Showing papers in "European Spine Journal in 2020"

Prevalence of lumbar spinal stenosis in general and clinical populations: a systematic review and meta-analysis

Abstract: To estimate the prevalence of degenerative lumbar spinal stenosis (LSS) in adults, identified by clinical symptoms and/or radiological criteria. Systematic review of the literature. Pooled prevalence estimates by care setting and clinical or radiological diagnostic criteria were calculated and plotted [PROSPERO ID: CRD42018109640]. In total, 41 papers reporting on 55 study samples were included. The overall risk of bias was considered high in two-thirds of the papers. The mean prevalence, based on a clinical diagnosis of LSS in the general population, was 11% (95% CI 4–18%), 25% (95% CI 19–32%) in patients from primary care, 29% (95% CI 22–36%) in patients from secondary care and 39% (95% CI 39–39%) in patients from mixed primary and secondary care. Evaluating the presence of LSS based on radiological diagnosis, the pooled prevalence was 11% (95% CI 5–18%) in the asymptomatic population, 38% (95% CI − 10 to 85%) in the general population, 15% (95% CI 13–18%) in patients from primary care, 32% (95% CI 22–41%) in patients from secondary care and 21% (95% CI 16–26%) in a mixed population from primary and secondary care. The mean prevalence estimates based on clinical diagnoses vary between 11 and 39%, and the estimates based on radiological diagnoses similarly vary between 11 and 38%. The results are based on studies with high risk of bias, and the pooled prevalence estimates should therefore be interpreted with caution. With an growing elderly population, there is a need for future low risk-of-bias research clarifying clinical and radiological diagnostic criteria of lumbar spinal stenosis. These slides can be retrieved under Electronic Supplementary Material.

Mechanical complications in adult spinal deformity and the effect of restoring the spinal shapes according to the Roussouly classification: a multicentric study.

Abstract: To evaluate the incidence of mechanical complications in patients with adult spine deformity (ASD) treated by restoring the normal shape according to the Roussouly classification. This is a retrospective multicentric study with a minimum follow-up of 2 years. Patients operated on with fusion for ASD (minimum performed fusion: L2 to sacrum) were included. Patients with a history of previous spinal fusion of more than three levels were excluded. Spinal and pelvic parameters were measured on the preoperative and the immediate postoperative follow-up. All mechanical complications were recorded. A total of 290 patients met the criteria of inclusion with a minimum follow-up of 2 years. Mechanical complications occurred in 30.4% of the cohort. The most common complication was PJK with an incidence of 18% while nonunion or instrumentation failure (rod breakage, implant failure) occurred in 12.4%. 66% of the patients were restored to the normal shape according to the Roussouly classification based on their PI and had a mechanical complication rate of 22.5%, whereas the remaining 34% of patients had a complication rate of 46.8% (p < 0.001). The relative risk for developing a mechanical complication if the algorithm was not met was 3 (CI 1.5–4.3; p < 0.001) In the recent literature, there are no clear guidelines for ASD correction. Restoring the sagittal spinal contour to the normal shapes of Roussouly according to the PI could serve as a guideline for ASD treatment. Ignoring this algorithm has a threefold risk of increased mechanical complications. We recommend this algorithm for treatment of ASD. IV cross-sectional observational study. These slides can be retrieved under Electronic Supplementary Material.

Augmented reality and artificial intelligence-based navigation during percutaneous vertebroplasty: a pilot randomised clinical trial

Abstract: To assess technical feasibility, accuracy, safety and patient radiation exposure of a novel navigational tool integrating augmented reality (AR) and artificial intelligence (AI), during percutaneous vertebroplasty of patients with vertebral compression fractures (VCFs). This prospective parallel randomised open trial compared the trans-pedicular access phase of percutaneous vertebroplasty across two groups of 10 patients, electronically randomised, with symptomatic single-level VCFs. Trocar insertion was performed using AR/AI-guidance with motion compensation in Group A, and standard fluoroscopy in Group B. The primary endpoint was technical feasibility in Group A. Secondary outcomes included the comparison of Groups A and B in terms of accuracy of trocar placement (distance between planned/actual trajectory on sagittal/coronal fluoroscopic images); complications; time for trocar deployment; and radiation dose/fluoroscopy time. Technical feasibility in Group A was 100%. Accuracy in Group A was 1.68 ± 0.25 mm (skin entry point), and 1.02 ± 0.26 mm (trocar tip) in the sagittal plane, and 1.88 ± 0.28 mm (skin entry point) and 0.86 ± 0.17 mm (trocar tip) in the coronal plane, without any significant difference compared to Group B (p > 0.05). No complications were observed in the entire population. Time for trocar deployment was significantly longer in Group A (642 ± 210 s) than in Group B (336 ± 60 s; p = 0.001). Dose–area product and fluoroscopy time were significantly lower in Group A (182.6 ± 106.7 mGy cm2 and 5.2 ± 2.6 s) than in Group B (367.8 ± 184.7 mGy cm2 and 10.4 ± 4.1 s; p = 0.025 and 0.005), respectively. AR/AI-guided percutaneous vertebroplasty appears feasible, accurate and safe, and facilitates lower patient radiation exposure compared to standard fluoroscopic guidance. These slides can be retrieved under Electronic Supplementary Material.

3D-printed spine surgery implants: a systematic review of the efficacy and clinical safety profile of patient-specific and off-the-shelf devices.

Abstract: Unfortunately, 3rd author's first name was incorrectly published in the original publication. The complete correct name is given below.

Prone single-position extreme lateral interbody fusion (Pro-XLIF): preliminary results.

