bluuebunny/crossref_metadata_2025_split huggingface dataset:
Primary Care Residents in Teaching Health Centers: Their Intentions to Practice in Underserved Settings After Residency Training
Authors: Talib Zohray , Jewers Mariellen Malloy , Strasser Julia H. , Popiel David K. , Goldberg Debora Goetz , Chen Candice , Kepley Hayden , Mullan Fitzhugh , Regenstein Marsha 
Published: August 2017

Purpose
To describe the residents who chose to train in teaching health centers (THCs), which are community-based ambulatory patient care sites that sponsor primary care residencies, and their intentions to practice in underserved settings.

Method
The authors surveyed all THC residents training in academic years 2013–2014, 2014–2015, and 2015–2016, comparing their demographic characteristics with data for residents nationally, and examined THC residents’ intentions to practice in underserved settings using logistic regression analysis.

Results
The overall survey response rate was 89% (1,031/1,153). THC resident respondents were similar to residents nationally in family medicine, geriatrics, internal medicine, obstetrics–gynecology, pediatrics, and psychiatry in terms of gender, age, race, and ethnicity. Twenty-nine percent (283) of respondents came from a rural background, and 46% (454) had an educationally and/or economically disadvantaged background. More than half (524; 55%) intended to practice in an underserved setting on completion of their training. Respondents were more likely to intend to practice in an underserved area if they came from a rural background (odds ratio 1.58; 95% confidence interval 1.08, 2.32) or disadvantaged background (odds ratio 2.81; 95% confidence interval 1.91, 4.13).

Conclusions
THCs attract residents from rural and/or disadvantaged backgrounds who seem to be more inclined to practice in underserved areas than those from urban and economically advantaged roots. THC residents’ intentions to practice in underserved areas indicate that primary care training programs sponsored by community-based ambulatory patient care sites represent a promising strategy to improve the U.S. health care workforce distribution.
Atlas Fractures and Atlas Osteosynthesis: A Comprehensive Narrative Review
Authors: Kandziora Frank , Chapman Jens R. , Vaccaro Alexander R. , Schroeder Gregory D. , Scholz Matti 
Published: August 2017

Summary:
Most atlas fractures are the result of compression forces. They are often combined with fractures of the axis and especially with the odontoid process. Multiple classification systems for atlas fractures have been described. For an adequate diagnosis, a computed tomography is mandatory. To distinguish between stable and unstable atlas injury, it is necessary to evaluate the integrity of the transverse atlantal ligament (TAL) by magnetic resonance imaging and to classify the TAL lesion. Studies comparing conservative and operative management of unstable atlas fractures are unfortunately not available in the literature; neither are studies comparing different operative treatment strategies. Hence all treatment recommendations are based on low level evidence. Most of atlas fractures are stable and will be successfully managed by immobilization in a soft/hard collar. Unstable atlas fractures may be treated conservatively by halo-fixation, but nowadays more and more surgeons prefer surgery because of the potential discomfort and complications of halo-traction. Atlas fractures with a midsubstance ligamentous disruption of TAL or severe bony ligamentous avulsion can be treated by a C1/2 fusion. Unstable atlas fractures with moderate bony ligamentous avulsion may be treated by atlas osteosynthesis. Although the evidence for the different treatment strategies of atlas fractures is low, atlas osteosynthesis has the potential to change treatment philosophies. The reasons for this are described in this review.
The Need of Validated Disease-Specific Outcome Instruments for Spine Trauma
Authors: Oner Cumhur , Sadiqi Said , Lehr Anne Mechteld , Schroeder Gregory D. , Vaccaro Alexander R. 
Published: August 2017

