bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Retrospective Cohort Study Comparing the Safety and Efficacy of Minimally Invasive Versus Open Surgical Techniques in the Treatment of Spinal Metastases
Authors: Hikata Tomohiro , Isogai Norihiro , Shiono Yuta , Funao Haruki , Okada Eijiro , Fujita Nobuyuki , Iwanami Akio , Watanabe Kota , Tsuji Takashi , Nakamura Masaya , Matsumoto Morio , Ishii Ken 
Published: March 2018

Study Design:
A retrospective cohort study.

Objective:
This study was conducted to assess the invasiveness, efficacy, and safety of minimally invasive spine stabilization (MISt) for metastatic spinal tumor patients with short life expectancy.

Summary of Background Data:
Conventional open surgery for metastatic spinal tumors has the disadvantages of significant blood loss, potential infection, damage to back muscles, and extended hospital stays. The minimally invasive spine surgery has changed the treatment of metastatic spinal tumors radically and fundamentally.

Materials and Methods:
We retrospectively reviewed data from 50 consecutive patients registered with the Keio Spine Research Group (KSRG) who underwent posterior palliative surgery for metastatic spinal tumors from January 2009 to June 2015. Of these, 25 patients underwent MISt surgery (M group), and 25 underwent conventional open surgery (C group). The patients were assessed by demographic data, surgical invasiveness, complications, pain improvement, and neurological recovery.

Results:
The 2 groups did not differ significantly in baseline characteristics. The M group had significantly less blood loss (M, 340.1 mL; C, 714.3 mL; P=0.005), less postoperative drainage (M, 136.0 mL; C, 627.0 mL; P<0.001), lower rates of red blood cell transfusion (M, 3 cases; C, 10 cases; P=0.029), and a shorter postoperative period of bed rest (M, 2.0 d; C, 3.6 d; P<0.001), compared with the C group. The perioperative complication rates were significantly lower (P=0.012) in the M group (3 patients, 12%) than in the C group (11 patients, 44%). Neurological deficits and pain improved significantly and comparably in the 2 groups after surgery.

Conclusions:
MISt is a less invasive and effective alternative surgery to conventional open surgery for metastatic spinal tumors. MISt should be considered as a valid option for the treatment of metastatic spinal tumor patients with a short life expectancy.

Level of Evidence:
Level 3.
Prevention and Management of Postoperative Delirium in Elderly Patients Following Elective Spinal Surgery
Authors: Nazemi Alireza K. , Gowd Anirudh K. , Carmouche Jonathan J. , Kates Stephen L. , Albert Todd J. , Behrend Caleb J. 
Published: March 2018

Study Design:
This study is a systematic review.

Objective:
Propose an evidence-based algorithm for prevention, diagnosis, and management of postoperative delirium in geriatric patients undergoing elective spine surgery.

Summary of Background Data:
Delirium is associated with longer stays after elective surgery, increased risk of readmission, and $6.9 billion annually in medical costs. Early diagnosis and treatment of delirium can reduce length of stay (LOS), in-hospital morbidity, and health care costs. After spinal surgery, postoperative delirium increases average LOS to >7 days and is diagnosed in 12.5%–24.3% of geriatric patients. Currently, studies for management of postoperative delirium after elective spinal procedures are not available.

Methods:
A literature review was performed for observational studies, randomized controlled trials, and systematic reviews between 1990 and 2015.

Results:
Risk factors for delirium after elective spinal surgery include age, functional impairment, preexisting dementia, general anesthesia, surgical duration >3 hours, intraoperative hypercapnia and hypotension, greater blood loss, low hematocrit and albumin, preoperative affective dysfunction, and postoperative sleep disorders. Postoperatively, decreasing the use of methylprednisolone and promoting movement with an appropriate orthosis can reduce delirium incidence (P=0.0091). Polypharmacy is an independent risk factor for delirium (P=0.01) and decreasing use of delirium-inducing medications may reduce incidence. The delirium observation screening scale diagnoses and monitors delirium and is rated by nurses as easier to use than the NEECHAM Confusion Scale (P<0.003). Haloperidol is used widely to treat postoperative delirium. Randomized controlled trials show that adding quetiapine results in delirium resolution an average of 3.5 days faster than haloperidol alone (P=0.001) and decreases agitation and LOS (P=0.02; P=0.05).

Conclusions:
An evidence-based algorithm is proposed to prevent, diagnose, and manage postoperative delirium that can be used clinically for geriatric patients undergoing elective spine surgery. Prevention and diagnosis involve efforts from the anesthesiologist and postoperative clinical care team. Treatment may include a therapeutic regimen of low-dose neuroleptic medications as needed.

