ­ ein Algorithmus.

BACKGROUND: Isthmic spondylolysis represents the most common cause of spinal pain in adolescent athletes. This article provides an overview of the classification, diagnosis, and treatment options for these conditions, including conservative and operative measures. It also provides a treatment pathway to how young athletes with spondylolysis should be treated. DIAGNOSTICS: Diagnostic imaging techniques are essential for an accurate diagnosis, with CT scans providing additional information for surgical planning. TREATMENT: Conservative treatment focuses on activity modification and physiotherapy, with a phased approach tailored to individual patient needs. Operative intervention may be considered if conservative measures fail, with minimally invasive techniques such as Buck's screw fixation showing promising results. The decision between conservative and operative management should consider factors of the patients' individual profile. In this paper, we present the first treatment algorithm for the treatment of isthmic spondylolysis. Long-term prognosis varies, with most athletes able to return to sport following treatment.

Brain structural and psychometric alterations in chronic low back pain.

PURPOSE: Chronic low back pain (CLBP) is one of the most important pain disorders with increasing social and economic implications. Given that CLBP is a multidimensional process associated with comorbidities such as anxiety and depression, treatment of chronic low back pain is still a challenge. Advancement of in vivo brain imaging technologies has revealed increasing insights into the etiology and pathogenesis of chronic pain; however, the exact mechanisms of chronification of LBP remain still unclear. The purpose of the present study was to analyse the neurostructural alterations in CLBP and to evaluate the role of comorbidities and their neurostructural underpinnings. METHODS: In the present study we investigated a well-characterized group of 14 patients with CLBP and 14 healthy controls applying structural MRI and psychometric measures. Using an improved algorithm for brain normalization (DARTEL) we performed a voxel-based morphometry (VBM) approach. Correlation analyses were performed to evaluate the role of anxiety and depression in neurostructural alterations observed in CLBP. RESULTS: The psychometric measures revealed significantly higher scores on depression and anxiety in the patient population. VBM analysis showed significant decreases in grey matter density in areas associated with pain processing and modulation, i.e. the dorsolateral prefrontal cortex, the thalamus and the middle cingulate cortex. With respect to anxiety and depression scores, we did not observe any correlations to the structural data. CONCLUSIONS: In the present study we found compelling evidence for alterations of grey matter architecture in CLBP in brain regions playing a major role in pain modulation and control. Our results fit the hypothesis of a "brain signature" in chronic pain conditions. The results of the psychometric assessment underline the importance of an interdisciplinary therapeutic approach including orthopedic, neurological and psychological evaluation and treatment.

Diagnosis and treatment of spondylodiscitis in HIV-positive patients.

With an incidence between 1:100,000 and 1:250,000, spondylodiscitis is rare, but is increasingly reported due to longer life expectancy, risk factors, and comorbidities, with HIV+ patients being at greater risk. We reviewed the literature on the diagnostic tools, and on the benefits and drawbacks of different treatments of spondylodiscitis in HIV- positive patients. We discuss basic strategies and indications for surgery. Recently, the trend was toward early mobilization of patients after surgical treatment. Modern surgical and antibiotic treatment can prevent a recurrence in these patients. The decision to opt for conservative or surgical treatment should be made depending on the extent of infection and the responsible pathogen, without regard to HIV. However, these patients should be treated in a specialized hospital by an experienced interdisciplinary team of consultants.

Predictors of surgical, general and follow-up complications in lumbar spinal stenosis relative to patient age as emerged from the Spine Tango Registry.

INTRODUCTION: Published opinions regarding the outcomes and complications in older patients have a broad spectrum and there is a disagreement whether surgery in older patients entails a higher risk. Therefore this study examines the risk of surgery for lumbar spinal stenosis relative to age in the pooled data set of the Spine Tango registry. MATERIALS AND METHODS: Between May 2005 and February 2010 the database query resulted in 1,764 patients. The patients were subdivided into three socio-economically relevant age groups: <65 years, 65-74 years, ≥75 years. Frequencies for occurred surgical, general and follow-up complications were assessed. Multivariate and univariate logistic regressions were performed to reveal predictors for respective complication types. RESULTS AND DISCUSSION: Our study found that age, ASA status and blood loss were significant co-varieties for the occurrence of general complications. The risk of general complications is increased in older versus younger patients. Fusion or rigid stabilization does not lead to more complications. Surgical complications as well as complication rates at follow-up showed no significant age-related variation. Physician-based outcome was good or excellent in over 80% of patients in all age groups.

