bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantitative Correction of Cervical Sagittal Deformity in Atlanto-Axial Dislocation
Authors: Liu Zhenlei , Duan Wanru , Wu Hao , Wang Xingwen , Qian Yu , Wang Kai , Guan Jian , Jian Fengzeng , Chen Zan 
Published: March 2019

Study Design.
A mechanism-based reasoning and retrospective cohort study.

Objective.
To establish a quantitative relationship between the change of clivo-axial angle (CXA) and the change of subaxial cervical lordosis (CL) in correction surgery of atlantoaxial dislocation (AAD).

Summary of Background Data.
The evolving understanding of mechanism has dramatically improved the treatment modality of AAD. Cervical sagittal alignment is another important aspect of the surgery, in addition to reduction of odontoid process. However, a quantitative reference for correction surgery has not been established.

Methods.
Frankfort-axial angle (FXA) was introduced. Based on two assumptions, (1) sagittal alignment of the spine aims at keeping horizontal gaze and (2) deformities at craniovertebral junction make little impact on slope of T1 vertebra, we deduced that the change of CXA equaled change of CL (ΔCXA = −ΔCL). We retrospectively reviewed our case cohort to validate this finding with linear regression analysis.

Results.
Sixteen cases (eight male and eight female, mean age 40.4±12.5 yr old) were included. Liner fitting equation for ΔFXA and ΔCXA is y=1.005x (coefficient of determination, R2=0.966; significance of the estimated coefficients P<0.001, t-statistics) and that for ΔCL and ΔCXA is y=−1.023x (R2=0.976, P<0.001). These results support our deduction that ΔCXA = −ΔCL, which can be used as a guidance of quantitative correction of sagittal deformity in AAD.

Conclusion.
Correction of CXA will influence the subaxial cervical lordosis (ΔCXA = −ΔCL) of AAD patients. This equation can serve as a quantitative reference for preoperative planning and intraoperative refining of the correction of cervical sagittal deformity in AAD.

Level of Evidence: 4
Origins, Courses, and Distributions of the Lumbar Arterial Branches in Relation to the Spinal Nerves
Authors: Tatara Yasunori , Nasu Hisayo , Tsutsumi Masahiro , Akita Keiichi 
Published: March 2019

Study Design.
Observational, anatomical, cadaveric study.

Objective.
To investigate the origins, courses, and distributions of the lumbar arterial branches in relation to the spinal nerves using Japanese cadavers.

Summary of Background Data.
Lumbar arterial branches to the spinal nerves can be damaged during posterior lumbar column osteotomy, leading to neurological complications. Spinal cord ischemia via arterial ligation has been reported to be a major cause of neurological complications in anterior thoracolumbar surgery. Although neurological deficits have been considered the most common complications in lumbar pedicle subtraction osteotomy, there is little information on the possible neurological deficits due to spinal nerve ischemia caused by damage to the lumbar arterial branches.

Methods.
In total, 111 lumbar arteries (1 lumbar artery was damaged) from 14 embalmed cadavers (28 sides, L1–L4) were investigated. We examined the branching patterns and measured their diameter and length. Branches to the spinal nerves were classified as follows: radicular branch (Rb), spinal nerve branch (SNb), and plexus branch (Pxb).

Results.
The Rb was identified most frequently at L1 (21.4%) and included the main branch to supply the spinal cord. The SNb diverged from the dorsal branch (59.4%) and was mainly detected at L2 (85.7%) and L3 (85.2%). The Pxb originated from the lumbar artery (56.1%) and was found most frequently at L4 (75%). The Pxb had a larger diameter and a longer length at L3 and L4 than the SNb. Both the L3 and L4 Pxbs were the main blood suppliers to the femoral nerve.

Conclusion.
The L3 and L4 Pxbs mainly supplied the femoral nerve. The Pxb is likely to exist in the medial side of the spinal nerve in the extraforaminal region. Thus, the Pxb should be recognized as a very important arterial branch during operation procedures.

Level of Evidence: 5
Comparative Clinical Effectiveness of Tubular Microdiscectomy and Conventional Microdiscectomy for Lumbar Disc Herniation
Authors: Wang Yinqing , Liang Zeyan , Wu Jianfeng , Tu Songjie , Chen Chunmei 
Published: March 2019

Study Design.
This study is a systematic literature review and meta-analysis.

Objective.
To evaluate the efficacy of tubular microdiscectomy (TMD) compared with conventional microdiscectomy (CMD) for lumbar disc herniation (LDH).

Summary of Background Data.
TMD has developed rapidly due to reduced tissue trauma by minimization of the required access to spine and disc herniation; however, CMD remains the standard of care for this patient group. To date, it remains debatable whether TMD is superior to CMD for LDH.

