Variation in outcomes across centers after surgery for lumbar stenosis and degenerative spondylolisthesis in the spine patient outcomes research trial

Effect of Mixture of Recombinant Human Bone Morphogenic Protein-2 and Demineralized Bone Matrix in Lateral Lumbar Interbody Fusion

OBJECTIVE

This study aims to determine the optimal dose of recombinant-human bone morphogenic protein-2 (rhBMP-2) for successful bone fusion in minimally invasive lateral lumbar interbody fusion (MIS LLIF). Previous studies show that rhBMP is an effective alternative to autologous iliac crest bone graft, but the optimal dose remains uncertain. The study analyzes the fusion rates associated with different rhBMP doses to provide a recommendation for the optimal dose in MIS LLIF.

METHODS

Ninety-three patients underwent MIS LLIF using demineralized bone matrix (DBM) or a mixture of rhBMP-2 and DBM as fusion material. The group was divided into the following three groups according to the rhBMP-2 usage : group A, only DBM was used (n=27); group B, 1 mg of rhBMP-2 per 5 mL of DBM paste (n=41); and group C, 2 mg of rhBMP-2 per 5 mL of DBM paste (n=25). Demographic data, clinical outcomes, postoperative complication and fusion were assessed.

RESULTS

At 12 months post-surgery, the overall fusion rate was 92.3% according to Bridwell fusion grading system. Groups B and C, who received rhBMP-2, had significantly higher fusion rates than group A, who received only DBM. However, there was no significant increase in fusion rate when the rhBMP-2 dosage was increased from group B to group C. The groups B and C showed significant improvement in back pain and Oswestry disability index compared to the group A. The incidence of screw loosening was decreased in groups B and C, but there was no significant difference in the occurrence of other complications.

CONCLUSION

Usage of rhBMP-2 in LLIF surgery leads to early and increased final fusion rates, which can result in faster pain relief and return to daily activities for patients. The benefits of using rhBMP-2 were not significantly different between the groups that received 1 mg/5 mL and 2 mg/5 mL of rhBMP-2. Therefore, it is recommended to use 1 mg of rhBMP-2 with 5 mL of DBM, taking both economic and clinical aspects into consideration.

Variations in surgical practice and short-term outcomes for degenerative lumbar scoliosis and spondylolisthesis: do surgeon training and experience matter?

For diverse procedures, sizable geographic variation exists in rates and outcomes of surgery, including for degenerative lumbar spine conditions. Little is known about how surgeon training and experience are associated with surgeon-level variations in spine surgery practice and short-term outcomes. This retrospective observational analysis characterized variations in surgical operations for degenerative lumbar scoliosis or spondylolisthesis, two common age-related conditions. The study setting was two large spine surgery centers in one region during 2017-19. Using data (International Classification of Diseases-10th edition and current procedural terminology codes) extracted from electronic health record systems, we characterized surgeon-level variations in practice (use of instrumented fusion - a more extensive procedure that involves device-related risks) and short-term postoperative outcomes (major in-hospital complications and readmissions). Next, we tested for associations between surgeon training (specialty and spine fellowship) and experience (career stage and operative volume) and use of instrumented fusion as well as outcomes. Eighty-nine surgeons performed 2481 eligible operations. For the study diagnoses, spine surgeons exhibited substantial variation in operative volume, use of instrumented fusion, and postoperative outcomes. Among surgeons above the median operative volume, use of instrumented fusion ranged from 0% to >90% for scoliosis and 9% to 100% for spondylolisthesis, while rates of major in-hospital complications ranged from 0% to 25% for scoliosis and from 0% to 14% for spondylolisthesis. For scoliosis, orthopedic surgeons were more likely than neurosurgeons to perform instrumented fusion for scoliosis [49% vs. 33%, odds ratio (OR) = 2.3, 95% confidence interval (95% CI) 1.3-4.2, P-value = .006] as were fellowship-trained surgeons (49% vs. 25%, OR = 3.0, 95% CI 1.6-5.8; P = .001). Fellowship-trained surgeons had lower readmission rates. Surgeons with higher operative volumes used instrumented fusion more often (OR = 1.1, 95% CI 1.0-1.2, P < .05 for both diagnoses) and had lower rates of major in-hospital complications (OR = 0.91, 95% CI 0.85-0.97; P = .006). Surgical practice can vary greatly for degenerative spine conditions, even within the same region and among colleagues at the same institution. Surgical specialty and subspecialty, in addition to recent operative volume, can be linked to variations in spine surgeons' practice patterns and outcomes. These findings reinforce the notion that residency and fellowship training may contribute to variation and present important opportunities to optimize surgical practice over the course of surgeons' careers. Future efforts to reduce unexplained variation in surgical practice could test interventions focused on graduate medical education. Graphical Abstract.

Different Approaches for Case-Mix Adjustment of Patient-Reported Outcomes to Compare Healthcare Providers-Methodological Results of a Systematic Review

Simple Summary

Patient-reported outcomes need to be reported with case-mix adjustment in order to allow fair comparison between healthcare providers. This systematic review identified different approaches to case-mix adjustment, with wide variation between the various approaches.

Abstract

Patient-reported outcomes (PROs) are increasingly being used to compare the quality of outcomes between different healthcare providers (medical practices, hospitals, rehabilitation facilities). However, such comparisons can only be fair if differences in the case-mix between different types of provider are taken into account. This can be achieved with adequate statistical case-mix adjustment (CMA). To date, there is a lack of overview studies on current CMA methods for PROs. The aim of this study was to investigate which approaches are currently used to report and examine PROs for case-mix-adjusted comparison between providers. A systematic MEDLINE literature search was conducted (February 2021). The results were examined by two reviewers. Articles were included if they compared (a) different healthcare providers using (b) case-mix-adjusted (c) patient-reported outcomes (all AND conditions). From 640 hits obtained, 11 articles were included in the analysis. A wide variety of patient characteristics were used as adjustors, and baseline PRO scores and basic sociodemographic and clinical information were included in all models. Overall, the adjustment models used vary considerably. This evaluation is an initial attempt to systematically investigate different CMA approaches for PROs. As a standardized approach has not yet been established, we suggest creating a consensus-based methodological guideline for case-mix adjustment of PROs.