Treatment of spondylodiscitis.

PURPOSE: Pyogenic infections of the spine are relatively rare with an incidence between 1:100,000 and 1:250,000 per year, but the incidence is increasing due to increases in average life-expectancy, risk factors, and medical comorbidities. The mean time in hospital varies from 30 to 57 days and the hospital mortality is reported to be 2-17%. This article presents the relevant literature and our experience of conservative and surgical treatment of pyogenic spondylodiscitis. METHOD: We have performed a review of the relevant literature and report the results of our own research in the diagnosis and treatment of pyogenic spondylodiscitis. We present a sequential algorithm for identification of the pathogen with blood cultures, CT-guided biopsies and intraoperative tissue samples. Basic treatment principles and indications for surgery and our surgical strategies are discussed. RESULTS: Recent efforts have been directed toward early mobilisation of patients using primary stable surgical techniques that lead to a further reduction of the mortality. Currently our hospital mortality in patients with spondylodiscitis is around 2%. With modern surgical and antibiotic treatment, a relapse of spondylodiscitis is unlikely to occur. In literature the relapse rate of 0-7% has been recorded. Overall the quality of life seems to be more favourable in patients following surgical treatment of spondylodiscitis. CONCLUSION: With close clinical and radiological monitoring of patients with spondylodiscitis, conservative and surgical therapies have become more successful. When indicated, surgical stabilisation of the infected segments is mandatory for control of the disease and immediate mobilisation of the patients.

Complications of vertebroplasty and kyphoplasty in the treatment of vertebral fractures: results of a questionnaire study.

Percutaneous vertebroplasty (VP) and balloon kyphoplasty (BKP) are minimally invasive procedures performed to stabilize vertebral fractures. With continuing expansion in clinical use, a broad spectrum of complications has been reported for both interventions. The goal of the current study was to compare the safety of these procedures using a questionnaire completed by practitioners. A questionnaire was developed with multiple choice and open questions. General data as well as information regarding complications which occurred during the year 2007 were requested. The incidence and odds ratios (OR) of complications for both procedures were analysed. One hundred and sixteen questionnaires detailing 3216 VP and 5139 BKP procedures were included for evaluation. The risk of cement extrusion from the vertebra (OR 2.64, p <0.01) and into the spinal canal (OR 435, p <0.01) was markedly increased for VP. The odds ratio for neurologic complications (OR 2.56, p = 0.1) and secondary fracture (OR = 0.99, p = 0.96) did not indicate significant predisposition for either procedure. Secondary fracture occurred in 5% of VP and 5.1% of BKP procedures. Overall, 80% of practitioners subjectively considered BKP the safer procedure. Overall, BKP appears safer than VP. Symptomatic complications are rare with both procedures. Additional prospective data is necessary to reach more definitive conclusions.

Lumbar Facet Joint Radiofrequency Denervation Therapy for Chronic Low Back Pain: Enhanced Outcome Compared With Chemical Neurolysis (Ethyl Alcohol 95% or Glycerol 20%).

