Evidence and practice in spine registries

Expectations in patients undergoing spine surgery are high and unmet

BACKGROUND CONTEXT

Defining success in spine surgery lacks a standardized approach, and all existing concepts are based on registrations after surgery.

PURPOSE

To examine patients' expectations before spine surgery assessed by a modified Oswestry Disability Index (ODI) and Numeric Rating Scale (NRS). The authors asked: how do the expectations align with actual outcomes and can a patient's individual expectations be used as a success criterion in itself?

STUDY DESIGN /SETTING

Prospective single-center study.

PATIENT SAMPLE

Patients scheduled for spine surgery at Akershus University Hospital (AHUS) were included in the study. They underwent 1 of 3 procedures: decompression for spinal stenosis, disc removal for lumbar disc herniation, or spinal fusion for degenerative disc disease.

OUTCOME MEASURES

Modified and standard version of ODI and NRS (back and leg pain).

METHODS

Preoperatively, the patients were given a modified ODI and NRS questionnaire in which they were asked to register the minimum acceptable functional impairment and pain they anticipated to have postsurgery. The patients' expectations were compared with 3-and 12-month follow-up data from the Norwegian Registry for Spine Surgery (NORspine) with ODI, NRS and Global Perceived Effect (GPE) scale. We used simple descriptive statistics.

RESULTS

A total of 93 patients completed the pre-op questionnaire. Of these, 65 responded to the 3-month follow-up and 53 at 12-month follow-up. The mean (95%CI) ODI before surgery was 38.3 (34.2-42.3), the mean (95% CI) preoperative NRS back pain was 6.34 (5.81-6.88), and leg pain was 6.67 (6.08-7.26). The patients expected a mean (95% CI) ODI of 10.5 (7.5-13.5), mean (95%CI) NRS back pain of 2.5 (2.1-3.0), and NRS leg pain of 1.8 (1.5-2.2). The actual clinical outcome after 12 months were a mean (95% CI) ODI of 21.7 (17.0-26.5), NRS back pain of 3.4 (2.8-4.1), and leg pain of 2.8 (2.0-3.5). Only 12 (30.8%) patients achieved their expected ODI, while 26 (65.0%) classified themselves as significantly better according to GPE.

CONCLUSIONS

Patients seem to have high expectations before spine surgery, and the expectations may exceed the clinical outcome. Only 30.8% had their ODI expectations met, but perceived benefit was higher. High expectations may be due to inadequate preoperative information and/or the unsuitability of ODI for capturing expectations.

Physical functioning in the lumbar spinal surgery population: A systematic review and narrative synthesis of outcome measures and measurement properties of the physical measures

BACKGROUND

International agreement supports physical functioning as a key domain to measure interventions effectiveness for low back pain. Patient reported outcome measures (PROMs) are commonly used in the lumbar spinal surgery population but physical functioning is multidimensional and necessitates evaluation also with physical measures.

OBJECTIVE

1) To identify outcome measures (PROMs and physical) used to evaluate physical functioning in the lumbar spinal surgery population. 2) To assess measurement properties and describe the feasibility and interpretability of physical measures of physical functioning in this population.

STUDY DESIGN

Two-staged systematic review and narrative synthesis.

METHODS

This systematic review was conducted according to a registered and published protocol. Two stages of searching were conducted in MEDLINE, EMBASE, Health & Psychosocial Instruments, CINAHL, Web of Science, PEDro and ProQuest Dissertations & Theses. Stage one included studies to identify physical functioning outcome measures (PROMs and physical) in the lumbar spinal surgery population. Stage two (inception to 10 July 2023) included studies assessing measurement properties of stage one physical measures. Two independent reviewers determined study eligibility, extracted data and assessed risk of bias (RoB) according to COSMIN guidelines. Measurement properties were rated according to COSMIN criteria. Level of evidence was determined using a modified GRADE approach.

RESULTS

Stage one included 1,101 reports using PROMs (n = 70 established in literature, n = 67 developed by study authors) and physical measures (n = 134). Stage two included 43 articles assessing measurement properties of 34 physical measures. Moderate-level evidence supported sufficient responsiveness of 1-minute stair climb and 50-foot walk tests, insufficient responsiveness of 5-minute walk and sufficient reliability of distance walked during the 6-minute walk. Very low/low-level evidence limits further understanding.

CONCLUSIONS

Many physical measures of physical functioning are used in lumbar spinal surgery populations. Few have investigations of measurement properties. Strongest evidence supports responsiveness of 1-minute stair climb and 50-foot walk tests and reliability of distance walked during the 6-minute walk. Further recommendations cannot be made because of very low/low-level evidence. Results highlight promise for a range of measures, but prospective, low RoB studies are required.

Improvements in Quality, Safety and Costs Associated with Use of Implant Registries Within a Health System

BACKGROUND

Clinical quality registries (CQRs) are intended to enhance quality, safety, and cost reduction using real-world data for a self-improving health system. Starting in 2001, Kaiser Permanente established several medical device CQRs as a quality improvement initiative. This report examines the contributions of these CQRs on improvement in health outcomes, changes in clinical practice, and cost-effectiveness over the past 20 years.

METHODS

Eight implant registries were instituted with standardized collection from the electronic health record and other institutional data sources of patient characteristics, medical comorbidities, implant attributes, procedure details, surgical techniques, and outcomes (including complications, revisions, reoperations, hospital readmissions, and other utilization measures). A rigorous quality control system is in place to improve and maintain the quality of data. Data from the Implant Registries form the basis for multiple quality improvement and patient safety initiatives to minimize variation in care, promote clinical best practices, facilitate recalls, perform benchmarking, identify patients at risk, and construct reports about individual surgeons.

RESULTS

Following the inception of the Implant Registries, there was an observed (1) reduction in opioid utilization following orthopedic procedures, (2) reduction in use of bone morphogenic protein during lumbar fusion allowing for cost savings, (3) reduction in allograft for anterior cruciate ligament reconstruction and subsequent decrease in organizationwide revision rates, (4) cost savings through expansion of same-day discharge programs for joint arthroplasty, (5) increase in the use of cement fixation in the hemiarthroplasty treatment of hip fracture, and (6) organizationwide discontinuation of an endograft device associated with a higher risk for adverse outcomes following endovascular aortic aneurysm repair.

CONCLUSION

The use of Implant Registries within our health system, along with clinical leadership and organizational commitment to a learning health system, was associated with improved quality and safety outcomes and reduced costs. The exact mechanisms by which such registries affect health outcomes and costs require further study.

Postoperative complications after surgery for lumbar spinal stenosis, assessment using two different data sources

PURPOSE

Lumbar spinal stenosis (LSS) is a prevalent disorder, and surgery for LSS is a common procedure. Postoperative complications occur after any surgery and impose costs for society and costs and additional morbidity for patients. Since complications are relatively rare, medical registries of large populations may provide valuable knowledge. However, recording of complications in registries can be incomplete. To better estimate the true prevalence of complications after LSS surgery, we reviewed two different sources of data and recorded complications for a sample of Norwegian LSS patients.

METHODS

474 patients treated surgically for LSS during 2015 and 2016 at four hospitals reported to a national spine registry (NORspine). Postoperative complications were recorded by patients in NORspine, and we cross-referenced complications documented in NORspine with the patients´ electronic patient records (EPR) to re-test the complication rates. We performed descriptive statistics of complication rates using the two different data sources above, and analyzed the association between postoperative complications and clinical outcome with logistic regression.

RESULTS

The mean (95%CI) patient age was 66.3 (65.3-67.2) years, and 254 (53.6%) were females. All patients were treated with decompression, and 51 (10.7%) received an additional fusion during the index surgery. Combining the two data sources, we found a total rate for postoperative complications of 22.4%, the NORspine registry reported a complication rate of 15.6%, and the EPR review resulted in a complication rate of 16.0%. However, the types of complications were inconsistent across the two data sources. According to NORspine, the frequency of reoperation within 90 days was 0.9% and according to EPR 3.4%. The rates of wound infection were for NORspine 3.1% and EPR review 2.1%. There was no association between postoperative complication and patient reported outcome.

