Results of the AANS membership survey of adult spinal deformity knowledge: impact of training, practice experience, and assessment of potential areas for improved education

Clinical article

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Object

Adult spinal deformity (ASD) surgery is increasing in the spinal neurosurgeon's practice.

Methods

A survey of neurosurgeon AANS membership assessed the deformity knowledge base and impact of current training, education, and practice experience to identify opportunities for improved education. Eleven questions developed and agreed upon by experienced spinal deformity surgeons tested ASD knowledge and were subgrouped into 5 categories: 1) radiology/spinopelvic alignment, 2) health-related quality of life, 3) surgical indications, 4) operative technique, and 5) clinical evaluation. Chi-square analysis was used to compare differences based on participant demographic characteristics (years of practice, spinal surgery fellowship training, percentage of practice comprising spinal surgery).

Results

Responses were received from 1456 neurosurgeons. Of these respondents, 57% had practiced less than 10 years, 20% had completed a spine fellowship, and 32% devoted more than 75% of their practice to spine. The overall correct answer percentage was 42%. Radiology/spinal pelvic alignment questions had the lowest percentage of correct answers (38%), while clinical evaluation and surgical indications questions had the highest percentage (44%). More than 10 years in practice, completion of a spine fellowship, and more than 75% spine practice were associated with greater overall percentage correct (p < 0.001). More than 10 years in practice was significantly associated with increased percentage of correct answers in 4 of 5 categories. Spine fellowship and more than 75% spine practice were significantly associated with increased percentage correct in all categories. Interestingly, the highest error was seen in risk for postoperative coronal imbalance, with a very low rate of correct responses (15%) and not significantly improved with fellowship (18%, p = 0.08).

Conclusions

The results of this survey suggest that ASD knowledge could be improved in neurosurgery. Knowledge may be augmented with neurosurgical experience, spinal surgery fellowships, and spinal specialization. Neurosurgical education should particularly focus on radiology/spinal pelvic alignment, especially pelvic obliquity and coronal imbalance and operative techniques for ASD.

Abbreviations used in this paper:AANS = American Association of Neurological Surgeons; ASD = adult spinal deformity; HRQOL = health-related quality of life; PPA = percent positive agreement; SANS = Self-Assessment in Neurological Surgery.

Abstract

Object

Adult spinal deformity (ASD) surgery is increasing in the spinal neurosurgeon's practice.

Methods

A survey of neurosurgeon AANS membership assessed the deformity knowledge base and impact of current training, education, and practice experience to identify opportunities for improved education. Eleven questions developed and agreed upon by experienced spinal deformity surgeons tested ASD knowledge and were subgrouped into 5 categories: 1) radiology/spinopelvic alignment, 2) health-related quality of life, 3) surgical indications, 4) operative technique, and 5) clinical evaluation. Chi-square analysis was used to compare differences based on participant demographic characteristics (years of practice, spinal surgery fellowship training, percentage of practice comprising spinal surgery).

Results

Responses were received from 1456 neurosurgeons. Of these respondents, 57% had practiced less than 10 years, 20% had completed a spine fellowship, and 32% devoted more than 75% of their practice to spine. The overall correct answer percentage was 42%. Radiology/spinal pelvic alignment questions had the lowest percentage of correct answers (38%), while clinical evaluation and surgical indications questions had the highest percentage (44%). More than 10 years in practice, completion of a spine fellowship, and more than 75% spine practice were associated with greater overall percentage correct (p < 0.001). More than 10 years in practice was significantly associated with increased percentage of correct answers in 4 of 5 categories. Spine fellowship and more than 75% spine practice were significantly associated with increased percentage correct in all categories. Interestingly, the highest error was seen in risk for postoperative coronal imbalance, with a very low rate of correct responses (15%) and not significantly improved with fellowship (18%, p = 0.08).