Physician-Related Variability in the Outcomes of an Invasive Treatment for Neck and Back Pain: A Multi-Level Analysis of Data Gathered in Routine Clinical Practice

Neuro-reflexotherapy (NRT) is a proven effective, invasive treatment for neck and back pain. To assess physician-related variability in results, data from post-implementation surveillance of 9023 patients treated within the Spanish National Health Service by 12 physicians were analyzed. Separate multi-level logistic regression models were developed for spinal pain (SP), referred pain (RP), and disability. The models included all patient-related variables predicting response to NRT and physician-related variables. The Intraclass Correlation Coefficient (ICC) and the Median Odds Ratio (MOR) were calculated. Adjusted MOR (95% CI) was 1.70 (1.47; 2.09) for SP, 1.60 (1.38; 1.99) for RP, and 1.65 (1.42; 2.03) for disability. Adjusted ICC (95%CI) values were 0.08 (0.05; 0.15) for SP, 0.07 (0.03; 0.14) for RP, and 0.08 (0.04; 0.14) for disability. In the sensitivity analysis, in which the 6920 patients treated during the physicians’ training period were excluded, adjusted MOR was 1.38 (1.17; 1.98) for SP, 1.37 (1.12; 2.31) for RP, and 1.25 (1.09; 1.79) for disability, while ICCs were 0.03 (0.01; 0.14) for SP, 0.03 (0.00; 0.19) for RP, and 0.02 (0.00; 0.10) for disability. In conclusion, the variability in results obtained by different NRT-certified specialists is reasonable. This suggests that current training standards are appropriate.

Association between the appropriateness of surgery, according to appropriate use criteria, and patient-rated outcomes after surgery for lumbar degenerative spondylolisthesis

INTRODUCTION

Treatment failures in spine surgery are often attributable to poor patient selection and the application of inappropriate treatment. We used published appropriate use criteria (AUC) to evaluate the appropriateness of surgery in a large group of patients operated for lumbar degenerative spondylolisthesis (LDS) and to evaluate its association with outcome.

METHODS

This was a retrospective analysis of prospectively collected outcome data from patients operated in our Spine Centre, 2005-2012. Appropriateness of surgery was judged based on the AUC. Patients had completed the multidimensional Core Outcome Measures Index (COMI) before surgery and at 3 months' and 1, 2 and 5 years' follow-up (FU).

RESULTS

In total, 448 patients (69.8 ± 9.6 years; 323 (72%) women) were eligible for inclusion and the AUC could be applied in 393 (88%) of these. Surgery was considered appropriate (A) in 234 (59%) of the patients, uncertain/equivocal (U) in 90 (23%) and inappropriate (I) in 69 (18%). A/U patients had significantly (p < 0.05) greater improvements in COMI than I patients at each FU time point. The minimal clinically important change (MCIC) score for COMI was reached by 82% A, 76% U and 54% I patients at 1-year FU (p < 0.001, I vs A and U); the odds of achieving MCIC were 3-4 times greater in A/U patients than in I patients.

CONCLUSIONS

The results suggest a relationship between appropriateness of surgery for LDS and the improvements in COMI score after surgery. The findings require confirmation in prospective studies that also include a control group of non-operated patients.

Variation in complications and mortality following ALPPS at early-adopting centers

BACKGROUND

Various, often conflicting, estimates for post-operative morbidity and mortality following ALPPS have been reported in the literature, suggesting that considerable center-level variation exists. Some of this variation may be related to center volume and experience.

METHODS

Using data from seventeen centers who were early adopters of the ALPPS technique, we estimated the variation, by center, in standardized 90-day mortality and comprehensive complication index (CCI) for patients treated between 2012 and 2018.

RESULTS

We estimated that center-specific 90-day mortality following treatment with ALPPS varied from 4.2% (95% CI: 0.8, 9.9) to 29.1% (95% CI: 13.9, 50.9), and that center-specific CCI following treatment with ALPPS varied from 17.0 (95% CI: 7.5, 26.5) to 49.8 (95% CI: 38.1, 61.8). Declines in estimated 90-day mortality and CCI were observed over time, and almost all individual centers followed this trend. Patients treated at centers with a higher number of ALPPS cases performed over the prior year had a lower risk of post-operative mortality.

CONCLUSION

Despite considerable center-level variation in ALPPS outcomes, perioperative outcomes following ALPPS have improved over time and treatment at higher volume centers results in a lower risk of 90-day mortality. Morbidity and mortality remain concerningly high at some centers.

Analyzing the Correlation Between Surgeon Experience and Patient Length of Hospital Stay