CONCLUSION

Postoperative complications occurred in 22% of LSS patients. The frequency of different postoperative complications differed between the two data sources.

Long-term comparison of anterior (ALIF) versus transforaminal (TLIF) lumbar interbody fusion: a propensity score-matched register-based study

PURPOSE

Anterior (ALIF) and transforaminal (TLIF) lumbar interbody fusion have shown similar clinical outcomes at short- and medium-term follow-ups. Possible advantages of ALIF in the long run could be better disc height and lumbar lordosis and reduced risk of adjacent segment disease. We aimed to study if ALIF could be associated with superior clinical outcomes than TLIF at long-term follow-up.

METHODS

We analysed 535 patients treated with ALIF or TLIF of the L5-S1 spinal segment between 2007 and 2017 who completed long-term follow-up in a national spine registry database (NORspine). We defined treatment success after surgery as at least 30% improvement in Oswestry Disability Index (ODI) at long-term follow-up. Patients treated with ALIF and TLIF and who responded at long term were balanced by propensity score matching. The proportions of successfully treated patients within each group were compared by numbers and percentages with corresponding relative risk.

RESULTS

The mean (95%CI) age of the total study population was 50 (49-51) years, and 264 (49%) were females. The mean (95%CI) preoperative ODI score was 40 (39-42), and 174 (33%) had previous spine surgery. Propensity score matching left 120 patients in each treatment group. At a median (95%CI) of 92 (88-97) months after surgery, we found no difference in proportions successfully treated patients with ALIF versus TLIF (68 (58%) versus 77 (65%), RR (95%CI) = 0.88 (0.72 to1.08); p = 0.237).

CONCLUSIONS

This propensity score-matched national spine register study of patients treated with ALIF versus TLIF of the lumbosacral junction found no differences in proportions of successfully treated patients at long-term follow-up.

LEVEL OF EVIDENCE I

Diagnostic: individual cross-sectional studies with the consistently applied reference standard and blinding.

Machine Learning Models for Predicting Disability and Pain Following Lumbar Disc Herniation Surgery

Importance

Lumber disc herniation surgery can reduce pain and disability. However, a sizable minority of individuals experience minimal benefit, necessitating the development of accurate prediction models.

Objective

To develop and validate prediction models for disability and pain 12 months after lumbar disc herniation surgery.

Design, Setting, and Participants

A prospective, multicenter, registry-based prognostic study was conducted on a cohort of individuals undergoing lumbar disc herniation surgery from January 1, 2007, to May 31, 2021. Patients in the Norwegian Registry for Spine Surgery from all public and private hospitals in Norway performing spine surgery were included. Data analysis was performed from January to June 2023.

Exposures

Microdiscectomy or open discectomy.

Main Outcomes and Measures

Treatment success at 12 months, defined as improvement in Oswestry Disability Index (ODI) of 22 points or more; Numeric Rating Scale (NRS) back pain improvement of 2 or more points, and NRS leg pain improvement of 4 or more points. Machine learning models were trained for model development and internal-external cross-validation applied over geographic regions to validate the models. Model performance was assessed through discrimination (C statistic) and calibration (slope and intercept).

Results

Analysis included 22 707 surgical cases (21 161 patients) (ODI model) (mean [SD] age, 47.0 [14.0] years; 12 952 [57.0%] males). Treatment nonsuccess was experienced by 33% (ODI), 27% (NRS back pain), and 31% (NRS leg pain) of the patients. In internal-external cross-validation, the selected machine learning models showed consistent discrimination and calibration across all 5 regions. The C statistic ranged from 0.81 to 0.84 (pooled random-effects meta-analysis estimate, 0.82; 95% CI, 0.81-0.84) for the ODI model. Calibration slopes (point estimates, 0.94-1.03; pooled estimate, 0.99; 95% CI, 0.93-1.06) and calibration intercepts (point estimates, -0.05 to 0.11; pooled estimate, 0.01; 95% CI, -0.07 to 0.10) were also consistent across regions. For NRS back pain, the C statistic ranged from 0.75 to 0.80 (pooled estimate, 0.77; 95% CI, 0.75-0.79); for NRS leg pain, the C statistic ranged from 0.74 to 0.77 (pooled estimate, 0.75; 95% CI, 0.74-0.76). Only minor heterogeneity was found in calibration slopes and intercepts.

Conclusion

The findings of this study suggest that the models developed can inform patients and clinicians about individual prognosis and aid in surgical decision-making.

Factors Predicting Clinically Relevant Pain Relief After Spinal Cord Stimulation for Patients With Chronic Low Back and/or Leg Pain: A Systematic Review With Meta-Analysis and Meta-Regression

RATIONALE

To optimize results with spinal cord stimulation (SCS) for chronic low back pain (CLBP) and/or leg pain, including persistent spinal pain syndrome (PSPS), careful patient selection based on proved predictive factors is essential. Unfortunately, the necessary selection process required to optimize outcomes of SCS remains challenging.

OBJECTIVE

This review aimed to evaluate predictive factors of clinically relevant pain relief after SCS for patients with CLBP and/or radicular leg pain, including PSPS.

MATERIALS AND METHODS

In August 2023, PubMed, Cinahl, Cochrane, and EMBASE were searched to identify studies published between January 2010 and August 2023. Studies reporting the percentage of patients with ≥50% pain relief after SCS in patients with CLBP and leg pain, including PSPS at 12 or 24 months, were included. Meta-analysis was conducted to pool results for back, leg, and general pain relief. Predictive factors for pain relief after 12 months were examined using univariable and multivariable meta-regression.

RESULTS

A total of 27 studies (2220 patients) were included for further analysis. The mean percentages of patients with substantial pain relief were 68% for leg pain, 63% for back pain, and 73% for general pain at 12 months follow-up, and 63% for leg pain, 59% for back pain, and 71% for general pain at 24 months follow-up assessment. The implantation method and baseline Oswestry Disability Index made the multivariable meta-regression model for ≥50% back pain relief. Sex and pain duration made the final model for ≥50% leg pain relief. Variable stimulation and implantation method made the final model for general pain relief.

CONCLUSIONS

This review supports SCS as an effective pain-relieving treatment for CLBP and/or leg pain, and models were developed to predict substantial back and leg pain relief. To provide high-grade evidence for predictive factors, SCS studies of high quality are needed in which standardized factors predictive of SCS success, based on in-patient improvements, are monitored and reported.

The Norwegian registry for spine surgery (NORspine): cohort profile

PURPOSE

To review and describe the development, methods and cohort of the lumbosacral part of the Norwegian registry for spine surgery (NORspine).

METHODS

NORspine was established in 2007. It is government funded, covers all providers and captures consecutive cases undergoing operations for degenerative disorders. Patients' participation is voluntary and requires informed consent. A set of baseline-, process- and outcome-variables (3 and 12 months) recommended by the International Consortium for Health Outcome Measurement is reported by surgeons and patients. The main outcome is the Oswestry disability index (ODI) at 12 months.

RESULTS

We show satisfactory data quality assessed by completeness, timeliness, accuracy, relevance and comparability. The coverage rate has been 100% since 2016 and the capture rate has increased to 74% in 2021. The cohort consists of 60,647 (47.6% women) cases with mean age 55.7 years, registered during the years 2007 through 2021. The proportions > 70 years and with an American Society of Anaesthesiologists' Physical Classification System (ASA) score > II has increased gradually to 26.1% and 19.3%, respectively. Mean ODI at baseline was 43.0 (standard deviation 17.3). Most cases were operated with decompression for disc herniation (n = 26,557, 43.8%) or spinal stenosis (n = 26,545, 43.8%), and 7417 (12.2%) with additional or primary fusion. The response rate at 12 months follow-up was 71.6%.