Level of Evidence:
Level II.
Sensitivity of Computed Tomography Compared With that of Magnetic Resonance Myelography in the Presurgical Diagnosis of Foraminal or Extraforaminal Entrapment at the Lumbosacral Junction
Authors: Lee Sung Ho , Lee Sang-Ho , Kim Soo-Beom , Park Eun Soo , Kim Soo-Nyung , Moon Ki-Hyoung 
Published: March 2018

Study Design:
This is a retrospective analysis.

Objective:
To investigate and compare the sensitivities of computed tomography (CT) and magnetic resonance myelography (MRM) in the presurgical diagnosis of foraminal or extraforaminal entrapment of the L5 nerve.

Summary of Background Data:
CT is more clinically available than MRM. Foraminal or extraforaminal entrapment at the lumbosacral junction may cause L5 radiculopathy but is difficult to diagnose. Asymmetric enlargement of the anterior primary division (APD) of the L5 nerve on preoperative CT and dorsal root ganglion (DRG) swelling and abnormal L5 nerve course on MRM coronal images have been examined in cases of foraminal or extraforaminal L5 nerve entrapment, but have not been compared directly.

Materials and Methods:
Ninety-five patients (mean age 63 y; 28–85 y) with L5 nerve entrapment at the lumbosacral junction who underwent preoperative CT and MRM, and microsurgical decompression by a single surgeon (K.-H.M.) from January 2010 to June 2014 were included. Symptomatic sites were diagnosed by confirming L5 nerve entrapment intraoperatively. Two spinal surgeons independently compared the bilateral APD diameters of the L5 nerve on CT and the L5 nerve courses and DRG swelling on MRM coronal images.

Results:
The interobserver agreement of asymmetric APD swelling on CT and abnormal nerve course and DRG swelling on MRM were excellent (κ=0.808, 0.811, and 0.849, respectively), and the sensitivities were 81%, 84%, and 82% on the right, and 86%, 92%, and 90% on the left sides, respectively. There was no statistically significant difference in the sensitivity between APD swelling on CT and an abnormal nerve course or DRG swelling on MRM on the right (P=1.000 and 0.789) and left (P=0.727 and 1.000) sides, respectively.

Conclusions:
CT has comparable sensitivity to MRM for the presurgical diagnosis of L5 nerve entrapment at the lumbosacral junction.

Level of Evidence:
Level II.
The Influence of Histologic Subtype in Predicting Survival of Lung Cancer Patients With Spinal Metastases
Authors: Kumar Naresh , Tan Kimberly-Anne , Tan Jiong Hao , Zaw Aye S. , Hey Hwee Weng Dennis , Ruiz John , Stone Emily 
Published: March 2018

Study Design:
Retrospective analysis.

Summary of Background Data:
Recent advancements in systemic treatment of lung cancer have significantly improved the survival of patients with certain histolopathologic and molecular subtypes. Existing prognostic scores do not account for this and patients with lung cancer spinal metastases are grouped together as poor prognostic candidates, and consequently, some may be inappropriately denied palliative spine surgery.

Objective:
The objective of the study was to study whether the expected survival in patients with lung cancer spinal metastases is affected by histolopathologic and molecular subtypes in the context of modern systemic therapy.

Materials and Methods:
We retrospectively reviewed all patients with histologically confirmed lung cancer treated for spinal metastases at our institution between 2001 and 2012. Patients’ demographics, histopathologic details, treatment modalities, and survival data were collected. The primary outcome was survival from time of spinal metastases diagnosis. The Cox regression analysis was used to evaluate the influence of tumor histology, molecular profile and treatment modality on survival. The Kaplan-Meier survival analysis was conducted to compare lung cancer subtypes, as well as various treatment regimens.

Results:
Out of 180 patients, 51 underwent surgery for spinal metastases. Female sex (P=0.019), absence of palsy (P=0.023), good Karnofsky performance scores (P<0.001), and non–small cell lung cancer (NSCLC) (P=0.002) were favorable prognostic factors. Patients who received systemic therapy, including tyrosine kinase inhibitors, platinum doublet chemotherapy, or both showed increased survival (P<0.01). The median survival time was 2.40 months [95% confidence interval (CI), 2.13–2.68] in the small cell lung cancer cohort, with no patients surviving past a year; 5.10 months (95% CI, 3.78–6.41) in the NSCLC cohort, with 25.9% 1-year survival; and 13.3 months (95% CI, 2.26–24.40) in adenocarcinoma patients who received both tyrosine kinase inhibitors and platinum doublet therapy, with 50.0% 1-year survival.