Conclusions

The results of this survey suggest that ASD knowledge could be improved in neurosurgery. Knowledge may be augmented with neurosurgical experience, spinal surgery fellowships, and spinal specialization. Neurosurgical education should particularly focus on radiology/spinal pelvic alignment, especially pelvic obliquity and coronal imbalance and operative techniques for ASD.

From the origins of the discipline, spinal surgery has been a part of the field of neurosurgery. Spinal surgery now comprises the majority of neurosurgical procedures.2 Spinal surgery fellowships are currently the most popular postgraduate training programs in neurosurgery.8 Consistently, there has been a steady increase in neurosurgery spine job offerings in both academic and private practices.5 Spine specialty job offerings are now the most prevalent of all the neurosurgery subspecialties.6 These statistics underscore the importance of maintaining a solid contemporary neurosurgical knowledge base in the practice of modern spinal surgery.

Adult spinal deformity (ASD) is now recognized as a significant cause of pain and disability. Deformity in the sagittal plane,17 spinopelvic alignment,15 understanding of appropriate deformity-specific work-up, including hip joint evaluation, comprehensive knowledge of normal lumbar anatomy and lordosis, and indications for pelvic fixation must be included in the spinal surgeon's knowledge base.10,13 Failure to do so can result in treatment failure and poor patient outcome.11

Current knowledge of these basic ASD principles in the neurosurgery community has not been previously evaluated. In a recent survey of neurosurgical residents in the United States, 86% of responders felt that residency training in spinal surgery had adequately trained them for independent practice; however, deformity surgery was not a component.9 Neurosurgeons perform well on the spine section of the Self-Assessment in Neurological Surgery (SANS) examination, but deformity questions are extremely rare on the current SANS spine module.16 The prevalence of ASD is estimated at over 65% in patients over age 60 years.14 Neurosurgeons are evaluating these patients in their practices, yet they may not have been well prepared to do so in residency or fellowship. As management of ASD becomes an increasingly substantial component of the neurosurgery spine surgeon's practice, it is important to identify knowledge gaps with the goal of adapting neurosurgical education, knowledge requirements and training.

Methods

Survey Methodology

A 14-item multiple-choice questionnaire was distributed in 2 iPod touch messages at the American Association of Neurological Surgeons (AANS) annual meeting and 4 email blasts to all neurosurgeon members of the AANS, including those currently in residency/fellowship training and those who had completed training (see Appendix). Results were tallied by an independent administrator to maintain responder anonymity. The first 3 questions were designed to describe the demographics of the responders with respect to neurosurgical experience, training, and specialization. The first question asked how many years had passed since the responder finished training. The possible responses were: a) still in training, b) less than 5 years, c) 5–10 years, d) 10–15 years, and e) more than 15 years. The second question asked the responder if he/she had completed a spinal surgery fellowship. The third question asked the responder to report the percentage of his/her practice that was focused on spinal surgery. The possible responses were: a) 100%, b) 75%–99%, c) 50%–74%, d) 25%–49%, and e) less than 25%. The remaining questions were knowledge-based questions designed to evaluate ASD management (Figs. 1 and 2).3

Fig. 1.
Fig. 1.

Representation of Question 6 and multiple-choice options. The CT scan demonstrates degenerative disc disease at L4–5 and L5–S1, while the 36-inch standing radiograph demonstrates a significantly elevated sagittal vertical axis (SVA), indicating the cause of the patient's low-back pain. The correct answer is in boldface. In this case, 3-column osteotomy is required to correct the sagittal imbalance. This question was categorized as radiology/spinopelvic alignment, HRQOL, surgical indications, and operative technique.

Fig. 2.
Fig. 2.

Representation of Question 10 and multiple-choice options. The correct answer is in boldface. Bess et al.3 showed, in a large multicenter retrospective analysis, that in older patients, such as the patient described in this question, surgical intervention is best predicted by preoperative disability. This question was categorized as HRQOL, surgical indications, and clinical evaluation.