Introduction  Many clinical, social, and even economic factors have been extensively analyzed in the literature and shown to influence the length of stay (LOS) after spinal procedures. However, surgeon's experience was mostly examined relative to a learning curve and not regarding the time in practice. The primary objective of this study was to determine the effect of one surgeon's experience on the LOS in patients undergoing one- to two-level transforaminal lumbar interbody fusions (TLIFs). Materials and Methods  The study design was a retrospective cohort study of hospital discharge data. The cohort was comprised of 240 consecutive patients who had undergone open one- or two-level elective TLIF procedures for lumbar degenerative disc disease. The primary predictor was the surgeon's experience based upon the years of practice. The primary outcome was LOS, which was controlled by the discharge criteria that remained consistent throughout the study. Results  Based on the Poisson regression model, it can be inferred that the LOS is not significantly associated with a surgeon's experience (Pr(>|t|) = 0.8985, CI: -0.5825 to 0.5114) while controlling for all other variables. Other independent factors did seem to significantly influence patients' LOS, including the admission type (Pr(>|t|) = 9.637^-08, CI: -0.8186 to -0.3786), the number of TLIF levels (Pr(>|t|) = 1.721^-06, CI: 0.0606 to 0.1446), the Clavien-Dindo ( Pr(>|t|) = 0, CI: 0.1489 to 0.1494), the American Society of Anesthesiologists (ASA) physical status classification scores (Pr(>|t|) = 4.878^-3, CI: 0.0336 to 0.1880), and being discharged to skilled nursing facility (Pr(>|t|) = 3.44^-2, CI: 0.0127 to 0.3339). Conclusions Based upon the years in practice, surgeon experience was not associated with length of hospitalization and estimated blood loss during surgery in patients undergoing one- and two-level TLIF surgeries. However, while controlling for all other variables, the surgeon's experience and surgical time had a highly significant correlation. The study results clearly demonstrated efficiency, but we did not identify a clear correlation between LOS and surgeon experience overtime suggesting that other factors are likely contributing to such outcome. The average LOS is a complex measure of healthcare resource use and hospital discharge policy or other variables are likely having more effect on LOS than individual surgeons' preferences.

Management of Incidental Durotomy: Results from a Nationwide Survey Conducted by the French Society of Spine Surgery

OBJECTIVE

To obtain real-life data on the most common practices used for management of incidental durotomy (ID) in France.

METHODS

Data were collected from spinal surgeons using a practice-based online questionnaire. The survey comprised 31 questions on the current management of ID in France. The primary outcome was the identification of areas of consensus and uncertainty on ID follow-up.

RESULTS

A total of 217 surgeons (mainly orthopaedic surgeons and neurosurgeons) completed the questionnaire and were included in the analysis. There was a consensus on ID repair with 94.5% of the surgeons considering that an ID should always be repaired, if repairable, and 97.2% performing a repair if an ID occurred. The most popular techniques were simple suture or locked continuous suture (48.3% vs. 57.8% of surgeons). Nonrepairable IDs were more likely to be treated with surgical sealants than with an endogenous graft (84.9% vs. 75.5%). Almost two thirds of surgeons (71.6%) who adapted their standard postoperative protocol after an ID recommended bed rest in the supine position. Among these, 48.8% recommended 24 hours of bed rest, while 53.5% recommended 48 hours of bed rest. The surgeons considered that the main risk factors for ID were revision surgery (98.6%), patient's age (46.8%), surgeon's exhaustion (46.3%), and patient's weight (21.3%).

CONCLUSIONS

This nationwide survey reflects the lack of a standardized management protocol for ID. Practices among surgeons remain very heterogeneous. Further consensus studies are required to develop a standard management protocol for ID.

Hospital and Surgeon Variation in Patient-reported Functional Outcomes After Lumbar Spine Fusion: A Statewide Evaluation

STUDY DESIGN

Statewide retrospective cohort study using prospectively collected data from the Spine Care and Outcomes Assessment Program, capturing ∼75% of the state's spine fusion procedures.

OBJECTIVE

The aim of this study was to estimate the variation in patient-reported outcomes (PROs) 1 year after elective lumbar fusion surgery across surgeons and hospitals; and to discuss the potential impact of guiding patient selection using a PRO prediction tool.

SUMMARY OF BACKGROUND DATA

Despite an increasing interest in incorporating PROs as part of the move toward value-based payment and to improve quality, limited evidence exists on how PROs vary across hospitals and surgeons, a key aspect of using these metrics for quality profiling.

METHODS

We examined patient-reported functional improvement (≥15-point reduction in the Oswestry Disability Index [ODI]) and minimal disability (reaching ≤22 on the ODI) 1 year after surgery in 17 hospitals and 58 surgeons between 2012 and 2017. Outcomes were risk-adjusted for patient characteristics with multiple logistic regressions and reliability-adjusted using hierarchical models.

RESULTS

Of the 737 patients who underwent lumbar fusion (mean [SD] age, 63 [12] years; 60% female; 84% had stenosis; 70% had spondylolisthesis), 58.7% achieved functional improvement and 42.5% reached minimal disability status at 1 year. After adjusting for patient factors, there was little variation between hospitals and surgeons (maximum interclass correlation was 3.5%), and this variation became statistically insignificant after further reliability adjustment. Avoiding operation on patients with <50% chance of functional improvement may reduce current surgical volume by 63%.

CONCLUSION

Variations in PROs across hospitals and surgeons were mainly driven by differences in patient populations undergoing lumbar fusion, suggesting that PROs may not be useful indicators of hospital or surgeon quality. Careful patient selection using validated prediction tools may decrease differences in outcomes across hospitals and providers and improve overall quality, but would significantly reduce surgical volumes.

LEVEL OF EVIDENCE

3.

SpineCloud: image analytics for predictive modeling of spine surgery outcomes

Purpose: Data-intensive modeling could provide insight on the broad variability in outcomes in spine surgery. Previous studies were limited to analysis of demographic and clinical characteristics. We report an analytic framework called "SpineCloud" that incorporates quantitative features extracted from perioperative images to predict spine surgery outcome. Approach: A retrospective study was conducted in which patient demographics, imaging, and outcome data were collected. Image features were automatically computed from perioperative CT. Postoperative 3- and 12-month functional and pain outcomes were analyzed in terms of improvement relative to the preoperative state. A boosted decision tree classifier was trained to predict outcome using demographic and image features as predictor variables. Predictions were computed based on SpineCloud and conventional demographic models, and features associated with poor outcome were identified from weighting terms evident in the boosted tree. Results: Neither approach was predictive of 3- or 12-month outcomes based on preoperative data alone in the current, preliminary study. However, SpineCloud predictions incorporating image features obtained during and immediately following surgery (i.e., intraoperative and immediate postoperative images) exhibited significant improvement in area under the receiver operating characteristic (AUC): AUC = 0.72 ( CI 95 = 0.59 to 0.83) at 3 months and AUC = 0.69 ( CI 95 = 0.55 to 0.82) at 12 months. Conclusions: Predictive modeling of lumbar spine surgery outcomes was improved by incorporation of image-based features compared to analysis based on conventional demographic data. The SpineCloud framework could improve understanding of factors underlying outcome variability and warrants further investigation and validation in a larger patient cohort.

