bluuebunny/crossref_metadata_2025_split huggingface dataset:
Management of neurotrauma by surgeons and orthopedists in a military operational setting
Authors: Mauer Uwe Max , Kunz Ulrich 
Published: February 2011

There is a considerable discrepancy between the potential demand for neurosurgeons and the actual availability of such specialists not only in civilian settings but even more so in military operational environments.
For this reason, the Department of Neurosurgery at the German Armed Forces Hospital in Ulm conducts courses for surgeons and orthopedists on the management of patients with neurotrauma. Twelve such courses have already taken place. Each course lasts 1 week. Participants can expect to gain the theoretical knowledge and practical skills they need to provide initial surgical care for patients with traumatic brain injuries and/or spinal trauma. Surgical techniques are practiced above all in pig and human cadavers. At the end of the course, participants with previous surgical knowledge should be able to independently perform a craniotomy, from the planning of the procedure to the closure of the wound. Former course participants have successfully used their neurosurgical knowledge in countries of deployment where they managed patients during teleconsultation sessions and helped repatriate, or even provided surgical treatment to, patients with traumatic brain injuries. In these situations, it was particularly helpful when the physician deployed abroad and the neurosurgeon in Germany knew each other personally. In the future, efforts will be made to combine telemedicine and neuronavigation in an attempt to further improve direct support for physicians under military deployment conditions.
Resident learning curve for minimal-access transforaminal lumbar interbody fusion in a military training program
Authors: Neal Chris J. , Rosner Michael K. 
Published: February 2011

Object
Minimal-access transforaminal lumbar interbody fusion (TLIF) has gained popularity as a method of achieving interbody fusion via a posterior-only approach with the aim of minimizing injury to adjacent tissue. While many studies have reported successful outcomes, questions remain regarding the potential learning curve for successfully completing this procedure. The goal of this study, based on a single resident's experience at the only Accreditation Council for Graduate Medical Education–approved neurosurgical training center in the US military, was to determine if there is in fact a significant learning curve in performing a minimal-access TLIF.

Methods
The authors retrospectively reviewed all minimal-access TLIFs performed by a single neurosurgical resident between July 2006 and January 2008. Minimal-access TLIFs were performed using a tubular retractor inserted via a muscle-dilating exposure to limit approach-related morbidity. The accuracy of screw placement and operative times were assessed.

Results
A single resident/attending team performed 28 minimal-access TLIF procedures. In total, 65 screws were placed at L-2 (1 screw), L-3 (2 screws), L-4 (18 screws), L-5 (27 screws), and S-1 (17 screws) from the resident's perspective. Postoperative CTs were reviewed to determine the accuracy of screw placement. An accuracy of 95.4% (62 of 65) properly placed screws was noted on postoperative imaging. Two screws (at L-5 in the patient in Case 17 and at S-1 in the patient in Case 9) were lateral, and no revision was needed. One screw (at L-4 in Case 24) was 1 mm medial without symptoms or the need for revision. In evaluating the operative times, 2 deformity cases (Grade III spondylolisthesis) were excluded. The average operating time per level in the remaining 26 cases was 113.25 minutes. The average time per level for the first 13 cases was 121.2 minutes; the amount of time decreased to 105.3 minutes for the second group of 13 cases (p = 0.25).

Conclusions
In summary, minimal-access TLIF can be safely performed in a training environment without a significant complication rate due to the expected learning curve.
Multilevel cervical arthroplasty with artificial disc replacement
Authors: Cardoso Mario J. , Rosner Michael K. 
Published: February 2011

Object
In this study, the authors review the technique for inserting the Prestige ST in a contiguous multilevel cervical disc arthroplasty in patients with radiculopathy and myelopathy. They describe the preoperative planning, surgical technique, and their experience with 10 patients receiving a contiguous Prestige ST implant. They present contiguous multilevel cervical arthroplasty as an alternative to multilevel arthrodesis.

