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Sarikonda A, Sami A, Hines K, Self DM, Isch E, Leibold A, Keppetipola KM, Gonzalez G, Mansoor Ali D, Thalheimer S, Heller J, Prasad S, Jallo J, Sharan A, Vaccaro AR, Harrop J, Sivaganesan A. What Is the Value Proposition of Evidence-Based Guidelines? An Application of the Operative Value Index for Lumbar Fusions. World Neurosurg 2024; 189:e832-e840. [PMID: 38977127 DOI: 10.1016/j.wneu.2024.07.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2024] [Revised: 06/30/2024] [Accepted: 07/01/2024] [Indexed: 07/10/2024]
Abstract
BACKGROUND Elective lumbar fusions have received criticism for inappropriate utilization. Here, we use a novel Operative Value Index (OVI) to assess whether "indicated," evidence-based lumbar fusions are associated with increased value (outcomes per dollar spent). METHODS This study is a retrospective analysis of a prospective observational cohort of 294 patients undergoing elective lumbar fusions at a single large academic institution. All patients were preoperatively evaluated by a panel of neurosurgeons for concordance with evidence-based medicine (EBM), determined through guidelines from the North American Spine Society. Oswestry Disability Index (ODI) scores were collected for all patients both preoperatively and at 6-months postoperatively. Time-driven activity-based costing was employed to determine both direct and indirect intraoperative costs. The OVI was defined as the percent improvement in ODI per $1000 spent intraoperatively. Generalized linear mixed model regression, adjusting for confounders, was performed to assess whether EBM-concordant surgeries were associated with higher OVI. RESULTS Of 294 elective lumbar fusions, 92.9% (n = 273) were EBM-concordant. The average total cost of an EBM-concordant lumbar fusion was $17,932 (supplies: $13,020; personnel: $4314), compared to $20,616 (supplies: $15,467; personnel: $4758) for an EBM-discordant fusion. Average OVI was 2.27 for a concordant fusion, compared to 0.11 for a discordant fusion. Generalized linear mixed model analysis revealed that EBM-concordant cases were associated with significantly higher OVI (β-coefficient 2.0, P < 0.001). CONCLUSIONS EBM-concordant fusions were associated with 2% greater improvement in ODI scores from baseline for every $1000 spent intraoperatively. Systematic methods for increasing guideline adherence for lumbar fusions could therefore improve value at scale.
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Affiliation(s)
- Advith Sarikonda
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA.
| | - Ashmal Sami
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - Kevin Hines
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - D Mitchell Self
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - Emily Isch
- Department of General Surgery, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Adam Leibold
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - Kavantissa M Keppetipola
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - Glenn Gonzalez
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - Daniyal Mansoor Ali
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - Sara Thalheimer
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - Joshua Heller
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - Srinivas Prasad
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - Jack Jallo
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - Ashwini Sharan
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - Alexander R Vaccaro
- Department of Orthopaedic Surgery, Rothman Orthopedic Institute, Philadelphia, Pennsylvania, USA
| | - James Harrop
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - Ahilan Sivaganesan
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
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Sivaganesan A, Sarikonda A, Leibold A, Harrop J, Vaccaro AR, James BC. The Wasteful Neurosurgeon? World Neurosurg 2024; 187:285-286. [PMID: 38749823 DOI: 10.1016/j.wneu.2024.04.105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/07/2024]
Affiliation(s)
- Ahilan Sivaganesan
- Department of Neurological Surgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - Advith Sarikonda
- Department of Neurological Surgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA; Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Adam Leibold
- Department of Neurological Surgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - James Harrop
- Department of Neurological Surgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - Alexander R Vaccaro
- Department of Orthopedic Surgery, Rothman Orthopedic Institute, Philadelphia, Pennsylvania, USA
| | - Brent C James
- Department of Internal Medicine, Clinical Excellence Research Center (CERC), Stanford University School of Medicine, Stanford, California, USA
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Gonzalez GA, Porto G, Hines K, Franco D, Montenegro TS, Mahtabfar A, O’Leary M, Miao J, Thalheimer S, Heller JE, Sharan A, Harrop J. Clinical Outcomes with and without Adherence to Evidence-Based Medicine Guidelines for Lumbar Degenerative Spondylolisthesis Fusion Patients. J Clin Med 2023; 12:jcm12031200. [PMID: 36769851 PMCID: PMC9917667 DOI: 10.3390/jcm12031200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Accepted: 01/31/2023] [Indexed: 02/05/2023] Open
Abstract