Conclusions:
NSCLC, systemic therapy, female sex, absence of palsy and good Karnofsky performance scores are all independent favorable prognostic factors for patients with lung cancer spinal metastases. These should be routinely considered during prognostication.
Posterior Vertebral Column Resection With Intraoperative Manual Retraction for the Treatment of Posttubercular Kyphosis in Upper Thoracic Spine or Cervicothoracic Junction
Authors: Chen Yuqiao , Lü Guohua , Wang Bing , Li Lei , Kuang Lei 
Published: March 2018

Study Design:
This is a case-series.

Objective:
To evaluate the clinical and radiologic outcomes of posterior vertebral column resection (PVCR) for treatment of posttubercular kyphosis in upper thoracic spine and cervicothoracic junction (CTJ).

Summary of Background Data:
Surgical management of severe posttubercular kyphosis in upper thoracic spine or CTJ is challenging. A new technique that combines PVCR and intraoperative manual traction in a single procedure, was developed to maximize the correction rate and minimize the risk of dural buckling and spinal cord injury. However, the safety and effectiveness of the procedure is yet to be established.

Materials and Methods:
Ten patients with upper thoracic or CTJ posttubercular kyphosis, who underwent PVCR with intraoperative manual traction between December 2008 and 2013, were studied retrospectively. Data pertaining to operation time, blood loss, and perioperative complications were collected. Outcomes were evaluated using the visual analog scale; the 12-Item Short Form Health Survey (SF-12), Mental Component Summary, and SF-12 Physical Component Summary. Neurological status was assessed using American Spinal Injury Association (ASIA) impairment scale. Radiologic outcomes including fusion and deformity correction were assessed using plain radiography and computed tomography.

Results:
The average duration of follow-up was 53.6±7.2 months. Average operating time and blood loss were 263±35.3 minutes and 2490±569 mL, respectively. Visual analog scale score for back pain, SF-12 Mental Component Summary, and Physical Component Summary showed significant improvement postoperatively. Kyphosis improved from a preoperative average of 73.6±13.1 degrees to an average of 37.9±8.7 degrees at final follow-up (correction rate: 48.5%). No postoperative neurological deterioration was observed based on the ASIA score. As of the last follow-up, solid fusion was not achieved only in 1 patient.

Conclusions:
PVCR with intraoperative manual traction is a safe and effective procedure for treatment of upper thoracic or CTJ posttubercular kyphosis.

Level of Evidence:
Level 4.
Vertebral Body Hounsfield Units are Associated With Cage Subsidence After Transforaminal Lumbar Interbody Fusion With Unilateral Pedicle Screw Fixation
Authors: Mi Jie , Li Kang , Zhao Xin , Zhao Chang-Qing , Li Hua , Zhao Jie 
Published: March 2018

Objective:
To assess the association between Hounsfield units (HU) measurement and cage subsidence after lumbar interbody fusion.

Background:
Transforaminal lumbar interbody fusion (TLIF) with unilateral fixation becomes a popular treatment modality for lumbar degenerative disease. Cage subsidence is a potentially devastating complication after lumbar interbody fusion with unilateral fixation. Recently, a new technique for assessing bone mineral density using HU values from computed tomography has been proposed. Bone quality is believed to be one of the important factors that cause cage subsidence after TLIF.

Materials and Methods:
Cage subsidence after single-level (L4/5) TLIF with unilateral fixation was prospectively documented at a single institution between 2013 and 2014. Patients with cage subsidence were matched 1:1 to a control cohort without cage subsidence on the basis of age and sex. HU values were measured from the preoperative computed tomography. All patients received computed tomographic scans at a minimum of 6 months postoperatively. Sagittal images were evaluated for evidence of cage subsidence.

Results:
Eighteen patients with cage subsidence were well matched 1:1 to a cohort without cage subsidence and had complete imaging data. The global lumbar HU values were significantly lower in patients with cage subsidence than in the controls (112.4±10.08 vs. 140.2±10.17; P=0.0015). Similarly, a regional assessment of HU across the fusion levels was significantly lower in patients with cage subsidence (113.4±10.47 vs. 127.9±8.13; P=0.0075). The areas under the receiver operating characteristic cure were 0.715 and 0.636 for global and regional assessment, respectively. The best cut-offs for global and regional assessment were 132 (sensitivity: 83.3%; specificity: 61.1%) and 122 (sensitivity: 72.2%; specificity: 55.6%), respectively.