Methods
After institutional board review approval was obtained, the authors performed a retrospective review of all contiguous multilevel cervical disc arthroplasties with the Prestige ST artificial disc between August 2007 and November 2009 at a single institution by a single surgeon. Clinical criteria included patients who had undergone a multilevel cervical disc arthroplasty performed for radiculopathy and myelopathy without the presence of a previous cervical fusion. Between August 2007 and November 2009, 119 patients underwent cervical arthroplasty. Of the 119 patients, 31 received a Hybrid construct (total disc resection [TDR]–anterior cervical decompression and fusion [ACDF] or TDR-ACDF-TDR) and 24 received a multilevel cervical arthroplasty. The multilevel cervical arthroplasty group consisted of 14 noncontiguous and 10 contiguous implants. This paper examines patients who received contiguous Prestige ST implants.

Results
Ten men with an average age of 45 years (range 25–61 years) were treated. Five patients presented with myelopathy, 3 presented with radiculopathy, and 2 presented with myeloradiculopathy. Twenty-two 6 × 16–mm Prestige ST TDRs were implanted. Six patients received 2-level Prestige ST implants. Five patients received TDRs at C5–6 and C6–7, and 1 patient received TDRs at C3–4 and C4–5. One patient received a TDR at C3–4, C5–6, and C6–7 where C4–5 was a congenital block vertebra. Three patients (2 with 3-level disease and 1 with 4-level disease) received contiguous Prestige ST implants as well as a Prevail ACDF as part of their constructs. The mean clinical and radiographic follow-up was 12 months. There has been no case of screw backout, implant dislodgment, progressive kyphosis, formation of heterotopic bone, evidence of pseudarthrosis at the Prevail levels, or development of symptomatic adjacent level disease.

Conclusions
Multilevel cervical arthroplasty with the Prestige ST is a safe and effective alternative to fusion for the management of cervical radiculopathy and myelopathy.
Does the Wilson frame assist with optimizing surgical exposure for minimally invasive lumbar fusions?
Authors: Cardoso Mario J. , Rosner Michael K. 
Published: February 2011

Object
Minimally invasive lumbar spine surgery has dramatically evolved over the last decade. Minimally invasive techniques and transforaminal lumbar interbody fusion (TLIF) often require a steep learning curve. Surgical techniques require pre-positioning the patient in maximal kyphosis to optimize visualization of the disc space and prevent unnecessary retraction of neural structures. The authors describe their experience in validating the surgical technique recommendation of Wilson frame–induced kyphosis.

Methods
Over the past 6 months, data obtained in 20 consecutive patients (40 total levels) undergoing minimally invasive TLIF were reviewed. In each patient, preincision intraoperative radiographs were reviewed at L4–5 and L5–S1 with the patient on a Wilson frame in maximal lordosis and then in maximal kyphosis. The change in disc space angle at L4–5 and L5–S1 after changing from maximal lordosis to maximal kyphosis was reviewed. Descriptive statistics were calculated for sagittal plane angular measures at L4–5 and L5–S1 in lordosis and kyphosis, including absolute differences and percentage of change between positions. Inferential statistics were calculated using paired t-tests with α= 0.05.

Results
Twenty patients underwent single- or multilevel minimally invasive TLIF. Inducing kyphosis with the Wilson frame aided in optimizing exposure and decreasing the need for neural structure retraction. Both L4–5 and L5–S1 showed statistically significant (p < 0.001) and clinically meaningful changes with increased segmental flexion in the kyphotic position. At L4–5 the mean increase in flexion was 4.5° (95% CI 2.9–6.0°), representing an average 47% change. The mean increase in flexion at L5–S1 was 3.2° (95% CI 2.3–4.2°), representing an average 20.8% change. In lordosis the mean angle at L4–5 was 10.6 ± 4.4° and at L5–S1 was 17 ± 7.0°. In kyphosis the mean angle at L4–5 was 6.1 ± 4.5° and at L5–S1 was 13.8 ± 6.5°. Additionally, there was a statistically significant difference (p < 0.05) in percentage of change between the 2 levels, with L4–5 showing a greater change (27% more flexion) between positions, but the absolute mean difference between the levels was small (1.3°).