Summary:
This article focuses on patient-reported and clinician-reported outcome measures in spine trauma care. The measurement of the quality of care and functional and health-related quality of life outcomes of spine trauma patients has become increasingly important. However, no outcome instrument is specifically designed, validated, or universally adapted for this specific patient population. Issues specific to spinal trauma patients may not be adequately addressed by the instruments that are currently used in the literature and the daily clinical practice. The AOSpine Knowledge Forum Trauma initiated a project to develop and validate such instruments for spine trauma patients. To reflect the different perspectives of patients and the treating surgeons, 2 separate tools are being developed: the Patient Reported Outcome Spine Trauma (AOSpine PROST) and Clinician Reported Outcome Spine Trauma (AOSpine CROST). These tools hold promise, as useful instruments to measure the outcomes of spine trauma patients with and without neurological deficit, making it more feasible for clinical use as well. Treating surgeons around the world are encouraged to use the AOSpine PROST and AOSpine CROST in daily clinical practice and for research purposes to create and contribute to evidence-based and patient-centered care. Using the same outcome measures that are specifically developed and validated for traumatic spine injuries will allow us to compare the outcomes of various treatments in a valid and reproducible fashion. This contributes to a reduction of the ongoing controversies and providing the best treatments for our patients.
AOSpine Classification Systems (Subaxial, Thoracolumbar)
Authors: Schnake Klaus J. , Schroeder Gregory D. , Vaccaro Alexander R. , Oner Cumhur 
Published: August 2017

Summary:
Numerous classification systems for subaxial and thoracolumbar spine injuries were proposed in the past with the attempt to facilitate communication between physicians. The AO-Magerl, thoracolumbar system, and Subaxial Cervical Spine Injury Classification systems are all well known, but did not achieve universal international adoption. A group of international experienced spine trauma surgeons were brought together by AOSpine with the goal to develop a comprehensive yet simple classification system for spinal trauma. This article is a synopsis of the proposed subaxial and thoracolumbar classification systems. In several studies, this classification system was developed using an iterative consensus process among the clinical experts in sufficient number and quality of DICOM images of real cases searching for meaningful and reproducible patterns. Both systems are based on 3 injury morphology types: compression injuries (A), tension band injuries (B), and translational injuries (C) with a total of 9 subgroups. In the subaxial cervical spine 4 additional subtypes for facet injuries exist. Patient-specific modifiers and neurologic status were also included to aid surgeons in therapeutic decision making. The proposed classification systems for subaxial and thoracolumbar injuries showed substantial intraobserver and interobserver reliability (κ = 0.64–0.85) for grading fracture type. Grading for the subtypes varied considerably due to the low frequency of certain injury subtypes among other reasons. In summary, the AOSpine thoracolumbar and subaxial cervical spine injury systems show substantial reliability, thus being valuable tools for clinical and research purposes.
Do Formal Laminectomy and Timing of Decompression for Patients With Sacral Fracture and Neurologic Deficit Affect Outcome?
Authors: Kepler Christopher K. , Schroeder Gregory D. , Hollern Douglas A. , Chapman Jens R. , Fehlings Michael G. , Dvorak Marcel , Bellabarba Carlo , Vaccaro Alexander R. 
Published: August 2017

Objectives:
To identify whether formal sacral decompression provides improvement in outcome for patients with neurologic deficit after sacral fracture compared with patients treated with indirect decompression and whether the timing of surgical decompression influences neurologic outcome?

Data Sources:
MEDLINE was searched via PubMed using combinations of the following search terms: “Sacral fracture,” “Traumatic Sacral fracture,” “Sacral fracture decompression,” “Sacral fracture time to decompression,” “Sacral Decompression.” Only clinical studies on human subjects and in the English language were included.

Study Selection:
Studies that did not provide sufficient detail to confirm the nature of the sacral injury, treatment rendered, and neurologic outcome were excluded. Studies using subjects less than 18 years of age, cadavers, nonhuman subjects, or laboratory simulations were excluded. All other relevant studies were reviewed in detail.

Data Extraction:
All studies were assigned a level of evidence using the grading tool described by the Centre for Evidence-Based Medicine and all studies were analyzed for bias. Both cohorts in articles comparing 2 groups of patients treated differently were included in the appropriate group. Early decompression was defined as before 72 hours.

Data Synthesis:
The effect of decompression technique and timing of decompression surgery on partial and complete neurologic recovery was estimated using a generalized linear mixed model to implement a logistic regression with a study-level random effect.

Conclusions:
There was no benefit to early decompression within 72 hours and no difference between formal laminectomy and indirect decompression with respect to neurologic recovery.
Fractures in Spinal Ankylosing Disorders: A Narrative Review of Disease and Injury Types, Treatment Techniques, and Outcomes
Authors: Rustagi Tarush , Drazin Doniel , Oner Cumhur , York Jonathan , Schroeder Gregory D. , Vaccaro Alexander R. , Oskouian Rod J. , Chapman Jens R. 
Published: August 2017

Introduction:
Spinal ankylosing disorders encompass ankylosing spondylitis (AS), disseminated hyperostosis of the spine, and end-stage spondylosis. All these result in a stiffened and frequently deformed spinal column. This makes the spinal column highly susceptible to severe injuries that are commonly associated with unfavorable outcomes. Improved understanding of the underlying disease processes and clinical comorbidities may alter the poor injury related morbidity and mortality outcomes.