Validation of the LOCOMO-25 and its minimum clinically important differences in domain scores for Chinese patients with low back pain and neck pain

BACKGROUND

The 25-question Geriatric Locomotive Function Scale (LOCOMO-25) was developed to assess any decline in mobility functions. This study aims to validate the LOCOMO-25 in Chinese patients with chronic low back pain and/or neck pain.

METHODS

Adult patients with chronic low back pain and/or neck pain completed the LOCOMO-25, SF-36, EQ-5D-5L, ODI, VAS and/or NDI. Internal consistency was assessed by Cronbach's alpha coefficient (α). Test-retest reliability was assessed by intra-class correlation coefficients. Construct validity was assessed by Spearman correlation tests against other outcome measures. Sensitivity to detect differences between groups was assessed by Mann-Whitney U or Kruskal-Wallis H test, where appropriate. Intergroup comparison was performed further in terms of domain scores and their changes at test-retest.

RESULTS

A total of 111 patients were consecutively recruited. LOCOMO-25 demonstrated excellent internal consistency (α = 0.915) and test-retest reliability (Intraclass correlation: 0.705 to 0.826). LOCOMO-25 was significantly correlated with all domains of SF-36, EQ-5D, ODI, NDI, and VAS (p < 0.01). It was found to be sensitive in differentiating between patients with neural compression (32.8 ± 16.9) and without (21.2 ± 12.7), with history of fall(s) within the previous one year (30.8 ± 16.0) and without (24.2 ± 15.1), requires assistive devices for ambulation (40.6 ± 21.6) or independent (23.6 ± 13.1) and various pain levels (mild: 17.2 ± 10.6; moderate: 23.5 ± 11.7; severe: 38.5 ± 16.5). Patients with neural compression scored significantly higher in the domain of pain and patients requiring assistive devices for ambulation scored significantly higher in the domains of ADL and social functions. The minimum detectable differences for various domains of the LOCOMO-25 score included pain (2.76), activities of daily living (6.07), social function (1.59), and mental health status (2.06).

CONCLUSIONS

LOCOMO-25 has been validated in Chinese patients with chronic low back and neck pain with satisfactory psychometric properties, and with individual domain minimum clinically important differences. There is adequate internal consistency, test-retest reliability, construct validity and sensitivity to detect differences between patients with/without neural compression, different ambulatory statuses and pain severity.

The Effect of Symptom Duration on Outcomes After Fusion for Degenerative Spondylolisthesis

STUDY DESIGN

Longitudinal comparative cohort.

OBJECTIVES

To determine if the duration of symptoms in patients with degenerative spondylolisthesis affects postoperative outcomes after 1- or 2-level decompression and fusion.

METHODS

Patients undergoing primary surgery for grade 1 degenerative spondylolisthesis at a single Quality Outcomes Database (QOD) participating site were identified. Demographic, surgical and patient-reported outcomes (PROs) data, including baseline and 12-month postoperative Oswestry Disability Index (ODI), back pain (BP, 0-10), leg pain (LP, 0-10), and EuroQOL-5D (EQ-5D) scores were collected. Individual medical records were reviewed for data on duration of symptoms prior to surgery. Patients were stratified into 3 cohorts-those with preoperative symptom duration of less than 1 year, 1 to 2 years, or greater than 2 years.

RESULTS

Complete data was available in 123 patients. Significant improvement in ODI, BP, and LP scores were observed in all groups. At 12-month follow-up improvement in ODI, BP, or LP was similar among the cohorts; with a trend toward significance with better improvement in LP scores in patients with a symptom duration of less than 1 year to those with symptom duration greater than 2 years (P = .058).

CONCLUSIONS

The duration of symptoms up to 2 years prior to surgery may not be a useful predictor of improvement of back pain or disability scores in patients with spondylolisthesis requiring decompression and fusion. Although there was a positive trend for improvement in leg pain for those with a shorter duration of symptoms, this did not reach statistical significance in our study.

Impact of Multidisciplinary Spine Conferences on Surgical Planning and Perioperative Care in Elective Lumbar Spine Surgeries

Study Design

Pre- and post-implementation analysis.

Purpose

We examined the impact of implementing multidisciplinary spine conferences—“spine board” reviews—on the general utilization of elective lumbar spine surgeries in a tertiary medical institute.

Overview of Literature

A multidisciplinary approach to spine care reportedly improves the appropriate utilization of surgical spine procedures.

Methods

A multidisciplinary spine board was established to review candidates selected for elective lumbar spine surgery. The board comprised representatives from orthopedic spine surgery, neurosurgery, psychology, physical therapy, radiology, pharmacy, primary care, pain management, anesthesiology, and veteran advocacy. Two similar 6-month periods were selected to study the impact of this implementation: pre-implementing (June 1, 2015 to November 30, 2015) and post-implementation (June 1, 2016 to November 30, 2016) periods.