Conclusions
Minimally invasive TLIF is challenging and requires a significant learning curve. The recommended surgical technique of inducing kyphosis with the Wilson frame prior to incision significantly optimizes exposure. The authors' experience demonstrates that this technique is essential when performing minimally invasive lumbar spinal fusions.
A systematic review of randomized trials on the effect of cervical disc arthroplasty on reducing adjacent-level degeneration
Authors: Botelho Ricardo Vieira , Moraes Osmar José dos Santos , Fernandes Gustavo Alberto , Buscariolli Yuri dos Santos , Bernardo Wanderley Marques 
Published: February 2011

Object
Anterior cervical discectomy and fusion had been considered a safe and effective procedure for radiculopathy and myelopathy in the cervical spine, but degeneration in adjacent spinal levels has been a problem in some patients after fusion. Since 2002, cervical disc arthroplasty has been established as an alternative to fusion. The objective of this study was to review data concerning the role of cervical arthroplasty in reducing adjacent-level degeneration.

Methods
A systematic review was performed using the MEDLINE, EMBASE, Cochrane, and LILACS databases, focusing on a structured question involving the population of interest, types of intervention, types of control, and outcomes studied.

Results
No study has specifically compared the results of arthroplasty with the results of fusion with respect to the rate of postoperative development of adjacent-segment degenerative disease. One paper described a rate for adjacent-level surgery. The level of evidence of that paper was classified 2b, and although its authors found a statistically significant between-groups difference (arthroplasty vs fusion) using log-rank analysis, re-analysis according to number needed to treat (in the current paper) did not reveal statistical significance.

Conclusions
Adjacent-level degeneration has not been adequately studied in a review of the available randomized controlled trials on this topic, and there is no clinical evidence of reduction in adjacent-level degeneration with the use of cervical arthroplasty.
The predictive value of the baseline Oswestry Disability Index in lumbar disc arthroplasty
Authors: Deutsch Harel 
Published: February 2011

Object
The goal of the study was to determine patient factors predictive of good outcome after lumbar disc arthroplasty. Specifically, the paper examines the relationship of the preoperative Oswestry Disability Index (ODI) to patient outcome at 1 year.

Methods
The study is a retrospective review of 20 patients undergoing a 1-level lumbar disc arthroplasty at the author's institution between 2004 and 2008. All data were collected prospectively. Data included the ODI, visual analog scale scores, and patient demographics.

Results
All patients underwent a 1-level disc arthroplasty at L4–5 or L5–S1. The patients were divided into 2 groups based on their baseline ODI. Patients with an ODI between 38 and 59 demonstrated better outcomes with lumbar disc arthroplasty. Only 1 (20%) of 5 patients with a baseline ODI higher than 60 reported a good outcome. In contrast, 13 (87%) of 15 patients with an ODI between 38 and 59 showed a good outcome (p = 0.03). The negative predictive value of using ODI > 60 is 60% in patients who are determined to be candidates for lumbar arthroplasty.

Conclusions
Lumbar arthroplasty is very effective in some patients. Other patients do not improve after surgery. The baseline ODI results are predictive of outcome in patients selected for lumbar disc arthroplasty. A baseline ODI > 60 is predictive of poor outcome. A high ODI may be indicative of psychosocial overlay.
Efficacy and limitations of intraoperative spinal cord monitoring using nasopharyngeal tube electrodes
Authors: Yamamoto Naoya , Kobashi Hiroe , Shiba Masahiro , Itoh Tatsuo 
Published: February 2011