Knowledge-Based Question Categorization

Five expert spinal deformity surgeons (C.P.A., C.I.S., J.S.S., T.R.K., and M.K.R.) were asked to categorize the knowledge-based questions into 5 categories: 1) radiology/spinopelvic alignment, 2) health-related quality of life (HRQOL), 3) surgical indications, 4) operative technique, and 5) clinical evaluation. Some questions were assigned to more than one category. Radiology/spinopelvic alignment was defined as evaluation of radiographic studies and assessment and understanding of normal and abnormal coronal and sagittal alignment and pelvic parameters. HRQOL was defined as determining a probable patient quality of life outcome based on diagnosis, preoperative condition, and procedure. Surgical indications were defined as diagnosis and determining the appropriate procedure. Operative technique questions were defined by determination of the proper operative procedure for a given deformity. Lastly, clinical evaluation was defined as evaluation based on clinical experience with the patient. Ultimately, 8 questions were assigned to the radiology/spinopelvic alignment category, 4 to HRQOL, 5 to surgical indications, 6 to surgical technique, and 5 to clinical evaluation. The survey was also administered to an additional 10 expert spinal deformity surgeons for validation purposes.

Statistical Analysis

For the purposes of analysis, certain demographic variables were dichotomized. Responses to Question 1 were dichotomized into “less than 10 years” or “10 years or more.” Likewise, responses to Question 3 were dichotomized into “less than 75%” or “75% or more.” Differences in rate of correct answers (percent correct) between groups were compared by chi-square test. Interrater reliability was assessed for knowledge-based questions using percent positive agreement (PPA). Responses to each knowledge-based multiple-choice question were converted to binary form—correct or incorrect. The PPA was estimated by the number of correct answers relative to the average number of correct answers across all expert spine surgeons in the validation subgroup. All analyses were carried out using PASW Statistics 18 (SPSS); p values < 0.05 were considered statistically significant.

Results

Responder Demographics

Surveys were sent to 5929 neurosurgeon AANS members and 1852 resident members; 1456 (19%) members responded to the survey (Table 1). The majority of responders had been in practice for 10 years or longer. Only 15% of responders were still in training. Most had not completed a spinal surgery fellowship. Responders who had been in practice for less than 10 years were not more likely to have completed a spinal surgery fellowship than those who had been in practice longer (p = 0.05; 22% vs 18%, respectively). Most had practices that were less than 75% focused on spinal surgery. However, only 13% dedicated less than 25% of their practice to spinal surgery. Only 5% had practices that were entirely focused on spinal surgery. Responders who had completed a spinal surgery fellowship were more likely to dedicate at least 75% of their practice to spinal surgery than those who had not completed a fellowship (p < 0.001; 49% vs 28%, respectively). To determine how the responder group compared with the overall target group, we analyzed the demographic characteristics of the AANS United States membership, provided to us by AANS membership services: 3921 (60%) have been in practice more than 10 years, and 293 AANS members (6%) have completed a spinal surgery fellowship. Data on the percentage of spinal surgery focus were not available, but 1835 members (36%) consider their primary focus to be spinal surgery.

TABLE 1:

Demographic characteristics of the 1456 AANS neurosurgeons who responded to the ASD surgery survey

DemographicNo. of Respondents%
experience
 <10 yrs62443
 ≥10 yrs83257
 total1456
 missing00
training
 spinal surgery fellowship28820
 no fellowship114780
 total1435
 missing211.4
specialization
 ≥75% spine45732
 <75% spine96568
 total1422
 missing342.3

Overall Survey Responses

The overall rate of correct responses was 42% (Table 2). Radiology/spinopelvic alignment questions had the lowest correct response rate, while clinical evaluation and surgical indications questions had the highest. We next evaluated the effect of responder experience, training, and specialization on correct response (Fig. 3). Being in practice for 10 years or more was associated with a small but statistically significant increase in overall percent correct compared with the rate for respondents who had been in practice less than 10 years (p < 0.001; 43% vs 41%). Completion of a spinal surgery fellowship was associated with a modest but statistically significant increase in the overall percent correct compared with the rate for those who had not completed a fellowship, yet the percentage was still less than 50% (p < 0.001; 47% vs 40%). Increased spinal surgery specialization was associated with the largest increase in percent correct compared with the rate for responders whose practices comprised less than 75% spine surgery (p < 0.001; 50% vs 37%).