CONCLUSION

NORspine is a well-designed population-based comprehensive national clinical quality registry. The register's methods ensure appropriate data for quality surveillance and improvement, and research.

National spine surgery registries' characteristics and aims: globally accepted standards have yet to be met. Results of a scoping review and a complementary survey

BACKGROUND

Surgery involving implantable devices is widely used to solve several health issues. National registries are essential tools for implantable device surveillance and vigilance. In 2017, the European Union encouraged Member States to establish "registries and databanks for specific types of devices" to evaluate device safety and performance and ensure their traceability. Spine-implantable devices significantly impact patient safety and public health; spine registries might help improve surgical outcomes. This study aimed to map existing national spine surgery registries and highlight their features and organisational standards to provide an essential reference for establishing other national registries.

METHODS

A scoping search was performed using the Embase, PubMed/Medline, Scopus, and Web of Science databases for the terms "registry", "register", "implantable", and all terms and synonyms related to spinal diseases and national registries in publications from January 2000 to December 2020. This search was later updated and finalised through a web search and an ad hoc survey to collect further detailed information.

RESULTS

Sixty-two peer-reviewed articles were included, which were related to seven national spine registries, six of which were currently active. Three additional active national registries were found through the web search. The nine selected national registries were set up between 1998 and 2021. They collect data on the procedure and use patient-reported outcome measures (PROMs) for the follow-up.

CONCLUSION

Our study identified nine currently active national spine surgery registries. However, globally accepted standards for developing a national registry of spine surgery are yet to be established. Therefore, an international effort to increase result comparability across registries is highly advisable. We hope the recent initiative from the Orthopaedic Data Evaluation Panel (ODEP) to establish an international collaboration will meet these needs.

Initial learning curve after switching to uniportal endoscopic discectomy for lumbar disc herniations

PURPOSE

The purpose was to investigate the learning curve for elective endoscopic discectomy performed by a single surgeon who made a complete switch to uniportal endoscopic surgery for lumbar disc herniations in an ambulatory surgery center and determine the minimum case number required to safely overcome the initial learning curve.

METHODS

Electronic medical records (EMR) of the first 90 patients receiving endoscopic discectomy by the senior author in an ambulatory surgery center were reviewed. Cases were divided by approach, transforaminal (46) versus interlaminar (44). Patient-reported outcome measures (visual-analog-score (VAS) and the Oswestry disability index (ODI)) were recorded preoperatively and at 2-week, 6-week, 3-month, and 6-month appointments. Operative times, complications, time to discharge from PACU, postoperative narcotic use, return to work, and reoperations were compiled.

RESULTS

Median operative time decreased approximately 50% for the first 50 patients then plateaued for both approaches (mean: 65 min). No difference in reoperation rate observed during the learning curve. Mean time to reoperation was 10 weeks, with 7(7.8%) reoperations. The interlaminar and transforaminal median operative times were 52 versus 73 min, respectively (p = 0.03). Median time to discharge from PACU was 80 min for interlaminar approaches and 60 min for transforaminal (p < 0.001). Mean VAS and ODI scores 6 weeks and 6 months postoperatively were statistically and clinically improved from preoperatively. The duration of postoperative narcotic use and narcotics need significantly decreased during the learning curve as the senior author realized that narcotics were not needed. No differences were apparent between groups in other metrics.

CONCLUSIONS

Endoscopic discectomy was shown to be safe and effective for symptomatic disc herniations in an ambulatory setting. Median operative time decreases by half over the first 50 patients in our learning curve, while reoperation rates remained similar without the need for hospital transfer or conversion to an open procedure in an ambulatory setting.

LEVEL OF EVIDENCE

Level III, prospective cohort.

Characteristics and outcomes of patients who did not respond to a national spine surgery registry

BACKGROUND

Loss to follow-up may bias outcome assessments in medical registries. This cohort study aimed to analyze and compare patients who failed to respond with those that responded to the Norwegian Registry for Spine Surgery (NORspine).

METHODS

We analyzed a cohort of 474 consecutive patients operated for lumbar spinal stenosis at four public hospitals in Norway during a two-year period. These patients reported sociodemographic data, preoperative symptoms, and Oswestry Disability Index (ODI), numerical rating scales (NRS) for back and leg pain to NORspine at baseline and 12 months postoperatively. We contacted all patients who did not respond to NORspine after 12 months. Those who responded were termed responsive non-respondents and compared to 12 months respondents.

RESULTS

One hundred forty (30%) did not respond to NORspine 12 months after surgery and 123 were available for additional follow-up. Sixty-four of the 123 non-respondents (52%) responded to a cross-sectional survey done at a median of 50 (36-64) months after surgery. At baseline, non-respondents were younger 63 (SD 11.7) vs. 68 (SD 9.9) years (mean difference (95% CI) 4.7 years (2.6 to 6.7); p =  < 0.001) and more frequently smokers 41 (30%) vs. 70 (21%) RR (95%CI) = 1.40 (1.01 to 1.95); p = 0.044. There were no other relevant differences in other sociodemographic variables or preoperative symptoms. We found no differences in the effect of surgery on non-respondents vs. respondents (ODI (SD) = 28.2 (19.9) vs. 25.2 (18.9), MD (95%CI) = 3.0 ( -2.1 to 8.1); p = 0.250).

CONCLUSION

We found that 30% of patients did not respond to NORspine at 12 months after spine surgery. Non-respondents were somewhat younger and smoked more frequently than respondents; however, there were no differences in patient-reported outcome measures. Our findings suggest that attrition bias in NORspine was random and due to non-modifiable factors.

Comorbidity data collection across different spine registries: an evidence map

INTRODUCTION

Comorbidities are significant patient factors that contribute to outcomes after surgery. There is highly variable collection of this information across the literature. To help guide the systematic collection of best practice data, the Australian Spine Registry conducted an evidence map to investigate (i) what comorbidities are collected by spine registries, (ii) how they are collected and (iii) the compliance and completeness in collecting comorbidity data.

METHOD

A literature search was performed to identify published studies of adult spine registry data reporting comorbidities. In addition, targeted questionnaires were sent to existing global spine registries to identify the maximum number of relevant results to build the evidence map.

RESULTS

Thirty-six full-text studies met the inclusion criteria. There was substantial variation in the reporting of comorbidity data; 55% of studies reported comorbidity collection, but only 25% reported the data collection method and 20% reported use of a comorbidity index. The variation in the literature was confirmed with responses from 50% of the invited registries (7/14). Of seven, three use a recognised comorbidity index and the extent and methods of comorbidity collection varied by registry.

CONCLUSION

This evidence map identified variations in the methodology, data points and reporting of comorbidity collection in studies using spine registry data, with no consistent approach. A standardised set of comorbidities and data collection methods would encourage collaboration and data comparisons between patient cohorts and could facilitate improved patient outcomes following spine surgery by allowing data comparisons and predictive modelling of risk factors.

Current status and future prospects of the Japanese orthopaedic association national registry (JOANR), Japan's first national registry of orthopaedic surgery

The Japanese Orthopaedic Association National Registry (JOANR) is Japan's first national registry of orthopaedic surgery, which has been developed after having been selected for the Project for Developing a Database of Clinical Outcome approved by the Health Policy Bureau of the Ministry of Health, Labour and Welfare. Its architecture has two levels of registration, one being the basic items of surgical procedure, disease, information on surgeons, surgery-related information, and outcome, and the other being detailed items in the affiliated registries of partner medical associations. It has a number of features, including the facts that, because it handles medical data, which constitute special care-required personal information, data processing is conducted entirely in a cloud environment with the imposition of high-level data security measures; registration of the implant data required to assess implant performance has been automated via a bar code reader app; and the system structure enables flexible collaboration with the registries of partner associations. JOANR registration is a requirement for accreditation as a core institution or partner institution under the board certification system, and the total number of cases registered during the first year of operation (2020) was 899,421 registered by 2,247 institutions, providing real-world evidence concerning orthopaedic surgery.