Methods:
A systematic review of the MEDLINE and PubMed databases was performed using the following key words to identify articles published between 2001 and 2016: “ankylosing spondylitis,” “epidemiology,” “DISH,” “treatment,” “outcome,” and/or “fracture.” Articles were read for data on methodology (retrospective vs. prospective), type of treatment, number of patients, mean patient age, and mean follow-up.

Results:
Twenty-one identified articles were analyzed. Average age was 63.4 years. Most patients were men. Ground level fall or low energy trauma caused most injuries. Diagnosis was delayed in 15%–41% cases. Hyperextension fracture patterns were most common. Cervical spine fractures were more common than thoracolumbar fractures, with the highest prevalence between C5 and C7. Neurologic deficits were encountered in 21%–100% of patients. Operative fixation and fusion were performed in 40%–100% of patients. Mortality was reported between 0% and 32% at 1 year postinjury. Complications were encountered in 84% of patients, mostly in the form of pneumonia, respiratory failure, and pseudoarthrosis. Neurologic deterioration has been reported in 16% of patients. Fusion was successful in 87%–100% of patients. Neurologic deficits improved in function in 6%–66% at the final follow-up.

Conclusions:
Because of the stiffening of the spinal column, patients with spinal ankylosing disorders are preferably evaluated for spinal fractures and ligamentous injuries after even trivial trauma. Spinal injuries in patients with AS are difficult to diagnose on plain radiographs; computed tomography and magnetic resonance imaging are recommended instead. The entire spine should be scanned for multilevel involvement. Although osteoporosis makes fixation of spine implants a significant concern, the literature has reported that most patients with AS treated surgically had good outcomes. Numerous studies have reported risks associated with conservative management.
Biomechanical Analysis of the Proximal Femoral Locking Compression Plate: Do Quality of Reduction and Screw Orientation Influence Construct Stability?
Authors: Zderic Ivan , Oh Jong-Keon , Stoffel Karl , Sommer Christoph , Helfen Tobias , Camino Gaston , Richards Geoff , Nork Sean E. , Gueorguiev Boyko 
Published: August 2017

Objectives:
To investigate biomechanically in a human cadaveric model the failure modes of the proximal femoral locking compression plate and explore the underlying mechanism.

Methods:
Twenty-four fresh-frozen paired human cadaveric femora with simulated unstable intertrochanteric fractures (AO/OTA 31-A3.3) were assigned to 4 groups with 6 specimens each for plating with proximal femoral locking compression plate. The groups differed in the quality of fracture reduction and plating fashion of the first and second proximal screws as follows: (1) anatomic reduction with on-axis screw placement; (2) anatomic reduction with off-axis screw placement; (3) malreduction with on-axis screw placement; (4) malreduction with off-axis screw placement. The specimens were tested until failure using a protocol with combined axial and torsional loading. Mechanical failure was defined as abrupt change in machine load–displacement data. Clinical failure was defined as 5 degrees varus tilting of the femoral head as captured with optical motion tracking.

Results:
Initial axial stiffness (in N/mm) in groups 1 to 4 was 213.6 ± 65.0, 209.5 ± 134.0, 128.3 ± 16.6, and 106.3 ± 47.4, respectively. Numbers of cycles to clinical and mechanical failure were 16,642 ± 10,468 and 8695 ± 1462 in group 1, 14,076 ± 3032 and 7449 ± 5663 in group 2, 8800 ± 8584 and 4497 ± 2336 in group 3, and 9709 ± 3894 and 5279 ± 4119 in group 4. Significantly higher stiffness and numbers of cycles to both clinical and mechanical failure were detected in group 1 in comparison with group 3, P ≤ 0.044.