Conclusions:
Lower preoperative HU values is associated with cage subsidence after TLIF with unilateral fixation. HU measurement may be used as a predictor of cage subsidence after unilateral fixation, which also should be incorporated in preoperative planning.
The Role of C2–C7 Angle in the Development of Dysphagia After Anterior and Posterior Cervical Spine Surgery
Authors: Tian Wei , Yu Jie 
Published: March 2018

Study Design:
This is a retrospective clinical study.

Objective:
To analyze the relationship between cervical alignment and the development of dysphagia after anterior and posterior cervical (PC) spine surgery [anterior cervical discectomy and fusion (ACDF), cervical disk replacement (CDR), and PC].

Summary of Background Data:
Dysphagia is a known complication of cervical surgery and may be prolonged or occasionally serious. A previous study showed dysphagia after occipitocervical fusion was caused by oropharyneal stenosis resulting from O–C2 (upper cervical lordosis) fixation in a flexed position. However, there have been few reports analyzing the association between the C2–C7 angle (middle-lower cervical lordosis) and postoperative dysphagia.

Materials and Methods:
In total, 452 patients were reviewed in this study, including 172 patients who underwent the ACDF procedure, 98 patients who had the CDR procedure, and 182 patients who had the PC procedure between June 2007 and May 2010. The presence and duration of postoperative dysphagia were recorded via face-to-face questioning or telephone interview performed at least 1 year after the procedure. Plain cervical radiographs before and after surgery were collected. The O–C2 angle and C2–C7 angle were measured. The change of O–C2 angle and C2–C7 angle were defined as dO–C2 angle=postoperative O–C2 angle−preoperative O–C2 angle and dC2–C7 angle=postoperative C2–C7 angle−preoperative C2–C7 angle. The association between postoperative dysphagia with dO–C2 angle and dC2–C7 angle was studied.

Results:
A total of 12.8% ACDF, 5.1% CDR, and 9.4% PC patients reported dysphagia after cervical surgery. The dC2–C7 angle has considerable impact on postoperative dysphagia. When dC2–C7 angle is >5 degrees, the chance of developing postoperative dysphagia of this patient is significantly greater. The dO–C2 angle, age, sex, body mass index, operative time, blood loss, procedure type, revision surgery, most cephalic operative level, and number of operative levels did not significantly influence the incidence of postoperative dysphagia. No relationship was found between the dC2–C7 angle and the degree of dysphagia.

Conclusions:
Postoperative dysphagia is common after cervical surgery. The dC2–C7 angle may play an important role in the development of dysphagia in both anterior and PC spine surgery. Overenlargement of cervical lordosis should be avoided to reduce the development of postoperative dysphagia.
Anterior Versus Posterior Approaches for Odontoid Fracture Stabilization in Patients Older Than 65 Years
Authors: Patterson Joseph T. , Theologis Alexander A. , Sing David , Tay Bobby 
Published: March 2018

Study Design:
Retrospective cohort analysis.

Objective:
To compare 30-day perioperative clinical outcomes of surgical odontoid stabilization by an anterior or posterior operative approach in elderly patients.

Summary of Background Data:
Surgical stabilization of odontoid fractures is superior to nonoperative management in geriatric patients. How elderly patients with odontoid fractures fare after anterior and posterior approaches, however, is not well defined.

Materials and Methods:
Retrospective review of the prospectively collected American College of Surgeons National Surgical Quality Improvement Program database (2005–2013). Elderly patients (≥65 y) with odontoid fractures who underwent odontoid stabilization through anterior or posterior approaches were identified by International Classification of Diseases 9th Revision/Common Procedure Terminology codes. Exclusion criteria included concomitant subaxial spine surgery, instrumentation noncontiguous with the atlantoaxial interval, and combined approaches. Baseline demographics and perioperative details were compared. Adverse events, mortality, reoperation, discharge, and readmission rates within 30 days of operation were compared using bivariate and multivariate generalized linear regressions.