Methods.
We performed a comprehensive database search of PubMed, EMBASE, and Cochrane Central Register of Controlled Trails for prospective randomized controlled trials (RCTs), through using Medical Subject Headings (MeSH) terms “microdiscectomy,” “tubular microdiscectomy,” “minimally invasive surgery,” and “spinal disease.” The retrieved results were last updated on March 15, 2018. Two independent investigators selected qualified studies, extracted indispensable data, assessed risk of bias of original papers. The Grades of Recommendation, Assessment, Development and Evaluation (GRADE) approach was used to grade quality of evidence. If I
2 >50, the heterogeneity is considerable.

Results.
Four RCT studies (total n = 605), involving 610 individuals with a follow-up period of no less than 12 months, were selected for further review. We assessed these studies as low overall risk of bias. There was low-quality evidence that TMD was superior to CMD considering postoperative Oswestry Disability Index scores (SMD, –3.43, 95% CI, –4.64 to –2.21, P < 0.00001). Compared with CMD, the TMD group exhibited significantly worse Short Form-36 physical function scores (SMD, –4.83, 95% CI, –8.94 to –0.72, P = 0.02). There were no significant differences in the visual analogue scale (P = 0.30), operative time (P = 0.68), dural tear (P = 0.52), and reoperation (P = 0.98).

Conclusion.
The benefits 1 year after TMD were similar to that of CMD. There was no significant difference in the incidence of reoperation and dural tear.

Level of Evidence: 1
Pain Intensity and Fear Avoidance Explain Disability Related to Chronic Low Back Pain in a Saudi Arabian Population
Authors: Alamam Dalyah M. , Moloney Niamh , Leaver Andrew , Alsobayel Hana I. , Mackey Martin G. 
Published: March 2019

Study Design.
A cross-sectional study.

Objective.
The aim of this study was to describe multi-dimensional profiles for people with chronic low back pain (CLBP) and to examine the associations between CLBP-related disability and individual, psychosocial and physical factors in a Saudi population.

Summary of Background Data.
CLBP-related disability is a multidimensional phenomenon. There is growing interest in exploring factors associated with CLBP-related disability in Saudi Arabia but research is limited in comparison to other countries.

Methods.
Participants completed questionnaires covering demographics, pain intensity, back beliefs, fear avoidance, psychological distress, and physical activity. Oswestry Disability Index (ODI) was used to measure disability. Participants also performed a standardized sequence of physical performance tests and a Pain Behavior Scale was used to evaluate pain behaviors during performance of these tests. The relationships between disability and all variables were explored using univariate and multivariate regression analyses.

Results.
One hundred and fifteen participants were included, 63% of whom were female. Participants demonstrated moderate disability (mean [SD]: 26.6 [13.5]). The mean (SD) back beliefs score was 28.6 (7.3). Mean depression, anxiety, and stress (DASS 21) scores indicated mild distress; however, 26% to 39% scored in the moderate to severe range for at least one subscale. In univariate analyses, pain intensity and fear avoidance beliefs (physical activity and work) were moderately associated with disability (r = 0.56, 0.49, 0.52, respectively, P < 0.001), with all other factors demonstrating weak association. Multivariate regression revealed that pain intensity, fear avoidance beliefs, psychological distress, and participants’ age were all found to be associated with disability, accounting for 52.9% (adjusted R

2
= 0.529) of variability.

Conclusion.
This study provides a unique insight into the clinical profile of people with CLBP in a Saudi Arabian population. Pain and psychosocial factors were significantly associated with disability. This study supports the contention that CLBP-related disability is a multifactorial biopsychosocial condition across different cultures.

Level of Evidence: 3
A Novel Technique for Total En bloc Spondylectomy of the Fifth Lumbar Tumor Through Posterior-Only Approach
Authors: Yang Xinghai , Yang Jian , Jia Qi , Zhong Nanzhe , Jiao Jian , Hu Jinbo , Peng Dongyu , Liu Weibo , Wan Wei , Xiao Jianru 
Published: March 2019

Study Design.
A retrospective study.

Objective.
To describe a new surgical technique for total en bloc spondylectomy (TES) of the fifth lumbar (L5) tumor and evaluate the efficacy and safety of this new technique.

Summary of Background Data.
TES has been considered an optimal treatment for tumor, including certain spinal tumors, but it requires a combined posterior–anterior approach, which is often complicated by a long operation time, considerable blood loss and severe trauma.