Predictors for failure after surgery for lumbar spinal stenosis: a prospective observational study

BACKGROUND/CONTEXT

Some patients do not improve after surgery for lumbar spinal stenosis (LSS), and surgical treatment implies a risk for complications and deterioration. Patient selection is of paramount importance to improve the overall clinical results and identifying predictive factors for failure is central in this work.

PURPOSE

We aimed to explore predictive factors for failure and worsening after surgery for LSS.

STUDY DESIGN /SETTING

Retrospective observational study on prospectively collected data from a national spine registry with a 12-month follow-up.

PATIENT SAMPLE

We analyzed 11,873 patients operated for LSS between 2007 and 2017 in Norway, included in the Norwegian registry for spine surgery (NORspine). Twelve months after surgery, 8919 (75.1%) had responded.

OUTCOME MEASURES

Oswestry Disability Index (ODI) 12 months after surgery.

METHODS

Predictors were assessed with uni- and multivariate logistic regression, using backward conditional stepwise selection and a significance level of 0.01. Failure (ODI>31) and worsening (ODI>39) were used as dependent variables.

RESULTS

Mean (95%CI) age was 66.6 (66.4-66.9) years, and 52.1% were females. The mean (95%CI) preoperative ODI score was 39.8 (39.4-40.1). All patients had decompression, and 1494 (12.6%) had an additional fusion procedure. Twelve months after surgery, the mean (95%CI) ODI score was 23.9 (23.5-24.2), and 2950 patients (33.2%) were classified as failures and 1921 (21.6%) as worse. The strongest predictors for failure were duration of back pain > 12 months (OR [95%CI]=2.24 [1.93-2.60]; p<.001), former spinal surgery (OR [95%CI]=2.21 [1.94-2.52]; p<.001) and age>70 years (OR (95%CI)=1.97 (1.69-2.30); p<.001). Socioeconomic variables increased the odds of failure (ORs between 1.36 and 1.62). The strongest predictors for worsening were former spinal surgery (OR [95%CI]=2.04 [1.77-2.36]; p<.001), duration of back pain >12 months (OR [95%CI]=1.83 [1.45-2.32]; p<.001) and age >70 years (OR [95%CI]=1.79 [1.49-2.14]; p<.001). Socioeconomic variables increased the odds of worsening (ORs between 1.33-1.67).

CONCLUSIONS

After surgery for LSS, 33% of the patients reported failure, and 22% reported worsening as assessed by ODI. Preoperative duration of back pain for longer than 12 months, former spinal surgery, and age above 70 years were the strongest predictors for increased odds of failure and worsening after surgery.

Non-respondents do not bias outcome assessment after cervical spine surgery: a multicenter observational study from the Norwegian registry for spine surgery (NORspine)

BACKGROUND

The Norwegian registry for spine surgery (NORspine) is a national clinical quality registry which has recorded more than 10,000 operations for degenerative conditions of the cervical spine since 2012. Registries are large observational cohorts, at risk for attrition bias. We therefore aimed to examine whether clinical outcomes differed between respondents and non-respondents to standardized questionnaire-based 12-month follow-up.

METHODS

All eight public and private providers of cervical spine surgery in Norway report to NORspine. We included 334 consecutive patients who were registered with surgical treatment of degenerative conditions in the cervical spine in 2018 and did a retrospective analysis of prospectively collected register data and data on non-respondents' outcomes collected by telephone interviews. The primary outcome measure was patient-reported change in arm pain assessed with the numeric rating scale (NRS). Secondary outcome measures were change in neck pain assessed with the NRS, change in health-related quality of life assessed with EuroQol 5 Dimensions (EQ-5D), and patients' perceived benefit of the operation assessed by the Global Perceived Effect (GPE) scale.

RESULTS

At baseline, there were few and small differences between the 238 (71.3%) respondents and the 96 (28.7%) non-respondents. We reached 76 (79.2%) non-respondents by telephone, and 63 (65.6%) consented to an interview. There was no statistically significant difference between groups in change in NRS score for arm pain (3.26 (95% CI 2.84 to 3.69) points for respondents and 2.77 (1.92 to 3.63) points for telephone interviewees) or any of the secondary outcome measures.

CONCLUSIONS

The results indicate that patients lost to follow-up were missing at random. Analyses of outcomes based on data from respondents can be considered representative for the complete register cohort, if patient characteristics associated with attrition are controlled for.

Outcomes After Lumbar Disk Herniation Surgery in the Dutch Population

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

There is only limited data on the outcome of primary surgery of lumbar disk herniation (LDH) in Dutch patients. The objective of this study is to describe undesirable outcomes after primary LDH.

METHODS

The National Claims Database (Vektis) was searched for primary LDH operations performed from July 2015 until June 2016, for reoperations within 18 months, prescription of opioids between 6 to 12 months and nerve root block within 1 year. A combined outcome measure was also made. Group comparisons were analyzed with the Student's t-test.

RESULTS

Primary LDH surgery was performed in 6895 patients in 70 hospitals. Weighted mean of reoperations was 7.3%, nerve root block 6.7% and opioid use 15.6%. In total, 23.0% of patients had one or more undesirable outcomes after surgery. The 95% CI interval exceeded the 50% incidence line for 14 out of 26 hospitals with less than 50 surgical interventions per year. Although the data suggested a volume effect on undesired outcomes, the t-tests between hospitals with volume thresholds of 100, 150 and 200 interventions per year did not support this (P values 0.078, 0.129, 0.114).

CONCLUSION

This unique nationwide claims-based study provides insight into patient-relevant undesirable outcomes such as reoperation, nerve root block and opioid use after LDH surgery. About a quarter of the patients had a serious complication in the first follow up year that prompted further medical treatment. There is a wide variation in complication rates between hospitals with a trend that supports concentration of LDH care.

Standard set of network outcomes for traumatic spinal cord injury: a consensus-based approach using the Delphi method

STUDY DESIGN

Consensus study.

OBJECTIVES

The purpose of this study is to define a standardized (network) outcomes set for traumatic spinal cord injury (t-SCI), covering the patient journey from acute to chronic rehabilitation phase, including patient-relevant outcomes, adequate measurement instruments, as well as case-mix and risk factors.

SETTING

Acute Spinal Cord Injury (ASCI) Unit Nijmegen, the Netherlands.

METHODS

A modified Delphi method was performed, including a multidisciplinary panel of 19 health-care professionals with experience in t-SCI management. Formal consensus was reached after two web-based surveys, a face-to-face meeting, and a final confirmation round (threshold consensus: 70%).

RESULTS

In the first two Delphi rounds, 18/19 invited panelists (94.7%) responded and 10 panelists participated in the final meeting. The prefinal set was confirmed by all panelists. The standard set encompasses the three-tiered outcome hierarchy and consists of patient-reported and clinician-reported outcome domains and measurement instruments. Consensus was reached to include survival, degree of health or recovery, time to recovery, and return to normal activities, disutility of care or treatment process, sustainability of health and nature of recurrences, and long-term consequences of therapy. A measurement schedule was defined as well as for proposed casemix and risk factors, including demographics, clinical status, and treatment process.

CONCLUSION

A standard set of network outcomes is developed that could be implemented in hospitals and rehabilitation centers involved in the treatment of t-SCI. Using this standard set, comparison of the quality of care is possible and prognostic prediction of outcomes of treatment is feasible, so that each patient receives the right care at the right time in the right place.

Physical functioning outcome measures in the lumbar spinal surgery population and measurement properties of the physical outcome measures: protocol for a systematic review

INTRODUCTION

Low back pain can lead to substantial decline in physical functioning. For disabling pain not responsive to conservative management, surgical intervention can enhance physical functioning. Measurements of physical functioning include patient-reported outcome measures and physical outcome measures using evaluations of impairments, performance on a standardised task or activity in a natural environment. Selecting outcome measures with adequate measurement properties is fundamental to evaluating effectiveness of interventions. The purpose of this systematic review is to identify outcome measures (patient reported and physical) used to evaluate physical functioning (stage 1) and assess the measurement properties of physical outcome measures of physical functioning (stage 2) in the lumbar spinal surgery population.