INTRODUCTION Degenerative lumbar spondylolisthesis (DS) patients are treated with instrumented fusion, following EBM guidelines, and typically have excellent clinical outcomes. However, not all lumbar fusion procedures adhere to EBM guidelines, typically due to a lack of prospective data. OBJECTIVE This retrospective study compared outcomes of DS lumbar fusion patients treated according to EBM guidelines (EBM concordant) to lumbar fused patients with procedures that did not have clear EBM literature that supported this treatment, the goal being to examine the value of present EBM to guide clinical care. METHODS A total of 125 DS patients were considered EBM concordant, while 21 patients were EBM discordant. Pre- and postsurgical ODI scores were collected. Clinical outcomes were stratified into substantial clinical benefit (SCB ΔODI >10 points), minimal clinical importance benefit (MCID ΔODI ≥ 5 points), no MCID (ΔODI < 5 points), and a group that showed no change or worsening ODI. Fisher's exact and χ2 tests for categorical variables, Student's t-test for continuous variables, and descriptive statistics were used. Statistical tests were computed at the 95% level of confidence. RESULTS Analysis of 125 degenerative spondylolisthesis patients was performed comparing preoperative and postoperative (6 months) ODI scores. ODI improved by 8 points in the EBM concordant group vs. 2.1 points in the EBM discordant group (p = 0.002). Compliance with EBM guidelines was associated with an odds ratio (OR) of 2.93 for achieving MCID ([CI]: 1.12-7.58, p = 0.027). CONCLUSIONS Patients whose lumbar fusions met EBM criteria had better self-reported outcomes at six months than those who did not meet the requirements. A greater knowledge set is needed to help further support EBM-guided patient care.
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Affiliation(s)
- Glenn A. Gonzalez
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, PA 19107, USA
- Correspondence:
| | - Guilherme Porto
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, PA 19107, USA
| | - Kevin Hines
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, PA 19107, USA
| | - Daniel Franco
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, PA 19107, USA
| | - Thiago S. Montenegro
- Department of Neurosurgery, Spectrum Health/Michigan State University, Grand Rapids, MI 49503, USA
| | - Aria Mahtabfar
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, PA 19107, USA
| | - Matthew O’Leary
- Department of Medicine, Drexel University College of Medicine, Philadelphia, PA 19104, USA
| | - Jingya Miao
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, PA 19107, USA
| | - Sara Thalheimer
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, PA 19107, USA
| | - Joshua E. Heller
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, PA 19107, USA
| | - Ashwini Sharan
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, PA 19107, USA
| | - James Harrop
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, PA 19107, USA
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Adl Amini D, Moser M, Oezel L, Zhu J, Shue J, Sama AA, Cammisa FP, Girardi FP, Hughes AP. Development of a decision-making pathway for utilizing standalone lateral lumbar interbody fusion. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2021; 31:1611-1620. [PMID: 34713353 DOI: 10.1007/s00586-021-07027-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 09/17/2021] [Accepted: 10/11/2021] [Indexed: 12/11/2022]
Abstract
PURPOSE To develop a decision-making pathway for primary SA-LLIF. Furthermore, we analyzed the agreement of this pathway and compared outcomes of patients undergoing either SA-LLIF or 360-LLIF. METHOD A decision-making pathway for SA-LLIF was created based on the results of interviews/surveys of senior spine surgeons with over 10 years of experience. Internal validity was retrospectively evaluated using consecutive patients undergoing either SA-LLIF or 360-LLIF between 01/2018 and 07/2020 with 3D-printed Titanium cages. An outcome assessment looking primarily at revision surgery and secondary at cage subsidence, changes in disk and foraminal height, global and segmental lumbar lordosis, duration of surgery, estimated blood loss, and length of stay was carried out. RESULTS 78 patients with 124 treated levels (37 SA-LLIF, 41 360-LLIF) were retrospectively analyzed. The pathway showed a direct agreement (SA-LLIF) of 100.0% and an indirect agreement (360-LLIF) of 95.1%. Clinical follow-up averaged 13.5 ± 6.5 months including 4 revision surgeries in the 360-LLIF group and none in the SA-LLIF group (p = 0.117). Radiographic follow-up averaged 9.5 ± 4.3 months, with no statistically significant difference in cage subsidence rate between the groups (p = 0.440). Compared to preoperative images, patients in both groups showed statistically significant changes in disk height (p < 0.001), foraminal height (p < 0.001), as well as restoration of segmental lordosis (p < 0.001 and p = 0.018). The SA-LLIF group showed shorter duration of surgery, less estimated blood loss and shorter LOS (p < 0.001). CONCLUSION The proposed decision-making pathway provides a guide to adequately select patients for SA-LLIF. Further studies are needed to assess the external applicability and validity. LEVEL OF EVIDENCE III Diagnostic: individual cross-sectional studies with consistently applied reference standard and blinding.