Methods.
Seven patients with primary or solitary metastatic tumors of L5 were treated with this new technique in our center between March 2014 and November 2017. The critical points were fabrication of the iliac graft, dissection, resection, and reconstruction. Other parameters including surgical time, blood loss, complications, pre- and postoperative neurological function, tumor control, and overall survival (OS) were presented and analyzed.

Results.
All the included patients received one stage TES. The mean surgical time was 365.7 minutes with an average blood loss of 2514.3 mL. No serious perioperative complication was observed or reported during the mean follow-up period of 27.4 months. Wound disruption occurred in one patient and numbness of the left lower limb in another, but both recovered rapidly after appropriate management. Adventitial avulsion of the abdominal aorta occurred during dissection in one patient. Two patients died during the follow-up period due to advanced malignancy. One patient was alive but developed a newly diagnosed thoracolumbar tumor in 40 months. The other four patients recovered well without evidence of disease. All patients were able to walk independently 3 to 4 weeks after operation, with satisfied fusion of the iliac grafts in a mean period of 6.7 months after operation. No evidence of internal fixation failure occurred.

Conclusion.
This new technique offers satisfactory surgical exposure, total en bloc spondylectomy, reliable reconstruction, and good tumor control for certain L5 tumors through the posterior-only approach.

Level of Evidence: 4
Gadolinium Enhancement Is Not Associated With Disc Inflammation in Patients With Sciatica
Authors: Djuric Niek , Yang Xiaoyu , Barzouhi Abdelilah el , Ostelo Raymond W.J.G. , Duinen Sjoerd G. van , Nijeholt Geert J. Lycklama à , van der Kallen Bas F.W. , Peul Wilco C. , Vleggeert-Lankamp Carmen L.A. 
Published: March 2019

Study Design.
Retrospective observational histological study.

Objective.
To evaluate the reliability of gadolinium enhancement as a marker for inflammation by associating gadolinium enhancement findings with the degree of inflammation as measured by macrophage infiltration in disc material retrieved during disc surgery in patients with sciatica.

Summary of Background Data.
Disc inflammation often occurs in sciatica patients, a noninvasive tool that is used to assess disc inflammation is Gadolinium enhanced MR imaging.

Methods.
Disc tissue was retrieved from patients in the Sciatica trial (N = 119), a multicenter randomized controlled trial in patients with sciatica. Disc tissue was embedded in paraffin and stained with hematoxylin and CD68. Tissue samples were categorized as mild (0–10 macrophages/cm2), moderate (10–100 macrophages/cm2), and considerable (>100 macrophages/cm2) inflammation. Of the 119 MRIs, 96 were additionally performed with contrast-enhanced gadolinium.

Results.
Seventy-four patients showed gadolinium enhancement of the disc herniation and 26 of the nerve root. Degree of inflammation by macrophages was not associated with gadolinium enhancement of nerve roots or herniated discs. These results did not change if the patient groups with and without Modic type 2 changes were evaluated separately. Furthermore, no associations were observed between gadolinium enhancement and presence of Modic type 2 changes.

Conclusion.
This study found gadolinium enhanced MRI findings to be unreliable as an indicator for inflammation of disc herniation or nerve root in patients with sciatica.

Level of Evidence: 2
AMP-Activated Protein Kinase Activation in Dorsal Root Ganglion Suppresses mTOR/p70S6K Signaling and Alleviates Painful Radiculopathies in Lumbar Disc Herniation Rat Model
Authors: Liu Yuantong , Li Jianmin , Li Hao , Shang Yue , Guo Yan , Li Zhenzhong , Liu Zhen 
Published: March 2019

Study Design.
Animal experiment: a rat model of lumbar disc herniation (LDH) induced painful radiculopathies.

Objective.
To investigate the role and mechanism of AMP-activated protein kinase (AMPK) in dorsal root ganglia (DRG) neurons in LDH-induced painful radiculopathies.

Summary of Background Data.
Overactivation of multiple pain signals in DRG neurons triggered by LDH is crucial to the development of radicular pain. AMPK is recognized as a cellular energy sensor, as well as a pain sensation modulator, but its function in LDH-induced pain hypersensitivity remains largely unknown.

Methods.
The LDH rat model was established by autologous nucleus pulposus transplantation into the right lumbar 5 (L5) nerve root. At different time points after AMPK agonist metformin (250 mg/kg/d) or mammalian target of rapamycin (mTOR) inhibitor rapamycin (5 mg/kg) intraperitoneal administration, thermal and mechanical sensitivity were evaluated by measuring paw withdrawal latency (PWL) and 50% paw withdrawal thresholds (PWT). The levels of AMPK, mTOR, and p70S6K phosphorylation were determined by Western blot. We also investigated the proportion of p-AMPK positive neurons in the right L5 DRG neurons using immunofluorescence.