METHODS AND ANALYSIS

This protocol aligns with the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) guidelines and Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols. Using a two-staged approach, searches will be performed in MEDLINE, EMBASE, Health and Psychosocial Instruments, CINAHL, Web of Science, Scopus, PEDro and the grey literature from inception until 15 December 2021. Stage 1 will identify studies evaluating physical functioning with patient-reported or physical outcome measures in the lumbar spinal surgery population. Stage 2 will search for studies evaluating measurement properties (validity, reliability, responsiveness) of the physical outcome measures identified in stage 1 in the lumbar spinal surgery population. Two independent reviewers will evaluate studies for inclusion, extract data, assess risk of bias (COSMIN risk of bias tool and checklist) and quality of evidence (modified Grading of Recommendations Assessment, Development and Evaluation approach). Results for each measurement property per physical outcome measure will be quantitatively pooled if there is adequate clinical and methodological homogeneity or qualitatively synthesised if there is high heterogeneity in studies.

ETHICS AND DISSEMINATION

Ethics approval is not required. Results will be disseminated through peer-reviewed journal publication and conference presentation.

PROSPERO REGISTRATION NUMBER

CRD42021293880.

Clinical improvement after surgery for degenerative cervical myelopathy; A comparison of Patient-Reported Outcome Measures during 12-month follow-up

OBJECT

Although many patients report clinical improvement after surgery due to degenerative cervical myelopathy, the aim of intervention is to stop progression of spinal cord dysfunction. We wanted to provide estimates and assess achievement rates of Minimal Clinically Important Difference (MCID) at 3- and 12-month follow-up for Neck Disability Index (NDI), Numeric Rating Scale for arm pain (NRS-AP) and neck pain (NRS-NP), Euro-Qol (EQ-5D-3L), and European Myelopathy Score (EMS).

METHODS

614 degenerative cervical myelopathy patients undergoing surgery responded to Patient-Reported Outcome Measures (PROMs) prior to, 3 and 12 months after surgery. External criterion was the Global Perceived Effect Scale (1-7), defining MCID as "slightly better", "much better" and "completely recovered". MCID estimates with highest sensitivity and specificity were calculated by Receiver Operating Curves for change and percentage change scores in the whole sample and in anterior and posterior procedural groups.

RESULTS

The NDI and NRS-NP percentage change scores were the most accurate PROMs with a MCID of 16%. The change score for NDI and percentage change scores for NDI, NRS-AP and NRS-NP were slightly higher in the anterior procedure group compared to the posterior procedure group, while remaining PROM estimates were similar across procedure type. The MCID achievement rates at 12-month follow-up ranged from 51% in EMS to 62% in NRS-NP.

CONCLUSION

The NDI and NRS-NP percentage change scores were the most accurate PROMs to measure clinical improvement after surgery for degenerative cervical myelopathy. We recommend using different cut-off estimates for anterior and posterior approach procedures. A MCID achievement rate of 60% or less must be interpreted in the perspective that the main goal of surgery for degenerative cervical myelopathy is to prevent worsening of the condition.

Relevant impact of surgery on quality of life for adolescent idiopathic scoliosis : a registry-based two-year follow-up cohort study

AIMS

To determine the value of scoliosis surgery, it is necessary to evaluate outcomes in domains that matter to patients. Since randomized trials on adolescent idiopathic scoliosis (AIS) are scarce, prospective cohort studies with comparable outcome measures are important. To enhance comparison, a core set of patient-related outcome measures is available. The aim of this study was to evaluate the outcomes of AIS fusion surgery at two-year follow-up using the core outcomes set.

METHODS

AIS patients were systematically enrolled in an institutional registry. In all, 144 AIS patients aged ≤ 25 years undergoing primary surgery (median age 15 years (interquartile range 14 to 17) were included. Patient-reported (condition-specific and health-related quality of life (QoL); functional status; back and leg pain intensity) and clinician-reported outcomes (complications, revision surgery) were recorded. Changes in patient-reported outcome measures (PROMs) were analyzed using Friedman's analysis of variance. Clinical relevancy was determined using minimally important changes (Scoliosis Research Society (SRS)-22r), cut-off values for relevant effect on functioning (pain scores) and a patient-acceptable symptom state (PASS; Oswestry Disability Index).

RESULTS

At baseline, 65 out of 144 patients (45%) reported numerical rating scale (NRS) back pain scores > 5. All PROMs significantly improved at two-year follow-up. Mean improvements in SRS-22r function (+ 1.2 (SD 0.6)), pain (+ 0.6 (SD 0.8)), and self-image (+ 1.1 (SD 0.7)) domain scores, and the SRS-22r total score (+ 0.5 (SD 0.5)), were clinically relevant. At two-year follow-up, 14 out of 144 patients (10%) reported NRS back pain > 5. Surgical site infections did not occur. Only one patient (0.7%) underwent revision surgery.

CONCLUSION

Relevant improvement in functioning, condition-specific and health-related QoL, self-image, and a relevant decrease in pain is shown at two-year follow-up after fusion surgery for AIS, with few adverse events. Contrary to the general perception that AIS is a largely asymptomatic condition, nearly half of patients report significant preoperative back pain, which reduced to 10% at two-year follow-up. Cite this article: Bone Joint J 2022;104-B(2):265-273.

Criteria for failure and worsening after surgery for lumbar spinal stenosis: a prospective national spine registry observational study

BACKGROUND CONTEXT

Criteria for success after surgical treatment of lumbar spinal stenosis (LSS) have been defined previously; however, there are no clear criteria for failure and worsening after surgery as assessed by patient-reported outcome measures (PROMs).

PURPOSE

We aimed to quantify changes in standard PROMs that most accurately identified failure and worsening after surgery for LSS.

STUDY DESIGN /SETTING

Retrospective analysis of prospective national spine registry data with 12-months follow-up.

PATIENT SAMPLE

We analyzed 10,822 patients aged 50 years and older operated in Norway during a decade, and 8,258 (76%) responded 12 months after surgery.

OUTCOME MEASURES (PROMS)

We calculated final scores, absolute changes, and percentage changes for Oswestry Disability Index (ODI), Numeric Rating Scale (NRS) for back and leg pain (0-10), and EuroQol-5D (EQ-5D). These 12 PROM derivates were compared to the Global Perceived Effect (GPE), a 7-point Likert scale.

METHODS

We used ODI, NRS back and leg pain, and EQ-5D 12 months after surgery to identify patients with failure (no effect) and worsening (clinical deterioration). The corresponding GPE at 12-months was graded as failure (GPE=4-7) and worsening (GPE=6-7) and used as an external criterion. To quantify the most accurate cut-off values corresponding to failure and worsening, we calculated areas under the curves (AUCs) of receiver operating characteristics (ROC) curves for the respective PROM derivates.

RESULTS

Mean (95% CI) age was 68.3 (68.1 - 68.5) years, and 52% were females. There were 1,683 (20%) failures, and 476 (6%) patients were worse after surgery. The mean (95% CI) pre- and postoperative ODIs were 39.8 (39.5 - 40.2) and 23.7 (23.3 - 24.1), respectively. At 12 months, the mean difference (95% CI) in ODI was 16.1 (15.7 - 16.4), and the mean (95% CI) percentage improvement 38.8% (37.8 - 38.8). The PROM derivates identified failure and worsening accurately (AUC>0.80), except for the absolute change in EQ-5D. The ODI derivates were most accurate to identify both failure and worsening. We found that less than 20% improvement in ODI most accurately identified failure (AUC=0.89 [95% CI: 0.88 to 0.90]), and an ODI final score of 39 points or more most accurately identified worsening (AUC =0.91 [95% CI: 0.90 - 0.92]).