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Affiliation(s)
- Dominik Adl Amini
- Hospital for Special Surgery, Spine Care Institute, 535 East 70th Street, New York, NY, 10021, USA.,Department of Orthopedic Surgery and Traumatology, Charité University Hospital Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Manuel Moser
- Hospital for Special Surgery, Spine Care Institute, 535 East 70th Street, New York, NY, 10021, USA
| | - Lisa Oezel
- Hospital for Special Surgery, Spine Care Institute, 535 East 70th Street, New York, NY, 10021, USA.,Department of Orthopedic Surgery and Traumatology, University Hospital Duesseldorf, Moorenstr. 5, 40225, Duesseldorf, Germany
| | - Jiaqi Zhu
- Hospital for Special Surgery, Spine Care Institute, 535 East 70th Street, New York, NY, 10021, USA
| | - Jennifer Shue
- Hospital for Special Surgery, Spine Care Institute, 535 East 70th Street, New York, NY, 10021, USA
| | - Andrew A Sama
- Hospital for Special Surgery, Spine Care Institute, 535 East 70th Street, New York, NY, 10021, USA
| | - Frank P Cammisa
- Hospital for Special Surgery, Spine Care Institute, 535 East 70th Street, New York, NY, 10021, USA
| | - Federico P Girardi
- Hospital for Special Surgery, Spine Care Institute, 535 East 70th Street, New York, NY, 10021, USA
| | - Alexander P Hughes
- Hospital for Special Surgery, Spine Care Institute, 535 East 70th Street, New York, NY, 10021, USA.
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Al Saiegh F, Philipp L, Hughes LP, Montenegro TS, Hines K, Gonzalez GA, Mahtabfar A, Andrews C, Keppetipola K, Franco D, Hafazalla K, Khanna O, Mouchtouris N, Self DM, Heller J, Prasad S, Jallo J, Sharan AD, Harrop JS. The Impact of Incorporating Evidence-Based Guidelines for Lumbar Fusion Surgery in Neurosurgical Resident Education. World Neurosurg 2021; 154:e382-e388. [PMID: 34293523 DOI: 10.1016/j.wneu.2021.07.045] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 07/09/2021] [Indexed: 10/20/2022]
Abstract
BACKGROUND Instrumented fusion procedures are essential in the treatment of degenerative lumbar spine disease to alleviate pain and improve neurological function, but they are being performed with increasing incidence and variability. We implemented a training module for neurosurgery residents that is based on evidence-based criteria for lumbar fusion surgery and measured its effectiveness in residents' decision making regarding whether patients should or should not undergo instrumented fusion. METHODS The study design was a pretest versus posttest experiment conducted from September 2019 until July 2020 to measure improvement after formalized instruction on evidence-based guidelines. Neurosurgery residents of all training levels at our institution participated. A test was administered at the beginning of each academic year. The highest possible score was 18 points in each pretest and posttest. RESULTS There was a general trend of test score improvement across all levels of training with a greater degree of change for participants with lower compared with higher pretest scores, indicating a possible ceiling effect. Paired t test demonstrated an overall mean score increase of 2 points (P < 0.0001), equivalent to an 11.11% increase (P < 0.0001). Stratified by training group, mean absolute change in test score was 2 (P = 0.0217), 1.67 (P = 0.0108), and 2.25 (P = 0.0173) points for junior, midlevel, and senior training groups, respectively. CONCLUSIONS Incorporating a targeted evidence-based learning module for lumbar spine fusion surgery can improve neurosurgery residents' clinical decision making toward a more uniform practice supported by published data.