TABLE 2:

Overall response to knowledge-based AANS ASD surgery survey questions by category

CategoryNo. of Responses% Correct
radiology/spinopelvic alignment
 correct336038
 incorrect542862
 total8788
 missing286025
HRQOL
 correct182842
 incorrect252558
 total4353
 missing147125
surgical indications
 correct242844
 incorrect304656
 total5474
 missing180625
operative technique
 correct250739
 incorrect397661
 total6483
 missing225326
clinical evaluation
 correct248144
 incorrect311556
 total5596
 missing168423
overall
 correct500042
 incorrect699458
 total11,994
 missing402225
Fig. 3.
Fig. 3.

Bar graph representation of percentage of correct answers for the overall survey comparing the different demographic groups of the responders. N = no; Y = yes.

Radiology/Spinopelvic Alignment

As noted above, radiology/spinopelvic alignment questions were associated with the lowest percentage of correct responses. There was no difference between those with less and those with more neurosurgical experience (p = 0.62; 39% vs 39%, respectively; Fig. 4A). Responders who had completed a spine fellowship had a significantly higher percentage of correct radiology/spinopelvic alignment responses than those who had not (p < 0.001; 44% vs 37%, respectively). The biggest difference in the rate of correct responses was seen when results were stratified by degree of specialization (Q3; 46% for ≥ 75% spinal surgery vs 35% for < 75% spinal surgery, p < 0.001).

Fig. 4.
Fig. 4.

Bar graphs depicting the differences among responder demographic groups for each of the question categories. The p values for significant differences are noted above the respective bars. Radiology/spinopelvic alignment questions are represented in A, HRQOL in B, surgical indications in C, operative technique in D, and clinical evaluation in E.

Health-Related Quality of Life

There was a small, but statistically significant, difference between those with less and those with more neurosurgical experience with respect to HRQOL questions (p = 0.04; 46% vs 42%, respectively; Fig. 4B). However, responders who had completed a spinal surgery fellowship (p = 0.001; 47% vs 41% for no fellowship) and those with more specialized practices (p < 0.001; 47% vs 39% for less-specialized practices) had significantly higher rates of correct responses.

Surgical Indications

For questions relating to surgical indications, increased experience was associated with a small but statistically significant increase in percent correct (p = 0.04; 47% vs 44% for < 10 years in practice; Fig. 4C). Spinal surgery fellowship was associated with a larger increase in percent correct (p < 0.001; 51% vs 43% for no spine fellowship), while more specialized practice was associated with the largest increase (p < 0.001; 55% vs 39% for < 75% spine practice).

Operative Technique

For operative technique questions, there was a small but significant trend toward lower percent correct for those who had been in practice for more than 10 years (p = 0.02; 38% vs 41% for less than 10 years of practice; Fig. 4D). Completion of a spine fellowship was highly significantly associated with increased percent correct (p < 0.001; 45% vs 37% for no fellowship). Again, increased specialization was associated with the largest increase in percent correct answers compared with those with practices < 75% spine focused (p < 0.001; 46% vs 35%, respectively).

Clinical Evaluation

Both increased neurosurgical experience (p < 0.001; 47% vs 40% for less than 10 years in practice) and fellowship training (p = 0.02; 48% vs 44% for no spine fellowship; Fig. 4E) were associated with similar increases in percent correct response. Increased specialization was associated with the largest increase in percent correct (p < 0.001; 54% vs 39% for < 75% spine practice).