Abstract: Single-position options for combined anterior and posterior fusion in the lumbar spine have been suggested to reduce the surgical time and improve the efficiency of operating room. Previous reports have focused on lateral decubitus single-position surgery. The goal of this study is to describe and evaluate the feasibility and safety of prone single-position extreme lateral interbody fusion (XLIF) with posterior fixation. Design Pilot prospective non-randomized controlled study. Seven patients who underwent prone single-position XLIF and posterior fixation were evaluated (Pro-XLIF). A control group (Std-XLIF) was composed of ten patients who underwent XLIF in lateral decubitus and posterior fixation in prone position. All patients underwent interbody XLIF fusion at one level and posterior procedures at one or more levels. Duration of surgery, blood loss, complications, X-ray use and clinical outcomes were recorded. No major complications were observed in either group. Oswestry Disability Index, back pain and leg pain were improved in the Pro-XLIF group from 48.5, 7.7 and 8.5 to 14.5, 1.71 and 2.71, respectively, and in the Std-XLIF group from 50.8, 5.7 and 7.2 to 22.5, 3.7 and 2.5. The Pro-XLIF group had a longer time of preparation before incision (39 vs 26 min, ns), equal duration of the anterior procedure (65 vs 59 min, ns), shorter duration of surgery (133 vs 182 min, ns) and longer X-ray exposure time (102 vs 92 s, ns). The surgical technique is described. Prone single-position XLIF is feasible and safe. In this preliminary report, the results are comparable to the standard technique. These slides can be retrieved under Electronic Supplementary Material.

Worldwide research productivity in the field of full-endoscopic spine surgery: a bibliometric study

Abstract: To investigate the quantity and quality of articles in the field of full-endoscopic spine surgery (FESS) from different countries and assess characteristics of worldwide research productivity. Articles published from 1997 to July 23, 2018, were screened using the Web of Science database. All studies were assessed for the following parameters: the number of total publications, h-index, contribution of countries, authors, journals, and institutions. A total of 408 articles were identified between 1997 and 2018. Between 1997 and 2017, the number of published articles tended to increase by 41 times. The largest number of articles was from China (30.15%), followed by South Korea (28.68%), the USA (13.97%), Germany (9.31%), and Japan (4.90%). The highest h-index was found for articles from South Korea (23), followed by the USA (18), Germany (16), China (11), and Japan (7). The highest number of articles was published in World Neurosurgery (12.50%), followed by Pain Physician (10.29%), Spine (6.62%), European Spine Journal (4.66%), and Journal of Neurosurgery: Spine (4.17%). Wooridul Spine Hospital published the largest number of articles (10.29%), followed by Tongji University (5.88%), University of Witten/Herdecke (5.39%), Brown University (5.15%), and Third Military Medical University (3.43%). The number of articles published in the field of FESS has increased rapidly in the past 20 years. In terms of quantity, China is the most contributive country based on the number of publications. High-quality papers as measured by h-index and the large quantity is from South Korea (second only to China). These slides can be retrieved under Electronic Supplementary Material.

Restoring the ideal Roussouly sagittal profile in adult scoliosis surgery decreases the risk of mechanical complications.

Abstract: There are still no data proving whether restoring the ideal sagittal profile (according to Roussouly classification) in adult scoliosis (AS) patients leads to any additional benefit, especially regarding mechanical complications. Retrospective analysis of operated AS patients recorded in a prospective multicenter database. Demographic and radiographic (preoperative and 6-week postoperative) data were analyzed. Patients with and without mechanical complications were compared looking especially at the surgical restoration of the ideal (based on Pelvic Incidence) sagittal profile. Univariate and multivariate analysis was performed to identify causes of mechanical complications at 2-year minimum follow-up. Ninty-six AS patients were analyzed. Thirty-nine patients suffered a mechanical complication (18 PJK, 11 pseudoarthrosis, 10 screw pull-out), and 57 patients had no mechanical complications. Postoperatively, 72% of patients not matching the ideal Roussouly-type suffered mechanical complications compared to 15% of matched patients (P < 0.001). Univariate analysis showed that older patients 64.9 ± 13 versus 40.7 ± 15.6 years (P < 0.001), higher postoperative Global Tilt (27° vs. 14.7°) and Pelvic Tilt (25° vs. 16°) (P < 0.001), upper instrumented vertebra at the thoracolumbar junction (62% vs. 21%) (P < 0.001), fixation to the Iliac (76% vs. 6%) (P < 0.001), and postoperative Roussouly-type mismatch (72% vs. 15%) (P < 0.001) significantly increased the rate of mechanical complications. Multivariate logistic regression analysis selected: postoperative Roussouly-type mismatch (OR = 41.9; 95%CI = 5.5–315.7; P < 0.001), iliac instrumentation (OR = 19.4; 95%CI = 2.6–142.5; P = 0.004), and age (OR = 1.1; 95%CI = 1.02–1.16; P = 0.004), as the most important variables. Adult scoliosis surgery should restore the ideal Roussouly sagittal profile to decrease the rate of mechanical complications, especially in patients older than 65, instrumented to the pelvis. These slides can be retrieved under Electronic Supplementary Material.

Long-term outcomes following intraosseous basivertebral nerve ablation for the treatment of chronic low back pain: 5-year treatment arm results from a prospective randomized double-blind sham-controlled multi-center study.

Abstract: Damaged or degenerated vertebral endplates are a significant cause of vertebrogenic chronic low back pain (CLBP). Modic changes are one objective MRI biomarker for these patients. Prior data from the treatment arm of a sham-controlled, RCT showed maintenance of clinical improvements at 2 years following ablation of the basivertebral nerve (BVN). This study reports 5-year clinical outcomes. In total, 117 US patients were treated successfully with BVN ablation. Patient-reported outcomes of ODI, VAS, postablation treatments, and patient satisfaction were collected at a minimum of 5-years following BVN ablation. Primary outcome was mean change in ODI. Comparisons between the postablation and baseline values were made using an analysis of covariance with alpha 0.05. Of the 117 US treated patients 100 (85%) were available for review with a mean follow-up of 6.4 years (5.4–7.8 years). Mean ODI score improved from 42.81 to 16.86 at 5-year follow-up, a reduction of 25.95 points (p 50% reduction in pain, 47% reported a > 75% reduction in pain, and 34% of patients reported complete pain resolution. Composite responder rate using thresholds of ≥ 15-point ODI and ≥ 2-point VAS for function and pain at 5 years was 75%. CLBP patients treated with BVN ablation exhibit sustained clinical improvements in function and pain with high responder rates at a mean of 6.4 years following treatment. BVN ablation is a durable, minimally invasive treatment for vertebrogenic CLBP.