CONCLUSIONS

In this national register study, ODI derivates were most accurate to identify both failure and worsening after surgery for degenerative lumbar spinal stenosis. We recommend use of ODI percentage change and ODI final score for further studies of failure and worsening in elective spine surgery.

Surgical Restoration of Sagittal Alignment of the Spine: Correlation with Improved Patient-Reported Outcomes: A Systematic Review and Meta-Analysis

BACKGROUND

The sagittal-plane curvatures of the human spine are the consequence of evolution from quadrupedalism to bipedalism and are needed to maintain the center of mass of the body within the base of support in the bipedal position. Lumbar degenerative disorders can lead to a decrease in lumbar lordosis and thereby affect overall alignment of the spine. However, there is not yet enough direct evidence that surgical restoration of spinal malalignment would lead to a better clinical outcome. Therefore, the aim of this study was to assess the correlation between patient-reported outcomes and actual obtained spinal sagittal alignment in adult patients with lumbar degenerative disorders who underwent surgical treatment.

METHODS

A comprehensive literature search was conducted through databases (PubMed, Cochrane, Web of Science, and Embase). The last search was in November 2018. Risk of bias was assessed with the Newcastle-Ottawa quality assessment scale. A meta-regression analysis was performed.

RESULTS

Of 2,024 unique articles in the original search, 34 articles with 973 patients were included. All studies were either retrospective or prospective cohort studies; no randomized controlled trials were available. A total of 54 relations between preoperative-to-postoperative improvement in patient-reported outcome measures (PROMs) and radiographic spinopelvic parameters were found, of which 20 were eligible for meta-regression analysis. Of these, 2 correlations were significant: pelvic tilt (PT) versus Oswestry Disability Index (ODI) (p = 0.009) and PT versus visual analog scale (VAS) pain (p = 0.008).

CONCLUSIONS

On the basis of the current literature, lower PT was significantly correlated with improved ODI and VAS pain in patients with sagittal malalignment caused by lumbar degenerative disorders that were treated with surgical correction of the sagittal balance.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

State-of-the-art: outcome assessment in adult spinal deformity

Adult spinal deformity (ASD) is a diagnosis that encompasses heterogeneous disorders with an increasing prevalence. This increasing prevalence may be due to greater patient longevity or greater awareness of available treatments. Outcome assessment in ASD has evolved over the last 3 decades from physician-based assessments to a patient-centered perception of improvement. Outcome assessment that is reliable, accurate and responsive to change is especially important in ASD, as surgical treatment is known to carry a high cost and complication rate Glassman (Spine Deform 3:199-203, 2015); Glassman (Spine (Phila Pa 1976) 32: 2764-2770, 2007); Smith (J Neurosurg Spine 25:1-14, 2016). In an era of value-based care, diagnosis associated with such heterogeneity and high cost must provide sound evidence to support the cost versus outcome ratio. Numerous general health and disease specific patient-reported outcome measures (PROMs) have been utilized in ASD. We discuss these instruments in detail in the following state-of-the-art review.

The Scoliosis Research Society adult spinal deformity standard outcome set

PURPOSE

Symptomatic adult spinal deformity (ASD) with an extremely variable presentation with pain, with and without neurogenic leg pain, and/or disturbed sagittal and coronal balance, causes a significant societal burden of disease. It is an important consequence of the aging adult population, generating a plethora of spine-related interventions with variable treatment efficacy and consistently high costs. Recent years have witnessed more than a threefold increase in the prevalence and treatment of ASD, and further increases over the coming decades are expected with the growing elderly population worldwide. The ability to monitor and assess clinical outcomes has not kept pace with these developments. This paper addresses the pressing need to provide a set of common outcome metrics for this growing group of patients with back pain and other disabilities due to an adult spinal deformity.

METHODS

The standard outcome set was created by a panel with global representation, using a thorough modified Delphi procedure. The three-tiered outcome hierarchy (Porter) was used as a framework to capture full cycle of care. The standardized language of the International Classification of Functioning, Disability and Health (WHO-ICF) was used.

RESULTS

Consensus was reached on a core set of 25 WHO-ICF outcome domains ('What to measure'); on the accompanying globally available clinician and patient reported measurement instruments and definitions ('How to measure'), and on the timing of the measurements ('When to measure'). The current work has brought to light domains not routinely reported in the spinal literature (such as pulmonary function, return to work, social participation), and domains for which no adequate instruments have yet been identified (such as how to clinically quantify in routine practice lumbar spinal stenosis, neurogenic claudication, radicular pain, and loss of lower extremity motor function).

CONCLUSION

A standard outcome set was developed for patients undergoing treatment for adult spinal deformity using globally available outcome metrics. The current framework can be considered a reference for further work, and may provide a starting point for routine methodical and systematic monitoring of outcomes. Post-COVID e-health may accelerate the routine capture of these types of data.

Effect of postural changes on in vivo pelvic tilt and functional component anteversion in total hip arthroplasty patients with lumbar disc degenerations

Aims

The complex relationship between acetabular component position and spinopelvic mobility in patients following total hip arthroplasty (THA) renders it difficult to optimize acetabular component positioning. Mobility of the normal lumbar spine during postural changes results in alterations in pelvic tilt (PT) to maintain the sagittal balance in each posture and, as a consequence, markedly changes the functional component anteversion (FCA). This study aimed to investigate the in vivo association of lumbar degenerative disc disease (DDD) with the PT angle and with FCA during postural changes in THA patients.

Methods

A total of 50 patients with unilateral THA underwent CT imaging for radiological evaluation of presence and severity of lumbar DDD. In all, 18 patients with lumbar DDD were compared to 32 patients without lumbar DDD. In vivo PT and FCA, and the magnitudes of changes (ΔPT; ΔFCA) during supine, standing, swing-phase, and stance-phase positions were measured using a validated dual fluoroscopic imaging system.

Results

PT, FCA, ΔPT, and ΔFCA were significantly correlated with the severity of lumbar DDD. Patients with severe lumbar DDD showed marked differences in PT with changes in posture; there was an anterior tilt (-16.6° vs -12.3°, p = 0.047) in the supine position, but a posterior tilt in an upright posture (1.0° vs -3.6°, p = 0.005). A significant decrease in ΔFCA during stand-to-swing (8.6° vs 12.8°, p = 0.038) and stand-to-stance (7.3° vs 10.6°,p = 0.042) was observed in the severe lumbar DDD group.

Conclusion

There were marked differences in the relationship between PT and posture in patients with severe lumbar DDD compared with healthy controls. Clinical decision-making should consider the relationship between PT and FCA in order to reduce the risk of impingement at large ranges of motion in THA patients with lumbar DDD. Cite this article: Bone Joint J 2020;102-B(11):1505–1510.

Effect of postural changes on in vivo pelvic tilt and functional component anteversion in total hip arthroplasty patients with lumbar disc degenerations

AIMS

The complex relationship between acetabular component position and spinopelvic mobility in patients following total hip arthroplasty (THA) renders it difficult to optimize acetabular component positioning. Mobility of the normal lumbar spine during postural changes results in alterations in pelvic tilt (PT) to maintain the sagittal balance in each posture and, as a consequence, markedly changes the functional component anteversion (FCA). This study aimed to investigate the in vivo association of lumbar degenerative disc disease (DDD) with the PT angle and with FCA during postural changes in THA patients.

METHODS

A total of 50 patients with unilateral THA underwent CT imaging for radiological evaluation of presence and severity of lumbar DDD. In all, 18 patients with lumbar DDD were compared to 32 patients without lumbar DDD. In vivo PT and FCA, and the magnitudes of changes (ΔPT; ΔFCA) during supine, standing, swing-phase, and stance-phase positions were measured using a validated dual fluoroscopic imaging system.