Coronal Balance

Question 8 described a patient with thoracolumbar scoliosis, fractional lumbosacral curve, and pelvic obliquity who was at risk for postoperative coronal imbalance if only the thoracolumbar curve was fully corrected (Fig. 5 upper). This specific question was associated with a very low rate of correct responses (15%). Increased neurosurgical experience was associated with a small but significant decrease in percent correct (p < 0.001; < 10 years in practice 19% vs ≥ 10 years in practice 11%). However, neither completion of a fellowship (p = 0.08; completed a fellowship 18% vs no fellowship 14%) nor spinal surgery specialization (p = 0.38; ≥ 75% spine practice 13% vs < 75% spine practice 15%) was associated with an improved rate of correct responses (Fig. 5 lower).1

Fig. 5.
Fig. 5.

Representation of Question 8 and multiple-choice options (upper). The correct answer is in boldface. This question was categorized as radiology/spinopelvic alignment, HRQOL, operative technique, and clinical evaluation. This question was associated with a low percentage of correct answers and no statistically significant differences between any of the demographic categories, as shown in the graph (lower).

Survey Reliability

The overall interrater reliability for the knowledgebased portion of the survey demonstrated a PPA of 85.4% (Table 3). All but one of the expert spinal deformity surgeons answered at least 8 questions correctly; the remaining surgeon answered 7 answers correctly. The percentage of agreement for each question ranged from 50% to 100%. Survey Questions 11 and 12 demonstrated the least amount of agreement, 50% and 60%, respectively.

TABLE 3:

Interrater reliability—PPA among 10 expert spinal deformity surgeons*

Question No.PPA
490%
5100%
690%
7100%
890%
9100%
1090%
1150%
1260%
1390%
1480%

Test interrater reliability = 85.4%.

Discussion

The results of the AANS membership ASD surgery survey indicate a 42% overall percent correct rate. These data highlight an opportunity for improved education within the neurosurgical spinal specialty field in light of our aging population, the increasing percentage of spinal fusion performed by neurosurgeons, and the increasing prevalence of scoliosis. Training in the principles of ASD surgery is critical for all spine surgeons, even those not routinely performing long-segment fusions, as even shortsegment fusions can disrupt global spinal balance.11

Of the 3 demographic variables, increased neurosurgical experience was the least beneficial in terms of spinal deformity knowledge acquisition. The largest difference between increased experience and decreased experience was noted in the clinical evaluation category (an increase of 8 percentage points in the correct response rate for the group with increased experience). With that exception, there was no difference noted in two categories and only modest improvement in the remaining two. This is in contrast to degenerative spine surgery, where a recent report demonstrated significant improvement with spinal surgery experience with respect to operative technique.12 Our data indicate that, even with increased experience as an attending neurosurgeon, there is no appreciable improvement in deformity knowledge base. This may argue for the importance of early definitive education of neurosurgery residents in the core principles of ASD management. The Scoliosis Research Society and the AANS offer multiple deformity-focused courses targeted at residents and fellows to augment their formal training experience.

Completion of a spinal surgery fellowship was consistently associated with increased percentages of correct answers compared with the rates of those who had not completed a fellowship across all 5 categories. This demonstrates the importance of dedicated time in the field of spinal surgery. In general, fellows are involved in the more complex operations, but they also spend significant time evaluating spine patients in clinic, familiarizing themselves with the spine literature, and participating in spine-oriented research. The North American Spine Society explicitly includes spinal deformity in their guidelines for fellow education.7 Mazzola et al. surveyed 173 neurosurgeons applying for the American Board of Neurological Surgery oral board examination as to the reasons for pursuing fellowship training.9 Sixty percent of responders completed a fellowship of some type. Twenty-five percent of those indicated “perceived weakness” as a reason for pursuing fellowship. Although not specific to spinal surgery, it is possible that residents enter spinal surgery fellowship in part to gain expertise in deformity procedures that were not a significant component of their residency education. Of note is that while almost all orthopedic spine surgeons complete fellowships, the curricula vary with respect to adult and pediatric deformity experience, as in neurosurgery. It is unknown how orthopedic surgeons would fare on this survey.