Results

Between March 1, 2016 and December 30, 2016, the spine board discussed 11 patients. All patients underwent clinical examinations and radiological assessments findings that warranted elective lumbar surgery. The board recommended non-surgical interventions before proceeding with the planned surgeries in all cases. In the pre-implementation period, a total of 101 elective lumbar spine surgeries were performed. In the post-implementation period, a total of 51 elective lumbar spine surgeries were performed (p<0.05). The surgical plan for elective lumbar spine surgery in the post-implementation period was not directly influenced by the review of spine board because none of the cases were discussed in the conferences; however, the care occurred at a hospital where the spine board was implemented. There was no significant change in the number of cervical spine surgeries performed (66 preimplementation vs. 56 post-implementation). The average surgery duration was 52 minutes shorter in the post-implementation period compared with that in the pre-implementation period (p<0.05).

Conclusions

Implementation of a multidisciplinary spine board was concurrent with an overall decrease in the utilization of lumbar spine surgeries for elective cases of low back pain in a tertiary medical center.

Indication Variability in Degenerative Lumbar Spine Surgery: A Four-nation Survey

STUDY DESIGN

Electronic survey.

OBJECTIVE

The aim of this study was to identify the international nuances in surgical treatment patterns for severals lumbar degenerative conditions, specifically, to identify differences in responses in each country groupand different treatment trends across countries.

SUMMARY OF BACKGROUND DATA

Significant variations in treatment of lumbar degenerative conditions exist among spine surgeons, related to the lack of established consensus in the literature.

METHODS

An online survey with preformulated answers was submitted to 52 orthopedic surgeons, 50 neurosurgeons from four different countries (United States, France, Spain, and Germany) regarding five vignette-cases. Cases included: multilevel stenosis, monolevel stenosis, lytic spondylolisthesis, isthmic lysis, and degenerative scoliosis. The variability for each country was calculated according to the Index of Qualitative Variation (IQV = 0: no variability and 1: maximal variability). We used Fleiss kappa (range: from -1, poor agreement, to 1, almost perfect agreement) for assessing the reliability of agreement between the participants concerning specialties, countries, and age groups.

RESULTS

For the two stenosis cases, US surgeons were more likely to propose decompression (IQV multilevel = 0.47 and monolevel = 0.32) comparing with European countries more heterogeneous (all IQV >0.70) and more frequently proposing fusion. As regards degenerative scoliosis, all attitudes were extremely heterogeneous with IQV >0.8. Fusion for isthmic spondylolisthesis was more consensual (all IQV <0.63), but attitudes were more heterogeneous for isthmic lysis (IQV ranged from 0.48 to 0.76) with anterior approach proposed in France (37%) and United States (19.2%).The overall interrater agreement was equally slight not only for neurosurgeons (Fleiss Kappa = 0.04) and orthopedic surgeons (Kappa = 0.13), but also for countries (Kappa <0.13) and age groups (Kappa <0.1).

CONCLUSION

In this study, we found substantial agreement for some spinal conditions but a high variability in some others: intranational and international variations were observed, reflecting the lack of literature consensus.

LEVEL OF EVIDENCE

2.

Do Demographic Factors of Spine Surgeons Affect the Rate at Which Spinal Fusion Is Performed on Patients?

STUDY DESIGN

Retrospective study.

OBJECTIVE

The purpose of this study was to evaluate associations between spine surgeon demographics and the rate at which elective spine fusion is performed.

SUMMARY OF BACKGROUND DATA

Rapidly increasing rates of elective spinal fusion in the United States have given rise to important questions about what factors may drive spine surgeon decision making.

METHODS

Publicly available spine surgeon practice pattern data from Centers for Medicare and Medicaid Services were reviewed retrospectively. Fusion rate was defined as the number of fusion procedures performed on Medicare beneficiaries by a surgeon per total number of unique Medicare beneficiaries seen. Inclusion criteria were neurological or orthopedic spine surgeons who performed 11 or more separate spine fusion procedures on Medicare patients between 2011 and 2013 as defined by this database. Demographic information was collected from public record. The increased probability of a surgeon performing spine fusion was assessed using a relative risk (RR) and corresponding 95% confidence interval (CI).

RESULTS

A total of 3979 spine surgeons who practice in the United States and performed spine fusion on 171,676 Medicare patients from 2011 to 2013 met the inclusion criteria. The average rate of spine fusion for surgeons in this database was 7.5%. Surgeons with higher fusion rates practiced in an academic versus private setting (RR = 1.44, 95% CI [1.35-1.53]; P < 0.0001), were more likely neurological versus orthopedic surgeons (RR = 1.10, 95% CI [1.05-1.15]; P < 0.0001), and practiced in the West versus Midwest, South, and Northeast region of the United States (RR = 1.20, 95% CI [1.14-1.27]; P < 0.0001). Number of years in practice was significantly associated negatively with fusion rate (P < 0.0001).

CONCLUSION

Significant variation in the rate of spine fusion based on practice type, training, region, and experience suggests poor consensus on indications for this procedure. Knowledge of these relationships may help identify underlying reasons for variations in surgical care and improve surgical outcomes.

LEVEL OF EVIDENCE

3.

Why Do Patients Seek a Spine Surgeon?

STUDY DESIGN

Retrospective review of chief complaints (CCs) of patients seeking care at a specialty spine clinic with the diagnosis of degenerative scoliosis or lumbar stenosis.

OBJECTIVES

The purpose of the study was to ascertain why patients seek care from spine surgeons. Specifically, we asked whether pain or deformity was more common. Secondarily, we studied the correlation of progressive curve magnitude with perceived functionality.

BACKGROUND

Scant research is available on what leads a patient to be seen in a clinic. Degenerative scoliosis is often correlated with pain in the low back and extremities, symptoms that impinge on quality of life in the elderly. Some research suggests there is no correlation between progressive curve magnitude and perceived functionality.

METHODS

Charts and radiographs of 351 consecutive patients were reviewed. Patient inclusion criteria were as follows: 1) they were seen at our spine clinic in one 12-month period, 2) their chief diagnosis was degenerative scoliosis or lumbar stenosis, 3) they were 50 years of age or older, and 4) they had no known prior history of scoliosis. Oswestry Disability Index (ODI) data were recorded.