Simultaneous single-position lateral interbody fusion and percutaneous pedicle screw fixation using O-arm-based navigation reduces the occupancy time of the operating room.

Abstract: Lateral interbody fusion and posterior percutaneous pedicle screw (LIF-PPS) fixation has been performed in two-stage positioning. The aim of this study was to investigate the surgical outcomes of simultaneous single-position LIF-PPS fixation using O-arm-based navigation. Overall, 102 consecutive subjects underwent indirect decompression surgery for spondylolisthesis with LIF-PPS fixation. Fifty-one subjects underwent surgery with repositioning, and 51 in the right lateral decubitus position. We compared these two groups in terms of the surgery time, occupancy time in the operating room, intraoperative blood loss, Japanese Orthopaedic Association (JOA) score, local lordosis acquisition in postoperative radiographs, and accuracy of screw insertion using postoperative CT scans. In the single-position group, surgery time, occupancy time of the operating room, and estimated blood loss were 93.3 ± 19.3 min (vs. the repositioning group: 121.0 ± 37.1 min; p < 0.001), 176.3 ± 36.4 min (vs. 272.4 ± 42.7 min; p < 0.001), and 93.4 ± 78.8 ml (vs. 40.9 ± 28.7 ml; p < 0.001), respectively. The JOA scores (pre-/postoperative) were 15.1 ± 3.0/24.4 ± 2.8 (p < 0.001) for the single-position group and 15.1 ± 4.0/24.8 ± 3.0 (p < 0.001) for the repositioning group. The rate of misplacement was 1.8% versus 4.0%, respectively (p = 0.267), and the lordosis acquisition was 4.2° ± 4.1° versus 4.4° ± 3.2°, respectively (p = 0.516). Single-position surgery exhibited comparable clinical outcomes and local lordosis acquisition with conventional repositioning LIF-PPS fixation. This single-position minimally invasive technique reduces the occupancy time of the operating room and workforce requirements. These slides can be retrieved under Electronic Supplementary Material.

The prevalence and clinical characteristics of thoracic spinal stenosis: a systematic review

Abstract: Thoracic spinal stenosis (TSS) is a rare disease secondary to multiple pathological changes that differ in prevalence and clinical characteristics. The epidemiological characteristics of these pathologies are largely unknown due to the limited case samples and regional differences. Therefore, a systematic review was conducted to elucidate the prevalence and clinical characteristics of TSS. Case series and case reports on the ossification of the posterior longitudinal ligaments (OPLL), ossification of the ligamentum flavum (OLF) and thoracic disk herniation (TDH) were screened from PubMed, Embase and Web of Science databases and systematically reviewed. Epidemiological, demographic and segmental distribution data were extracted and analyzed. A total of 129 studies including 1935 subjects were selected, of which 361 (18.7%) were diagnosed with OPLL, 804 (41.5%) with OLF, 143 (7.4%) with OPLL + OLF and 627 (32.4%) with TDH. Most reports were from China, Japan and USA. Thoracic OPLL occurred mostly at the middle-thoracic spine (43.4%), while OLF predominately occurred at the lower-thoracic spine (63.1%). TDH was mainly localized in the middle (46.0%) and lower-thoracic (50.3%) spine. Thirty-two studies involving 524 patients described tandem spinal stenosis, of which 52.1% had accompanying cervical diseases and 35.9% lumbar diseases. There are significant differences in the age, sex and segment distribution characteristics of different pathologies leading to TSS. Tandem spinal stenosis is not uncommon and should be considered when diagnosing TSS. Our findings provide new insights into the prevalence and clinical characteristics of TSS and can help reduce misdiagnosis.

Hounsfield units value is a better predictor of pedicle screw loosening than the T-score of DXA in patients with lumbar degenerative diseases.

Abstract: To compare the performance of using Hounsfield units (HU) value derived from computed tomography and T-score of dual-energy X-ray absorptiometry (DXA) to predict pedicle screw loosening. We reviewed 253 patients aged ≥ 50 years undergoing pedicle screw fixation for lumbar degenerative diseases (LDD). The evaluation of screw loosening: radiolucent zones of ≥ 1 mm thick in X-ray. The criterion for osteoporosis: the lowest T-score ≤ − 2.5. The average HU value of L1–L4 was used to represent lumbar bone mineral density (BMD). The area under receiver operating characteristics curve (AUC) was used to evaluate the performance of predicting screw loosening. One patient underwent reoperation for screw loosening at 9 months follow-up. At 12 months follow-up, the loosening rate was 30.6% (77/252) in the remaining 252 patients. Osteoporotic patients had higher loosening rate than non-osteoporotic patients (39.3% vs. 25.8%, P = 0.026). The T-score showed no significant difference between loosening group and non-loosening group (− 2.1 ± 1.5 vs. − 1.7 ± 1.6, P = 0.074), and so is the lowest lumbar BMD of DXA (0.83 ± 0.16 g/cm2 vs. 0.88 ± 0.19 g/cm2, P = 0.054). The HU value was lower in the loosening group (106.8 ± 34.4 vs. 129.8 ± 45.7, P < 0.001). The HU value (OR, 0.980; 95%CI 0.968–0.993; P = 0.002) was the independent influencing factor of screw loosening. The AUC of predicting screw loosening was 0.666 (P < 0.001) for HU value and 0.574 (P = 0.062) for T-score. HU value is a better predictor of pedicle screw loosening than T-score of DXA in patients aged ≥ 50 years with LDD. We should not only focus on the DXA measurements when making surgical plans concerning lumbar fixation. These slides can be retrieved under Electronic Supplementary Material.