ObjectMotor evoked potentials are widely used for intraoperative spinal cord monitoring. However, there are problems with anesthetic constraints and high trial-by-trial variability of compound muscle action potential amplitude in muscle motor evoked potential monitoring. It is difficult to determine when to warn the surgeon of an occurrence of spinal cord risk. A method of estimation for motor function in the spinal cord has not been established. To monitor spinal cord function with reliable evoked potentials, including the upper cervical spinal cord and the ventral spinal cord, the authors developed a nasopharyngeal tube electrode that can be placed in front of the upper and ventral cervical spinal cord. The purpose of this study was to investigate the origins and pathways of descending or ascending spinal cord evoked potentials (SCEPs) elicited with this electrode, and the usefulness and limitations of this method.MethodsA nasopharyngeal tube electrode was inserted into the nostril. A catheter electrode was placed in the epidural or subarachnoid space at the thoracic spine. Ventral SCEP was recorded from the thoracic spinal cord after transpharyngeal stimulation, and dorsal SCEP was recorded with the nasopharyngeal electrode after thoracic spinal cord stimulation. There was no restriction of anesthetic technique in recording. When the amplitude of either of the SCEPs declined to 80% of the baseline, a warning was provided to the surgeon during the observed operative procedure. At the end of surgery, less than 50% or more than 30% of the baseline amplitude was considered a significant change in both SCEPs. The sensitivity and specificity for both SCEPs to detect neurological deterioration were calculated.ResultsThe electrode provided noninvasive access to the ventral cervicomedullary junction. The SCEPs showed stable responses. A response change was only observed in situations involving a risky procedure for the spinal cord. Ventral SCEPs showed high sensitivity (73.1%) for identifying patients with new neurological deficits or an exacerbation of preexisting neurological deficits after surgery, but dorsal SCEPs showed lower sensitivity (46.1%) in the total number of cases. Both SCEPs showed high specificities. The sensitivities of ventral SCEP, dorsal SCEP, and either SCEP were 100.0%, 50.0%, and 100.0% for the upper cervical spinal cord, 33.3%, 0%, and 55.6% for the lower cervical spinal cord, and 77.8%, 64.7%, and 88.2% for the thoracic spinal cord.ConclusionsCombined recording of both SCEPs estimated the ventral and dorsal white matter function in the spinal cord. Measuring the SCEPs with the nasopharyngeal electrode can be another useful approach for upper cervical and thoracic spinal cord monitoring. Ventral SCEP was more reliable for monitoring postoperative spinal cord function than dorsal SCEP. Ventral SCEP does not estimate the gray matter and spinal root functions in the lower cervical spinal cord.
Complications in spine surgery
Authors: Nasser Rani , Yadla Sanjay , Maltenfort Mitchell G. , Harrop James S. , Anderson D. Greg , Vaccaro Alexander R. , Sharan Ashwini D. , Ratliff John K. 
Published: February 2011

ObjectThe overall incidence of complications or adverse events in spinal surgery is unknown. Both prospective and retrospective analyses have been performed, but the results have not been critically assessed. Procedures for different regions of the spine (cervical and thoracolumbar) and the incidence of complications for each have been reported but not compared. Authors of previous reports have concentrated on complications in terms of their incidence relevant to healthcare providers: medical versus surgical etiology and the relevance of perioperative complications to perioperative events. Few authors have assessed complication incidence from the patient's perspective. In this report the authors summarize the spine surgery complications literature and address the effect of study design on reported complication incidence.MethodsA systematic evidence-based review was completed to identify within the published literature complication rates in spinal surgery. The MEDLINE database was queried using the key words “spine surgery” and “complications.” This initial search revealed more than 700 articles, which were further limited through an exclusion process. Each abstract was reviewed and papers were obtained. The authors gathered 105 relevant articles detailing 80 thoracolumbar and 25 cervical studies. Among the 105 articles were 84 retrospective studies and 21 prospective studies. The authors evaluated the study designs and compared cervical, thoracolumbar, prospective, and retrospective studies as well as the durations of follow-up for each study.ResultsIn the 105 articles reviewed, there were 79,471 patients with 13,067 reported complications for an overall complication incidence of 16.4% per patient. Complications were more common in thoracolumbar (17.8%) than cervical procedures (8.9%; p < 0.0001, OR 2.23). Prospective studies yielded a higher incidence of complications (19.9%) than retrospective studies (16.1%; p < 0.0001, OR 1.3). The complication incidence for prospective thoracolumbar studies (20.4%) was greater than that for retrospective series (17.5%; p < 0.0001). This difference between prospective and retrospective reviews was not found in the cervical studies. The year of study publication did not correlate with the complication incidence, although the duration of follow-up did correlate with the complication incidence (p = 0.001).ConclusionsRetrospective reviews significantly underestimate the overall incidence of complications in spine surgery. This analysis is the first to critically assess differing complication incidences reported in prospective and retrospective cervical and thoracolumbar spine surgery studies.
Impact of cordectomy as a treatment option for posttraumatic and non-posttraumatic syringomyelia with tethered cord syndrome and myelopathy
Authors: Ewelt Christian , Stalder Susanne , Steiger Hans-Jakob , Hildebrandt Gerhard , Heilbronner Raoul 
Published: February 2011