Results:
One hundred forty-one patients (male—81; female—60; average age: 77.8±6.5 y; anterior approach—48; posterior approach—93) were analyzed. Patients scheduled to have a posterior approach had significantly more nonunions preoperatively and higher body mass indices. Operative times for posterior surgeries were significantly longer. Age, comorbidities, functional dependence, time to surgery, and length of hospital stay were similar between groups. There were no significant differences in the relative risk (RR) of the composite outcome of “any adverse event” after adjusting for differences in baseline characteristics. Patients who underwent an anterior approach were more likely to have an unplanned hospital readmission (RR=8.95; 95% confidence interval, 2.21–36.29; P=0.002) and have significantly more revision operations (RR=19.51; 95% confidence interval, 2.49–152.62; P=0.005) than patients who had a posterior operation.

Conclusions:
An anterior approach for odontoid fracture stabilization in patients ≥65 years old were associated with shorter operative times and greater RRs of unplanned readmissions and revision operations within 30 days of surgery relative to a posterior approach.
The Assessment of Upright Cervical Spinal Alignment Using Supine MRI Studies
Authors: Karabag Hamza , Iplikcioglu Ahmet C. 
Published: March 2018

Study Design:
This is a prospective, single-centre study.

Objective:
The purpose of this study is researching whether there is a correlation or not between the cervical alignment in the examinations of magnetic resonance imaging (MRI) in lying position and the alignment in the cervical direct radiography and whether the cervical alignment in standing position could be estimated or not through MRI measurements in the supine position.

Summary of Background Data:
Cervical spinal alignment is a parameter required for deciding the surgical procedure particularly in patients with cervical myelopathy and deformity. However, cervical alignment angles change according to lying and standing positions. Therefore, the direct standing radiograph is taken as basis for this examination.

Methods
Cervical alignments were measured with 3 different methods with the standing lateral radiographies and lying MRI of 51 patients with cervical disorder.

Results:
A high correlation was found between the measurements in standing and lying positions for the spinal alignments measured through the Cobb angle and posterior tangent method. It was found that standing Cobb angle (in plain graphy)=Cobb angle (in MRI)×0.489+7.13 and posterior tangent angle (in plain graphy)=posterior tangent angle (in MRI)×0.54+9.37.

Conclusions:
It is possible to estimate the spinal alignment in standing position with the measurements of cervical spinal alignment in the MRI at supine position. And this may render having cervical graphy in standing position unnecessary.
Preoperative Risk Factors of C5 Nerve Root Palsy After Laminectomy and Fusion in Patients With Cervical Myelopathy
Authors: Kang Kyung-Chung , Suk Kyung-Soo , Kim Hak-Sun , Moon Seong-Hwan , Lee Hwan-Mo , Seo Jung-Ho , Kim Sung-Min , Jin Sung-Yub , Mella Pierre 
Published: March 2018

Study Design:
A retrospective study.

Objective:
To identify preoperative risk factors causing cervical fifth nerve root palsy (C5 palsy) after laminectomy and fusion (LF).

Summary of Background Data:
It is well known that postoperative C5 palsy is not rare after cervical surgery. Although there remains controversy, C5 palsy is considered to be more common in patients who had LF than in those who had laminoplasty. However, the reason for the higher incidence of C5 palsy in patients with LF has been poorly understood.

Methods:
A total of 70 consecutive patients (mean age: 60.3 y) who had LF due to cervical myelopathy were reviewed. Patients were divided on the basis of the presence (group P) or absence (group N) of C5 palsy. Among various risk factors for C5 palsy from previous reports, 6 risk factors were selected as follows: (1) preoperative low Japanese Orthopedic Association score, (2) postoperatively increased lordosis, (3) low Pavlov ratio, (4) high signal intensity in the cord at C3–C5, (5) anterior protruding mass lesion compressing the spinal cord, and (6) presence of C4–C5 foraminal stenosis. With these factors, the 2 groups were compared by statistical analysis.

Results:
C5 palsy occurred in 10 patients (14.3%). The mean onset time was 3.5 days (range, 1–8 d) and the mean recovery time was 3.4 months (range, 1–7 mo). There were no significant differences in the preoperative Japanese Orthopedic Association score, cervical lordosis, Pavlov ratio, high signal intensity, and anterior protruding mass between the 2 groups (P>0.05). However, C4–C5 foraminal stenosis was found in 80.0% (8/10) in group P and 21.7% (13/60) in group N. There were significant differences between the 2 groups in C4–C5 foraminal stenosis (P=0.004).

Conclusions:
In this study, a high occurrence rate and risk factor for C5 palsy were verified after LF. Among the various factors, C4–C5 foraminal stenosis was the only risk factor for C5 palsy. Preoperative warning for C5 palsy after LF seems to be imperatively necessary, especially in patients with C4–C5 foraminal stenosis.