Low back pain: critical assessment of various scales

Abstract: To study the various pain assessment tools based on their psychometric properties and ease of use. Published articles on psychometric properties of pain tools were accessed and data collected for low back pain (LBP)-specific tools, generic tools, neuropathic LBP tools, tools for cognitively impaired patients, and tools for acute LBP. Among the LBP-specific tools, Roland Morris Disability Questionnaire (RMDQ) and Oswestry Disability Index (ODI) have good construct validity and reliability, and responsiveness over short intervals. Quebec Back Pain Disability Scale (QBPDS) gauges only disability and sleep. Among the generic tools, McGill Pain Questionnaire (MPQ), West Haven-Yale Multidimensional Pain Inventory (MPI), and Brief Pain Inventory (BPI) show good responsiveness, but BPI is the only tool validated for LBP. Neuropathic Pain Scale (NPS) and Short Form-MPQ-2 (SF-MPQ-2) are both reliable tools for neuropathic LBP. For cognitively impaired patients, Pain Assessment in Advanced Dementia (PAINAD), Abbey Pain Scale (APS), and Doloplus-2 are all reliable tools, but PAINAD has good construct validity. For acute pain, Clinically Aligned Pain Assessment (CAPA) is reliable and responsive, but presently, unidimensional tools and SF-MPQ-2 are the tools most preferred. Based on psychometric properties and ease of use, the best tools for LBP seem to be RMDQ/ODI (among LBP-specific tools), BPI (among generic tools), SF-MPQ-2/NPS (for neuropathic LBP), PAINAD (for cognitively impaired patients), and unidimensional tools and SF-MPQ-2 (for acute pain). Overall, BPI seems to be a tool that can be relied upon the most. These slides can be retrieved under Electronic Supplementary Material.

Complication rates of different discectomy techniques for symptomatic lumbar disc herniation: a systematic review and meta-analysis

Abstract: This meta-analysis aims to compare the complication rates of discectomy/microdiscectomy (OD/MD), microendoscopic discectomy (MED), percutaneous endoscopic lumbar discectomy (PELD), percutaneous laser disc decompression (PLDD), and tubular discectomy for symptomatic lumbar disc herniation (LDH) using general classification and modified Clavien–Dindo classification (MCDC) schemes. We searched three online databases for randomized controlled trials (RCTs) and cohort studies. Overall complication rates and complication rates per the above-mentioned classification schemes were considered as primary outcomes. Risk ratio (RR) and their 95% confidence intervals (CI) were evaluated. Seventeen RCTs and 20 cohort studies met the eligibility criteria. RCTs reporting OD/MD, MED, PELD, PLDD, and tubular discectomies had overall complication rates of 16.8% and 16.1%, 21.2%, 5.8%, 8.4%, and 25.8%, respectively. Compared with the OD/MD, there was moderate-quality evidence suggesting that PELD had a lower risk of overall complications (RR = 0.52, 95% CI 0.29–0.91) and high-quality evidence suggesting a lower risk of Type I complications per MCDC (RR = 0.37, 95% CI 0.16–0.81). Compared with the OD/MD data from cohort studies, there was low-quality evidence suggesting a higher risk of Type III complications per MCDC (RR = 10.83, 95% CI 1.29–91.18) for MED, higher risk of reherniations (RR = 1.67,95% CI 1.05–2.64) and reoperations (RR = 1.75, 95% CI 1.20–2.55) for PELD, lower risk of overall complication rates (RR = 0.42, 95% CI 0.25–0.70), post-operative complication rates (RR = 0.42, 95% CI 0.25–0.70), Type III complications per MCDC (RR = 0.39, 95% CI 0.22–0.69), reherniations (RR = 0.56, 95% CI 0.33–0.97) and reoperations (RR = 0.39, 95% CI 0.22–0.69) for PLDD. Compared with the OD/MD, results of this meta-analysis suggest that PELD has a lower risk of overall complications and a lower risk of complications necessitating conservative treatment. These slides can be retrieved under Electronic Supplementary Material.

Opioid-sparing multimodal analgesia with bilateral bi-level erector spinae plane blocks in scoliosis surgery: a case report of two patients

Abstract: Postoperative pain following scoliosis correction surgery is severe and usually requires prolonged intravenous opioid therapy. Regional anesthesia options are limited and include intrathecal opioid and epidural analgesia; however, they remain little used because of side effects and inconsistent efficacy. We describe a novel multimodal anesthetic regimen incorporating bilateral bi-level erector spinae plane (ESP) blocks together with a combination of several evidence-based intraoperative opioid-sparing analgesic strategies. Two healthy young adult patients with idiopathic scoliosis underwent posterior spinal fusion involving 12 vertebral levels (T2–L1 and T3–L2). Bilateral single-injection ESP blocks were performed at two levels (T4 and T10) prior to incision. Intraoperatively, patients received intravenous dexamethasone and infusions of dexmedetomidine and ketamine for multimodal analgesia. Remifentanil was omitted from the total intravenous anesthetic regimen to avoid opioid-induced hyperalgesia. Both patients had minimal pain on emergence. They transitioned successfully to oral analgesia on the first postoperative day, with modest opioid requirements, no side effects, and low pain scores throughout their hospital stay. Bilateral bi-level ESP blocks are a simple method of providing pre-emptive regional analgesia in extensive multi-level spine surgery. Integration of ESP blocks into a multimodal regimen that employs other opioid-sparing strategies may have additive, and potentially synergistic, benefits in improving postoperative analgesia and reducing opioid requirements.