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Affiliation(s)
- Fadi Al Saiegh
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA.
| | - Lucas Philipp
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - Liam P Hughes
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - Thiago Scharth Montenegro
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - Kevin Hines
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - Glenn A Gonzalez
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - Aria Mahtabfar
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - Carrie Andrews
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - Kavantissa Keppetipola
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - Daniel Franco
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - Karim Hafazalla
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - Omaditya Khanna
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - Nikolaos Mouchtouris
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - Dwight Mitchell Self
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - Joshua Heller
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - Srinivas Prasad
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - Jack Jallo
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - Ashwini D Sharan
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
| | - James S Harrop
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA
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Montenegro TS, Elia C, Hines K, Buser Z, Wilson J, Ghogawala Z, Kurpad SN, Sciubba DM, Harrop JS. Are Lumbar Fusion Guidelines Followed? A Survey of North American Spine Surgeons. Neurospine 2021; 18:389-396. [PMID: 34218620 PMCID: PMC8255757 DOI: 10.14245/ns.2142136.068] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 03/05/2021] [Accepted: 03/16/2021] [Indexed: 12/22/2022] Open
Abstract
OBJECTIVE To evaluate the use of guidelines for lumbar spine fusions among spine surgeons in North America. METHODS An anonymous survey was electronically sent to all AO Spine North America members. Survey respondents were asked to indicate their opinion surrounding the suitability of instrumented fusion in a variety of clinical scenarios. Fusion indications in accordance with North America Spine Society (NASS) guidelines for lumbar fusion were considered NASS-concordant answers. Respondents were considered to have a NASS-concordant approach if ≥ 70% (13 of 18) of their answers were NASS-concordant answers. Comparisons were performed using bivariable statistics. RESULTS A total of 105 responses were entered with complete data available on 70. Sixty percent of the respondents (n = 42) were considered compliant with NASS guidelines. NASS-discordant responses did not differ between surgeons who stated that they include the NASS guidelines in their decision-making algorithm (5.10 ± 1.96) and those that did not (4.68 ± 2.09) (p = 0.395). The greatest number of NASS-discordant answers in the United States. was in the South (5.75 ± 2.09), with the lowest number in the Northeast (3.84 ± 1.70) (p < 0.01). For 5 survey items, rates of NASS-discordant answers were ≥ 40%, with the greatest number of NASS-discordant responses observed in relation to indications for fusion in spinal deformity (80%). Spine surgeons utilizing a NASS-concordant approach had a significant lower number of NASS-discordant answers for synovial cysts (p = 0.03), axial low back pain (p < 0.01), adjacent level disease (p < 0.01), recurrent stenosis (p < 0.01), recurrent disc herniation (p = 0.01), and foraminal stenosis (p < 0.01). CONCLUSION This study serves an important role in clarifying the rates of uptake of clinical practice guidelines in spine surgery as well as to identify barriers to their implementation.
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Affiliation(s)
- Thiago S. Montenegro
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, PA, USA
| | - Christopher Elia
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, PA, USA
| | - Kevin Hines
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, PA, USA
| | - Zorica Buser
- Department of Orthopaedic Surgery, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Jefferson Wilson
- Division of Neurosurgery, Department of Surgery, University of Toronto, Toronto, ON, Canada
| | - Zoher Ghogawala
- Department of Neurosurgery, Lahey Hospital and Medical Center, Burlington, MA, USA
| | - Shekar N. Kurpad
- Department of Neurological Surgery, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Daniel M. Sciubba
- Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - James S. Harrop
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, PA, USA
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