RESULTS

Of 351 patients, 160 reported their CC was combination back + leg pain on the initial visit survey, 123 complained of back pain only, and 42 complained of leg pain only. Ten complained of deformity or deformity + pain. Patients with degenerative scoliosis + spinal stenosis represented 25% of the study population; 11% were diagnosed with degenerative scoliosis only; 64% with stenosis only. Of the 122 patients with a Cobb angle of greater than 10°, only 10 complained of deformity or deformity + pain on the initial visit survey.

CONCLUSIONS

Patients most often presented because of pain, specifically back, leg, or a combination of both. Patients seldom complained of deformity only, even among patients exhibiting a Cobb angle of greater than 30 degrees.

Patient-specific factors affecting hospital costs in lumbar spine surgery

OBJECT

Health care-related costs after lumbar spine surgery vary depending on procedure type and patient characteristics. Age, body mass index (BMI), number of spinal levels, and presence of comorbidities probably have significant effects on overall costs. The present study assessed the impact of patient characteristics on hospital costs in patients undergoing elective lumbar decompressive spine surgery.

METHODS

This study was a retrospective review of elective lumbar decompression surgeries, with a focus on specific patient characteristics to determine which factors drive postoperative, hospital-related costs. Records between January 2010 and July 2012 were searched retrospectively. Only elective lumbar decompressions including discectomy or laminectomy were included. Cost data were obtained using a database that allows standardization of a list of hospital costs to the fiscal year 2013–2014. The relationship between cost and patient factors including age, BMI, and American Society of Anesthesiologists (ASA) Physical Status Classification System grade were analyzed using Student t-tests, ANOVA, and multivariate regression analyses.

RESULTS

There were 1201 patients included in the analysis, with a mean age of 61.6 years. Sixty percent of patients in the study were male. Laminectomies were performed in 557 patients (46%) and discectomies in 644 (54%). Laminectomies led to an increased hospital stay of 1.4 days (p < 0.001) and increased hospital costs by $1523 (p < 0.001) when compared with discectomies. For laminectomies, age, BMI, ASA grade, number of levels, and durotomy all led to significantly increased hospital costs and length of stay on univariate analysis, but ASA grade and presence of a durotomy did not maintain significance on multivariate analysis for hospital costs. For a laminectomy, patient age ≥ 65 years was associated with a 0.6-day increased length of stay and a $945 increase in hospital costs when compared with patient age < 65 years (p < 0.001). A durotomy during a laminectomy increased length of stay by 1.0 day and increased hospital costs by $1382 (p < 0.03). For discectomies, age, ASA grade, and durotomy were significantly associated with increased hospital costs on univariate analysis, but BMI was not. Only age and presence of a durotomy maintained significance on multivariate analysis. There was a significant increase in hospital length of stay in patients undergoing discectomy with increasing age, BMI, ASA grade, and presence of a durotomy on univariate analysis. However, only age and presence of a durotomy maintained significance on multivariate analysis. For discectomies, age ≥ 65 years was associated with a 0.7-day increased length of stay (p < 0.001) and an increase of $931 in postoperative hospital costs (p < 0.01) when compared with age < 65 years.

CONCLUSIONS

Patient factors such as age, BMI, and comorbidities have significant and measurable effects on the postoperative hospital costs of elective lumbar decompression spinal surgeries. Knowledge of how these factors affect costs will become important as reimbursement models change.

Evidence and practice in spine registries

BACKGROUND AND PURPOSE

We performed a systematic review and a survey in order to (1) evaluate the evidence for the impact of spine registries on the quality of spine care, and with that, on patient-related outcomes, and (2) evaluate the methodology used to organize, analyze, and report the "quality of spine care" from spine registries.

METHODS

To study the impact, the literature on all spinal disorders was searched. To study methodology, the search was restricted to degenerative spinal disorders. The risk of bias in the studies included was assessed with the Newcastle-Ottawa scale. Additionally, a survey among registry representatives was performed to acquire information about the methodology and practice of existing registries.

RESULTS

4,273 unique references up to May 2014 were identified, and 1,210 were eligible for screening and assessment. No studies on impact were identified, but 34 studies were identified to study the methodology. Half of these studies (17 of the 34) were judged to have a high risk of bias. The survey identified 25 spine registries, representing 14 countries. The organization of these registries, methods used, analytical approaches, and dissemination of results are presented.

INTERPRETATION

We found a lack of evidence that registries have had an impact on the quality of spine care, regardless of whether intervention was non-surgical and/or surgical. To improve the quality of evidence published with registry data, we present several recommendations. Application of these recommendations could lead to registries showing trends, monitoring the quality of spine care given, and ultimately improving the value of the care given to patients with degenerative spinal disorders.

Unintended durotomy in lumbar degenerative spinal surgery: a 10-year systematic review of the literature

OBJECT

Unintended durotomy is a common occurrence during lumbar spinal surgery, particularly in surgery for degenerative spinal conditions, with the reported incidence rate ranging from 0.3% to 35%. The authors performed a systematic literature review on unintended lumbar spine durotomy, specifically aiming to identify the incidence of durotomy during spinal surgery for lumbar degenerative conditions. In addition, the authors analyzed the incidence of durotomy when minimally invasive surgical approaches were used as compared with that following a traditional midline open approach.

METHODS

A MEDLINE search using the term “lumbar durotomy” (under the 2015 medical subject heading [MeSH] “cerebrospinal fluid leak”) was conducted on May 13, 2015, for English-language medical literature published in the period from January 1, 2005, to May 13, 2015. The resulting papers were categorized into 3 groups: 1) those that evaluated unintended durotomy rates during open-approach lumbar spinal surgery, 2) those that evaluated unintended durotomy rates during minimally invasive spine surgery (MISS), and 3) those that evaluated durotomy rates in comparable cohorts undergoing MISS versus open-approach lumbar procedures for similar lumbar pathology.