ISSLS Prize in Clinical Science 2020. Examining causal effects of body mass index on back pain: a Mendelian randomization study

Abstract: Measures of body fat accumulation are associated with back pain, but a causal association is unclear. We hypothesized that BMI would have causal effects on back pain. We conducted a two-sample Mendelian randomization (MR) study to assess the causal effect of body mass index (BMI) on the outcomes of (1) back pain and (2) chronic back pain (duration > 3 months). We identified genetic instrumental variables for BMI (n = 60 variants) from a meta-analysis of genome-wide association studies (GWAS) conducted by the Genetic Investigation of ANthropometric Traits consortium in individuals of European ancestry (n = 322,154). We conducted GWAS of back pain and chronic back pain (n = 453,860) in a non-overlapping sample of individuals of European ancestry. We used inverse-variance weighted (IVW) meta-analysis as the primary method to estimate causal effects. The IVW analysis showed evidence supporting a causal association of BMI on back pain, with a 1-standard deviation (4.65 kg/m2) increase in BMI conferring 1.15 times the odds of back pain (95% confidence interval [CI]: 1.06–1.25, p = 0.001]; effects were directionally consistent in secondary analysis and sensitivity analyses. The IVW analysis supported a causal association of BMI on chronic back pain (OR 1.20 per 1 SD deviation increase in BMI [95% CI 1.09–1.32; p = 0.0002]), and effects were directionally consistent in secondary analysis and sensitivity analyses. In this first MR study of BMI and back pain, we found a significant causal effect of BMI on both back pain and chronic back pain. These slides can be retrieved under Electronic Supplementary Material.

The association of cervical sagittal alignment with adjacent segment degeneration

Abstract: Cervical spine surgery may affect sagittal alignment parameters and induce accelerated degeneration of the cervical spine. Cervical sagittal alignment parameters of surgical patients will be correlated with radiological adjacent segment degeneration (ASD) and with clinical outcome parameters. Patients were analysed from two randomized, double-blinded trials comparing anterior cervical discectomy with arthroplasty (ACDA), with intervertebral cage (ACDF) and without intervertebral cage (ACD). C2–C7 lordosis, T1 slope, C2–C7 sagittal vertical axis (SVA) and the occipito-cervical angle (OCI) were determined as cervical sagittal alignment parameters. Radiological ASD was scored by the combination of decrease in disc height and anterior osteophyte formation. Neck disability index (NDI), SF-36 PCS and MCS were evaluated as clinical outcomes. The cervical sagittal alignment parameters were comparable between the three treatment groups, both at baseline and at 2-year follow-up. Irrespective of surgical method, C2–C7 lordosis was found to increase from 11° to 13°, but the other parameters remained stable during follow-up. Only the OCI was demonstrated to be associated with the presence and positive progression of radiological ASD, both at baseline and at 2-year follow-up. NDI, SF-36 PCS and MCS were demonstrated not to be correlated with cervical sagittal alignment. Likewise, a correlation with the value or change of the OCI was absent. OCI, an important factor to maintain horizontal gaze, was demonstrated to be associated with radiological ASD, suggesting that the occipito-cervical angle influences accelerated cervical degeneration. Since OCI did not change after surgery, degeneration of the cervical spine may be predicted by the value of OCI. Dutch Trial Register Number NTR1289. Trial Register Number ISRCTN41681847. These slides can be retrieved under Electronic Supplementary Material.

Quality of complementary and alternative medicine recommendations in low back pain guidelines: a systematic review.

Abstract: Individuals with low back pain (LBP) often turn to complementary and alternative medicine (CAM) to seek relief. The purpose of this study was to determine mention of CAM in LBP clinical practice guidelines and assess the quality of CAM recommendations using the Appraisal of Guidelines, Research and Evaluation II (AGREE II) instrument. A systematic review was conducted to identify LBP guidelines. MEDLINE, EMBASE and CINAHL were searched from 2008 to 2018. The Guidelines International Network and the National Center for Complementary and Integrative Health websites were also searched. Eligible guidelines providing CAM recommendations were assessed with the AGREE II instrument. From 181 unique search results, 22 guidelines on the treatment and/or management of LBP were found, and 17 made recommendations on CAM therapy. With regard to scaled domain percentages, this overall guideline scored higher than the CAM section for 4 of 6 domains (overall, CAM): (1) scope and purpose (88.6%, 87.1%), (2) clarity of presentation (83.0%, 73.2%), (3) stakeholder involvement (57.0%, 41.7%), (4) rigor of development (47.2%, 44.7%), (5) editorial independence (34.8%, 34.8%) and (6) applicability (31.8%, 21.8%). The majority of LBP guidelines made CAM recommendations. The quality of CAM recommendations is significantly lower than overall recommendations across all domains with the exception of scope and purpose and editorial independence. This difference highlights the need for CAM recommendation quality improvement. Future research should identify CAM therapies which are supported by sufficient evidence to serve as the basis for guideline development. These slides can be retrieved under Electronic Supplementary Material.

Human intervertebral discs harbour a unique microbiome and dysbiosis determines health and disease

Abstract: To document the role of sub-clinical infections in disc disorders and investigate the existence of microbiome in intervertebral discs (IVD). Genomic DNA from 24 lumbar IVDs [8—MRI normal discs (ND) from brain dead yet alive organ donors, 8—disc herniation (DH), 8—disc degeneration (DD)] was subjected to 16SrRNA sequencing for profiling the diversity of human disc microbiome in health and disease. The disc microbiome was further compared to established human gut and skin microbiomes. All healthy MRI normal discs from brain dead yet alive organ donors also had a rich bacterial presence. A total of 424 different species (355-ND, 346-DD, and 322-DH) were detected, with 42.75% OTUs being classified at kingdom level, 44% at the phylum level, 22.62% at genus level, and 5.5% at species level. Varying biodiversity and abundance between healthy and diseased discs were documented with protective bacteria being abundant in normal discs, and putative pathogens abundant in DD and DH. Propionibacterium acnes had a similar but lower abundance to other pathogens in all three groups ND (3.07%), DD (3.88%), DH (1.56%). Fifty-eight bacteria were common between gut and IVD microbiomes, 29 between skin and IVD microbiomes, and six common to gut/skin/IVD. Our study challenges the hitherto concept of sterility in healthy IVD and documented a microbiome even in MRI normal healthy discs. The varying abundance of bacteria between ND, DD, and DH documents ‘dysbiosis’ as a possible etiology of DD. Many known pathogens were identified in greater abundance than Propionibacterium acnes, and there was evidence for the presence of the gut/skin/spine microbiome axis.

Unique biomechanical signatures of Bryan, Prodisc C, and Prestige LP cervical disc replacements: a finite element modelling study.