Increased spinal surgery specialization was consistently associated with the largest increase in percent correct responses compared with the rates of respondents in less specialized practices across all categories. With the increase in volume of knowledge and implementation of new technology, neurosurgery is moving toward progressively greater subspecialization.4 Our data appear to argue that increased subspecialization within spinal surgery may be associated with an increase in ASD knowledge base. Mandating subspecialization within neurosurgery is a controversial issue, as it may have far-reaching effects on referral patterns and third-party oversight.4 Having self-identified the educational need, neurosurgeons who significantly specialize in spinal surgery may have taken greater advantage of spinal educational resources, such as society- and industry-sponsored deformity courses, but this was not directly assessed in the study. Clearly, more data are needed to answer this question.

The rates of correct responses on the individual question level were highly variable. The percentage correct ranged from 17% to 82%. This indicates that there are specific areas of strength and weakness within the neurosurgical ASD knowledge base. As a category, radiology and assessment of spinopelvic alignment appears to be an area of weakness. Our data suggest that neurosurgical knowledge can be augmented by increased specialization within one's practice, by completion of a spinal surgery fellowship, and, to some degree, by increased neurosurgical experience. Question 8, in particular, stands out, however, as it was associated with a very low correct response rate, which was not readily explained by any of the demographics. Our survey and future similar studies perhaps including more questions will help focus neurosurgical education on specific high yield areas within ASD surgery.

There are several limitations to our study. The response to the survey was not complete. It appears that with respect to experience, responder demographic characteristics were similar to those of the overall AANS membership. Although parallel data were not available for all AANS members, 36% of the AANS members consider their primary focus to be spine compared with 32% of responders who reported that at least 75% of their practice was focused on spinal surgery. Based on available data, the percentage of responders who had completed a spinal surgery fellowship was greater than for the AANS as a whole. Furthermore, a very low response rate was noted for highly specialized spine surgeons who would be expected to perform the best. Conversely, there was a high response rate for current trainees, who would be expected to perform worse. On the individual question level, each question was missing approximately 25% answers. This could bias our results, because if these questions were answered incorrectly, the percent correct would be significantly lower. As the survey was performed in an anonymous fashion, it is not possible to detail the demographic characteristics of the nonresponders to determine the possibility of selection bias. Our multiple-choice examination is not a validated metric. Diagnosis and management of ASD is exceedingly complex, and absolutely correct answers are often difficult to discern. It is not known if correct responses accurately reflect a surgeon's skill at deformity management or technique in the operating room. However, the questions were developed with the consensus of a group of experienced spinal deformity neurosurgeons and based exclusively on peer-reviewed data and widely accepted evaluation and management principles. Furthermore, we administered our survey to a panel of 10 experienced deformity surgeons, who performed reliably on the questions. Future studies may validate this as a valuable metric and include our orthopedic colleagues. An additional question could be added to determine whether the responder performs surgery for ASD in his or her practice. We were able to obtain a very large number of responses from the neurosurgical community in the United States and able to demonstrate strong associations between deformity knowledge base and several important demographic characteristics.

Conclusions

Spinal surgery is a major component of neurosurgery in the United States and internationally. Adult spinal deformity is an established cause of disability within a spinal neurosurgeon's practice. The results of our large survey demonstrate that knowledge of ASD surgery could be improved in neurosurgery. Within the neurosurgery knowledge base, certain areas of weakness have been identified based on the results of our survey. Neurosurgical education should particularly focus on radiology/spinopelvic alignment especially with respect to pelvic obliquity and coronal imbalance and operative techniques for ASD surgery.

Acknowledgments

We would like to thank Chris Ann Philips (Director, AANS Member Services) and Kathleen Craig (AANS Deputy Executive Director) for providing the demographic data on AANS membership.