Conclusions:
Generally, malreduction led to significantly earlier construct failure. The observed failures were cut-out of the proximal screws in the femoral head, followed by either screw bending, screw loosening, or screw fracture. Proper placement of the proximal screws in anatomically reduced fractures led to significantly higher construct stability. Our data also indicate that once the screws are placed off-axis (>5 degrees), the benefit of an anatomic reduction is lost.
Initial Cast Correction as a Predictor of Treatment Outcome Success for Infantile Idiopathic Scoliosis
Authors: Gomez Jaime A. , Grzywna Alexandra , Miller Patricia E. , Karlin Lawrence I. , Garg Sumeet , Sanders James O. , Sturm Peter F. , Sponseller Paul D. , D’Astous Jacques L. , Glotzbecker Michael P. 
Published: August 2017

Background:
Cast treatment for infantile idiopathic scoliosis patients ultimately corrects deformity in varying amounts. As the reasons for these differential outcomes are not fully elucidated, the aim of this study was to identify clinical and radiographic variables correlated with better cast correction.

Methods:
Patients in the Children’s Spine Study Group and Growing Spine Study Group registries who underwent cast treatment for idiopathic scoliosis between 2005 and 2013 with 1-year minimum follow-up were included. Data including major curve and rib-vertebra angle difference before cast, initial in-cast application, after cast treatment, and at most recent follow-up were collected. Univariable and multivariable regression analyses were used to identify factors associated with lower major curves at most recent follow-up.

Results:
A total of 68 patients were identified and followed for a mean of 2.5 (range, 1.1 to 5.4) years after cast treatment. Cast treatment lasted an average of 16.7 months, with a median of 6 cast applications (range, 2 to 19). Twenty-five subjects (37%) had a most recent major curve <15 degrees (success), whereas 43 had a curve that was >15 degrees (unresolved). Multivariable linear regression determined that younger age (P=0.02), smaller precast major curve (P<0.001), and greater percent major curve correction in initial cast (P=0.006) were associated with smaller major curve at most recent follow-up. Multivariable logistic regression determined that success patients were younger than unresolved patients (average age, 1.4 vs. 2.1 y; P=0.003), and had smaller in-cast major curves after initial cast application (average, 18 vs. 27 degrees; P=0.002).

Conclusions:
Infantile idiopathic scoliosis patients casted at an earlier age, with smaller major curves, and greater percent major curve correction in initial cast have the best prognosis. Patients’ percent major curve correction, which may represent curve flexibility and/or cast quality, is a predictor of treatment success when age and precast major curve are also taken into account.

Level of Evidence:
Level III—retrospective study.
Motion Necessary to Achieve Mallet Internal Rotation Positions in Children With Brachial Plexus Birth Palsy
Authors: Russo Stephanie A. , Kozin Scott H. , Zlotolow Dan A. , Nicholson Kristen F. , Richards James G. 
Published: August 2017

Background:
Upper extremity function in children with brachial plexus birth palsy (BPBP) is assessed with clinical tests such as the Mallet classification, which uses a hand to spine position to assess shoulder internal rotation, or the modified Mallet classification, which adds an additional internal rotation task (hand to belly). Children with BPBP frequently have difficulty performing the hand to spine task. This study compared scapulothoracic and glenohumeral (GH) parameters associated with successful completion of the hand to spine and hand to belly modified Mallet positions.

Methods:
Motion capture measurement of 32 children with BPBP was performed in hand on spine, internal rotation (hand to belly), hand to mouth, and maximal humerothoracic extension positions. Modified Mallet scores were determined by a hand surgeon.

Results:
Children with better hand to spine performance demonstrated significantly greater GH extension and a nonsignificant trend toward increased GH internal rotation compared with children with scores <3. Children with better internal rotation position performance demonstrated significantly greater GH internal rotation and no significant difference in GH extension. Hand on spine and internal rotation Mallet scores moderately correlated (Pearson r=0.469); however, 54% of children who could place their palms flat on their bellies could not reach behind their backs.

Conclusions:
Successfully reaching behind one’s back requires both internal rotation and extension, representing a multiplanar motion. The hand to belly performance is less affected by extension and should be considered for internal rotation assessment, particularly for children undergoing surgical intervention that may affect internal rotation.