Abstract: The purpose of the study is to examine the biomechanical alterations in the index and adjacent levels of the human cervical spine after cervical arthroplasty with Bryan, Prodisc C, or Prestige LP. A previously validated C2–T1 osteoligamentous finite element model was used to perform virtual C5–6 arthroplasty using three different FDA-approved artificial cervical discs. Motion-controlled moment loading protocol was used. Moment was varied until Bryan, Prodisc C, and Prestige LP models displayed the same total range of motion across C3–C7 as the intact spine model at 2 Nm of pure moment loading. Range of motion (ROM) and facet force (FF) were recorded at the index level. ROM, FF, and intradiscal pressure (IDP) were recorded at the adjacent levels. Prodisc C and Prestige LP led to supraphysiologic ROM and FF at the index level while decreasing ROM and FF at the adjacent levels. In contrast, Bryan reduced ROM and FF at the index level. Bryan increased ROM and FF at the adjacent levels in flexion, but decreased ROM and FF in the adjacent levels in extension. Prodisc C decreased IDP at the adjacent levels. Bryan reduced IDP in extension only. Prestige LP increased adjacent-level IDP. The distinct designs and material compositions of the three artificial discs result in varying biomechanical alterations at the index and adjacent levels in the cervical spine after implantation. The findings confirm the design and material influence on the spine biomechanics, as well as the advantages and contraindications of cervical arthroplasty in general. These slides can be retrieved under Electronic Supplementary Material.

Endplate volumetric bone mineral density measured by quantitative computed tomography as a novel predictive measure of severe cage subsidence after standalone lateral lumbar fusion

Abstract: Quantitative computed tomography (QCT) is an alternate imaging method to dual X-ray absorptiometry to measure bone mineral density (BMD). One advantage of QCT is that it allows site-specific volumetric BMD (vBMD) measurements in a small region. In this study, we utilized site-specific, endplate vBMD (EP-vBMD) as a potential predictive marker of severe cage subsidence in standalone lateral lumbar interbody fusion (SA-LLIF) patients and conducted a retrospective comparative study between EP-vBMD and trabecular vBMDs (Tb-vBMD) in the vertebrae. Patients undergoing SA-LLIF from 2007 to 2016 were retrospectively reviewed. EP-vBMD was defined as the average of the upper and lower endplate volumetric BMDs measured in cortical and trabecular bone included in a 5-mm area of interest beneath the cage contact surfaces. We compared Tb-vBMDs and EP-vBMDs between disk levels that had severe cage subsidence and levels with no severe subsidence. Both EP-vBMD and Tb-vBMD could be measured in 210 levels of 96 patients. Severe cage subsidence was observed in 58 levels in 38 patients. Median (IQR) Tb-vBMD was 120.5 mg/cm3 (100.8–153.7) in the non-severe subsidence group and 117.9 mg/cm3 (90.6–149.5) in the severe subsidence group (p = 0.393), whereas EP-vBMD was significantly lower in the severe subsidence group than the non-severe subsidence group (non-severe subsidence 257.4 mg/cm3 (216.3–299.4), severe subsidence 233.5 mg/cm3 (193.4–273.3), p = 0.026). We introduced a novel site-specific vBMD measurement for cage subsidence risk assessment. Our results showed that EP-vBMD was a reproducible measurement and appeared more predictive for severe cage subsidence after SA-LLIF than Tb-vBMD. These slides can be retrieved under Electronic Supplementary Material.

Denosumab in the treatment of giant cell tumor of the spine. Preliminary report, review of the literature and protocol proposal.

Abstract: The interest on the role of Denosumab in the treatment strategy of giant cell tumor of the spine is growing. En bloc resection is considered the Enneking appropriate treatment, but morbidity and functional loss are sometimes unacceptable. Denosumab could play a role as a stand-alone treatment, but also as preoperative treatment or as postoperative after intralesional surgery. A cohort of 10 out of 12 cases of spinal GCT consecutively treated with Denosumab are analyzed and discussed compared to the cases reported in the literature. A staging of the radiological effect of the treatment is proposed. The stand-alone and postoperative treatments are still running (12 to 88 months). One therapy was stopped after 15 months, once a satisfactory local effect was achieved, but the treatment had to be restarted 2 months later due to the recurrence of the erosive images. The new treatment was successful. At 1-year follow-up after the gross total excision followed by postoperative Denosumab treatment, no evidence of local recurrence was found. The preoperative treatment duration ranged from 3 to 24 months. No local recurrence followed the en bloc resections. Denosumab alone is effective in relieving pain, increasing the ossification and sometimes reducing the tumor volume. It can be considered an excellent solution in spine GCTs whose surgical treatment cannot be Enneking appropriate or is associated with unacceptable morbidity or loss of functions. It is still impossible to state when to safely stop the treatment. Denosumab also plays a role as preoperative protocol. These slides can be retrieved under Electronic Supplementary Material.

Prosthesis design influences segmental contribution to total cervical motion after cervical disc arthroplasty.

Abstract: We investigated a new metric for assessing the quality of motion of the cervical segments over the arc of extension-to-flexion motion after cervical disc arthroplasty (CDA). We quantified: (1) the amount of motion contributed by individual spinal segments to the total cervical spine motion, termed segmental motion fraction, and its variation throughout the arc of extension-to-flexion motion and (2) how cervical disc arthroplasty using two distinct prosthesis designs may influence the segmental motion contributions. We tested 16 human C3–T1 spine specimens under physiologic loads; first intact, after CDA at C5–C6, and then at C5–C6 and C6–C7. The M6-C (Orthofix, USA) and Mobi-C (Zimmer, USA) disc prostheses were used in eight specimens each. The designs of the cervical disc prostheses tested significantly influenced the variation in segmental motion fraction as the spine underwent motion between the endpoints of extension and flexion. While the mean segmental motion contribution to the total cervical motion was not influenced by prosthesis design, the way the motion took place between the extension and flexion endpoints was significantly influenced. The M6-C artificial disc restored physiologic motion quality such that implanted segments continued to function in harmony with other segments of the cervical spine as measured before arthroplasty. Conversely, the Mobi-C prosthesis, while maintaining average motion contributions similar to the pre-implantation values, demonstrated large deviations in motion contribution over the extension-to-flexion arc motion in ten of 16 implanted segments. Such non-physiologic implant kinematics could cause excessive prosthesis wear and motion and stress shielding at adjacent segments. These slides can be retrieved under Electronic Supplementary Material.