Results.
LDH evoked persistent thermal hyperalgesia and mechanical allodynia on the ipsilateral paw, as indicated by the decreased PWL and 50% PWT. These pain hypersensitive behaviors were accompanied with significant inhibition of AMPK and activation of mTOR in the associated DRG neurons. Pharmacological activation of AMPK in the DRG neurons not only suppressed mTOR/p70S6K signaling, but also alleviated LDH-induced pain hypersensitive behaviors.

Conclusion.
We provide a molecular mechanism for the activation of pain signals based on AMPK-mTOR axis, as well as an intervention strategy by targeting AMPK-mTOR axis in LDH-induced painful radiculopathies.

Level of Evidence: N/A
Ischemic Optic Neuropathy Following Spine Surgery
Authors: Goyal Anshit , Elminawy Mohamed , Alvi Mohammed Ali , Long Timothy R. , Chen John J. , Bradley Elizabeth , Freedman Brett A. , Bydon Mohamad 
Published: March 2019

Study Design.
Case–control analysis and systematic literature review.

Objective.
To illustrate the prognosis and perioperative risk factors associated with this condition.

Summary of Background Data.
Ischemic optic neuropathy (ION) is the most common pathological diagnosis underlying postoperative vision loss. It comes in two primary forms—anterior (AION)—affecting the optic disc or posterior (PION) affecting the optic nerve proximal to the disc. Spine surgery remains one of the largest sources of acute perioperative visual loss.

Methods.
We performed a 1:4 case–control analysis (by age and year of surgery) for patients with ION and those who didn’t develop ION following spine surgery at our institution. A systematic literature search of Medline, Embase, Scopus from inception to September 2017 as also performed.

Results.
We identified 12 cases from our institution. Comparison to 48 matched controls revealed fusion, higher number of operative levels, blood loss, and change in hemoglobin, hematocrit to be significantly associated with ION. Majority were diagnosed with PION (83%, 10/12) and had bilateral presentation (75%, 9/12). Only 30% patients (3/10) demonstrated improvement in visual acuity while the rest remained either unchanged (40%, 4/10) or worsened (20%, 2/10) at last follow-up. Literature review identified 182 cases from 42 studies. Posterior ischemic optic neuropathy (PION) was found in 58.7% (114/194) of cases, anterior ischemic optic neuropathy (AION) in 17% (33/19) and unspecified ION in 24% (47/194). PION was associated with higher odds of severe visual deficit at immediate presentation (odds ratio [OR]: 6.45, confidence interval [CI]: 1.04–54.3, P = 0.04) and last follow-up.

Conclusion.
PION is the most common cause of vision loss following spine surgery and causes more severe visual deficits compared with AION. Prone spine surgery especially multi-level fusions with longer operative time, higher blood loss, and intraoperative hypotension are most associated with the development of this devastating complication.

Level of Evidence: 3
ERRFI1 Inhibits Proliferation and Inflammation of Nucleus Pulposus and Is Negatively Regulated by miR-2355-5p in Intervertebral Disc Degeneration
Authors: Guo Yusong , Tian Lijun , Liu Xing , He Yinxi , Chang Songtao , Shen Yong 
Published: March 2019

Study Design.

In vivo and in vitro studies of the role of miR-2355-5p and its possible targets in intervertebral disc degeneration (IVDD).

Objective.
To elucidate the regulatory role of miR-2355-5p in IVDD and the underlying mechanisms.

Summary of Background Data.
IVDD, which is caused by multiple factors, is the main cause of lower back pain with or without extremity pain. However, the underlying cellular mechanisms of IVDD pathogenesis are not well elucidated. Cell hyper-proliferation, inflammation, and epidermal growth factor receptor activation have been implicated in IVDD. Up-regulated miR-2355-5p level was identified to associate with IVDD. ERRFI1 (the product of mitogen-inducible gene 6 [MIG6]) was known to inhibit epidermal growth factor receptor activation.

Methods.
We monitored the expression of miR-2355-5p and ERRFI1 in IVDD tissues and lipopolysaccharides (LPS)-treated nucleus pulposus (NP) cells. We explored the effects of ERFFI1 on NP cells proliferation and LPS-induced pro-inflammatory cytokines production. We searched the targets of miR-2355-5p and explored the effects of miR-2355-5p on NP cells proliferation and cytokines production.

Results.
We identified the up-regulation of miR-2355-5p and down-regulation of ERFFI1 in IVDD samples and LPS-treated NP cells. ERFFI1 inhibited NP cells proliferation and LPS-induced pro-inflammatory cytokine production. MiR-2355-5p targeted ERFFI1 and negatively regulated ERFFI1 expression. MiR-2355-5p regulated IVDD by targeting ERFFI1.