RESULTS

PT, FCA, ΔPT, and ΔFCA were significantly correlated with the severity of lumbar DDD. Patients with severe lumbar DDD showed marked differences in PT with changes in posture; there was an anterior tilt (-16.6° vs -12.3°, p = 0.047) in the supine position, but a posterior tilt in an upright posture (1.0° vs -3.6°, p = 0.005). A significant decrease in ΔFCA during stand-to-swing (8.6° vs 12.8°, p = 0.038) and stand-to-stance (7.3° vs 10.6°,p = 0.042) was observed in the severe lumbar DDD group.

CONCLUSION

There were marked differences in the relationship between PT and posture in patients with severe lumbar DDD compared with healthy controls. Clinical decision-making should consider the relationship between PT and FCA in order to reduce the risk of impingement at large ranges of motion in THA patients with lumbar DDD.

Criteria for success after surgery for cervical radiculopathy-estimates for a substantial amount of improvement in core outcome measures

BACKGROUND CONTEXT

Defining clinically meaningful success criteria from patient-reported outcome measures (PROMs) is crucial for clinical audits, research and decision-making.

PURPOSE

We aimed to define criteria for a successful outcome 3 and 12 months after surgery for cervical degenerative radiculopathy on recommended PROMs.

STUDY DESIGN

Prospective cohort study with 12 months follow-up.

PATIENT SAMPLE

Patients operated at one or two levels for cervical radiculopathy included in the Norwegian Registry for Spine Surgery (NORspine) from 2011 to 2016.

OUTCOME MEASURES

Neck disability index (NDI), Numeric Rating Scale for neck pain (NRS-NP) and arm pain (NRS-AP), health-related quality-of-life EuroQol 3L (EQ-5D), general health status (EQ-VAS).

METHODS

We included 2,868 consecutive cervical degenerative radiculopathy patients operated for cervical radiculopathy in one or two levels and included in the Norwegian Registry for Spine Surgery (NORspine). External criterion to determine accuracy and optimal cut-off values for success in the PROMs was the global perceived effect scale. Success was defined as "much better" or "completely recovered." Cut-off values were assessed by analyzing the area under the receiver operating curves for follow-up scores, mean change scores, and percentage change scores.

RESULTS

All PROMs showed high accuracy in defining success and nonsuccess and only minor differences were found between 3- and 12-month scores. At 12 months, the area under the receiver operating curves for follow-up scores were 0.86 to 0.91, change scores were 0.74 to 0.87, and percentage change scores were 0.74 to 0.91. Percentage scores of NDI and NRS-AP showed the best accuracy. The optimal cut-off values for each PROM showed considerable overlap across those operated due to disc herniation and spondylotic foraminal stenosis.

CONCLUSIONS

All PROMs, especially NDI and NRS-AP, showed good to excellent discriminative ability in distinguishing between a successful and nonsuccessful outcome after surgery due to cervical radiculopathy. Percentage change scores are recommended for use in research and clinical practice.

The Natural History of Progression in Adult Spinal Deformity: A Radiographic Analysis

STUDY DESIGN

Historical cohort study.

OBJECTIVE

To evaluate progression in the coronal and sagittal planes in nonsurgical patients with adult spinal deformity (ASD).

METHODS

A retrospective analysis of nonsurgical ASD patients between 2005 and 2017 was performed. Magnitude of the coronal and sagittal planes were compared on the day of presentation and at most recent follow-up. Previous reported prognostic factors for progression in the coronal plane, including the direction of scoliosis, curve magnitude, and the position of the intercrest line (passing through L4 or L5 vertebra), were studied.

RESULTS

Fifty-eight patients were included with a mean follow-up of 59.8 ± 34.5 months. Progression in the coronal plane was seen in 72% of patients. Mean Cobb angle on the day of presentation and most recent follow-up was 37.2 ± 14.6° and 40.8° ± 16.5°, respectively. No significant differences were found in curve progression in left- versus right-sided scoliosis (3.3 ± 7.1 vs 3.7 ± 5.4, P = .81), Cobb angle <30° versus ≥30° (2.6 ± 5.0 vs 4.3 ± 6.5, P = .30), or when the intercrest line passed through L4 rather than L5 vertebra (3.4 ± 5.0° vs 3.8 ± 7.1°, P = .79). No significant differences were found in the sagittal plane between presentation and most recent follow-up.

CONCLUSIONS

This is the first study that describes progression in the coronal and sagittal planes in nonsurgical patients with ASD. Previous reported prognostic factors were not confirmed as truly relevant. Although progression appears to occur, large variation exists and these results may not be directly applicable to the individual patient.

Microdiscectomy for Lumbar Disc Herniation: A Single-Center Observational Study

OBJECTIVE

To examine outcomes and complications following first-time lumbar microdiscectomy.

METHODS

Prospective data for patients operated on between May 2007 and July 2016 were obtained from the Norwegian Registry for Spine Surgery. The primary outcome was change in Oswestry Disability Index (ODI) score at 1 year. Secondary endpoints were change in quality of life measured with EuroQol 5 Dimensions, back and leg pain measured with numeric rating scales, and perioperative complications within 3 months of surgery.

RESULTS

For all enrolled patients (N = 1219) enrolled, mean improvement in ODI at 1 year was 33.3 points (95% confidence interval [CI] 31.7 to 34.9, P < 0.001). Mean improvement in EuroQol 5 Dimensions at 1 year of 0.52 point (95% CI 0.49 to 0.55, P < 0.001) represents a large effect size (Cohen's d = 1.6). Mean improvements in back pain and leg pain numeric rating scales were 3.9 points (95% CI 3.6 to 4.1, P < 0.001) and 5.0 points (95% CI 4.8 to 5.2, P < 0.001), respectively. There were 18 surgical complications in 1219 patients and 63 medical complications in 846 patients. The most common complication was micturition problems at 3 months following surgery (n = 25, 2.1%). In multivariate analysis, ODI scores of 21-40 (hazard ratio [HR] 14.5, 95% CI 1.1 to 27.9, P = 0.035), 41-60 (HR 27.5, 95% CI 13.4 to 41.7, P < 0.001), 61-80 (HR 47.4, 95% CI 33.4 to 61.4, P < 0.001) and >81 (HR 66.7, 95% CI 51.1 to 82.2, P < 0.001) were identified as positive predictors for ODI improvement at 1 year, whereas age ≥65 (HR -0.9, 95% CI -0.3 to -1.5, P = 0.004) was identified as a negative predictor for ODI improvement.

CONCLUSIONS

Microdiscectomy for lumbar disc herniation is an effective and safe treatment.

Quality and Safety Improvement in Spine Surgery

STUDY DESIGN

Review article.

OBJECTIVES

A narrative review of the literature on the current advances and limitations in quality and safety improvement initiatives in spine surgery.

METHODS

A comprehensive literature search was performed using Ovid MEDLINE focusing on 3 preidentified concepts: (1) quality and safety improvement, (2) reporting of outcomes and adverse events, and (3) prediction model and practice guidelines. The search was conducted under appropriate subject headings and using relevant text words. Articles were screened, and manuscripts relevant to this discussion were included in the narrative review.

RESULTS

Quality and safety improvement remains a major research focus attracting investigators from the global spine community. Multiple databases and registries have been developed for the purpose of generating data and monitoring the progress of quality and safety improvement initiatives. The development of various prediction models and clinical practice guidelines has helped shape the care of spine patients in the modern era. With the reported success of exemplary programs initiated by the Northwestern and Seattle Spine Team, other quality and safety improvement initiatives are anticipated to follow. However, despite these advancements, the reporting metrics for outcomes and adverse events remain heterogeneous in the literature.

CONCLUSION

Constant surveillance and continuous improvement of the quality and safety of spine treatments is imperative in modern health care. Although great advancement has been made, issues with reporting outcomes and adverse events persist, and improvement in this regard is certainly needed.