RESULTS

The MEDLINE search yielded 116 results. A review of titles produced 22 potentially relevant studies that described open surgical procedures. After a thorough review of individual papers, 19 studies (comprising 15,965 patients) pertaining to durotomy rates during open-approach lumbar surgery were included for analysis. Using the Oxford Centre for Evidence-Based Medicine (CEBM) ranking criteria, there were 7 Level 3 prospective studies and 12 Level 4 retrospective studies. In addition, the authors also included 6 studies (with a total of 1334 patients) that detailed rates of durotomy during minimally invasive surgery for lumbar degenerative disease. In the MISS analysis, there were 2 prospective and 4 retrospective studies. Finally, the authors included 5 studies (with a total of 1364 patients) that directly compared durotomy rates during open-approach versus minimally invasive procedures. Studies of open-approach surgery for lumbar degenerative disease reported a total of 1031 durotomies across all procedures, for an overall durotomy rate of 8.11% (range 2%–20%). Prospectively designed studies reported a higher rate of durotomy than retrospective studies (9.57% vs 4.32%, p = 0.05). Selected MISS studies reported a total of 93 durotomies for a combined durotomy rate of 6.78%. In studies of matched cohorts comparing open-approach surgery with MISS, the durotomy rates were 7.20% (34 durotomies) and 7.02% (68), respectively, which were not significantly different.

CONCLUSIONS

Spinal surgery for lumbar degenerative disease carries a significant rate of unintended durotomy, regardless of the surgical approach selected by the surgeon. Interpretation of unintended durotomy rates for lumbar surgery is limited by a lack of prospective and cohort-matched controlled studies.

Microsurgical decompression for central lumbar spinal stenosis: a single-center observational study

OBJECTIVE

To assess outcomes and complications in patients undergoing microsurgical decompression for central lumbar spinal stenosis (LSS) without radiologic instability.

METHODS

Prospective data for patients operated at the Department of Neurosurgery, St. Olavs University Hospital, Norway, were obtained from the Norwegian Registry for Spine Surgery (NORspine) from 2007 to 2012. The primary outcome was change in Oswestry disability index (ODI) at 1 year. The secondary endpoint was perioperative complications. Complications were graded according to the Ibanez classification system.

RESULTS

For all patients (n = 125), the mean improvement in ODI at 1 year was 16.9 points (95% CI 13.5-20.2, p < 0.001). Seventy-six (71.7%) patients achieved a minimal clinically important difference in ODI (defined as ≥8 points improvement). The total number of complications within 3 months of surgery was 22 (17.6%). There were 14 medical and eight surgical complications, and all were Ibanez grade I or II (mild or moderate) complications. Four (3.2%) complications occurred while being admitted to the hospital and 18 (14.4%) occurred within 3 months following hospital discharge. The most common complication was urinary tract infection (n = 11, 8.8%).

CONCLUSIONS

Microsurgical decompression for central LSS in the absence of radiological instability is an effective and safe treatment.

Posterolateral Lumbar Arthrodesis With and Without Interbody Arthrodesis for L4-L5 Degenerative Spondylolisthesis: A Comparative Value Analysis

STUDY DESIGN

Independent retrospective review of prospectively collected data, comparative cohort study.

OBJECTIVE

The objective of this study was to compare the clinical, radiographical, and cost/value of the addition of an interbody arthrodesis (IBA) to a posterolateral arthrodesis (PLA) in the surgical treatment of L4-L5 degenerative spondylolisthesis (DS). The authors hypothesized that the addition of IBA to PLA would produce added value while incurring minimal additional costs.

SUMMARY OF BACKGROUND DATA

Many lumbar surgical advances have been made during the past several decades, yet there is a paucity of strong evidence-based validation, let alone comparative value analyses. The addition of an IBA to a PLA has become increasingly popular during the past 2 decades, yet the potential added value for the patient has not been carefully defined.

METHODS

Patients undergoing single-level arthrodesis for L4-L5 DS performed at our institution from 2004 to 2012 were identified. Exclusion criteria included multilevel arthrodesis, spinal stenosis requiring decompression at or above L2-L3, previous L4-L5 spinal fusion, spondylolisthesis of greater than 33% of the vertebral body, and use of minimally invasive surgery. Radiographical fusion status, epidemiological, surgical, and functional outcomes, and cost/value data were recorded or calculated.

RESULTS

A total of 179 patients with follow-up meeting inclusion criteria were identified: 68 with PLA alone and 111 with PLA + IBA. No statistical differences were noted in Oswestry Disability Index, 36-item Short-Form Health Survey scores, fusion rates, or cost/value at 6 months and at more than 3 years despite the PLA cohort being significantly older with more medical comorbidities. When length of stay was normalized across cohorts, the addition of an IBA increased hospital costs ranging from $577 to $5276, but this did not reach statistical significance.

CONCLUSION

This single-center review of open surgical treatment of L4-L5 DS demonstrated that the addition of IBA to PLA added cost while producing equivalent results in fusion rates, Oswestry Disability Index, and 36-item Short-Form Health Survey scores when compared with PLA alone.

LEVEL OF EVIDENCE

3.

Efficacy of epidural injections in the treatment of lumbar central spinal stenosis: a systematic review

Context:

Lumbar central spinal stenosis is common and often results in chronic persistent pain and disability, which can lead to multiple interventions. After the failure of conservative treatment, either surgical or nonsurgical modalities such as epidural injections are contemplated in the management of lumbar spinal stenosis.