Conclusion.
MiR-2355-5p negatively regulated ERFFI1 and prevented the effects of ERRFI1 on inhibiting NP cells proliferation and inflammation.

Level of Evidence: N/A
Sagittal Alignment Outcomes in Lordotic Cervical Spine
Authors: Liang Guoyan , Liang Changxiang , Zheng Xiaoqing , Xiao Dan , Zeng Shixing , Yin Dong , Zhan Shiqiang , Ye Juntong , Liu Xiao , Chang Yunbing 
Published: March 2019

Study Design.
A prospective cohort study.

Objective.
To compare the radiological outcomes between three-level anterior cervical discectomy and fusion (ACDF) and plate-only open-door laminoplasty (LAMP) in patients with lordotic cervical spine.

Summary of Background Data.
Both three-level ACDF and LAMP are important surgical methods for multilevel cervical spondylotic myelopathy, but the cervical sagittal alignment outcomes and the lordosis preserving abilities between the two specific approaches have not been carefully compared.

Methods.
Sixty patients, all of whom had lordotic cervical spines and underwent three-level ACDF (n = 22) or LAMP (n = 38) for the treatment of multilevel cervical spondylotic myelopathy, were prospectively studied. Upright neutral cervical lateral radiographs were assessed preoperatively, at 3 days after surgery, and at the last follow-up (1.5 years). The primary radiological outcomes are C2–7 Cobb angle, and the secondary outcomes include C2–7 sagittal vertical axis , disc height, Harrison angle, and Ishihara index. The relationship between preoperative parameters and follow-up outcomes were assessed.

Results.
Preoperative cervical sagittal alignment parameters were similar between the two groups. Patients in the ACDF group obtained larger C2–7 Cobb angles than those the LAMP group early after surgery. However, the lordosis in the ACDF group decreased significantly during follow-up, leading to similar outcomes between the two groups. The lordosis-preserving ability of ACDF is significantly poorer than that of LAMP. Secondary radiological parameters also showed similar trends. In both groups, the preoperated Ishihara index was significantly related to follow-up C2–7 Cobb angles. For patients with Ishihara index less than 20, ACDF is more likely to produce a larger C2–7 Cobb angled at the time of follow-up.

Conclusion.
In patients with lordotic cervical spine, the sagittal alignment outcomes of the two approaches were similar, and the lordosis-preserving ability was poorer in ACDF. Further research should focus on the factors related to the lordosis-preserving ability of multilevel ACDF.

Level of Evidence: 3
Sagittal Alignment With Downward Slope of the Lower Lumbar Motion Segment Influences Its Modes of Failure in Direct Compression
Authors: Sapiee Nurul Haiza , Thambyah Ashvin , Robertson Peter A. , Broom Neil D. 
Published: March 2019

Study Design.
Microstructural investigation of compression-induced herniation of ovine lumbar discs with and without added component of anterior-inferior slope.

Objective.
Does increased shear arising from a simulated component of motion segment slope imitating sacral slope weaken the lateral annulus and increase risk of overt herniation at this same region.

Summary of Background Data.
An increase in sacral slope secondary to lordosis and pelvic incidence increases shear stresses at the lumbosacral junction and has been associated with an increase in spondylolisthetic disorders and back injury. The small component of forward shear induced when a segment is compressed in flexion is suggested to cause differential recruitment of the lateral annular fibers leading to its early disruption followed by intra-annular nuclear tracking to the posterolateral/posterior regions. However, the influence of even greater forward shear arising from the added component of slope seen where pelvic incidence and lumbar lordosis are increased in the lower lumbar spine is less understood.

Methods.
Ovine motion segments were compressed at 40 mm/min up to failure; 9 with a horizontal disc alignment and 26 with a segment slope of 15° and then analyzed structurally.

Results.
All the horizontal discs failed (11.8 ± 2.4 kN) via vertebral fracture without any evidence of soft tissue failure even in the lateral aspects of the discs. The increased forward shear resulting from the slope decreased the failure load (6.4 ± 1.6 kN). The sloping discs mostly suffered mid-span, noncontinuous disruption of the lateral annulus with some extruding nuclear material directly from these same lateral regions.

Conclusion.
The increased level of forward shear generated in moderately sloping lumbar segments when compressed was abnormally damaging to the lateral regions of the disc annulus. This is consistent with the view that shear differentially loads the oblique-counter oblique fiber sets in the lateral annulus, increasing its vulnerability to early disruption and overt herniation.

Level of Evidence: N/A