BACKGROUND: It was hypothesized that radiofrequency denervation (RFD) of lumbar facet joints is associated with superior pain abolishment and less complications than chemical neurolysis (with ethyl alcohol or glycerol) in patients with chronic facet joint arthropathy. METHODS: For this prospective cohort study, adult patients with chronic lumbar facet joint arthropathy were prospectively enrolled between 2017 and 2019. The following groups were compared before the intervention and 6 weeks, 6 months, and 12 months after the intervention: RFD, chemical neurolysis with ethyl alcohol 95% (EA-95), or glycerol 20% (Gly-20). Outcome parameters included the Core Outcome Measures Index for the back (COMI-back), World Health Organization (WHO) pain ladder level, and visual analog scale (VAS). P values <0.05 were considered statistically significant. RESULTS: A total of 95 patients with a mean age of 63.7 years were included. Among them, 30 patients underwent RFD, 30 patients were treated with EA-95, and 35 individuals were treated with Gly-20. After 6 weeks, RFD patients had significantly lower VAS scores compared with the EA-95 group. After 6 months, both VAS and COMI were significantly lower in RFD patients than in the Gly-20 group. Twelve months after intervention, VAS scores were significantly lower in the RFD group compared with the Gly-20 group. CONCLUSIONS: This study reveals that RFD is associated with improved pain relief and quality of life compared with chemical neurolysis for facet joint-related chronic lower back pain and should be considered as the treatment of choice in patients with chronic low back pain due to facet joint arthropathy. CLINICAL RELEVANCE: The current study provides information that may improve clinical decision making in the treatment of chronic lumbar facet joint arthropathy and to appropriately counsel such patients about expected outcomes.

Comparison of standard fusion with a "topping off" system in lumbar spine surgery: a protocol for a randomized controlled trial.

BACKGROUND: Fusion of lumbar spine segments is a well-established therapy for many pathologies. The procedure changes the biomechanics of the spine. Initial clinical benefits may be outweighed by ensuing damage to the adjacent segments. Various surgical devices and techniques have been developed to prevent this deterioration. "Topping off" systems combine rigid fusion with a flexible pedicle screw system to prevent adjacent segment disease (ASD). To date, there is no convincing evidence that these devices provide any patient benefits. METHODS/DESIGN: The study is designed as a randomized, therapy-controlled trial in a clinical care setting at a university hospital. Patients presenting to the outpatient clinic with degenerative disc disease or spondylolisthesis will be assessed against study inclusion and exclusion criteria. After randomization, the control group will undergo conventional fusion. The intervention group will undergo fusion with a supplemental flexible pedicle screw system to protect the adjacent segment ("topping off").Follow-up examination will take place immediately after treatment during hospital stay, after 6 weeks, and then after 6, 12, 24 and 36 months. Subsequently, ongoing assessments will be performed annually.Outcome measurements will include quality of life and pain assessments using questionnaires (SF-36™, ODI, COMI). In addition, clinical and radiologic ASD, work-related disability, and duration of work disability will be assessed. Inpatient and 6-month mortality, surgery-related data (e.g., intraoperative complications, blood loss, length of incision, surgical duration), postoperative complications, adverse events, and serious adverse events will be documented and monitored throughout the study. Cost-effectiveness analysis will also be provided. DISCUSSION: New hybrid systems might improve the outcome of lumbar spine fusion. To date, there is no convincing published data on effectiveness or safety of these topping off systems. High quality data is required to evaluate the benefits and drawbacks of topping off devices. If only because these devices are quite expensive compared to conventional fusion implants, nonessential use should be avoided. In fact, these high costs necessitate efforts by health care providers to evaluate the effects of these implants. Randomized clinical trials are highly recommended to evaluate the benefits or harm to the patient. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01224379.

Multilevel spinal fusion in the aged: not a panacea.

The authors conducted a retrospective study on the outcome after multilevel spine fusion in elderly patients. Seventy-two out of 80 patients were available after a mean follow-up period of 29.4 months. There were 47 females and 25 males. Their mean age at operation was 68.7 years, which means that many complaints may have been due to an underlying osteoporosis, unresponsive to surgical treatment, and exposing to loosening of the implants. The outcome was indeed rather poor: only 50% of the patients were satisfied. VAS and ODI improved slightly, but not significantly. Implant loosening was the main complication: it occurred in 35 patients, but necessitated re-operation in only 8. Adjacent segment degeneration (ASD) occurred in 26 patients, and necessitated re-operation in 17. This study should be a warning against an interventionist attitude in older patients with so-called spondylosis, where osteoporosis should be excluded and, if present, should be treated as a first step.