Evidence Acquisition:

Recent randomized trials, systematic reviews and guidelines have reached varying conclusions about the efficacy of epidural injections in the management of central lumbar spinal stenosis. The aim of this systematic review was to determine the efficacy of all three anatomical epidural injection approaches (caudal, interlaminar, and transforaminal) in the treatment of lumbar central spinal stenosis. A systematic review was performed on randomized trials published from 1966 to July 2014 of all types of epidural injections used in the management of lumbar central spinal stenosis. Methodological quality assessment and grading of the evidence was performed.

Results:

The evidence in managing lumbar spinal stenosis is Level II for long-term improvement for caudal and lumbar interlaminar epidural injections. For transforaminal epidural injections, the evidence is Level III for short-term improvement only. The interlaminar approach appears to be superior to the caudal approach and the caudal approach appears to be superior to the transforaminal one.

Conclusions:

The available evidence suggests that epidural injections with local anesthetic alone or with local anesthetic with steroids offer short- and long-term relief of low back and lower extremity pain for patients with lumbar central spinal stenosis. However, the evidence is Level II for the long-term efficacy of caudal and interlaminar epidural injections, whereas it is Level III for short-term improvement only with transforaminal epidural injections.

An analysis of spinopelvic sagittal alignment after lumbar lordosis reconstruction for degenerative spinal diseases: how much balance can be obtained?

STUDY DESIGN

A retrospective and radiological study of degenerative spinal diseases.

OBJECTIVE

To explore the changes in spinopelvic sagittal alignment after lumbar instrumentation and fusion of degenerative spinal diseases.

SUMMARY OF BACKGROUND DATA

Efforts have been paid to clarify the ideal postoperative sagittal profile for degenerative spinal diseases. However, little has been published about the actual changes of sagittal alignment after lumbar lordosis reconstruction.

METHODS

Radiographical analysis of 83 patients with spinal degeneration was performed by measuring sagittal parameters before and after operations. Comparative studies of sagittal parameters between short (1 level) and long (≥ 2 level) instrumentation and fusion were performed. Different variances (Δ) of these sagittal parameters before and after operations were calculated and compared. Correlative study and linear regression were performed to establish the relationship between variances.

RESULTS

No significant changes were shown in the short-fusion group postoperatively. In the long-fusion group, postoperative lumbar lordosis (LL) and sacral slope (SS) were significantly increased; pelvic tilt (PT), sagittal vertical axis (SVA), pelvic incidence minus lumbar lordosis, and PT/SS were significantly decreased. Different variances of ΔLL, ΔSS, ΔPT, ΔSVA, Δ(pelvic incidence - LL), and ΔPT/SS were significantly greater in the long-fusion group than the short-fusion group. Close correlations were mainly shown among ΔLL, ΔPT, and ΔSVA. Linear regression equations could be developed (ΔPT = -0.185 × ΔLL - 7.299 and ΔSVA = -0.152ΔLL - 1.145).

CONCLUSION

In degenerative spinal diseases, long instrumentation and fusion (≥ 2 levels) provides more efficient LL reconstruction. PT, SS, and SVA improve corresponding to LL in a linear regression model. Linear regression equations could be developed and used to predict PT and SVA change after long instrumentation and fusion for LL reconstruction.

Predicting discharge placement and health care needs after lumbar spine laminectomy

OBJECTIVE

To explore factors associated with discharge placement (DP) and need for skilled assistance after patients are discharged from hospital following lumbar laminectomy.

METHODS

A retrospective analysis of 339 patients who underwent lumbar laminectomy was conducted. We used multivariable logistic regression analysis to identify significant covariates and to construct two regression models: a primary model to predict DP, home vs inpatient rehabilitation/skilled nursing facility (IR/SNF), and a secondary model to predict the need for skilled assistance once patients are discharged to home.

RESULTS

The sample included 48.7% females, 68.2% married, 56.3% independent in daily activities, and 85.2% discharged to home. Subjects were a mean 56.06 ± 12.75 years old and had a BMI of 31.35 ± 6.2. Of those discharged to home, 17.7% needed skilled assistance. Patients stayed 4.41 ± 3.55 days in the hospital and walked 203.38 ± 144.87 ft during hospital stay. Age, distance walked during hospital stay, and length of hospital stay (LOS) were significant positive predictors for discharge to home vs IR/SNF, whereas single living status, diminished prior level of function, and longer LOS were predictors of need for skilled assistance after discharge to home.

CONCLUSION

Age, mobility, marital status, prior level of function, and LOS are key variables in determining healthcare needs following lumbar laminectomy.

Body mass index and risk of surgical site infection following spine surgery: a meta-analysis

PURPOSE

Inconsistent results have been reported in the literature on the association between obesity, expressed as increased body mass index (BMI), and risk for surgical site infection (SSI) following spine surgery. The objective of this study was to review and quantify the association between increased BMI and risk of spinal SSI in adults.

METHODS

We performed a comprehensive search for relevant studies using PubMed, Embase, and references of published manuscripts. Study-specific risk measures were transformed into slope estimates and combined using the random effects meta-analysis model to establish the risk of SSI associated with every 5-unit increase in BMI.

RESULTS

Thirty-four articles underwent full-text review. Variations were noted among these studies in relation to SSI diagnosis criteria and BMI cut-off levels used to define obesity. Data from 12 retrospective studies were included in the analyses. Results showed that BMI was significantly positively associated with the risk of spinal SSI. Unadjusted risk estimates demonstrated that a 5-unit increase in BMI was associated with 13 % increased risk of SSI [Crude odds ratio (OR): 1.13; 95 % CI: 1.07-1.19, p < 0.0001]. Pooling of risk estimates adjusted for diabetes and other confounders resulted in a 21 % increase in risk of spinal SSI for every 5-unit increase in BMI (adjusted OR: 1.21; 95 % CI 1.13-1.29, p < 0.0001).

CONCLUSION

Higher BMI is associated with the increased risk of SSI following spine surgery. Prospective studies are needed to confirm this association and to determine whether other measures of fat distribution are better predictors of risk of SSI.