Level of Evidence:
Level II.
Incidence and Fusion of Os Trigonum in a Healthy Pediatric Population
Authors: Knapik Derrick M. , Guraya Sahejmeet S. , Jones Jessica A. , Cooperman Daniel R. , Liu Raymond W. 
Published: August 2017

Background:
Accessory ossicles off the talus (os trigonum) are a common radiographic finding seen within the foot with variable symptomatology in adult and pediatric patients. Although most studies have examined the incidence of these anatomic variants in a retrospective manner, few have longitudinally followed the behavior of os trigonum over time. The aim of this study was to investigate the incidence, mean age of appearance and fusion, and fusion rate of os trigonum in a large cohort of asymptomatic pediatric patients.

Methods:
A total of 2620 serial digitized unilateral foot and ankle radiographs from 261 healthy white children (age range, 0.25 to 7 y at enrollment) were retrospectively reviewed. Radiographs were examined to determine the incidence of os trigonum, noting age of appearance and if present, the age of fusion. Skeletal maturity was graded based on ossification pattern of the calcaneal apophysis.

Results:
Radiographic evidence of os trigonum was present in 18% of patients (n=16 females, n=15 males) with radiographs extending 1 SD beyond the average age of os trigonum appearance. There was no difference in incidence between females and males (P=0.27), and os trigonum was found to appear at a significantly younger age in females (9.1±1.8 y) than males (10.4±2.0 y, P=0.04). Overall, 70% (n=26) of subjects with os trigonum achieved fusion by age 17 (mean, 9.5±1.6 y in females, 11.2±1.6 in males) with no significant difference between sexes (P=0.61). Grading of skeletal maturity at the time of fusion showed that both male and female subjects underwent fusion on average between calcaneal stages 2 and 3 (P=0.5).

Conclusions:
This study confirms a relatively large prevalence of os trigonum in a random pediatric population, and clarifies both the average age of onset and high rate of fusion at a relatively narrow range of skeletal maturity.

Level of Evidence:
Prognostic level II—retrospective study.
Preoperative Opioid Use is a Predictor of Poor Return to Work in Workers’ Compensation Patients After Lumbar Diskectomy
Authors: O’Donnell Jeffrey A. , Anderson Joshua T. , Haas Arnold R. , Percy Rick , Woods Stephen T. , Ahn Uri M. , Ahn Nicholas U. 
Published: August 2017

Study Design.
A retrospective cohort.

Objective.
The aim of this study was to determine the impact of preoperative opioid use in workers’ compensation (WC) patients undergoing lumbar diskectomy (LD).

Summary of Background Data.
The prevalence of back pain among opioid users approached 60%. Long-term opioid dependence in spine surgery patients is roughly 20%. Despite pervasive use, there is no evidence to support long-term opioid analgesic use for back pain.

Methods.
Ten thousand five hundred ninety-two patients received compensation from the Ohio Bureau of Workers’ Compensation for a lumbar disc herniation between 2005 and 2012. Patients with spine comorbidities, smoking history, or multilevel surgery were excluded. Preoperatively, 566 patients had no opioid use, 126 had short-term opioid use (STO), 315 had moderate opioid use (MTO), and 279 had long-term opioid use (LTO). The primary outcome was whether subjects returned to work (RTW).

Results.
Seven hundred twelve (55.4%) patients met our RTW criteria. There was a significant difference in RTW rates among the no opioid (64.1%), MTO (52.7%), and LTO (36.9%) populations. Multivariate logistic regression analysis found several covariates to be independent negative predictors of RTW status: preoperative opioid use [P < 0.01; odds ratio (OR) = 0.54], time to surgery (P < 0.01; OR = 0.98 per month), legal representation (P < 0.01; OR = 0.57), and psychiatric comorbidity (P = 0.02; OR = 0.36). Patients in the LTO group had higher medical costs (P < 0.01), rates of psychiatric comorbidity (P < 0.01), incidence of failed back surgery syndrome (FBSS) (P < 0.01), and postoperative opioid use (P < 0.01) compared with the STO and no opioid groups.

Conclusion.
Preoperative opioid use was determined to be a negative predictor of RTW rates after LD in WC patients. In addition, long-term preoperative opioid use was associated with higher medical costs, psychiatric illness, FBSS, and postoperative opioid use. Even a short or moderate course of preoperative opioids was associated with worse outcomes compared with no use. For WC patients undergoing LD, judicious use of preoperative opioid analgesics may improve clinical outcomes and reduce the opioid burden.

Level of Evidence: 3