Disclosure

Dr. Shaffrey reports a consultant relationship with Biomet, Globus, Medtronic, NuVasive, and Stryker as well as being a patent holder with and receiving royalties from Biomet and Medtronic. Dr. Ames reports a consultant relationship with DePuy, Stryker, and Medtronic; direct stock ownership with Visualase, Trans1, and Doctors Research Group; and receipt of royalties from Lanx and Aesculap. Dr. Smith reports a consultant relationship with Biomet, DePuy, Medtronic, and Globus as well as support of non–study-related clinical or research effort from DePuy. Dr. Koski reports a consultant relationship with Medtronic, NuVasive, Globus, and Spinewave as well as support of non–study-related clinical or research effort from Medtronic.

Author contributions to the study and manuscript preparation include the following. Conception and design: Ames, Koski, Rosner, Smith, Cheng, Shaffrey, McCormick. Acquisition of data: Ames, Clark, Keefe, Koski, Rosner, Smith, Cheng, Shaffrey, McCormick. Analysis and interpretation of data: all authors. Drafting the article: Ames, Clark, Garcia, Koski, Rosner, Smith, Cheng, Shaffrey, McCormick. Critically revising the article: Ames, Clark, Garcia, Koski, Rosner, Smith, Cheng, Shaffrey, McCormick. Reviewed submitted version of manuscript: Ames, Clark, Garcia, Koski, Rosner, Smith, Cheng, Shaffrey, McCormick. Statistical analysis: Ames, Clark, Garcia. Administrative/technical/material support: Ames, Keefe. Study supervision: Ames, Koski, Rosner, Smith, Cheng, Shaffrey, McCormick.

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Appendix

This article contains an appendix that is available only in the online version of the article.

Appendix 1 Spine Surgery Practice Survey

Questionnaire

Experience

Q1. How many years ago did you finish your training?

  • Still in training

  • Less than 5 years

  • 5–10 years

  • 10–15 years

  • More than 15 years

Training

Q2. Did you complete a spinal fellowship?

  • Yes

  • No

Specialization

Q3. What percentage of your practice is focused on spinal surgery?

  • 100%

  • 75–99%

  • 50–74%

  • 25–49%

  • less than 25%

Q4. In the standing xray of a 45 year old male with a solid fusion at L3-S1 and severe back pain, the radiographic finding which best indicates the likely origin of his symptoms is:

f6-spine121146
  • Disc degeneration at L2-3

  • Diffuse Osteoarthritis

  • Elevated Pelvic Tilt

  • Use of threaded cage

Q5. In this case of a healthy 55 year old male with spondylolisthesis in whom surgery is being planned, the next most appropriate diagnostic test is:

f7-spine121146
  • CT scan

  • Side bending xrays

  • Lateral standing 3 foot xray

  • DEXA scan

  • Thoracic MRI

Q6. In this patient referred for two level degenerative disease and low back pain the best operative strategy would be:

f8-spine121146
f9-spine121146
  • Two level in situ fusion

  • Two level instrumented fusion

  • Two level TLIF

  • Osteotomy

Q7. In this patient with severe LBP and prior lumbar fusion the most likely clinical abnormality is:

f10-spine121146
  • Pseudoarthrosis

  • Hip flexion contracture

  • Hardware fracture

  • Flat back

  • Spondylolisthesis

Q8. Full correction of this patient's thoracolumbar curve is likely to result in:

f11-spine121146
  • Stable coronal balance

  • Improved Coronal Balance

  • Coronal Imbalance

  • Sagittal imbalance

Q9. The outcome of this patient after surgery will depend on:

f12-spine121146
  • SVA less than 5cm

  • Pelvic Tilt less than 25 degrees

  • Pelvic incidence – lumbar lordosis < 11 degrees

  • T1 tilt angle

  • All of the above

Q10. In this 65 year old female with scoliosis, the factor which best predicts whether she will have surgery is:

f13-spine121146
  • Clinical deformity

  • Back pain VAS

  • Curve magnitude

  • Coronal balance

  • Preop disability

Q11. The normal lordosis of the L5-S1 disc space is:

  • 5 degrees

  • 10 degress

  • 20 degrees

  • More than 20 degrees

Q12. In fusing to the sacrum, pelvic fixation may be indicated in all of the following except:

  • Fusion terminating at L1

  • High grade spondylolisthesis

  • T3-S1 fusion for scoliosis

  • L5-S1 pseudoarthrosis

  • All of the above

Q13. In patients with a higher pelvic incidence:

  • More lumbar lordosis is required for normal standing balance

  • Less lumbar lordosis is required for normal standing balance

  • There is a higher incidence of spondylolisthesis

  • There is a lower incidence of spondylolistheis

  • A and C

  • B and C

Q14. The most likely diagnosis for the patient in this xray is:

f14-spine121146
  • Neuromuscular disease

  • Deconditioning

  • Iatrogenic sagittal imbalance

  • Myopathy

  • Next segment degeneration

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Article Information

Address correspondence to: Christopher P. Ames, M.D., University of California, San Francisco, Department of Neurological Surgery, 505 Parnassus Ave., Rm. M779, San Francisco, CA 94143-0112. email: amesc@neurosurg.ucsf.edu.

Please include this information when citing this paper: published online July 18, 2014; DOI: 10.3171/2014.5.SPINE121146.

© AANS, except where prohibited by US copyright law.

Headings

Figures

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    Representation of Question 6 and multiple-choice options. The CT scan demonstrates degenerative disc disease at L4–5 and L5–S1, while the 36-inch standing radiograph demonstrates a significantly elevated sagittal vertical axis (SVA), indicating the cause of the patient's low-back pain. The correct answer is in boldface. In this case, 3-column osteotomy is required to correct the sagittal imbalance. This question was categorized as radiology/spinopelvic alignment, HRQOL, surgical indications, and operative technique.

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    Representation of Question 10 and multiple-choice options. The correct answer is in boldface. Bess et al.3 showed, in a large multicenter retrospective analysis, that in older patients, such as the patient described in this question, surgical intervention is best predicted by preoperative disability. This question was categorized as HRQOL, surgical indications, and clinical evaluation.

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    Bar graph representation of percentage of correct answers for the overall survey comparing the different demographic groups of the responders. N = no; Y = yes.

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    Bar graphs depicting the differences among responder demographic groups for each of the question categories. The p values for significant differences are noted above the respective bars. Radiology/spinopelvic alignment questions are represented in A, HRQOL in B, surgical indications in C, operative technique in D, and clinical evaluation in E.

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    Representation of Question 8 and multiple-choice options (upper). The correct answer is in boldface. This question was categorized as radiology/spinopelvic alignment, HRQOL, operative technique, and clinical evaluation. This question was associated with a low percentage of correct answers and no statistically significant differences between any of the demographic categories, as shown in the graph (lower).

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References

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Benzel EC: The evolving presence of spinal neurosurgery in the spectrum of neurological surgery. Neurosurgery 60:5915922007

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Bess SBoachie-Adjei OBurton DCunningham MShaffrey CShelokov A: Pain and disability determine treatment modality for older patients with adult scoliosis, while deformity guides treatment for younger patients. Spine (Phila Pa 1976) 34:218621902009

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Couldwell WTRovit RL: Rethinking neurosurgical subspecialization. Surg Neurol 58:3593702002

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Friedlich DLFeustel PJPopp AJ: Workforce demand for neurosurgeons in the United States of America: a 13-year retrospective study. J Neurosurg 90:9939971999

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Herkowitz HNConnolly PJGundry CRVarlotta GPZdeblick TATruumees E: Resident and fellowship guidelines: educational guidelines for resident training in spinal surgery. Spine (Phila Pa 1976) 25:270327072000

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Lee TTKlose JL: Survey on neurosurgery subspecialty fellowship training. Surg Neurol 52:6416451999

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