Object
Spinal cordectomy has recently become more important in the treatment of end-stage posttraumatic or postoperative syringomyelia and arachnopathy as a last resort to manage ascending neurological dysfunction, spasticity, and pain in paraplegic patients. The aim in this study was to confirm a clinical benefit in strict indications for cordectomy.

Methods
Between February 2000 and September 2007, 15 spinal cordectomies were performed at the Department of Neurosurgery, Cantonal Hospital, St. Gallen. Indications for treatment were end-stage myelopathies caused by syringomyelia, tethered cord syndrome, and arachnopathy with progressive spasticity and pain or progressive upper-level neurological deficits related to the tethered cord syndrome. All patients had severe motor and sensory deficits with no residual voluntary function below the affected level.

Results
Fourteen of 15 patients showed stabilization or even an improvement in motor and sensory function. Four patients suffered from progressive spasticity and 3 from deterioration due to pain. There were no other adverse surgical events.

Conclusions
Cordectomy can be a useful instrument to preserve functions of the upper extremities and to improve spasticity and pain in patients with severe myelopathy and tethered cord, syringomyelia, or arachnopathy of various etiologies.
Potentiation of neurite outgrowth and reduction of apoptosis by immunosuppressive agents: implications for neuronal injury and transplantation
Authors: Sheehan Jason , Eischeid Anne , Saunders Randi , Pouratian Nader 
Published: February 2011

Object
Immunosuppressive agents are believed to play a role in recovery from spinal cord injury, but the underlying mechanisms by which neuronal function is improved by these agents are poorly understood. In this study, the authors evaluate the effect of immunosuppressive medications on neurite outgrowth and cell survival after a pharmacologically induced injury.

Methods
Differentiated human neuroblastoma SH-SY5Y cells were injured using the calcium agonist thapsigargin. After cellular injury, neurite outgrowth in the presence or absence of immunosuppressive agents was measured. Apoptosis was quantified with the aid of a terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate nick-end labeling assay.
Neurite outgrowth was severely restricted following thapsigargin injury. Outgrowth was potentiated, however, by the addition of concentrations of 1 and 10 μM cyclosporin A in a dose-dependent fashion. Similarly, addition of 10 nM FK506 increased the percentage of neurites in the 20- to 40-micron range. A low dose (1 μM) of dexamethasone did not have a significant effect on neurite outgrowth, but a higher dose (10 μM) increased the percentage of neurites in the 10- to 45-micron range. These agents also lessened the degree of thapsigargin-induced apoptosis.

Conclusions
Immunosuppressive agents such as cyclosporin A, FK506, and dexamethasone can potentiate neurite outgrowth and protect against apoptotic cell death in a human postmitotic neuronal cell line. Such effects may have implications for lessening neuronal injury after neurotrauma, stroke, or neurodegeneration.