Meta-analysis of the validity and reliability of rasterstereographic measurements of spinal posture

Abstract: We provide a meta-analysis for clinicians and researchers regarding reliability and validity of rasterstereographic measurement of the spinal posture. A comprehensive PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) literature search identified 19 eligible studies evaluating reliability and validity of static rasterstereographic measurements in healthy subjects and patients with different spinal pathologies. Our meta-analysis suggests that rasterstereography is a reliable and valid instrument to assess spinal posture parameters, especially thoracic kyphosis, lumbar lordosis, and scoliosis, reliability overall effect sizes rs > .91, ps 70, ps < .001, when compared to traditional radiological imaging techniques. Validity is higher in scoliosis patients compared with healthy controls. Limitations are a lack of reported statistics of the included studies and small sample sizes. The first meta-analysis on reliability and validity of rasterstereography shows satisfactory results. Rasterstereography thus presents a reliable and valid alternative to classic radiological imaging technique to assess and evaluate spinal posture in patients with spinal pathologies. Further studies are needed, focusing on the measurement properties of both static and dynamic rasterstereographic measurements.

A deep learning tool for fully automated measurements of sagittal spinopelvic balance from X-ray images: performance evaluation

Abstract: The purpose of this study is to evaluate the performance of a novel deep learning (DL) tool for fully automated measurements of the sagittal spinopelvic balance from X-ray images of the spine in comparison with manual measurements. Ninety-seven conventional upright sagittal X-ray images from 55 subjects were retrospectively included in this study. Measurements of the parameters of the sagittal spinopelvic balance, i.e., the sacral slope (SS), pelvic tilt (PT), spinal tilt (ST), pelvic incidence (PI) and spinosacral angle (SSA), were obtained manually by identifying specific anatomical landmarks using the SurgiMap Spine software and by the fully automated DL tool. Statistical analysis was performed in terms of the mean absolute difference (MAD), standard deviation (SD) and Pearson correlation, while the paired t test was used to search for statistically significant differences between manual and automated measurements. The differences between reference manual measurements and those obtained automatically by the DL tool were, respectively, for SS, PT, ST, PI and SSA, equal to 5.0° (3.4°), 2.7° (2.5°), 1.2° (1.2°), 5.5° (4.2°) and 5.0° (3.5°) in terms of MAD (SD), with a statistically significant corresponding Pearson correlation of 0.73, 0.90, 0.95, 0.81 and 0.71. No statistically significant differences were observed between the two types of measurement (p value always above 0.05). The differences between measurements are in the range of the observer variability of manual measurements, indicating that the DL tool can provide clinically equivalent measurements in terms of accuracy but superior measurements in terms of cost-effectiveness, reliability and reproducibility.

Risk factors for postoperative residual back pain after percutaneous kyphoplasty for osteoporotic vertebral compression fractures

Abstract: To determine the incidence of and risk factors for residual back pain in osteoporotic vertebral compression fracture (OVCF) patients after percutaneous kyphoplasty (PKP) treatment, we performed a retrospective analysis of prospective data. Patients who underwent bilateral PKP and met this study’s inclusion criteria were retrospectively reviewed. Back pain intensity was assessed using a visual analogue scale (VAS) after surgery. Residual back pain was defined as the presence of postoperative moderate-severe pain (average VAS score ≥ 4), and the variables included patient characteristics, baseline symptoms, radiological parameters and surgical factors. Univariate and multivariate logistic regression analyses were performed to identify risk factors. A total of 809 patients were included, and residual back pain was identified in 63 (7.8%) patients. Of these patients, 52 patients had complete data for further analysis. Multivariate logistic regression analysis showed that risk factors for back pain included the presence of an intravertebral vacuum cleft (OR 2.93, P = 0.032), posterior fascia oedema (OR 4.11, P = 0.014), facet joint violations (OR 12.19, P < 0.001) and a separated cement distribution (OR 2.23, P = 0.043). The incidence of postoperative residual back pain was 7.8% among 809 OVCF patients following PKP. The presence of an intravertebral vacuum cleft, posterior fascia oedema, facet joint violations and a separated cement distribution were identified as independent risk factors for residual back pain.

The contradictory effect of macrophage-related cytokine expression in lumbar disc herniations: a systematic review.

Abstract: Sciatic symptoms due to lumbar disc herniation are likely to be caused not solely by mechanical compression of the nerve root, but also by pain-inducing elements from inflammatory processes. Key components in the inflammatory reaction are M1 and M2 macrophages, with the M1 type being associated with pro-inflammatory processes and M2 with anti-inflammatory-processes. The present systematic review summarizes all studies on associations between M1 and M2 macrophages and their related inflammation factors and pain symptoms in lumbar disc herniations. Literature search was performed using an optimally sensitive search string. Studies were selected for inclusion by means of predefined inclusion and exclusion criteria and subsequently graded for risk of bias. A total of 14 studies were included. Overall risk of bias was moderate (8/14), and three studies had high risk of bias and three has low risk of bias. Regarding M1-related cytokines, high levels of TNF-α, TNFR1, IL-6, IL-8, and IFN-γ were all associated high VAS scores. In contrast, high levels of TNFR2 were associated with lower VAS scores. Moreover, no associations were found for IL-1a and IL-1β. Results regarding M2-related cytokines revealed the opposite: high levels of both IL-4 and IL-10 were associated with lower VAS scores. No associations were established for TGF-β. Moreover, the presence of macrophages (CD68) was negatively associated with VAS scores. While M1-related pro-inflammatory cytokines worsen pain symptoms, M2-related anti-inflammatory cytokines alleviate pain symptoms. Nevertheless, the present evidence is limited, and further research on the underlying pathophysiological mechanism in sciatica is required. These slides can be retrieved under Electronic Supplementary Material.

Pedicle screw fixation of thoracolumbar fractures: conventional short segment versus short segment with intermediate screws at the fracture level—a systematic review and meta-analysis

Abstract: Objective: Posterior short-segment fixation (4-screw construct = 4S) is the conventional surgical technique for thoracolumbar fractures. The effect of adding two intermediate pedicle screws at the fractured level (6-screw construct = 6S) is still a matter of debate. This review aims to compare the results between 4 and 6S pedicle screw fixation for thoracolumbar fractures. Methods: A systematic review and meta-analysis were performed. The databases PubMed, Embase and Google Scholar were searched until January 2020. Inclusion criteria were studies comparing 4S and 6S techniques in patients with thoracolumbar fractures. Non-comparative studies and studies without full text were excluded. Cochrane risk of bias was assessed, and the GRADE approach was used to present the quality of evidence. Results: Twenty-seven studies, of which 21 randomized controlled trials, with a total of 1890 patients (940 with 4S and 950 with 6S) were included. Meta-analysis showed that the 6S technique resulted in significantly lower pain scores, better short-term and long-term Cobb angles, less loss of correction and less implant failures. However, longer operation time and more blood loss were seen with the 6S technique. Length of hospital stay, Oswestry Disability Index scores and infections did not differ significantly between the 6S and 4S techniques. Quality of the evidence according to GRADE was moderate to low. Conclusion: In the treatment of thoracolumbar fractures, adding intermediate screws at the fracture level (6S) results in less post-operative pain, better radiological outcomes and less implant failure at the cost of a longer operation time and higher blood loss.

Multiple-rod constructs in adult spinal deformity surgery for pelvic-fixated long instrumentations: an integral matched cohort analysis.

Abstract: Multiple-rod constructs (Multi-Rod: extra rods for additional pillar support) are occasionally used in adult spinal deformity (ASD) surgery. We aimed to compare and analyze the general outcome of multi-rod constructs with a matched two-rod cohort, to better understand the differences and the similitudes. This is a retrospective matched cohort study including patients with ASD that underwent surgical correction with long posterior instrumentation (more than five levels), pelvic fixation and a minimum 1-year follow-up. Matching was considered with demographical data, preoperative radiographical parameters, preoperative clinical status [health-related quality-of-life (HRQoL) scores] and surgical characteristics (anterior fusion, decompression, rod material, osteotomies). Postoperative radiographical and clinical parameters, as well as complications, were obtained. Univariate and multivariate analysis was performed regarding postoperative improvement, group variables comparison and parameters correlation. Thirty-three patients with multi-rod construct and 33 matched with a two-rod construct were selected from a database with 346 ASD-operated patients. Both groups had a significant improvement with surgical management in the radiographical and HRQoL parameters (p < 0.001). Differences between groups for the postoperative radiographical, clinical and perioperative parameters were not significant. Rod breakage was more frequent in the two-rod group (8 vs 4, p = 0.089), as well as the respective revision surgery for those cases (6 vs 1 p = 0.046). Risk factors related to revision surgery were greater kyphosis correction (p = 0.001), longer instrumentation (p = 0.037) and greater sagittal vertical axis correction (p = 0.049). No major disadvantage on the use of multi-rod construct was identified. This supports the benefit of using multi-rod constructs to avoid implant failure. These slides can be retrieved under Electronic Supplementary Material.

Use of augmented reality for image-guided spine procedures

Abstract: Because of its ability to superimpose imaging data on a patient, while anchoring the user’s view to the immediate surroundings, augmented reality (AR) has the potential to dramatically improve the accuracy and reduce the time required for preoperative planning and performance of minimally invasive spine surgeries and procedures Described and reported herein is the direct clinical application of AR navigation on a series of common percutaneous image-guided spine procedures AR, including a “virtual needle” (VN) asset, was used to guide and navigate a total of 18 procedures performed on 10 patients Comparative control data were generated using a phantom model (n = 32) These data are used to determine the accuracy of AR for federal drug administration submissions Optical codes were implemented to allow automatic and real-time registration A manual process was used when the use of optical codes was not available Target error, distance to the target and target size were measured for both phantom and clinical groups Mean errors between the two groups were compared Target error between the control and clinical data sets showed no significant difference Moreover, the distance to the target site and the target size had no effect on target acquisition This data set suggests that AR navigation, utilizing a VN, is an emerging, accurate, valuable additive method for surgical and procedural planning for percutaneous image-guided spinal procedures and has potential to be applied to a broad range of clinical and surgical applications

Percutaneous vertebroplasty and balloon kyphoplasty in the treatment of osteoporotic vertebral fractures: a prospective randomized comparison

Abstract: The purpose of this study is to compare the efficacy and safety of percutaneous vertebroplasty (PVP) and balloon kyphoplasty (BKP) in the treatment of osteoporotic vertebral compression fractures. Patients with osteoporotic vertebral body fractures (T4–L5) were randomized and not blinded to kyphoplasty (n = 69) or vertebroplasty (n = 70). The postoperative pain score (VAS) at 12 months was the primary end point. The radiographic results were evaluated in relation to the resolution of the fracture and the possible onset of further osteoporotic fractures during follow-up. A total of one hundred and thirty-nine patients were eligible for randomization (n = 70 for PVP group and n = 69 for BKP), and twenty-six patients (twenty in the BKP group and six in the PVP group) were excluded. The mean average age of patients was 73 years, and 82% of the patients were females. VAS pain score was significantly reduced after surgery in both groups, and there were no significant differences between the two groups in postoperative VAS score. There was a significant reduction in kyphotic wedge angle and improvement of the sagittal index in both groups, but there was no significant difference between the two groups. There was a significant higher risk incidence of adjacent level fractures in the vertebroplasty group. In terms of clinical outcomes, there were no differences between the two groups. Both showed a significant clinical improvement, vertebral body height restoration and reduction in the kyphotic angle. There was a significant higher risk of adjacent level fractures in the vertebroplasty group.