Long-term outcome of fusion for degenerative disc disease in the lumbar spine

Aims

Chronic low back pain due to degenerative disc disease is sometimes treated with fusion. We compared the outcome of three different fusion techniques in the Swedish Spine Register: noninstrumented posterolateral fusion (PLF), instrumented posterolateral fusion (IPLF), and interbody fusion (IBF).

Patients and Methods

A total of 2874 patients who were operated on at one or two lumbar levels were followed for a mean of 9.2 years (3.6 to 19.1) for any additional lumbar spine surgery. Patient-reported outcome data were available preoperatively (n = 2874) and at one year (n = 2274), two years (n = 1958), and a mean of 6.9 years (n = 1518) postoperatively and consisted of global assessment and visual analogue scales of leg and back pain, Oswestry Disability Index, EuroQol five-dimensional index, 36-Item Short-Form Health Survey, and satisfaction with treatment. Statistical analyses were performed with competing-risks proportional hazards regression or analysis of covariance, adjusted for baseline variables.

Results

The number of patients with additional surgery were 32/183 (17%) in the PLF group, 229/1256 (18%) in the IPLF group, and 439/1435 (31%) in the IBF group. With the PLF group as a reference, the hazard ratio for additional lumbar surgery was 1.16 (95% confidence interval (CI) 0.78 to 1.72) for the IPLF group and 2.13 (95% CI 1.45 to 3.12) for the IBF group. All patient-reported outcomes improved after surgery (p < 0.001) but were without statistically significant differences between the groups at the one-, two- and 6.9-year follow-ups (all p ≥ 0.12).

Conclusion

The addition of interbody fusion to posterolateral fusion was associated with a higher risk for additional surgery and showed no advantages in patient-reported outcome Cite this article: Bone Joint J 2019;101-B:1526–1533

[Data content of the TraumaRegister DGU® : Results of a random sample control]

BACKGROUND

Registries are becoming increasingly more important in clinical research. The TraumaRegister DGU® of the German Society for Trauma Surgery plays an excellent role with respect to the care of severely injured patients.

AIM

Within the framework of this investigation the quality of data provided by this registry was to be verified.

MATERIAL AND METHODS

Certified hospitals participating in the TraumaNetzwerk DGU® of the German Society for Trauma Surgery are obliged to submit data of treated severely injured patients to the TraumaRegister DGU®. Participating hospitals have to undergo a re-certification process every 3 years. Within the framework of this re-audit, data from 5 out of 8 randomly chosen patient cases included in the registry are controlled and compared to the patient files of the certified hospital. In the present investigation discrepancies concerning data provided were documented and the pattern of deviation was analyzed.

RESULTS

The results of 1075 re-certification processes carried out in 631 hospitals including the documentation of 5409 checked patient cases from 2012-2017 were analyzed. The highest number of discrepancies detected concerned the documented time until initial CT (15.8%) and the lowest concerned the discharge site (3.2%). The majority of data sheets with discrepancies showed deviations in only one out of seven checked parameters. Interestingly, large trauma centers with a high throughput of severely injured patients showed the most deviations.

CONCLUSION

The present investigation underlines the importance of standardized checks concerning data provided for registries in order to be able to guarantee an improvement in entering data.

Estimating Health Utility in Patients Presenting for Spine Surgery Using Patient-reported Outcomes Measurement Information System (PROMIS) Health Domains

STUDY DESIGN

Prospective cohort study.

OBJECTIVE

To evaluate whether Patient-Reported Outcomes Measurement Information System (PROMIS) health domains can effectively estimate health utility index values for patients presenting for spine surgery.

SUMMARY OF BACKGROUND DATA

Stable estimates of health utility are required to determine cost-effectiveness of spine surgery. There are no established methods to estimate health utility using PROMIS.

METHODS

We enrolled 439 patients with spine disease (mean age, 54 ± 18 yrs) presenting for surgery and assessed their health using the Medical Outcomes Study Short Form-12, version 2 (SF-12v2) and PROMIS domains. Standard health utility values were estimated from the SF-12v2. Participants were randomly assigned to derivation or validation cohort. In the derivation cohort, health utility values were estimated as a function of PROMIS domains using regression models. Model fit statistics determined the most parsimonious health utility estimation equation (HEE). In the validation cohort, values were calculated using the HEE. Estimated health utility values were correlated with SF-12v2-derived health utility values.

RESULTS

Mean preoperative health utility was 0.492 ± 0.008 and was similar between the two cohorts. All PROMIS health domains were significantly associated with health utility except Anxiety (P = 0.830) and Sleep Disturbance (P = 0.818). The final HEE was:Health Utility (est) = 0.70742 - 0.00471 × Pain + 0.00647 × Physical function - 0.00316 × Fatigue - 0.00214 × Depression + 0.00317 × Satisfaction with Participation in Social Roles.The estimation model accounted for 74% of observed variation in health utility. In the validation sample, mean health utility was 0.5033 ± 0.1684 and estimated health utility was 0.4966 ± 0.1342 (P = 0.401). These measures were strongly correlated (rho = 0.834).

CONCLUSION

Our results indicate that PROMIS provides a reasonable estimate of health utility in adults presenting for lumbar or cervical spine surgery.

LEVEL OF EVIDENCE

1.

Prediction of Oswestry Disability Index (ODI) using PROMIS-29 in a national sample of lumbar spine surgery patients

PURPOSE

The primary purpose was to examine the measurement properties of the PROMIS-29 to better understand its use in patients undergoing spine surgery. A secondary objective was to calculate a predictive equation between PROMIS-29 and ODI, to allow clinicians and researchers to determine a predicted ODI score based on PROMIS short form scores.

METHODS

719 patients with PROMIS v2.0 and ODI responses were queried from the quality outcomes database. Validity was assessed using coefficient omega, ceiling/floor effects, and confirmatory factor analysis. Multivariable regression predicting ODI scores from PROMIS-29 domains was used to create a predictive equation. Predicted ODI scores were plotted against ODI scores to determine how well PROMIS-29 domains predicted ODI.

RESULTS

Results showed good reliability and validity of PROMIS-29 in patients undergoing lumbar spine surgery: convergent and discriminant validity, low floor/ceiling effects, and unidimensional domains. The conversion equation used 6 PROMIS-29 domains (ODI_% =  37.847- 1.475*[PF_raw] + 1.842*[PAIN_raw] + 0.557*[SD_raw] - 0.642*[SR_raw] + 0.478*[PI_raw] + 0.295*[DEP_raw]). Correlation between the predicted and actual ODI scores was R = 0.88, R² = 0.78, suggesting that the equation predicted ODI scores that are strongly correlated with actual ODI scores.

CONCLUSIONS

Good measurement properties support the use of PROMIS-29 in spine surgery patients. Findings suggest accurate ODI scores can be derived from PROMIS-29 domains. Clinicians who want to move from ODI to PROMIS-29 can use this equation to obtain estimated ODI scores when only collecting PROMIS-29. These results support the idea that PROMIS-29 domains have the potential to replace disease-specific traditional PROMs.

Improving Complex Pediatric and Adult Spine Care While Embracing the Value Equation

INTRODUCTION

Value in health care is defined as the quotient of outcomes to cost. Both pediatric and adult spinal deformity surgeries are among the most expensive procedures offered today. With high variability in both outcomes and costs in spine surgery today, surgeons will be expected to consider long-term cost effectiveness when comparing treatment options.

METHODS

We summarize various methods by which value can be increased in complex spine surgery, both through the improvement of outcomes and the reduction of cost. These methods center around standardization, team-based and collaborative approaches, rigorous outcomes tracking through dashboards and registries, and continuous process improvement.

RESULTS

This manuscript reviews the expert opinion of leading spine specialists on the improvement of safety, quality and improvement of value of pediatric and adult spinal surgery.

CONCLUSION

Without surgeon leadership in this arena, suboptimal solutions may result from the isolated intervention of regulatory bodies or payer groups. The cooperative development of standardized, team-based approaches in complex spine surgery will lead to the high-quality, high-value care for patients.

Follow-up score, change score or percentage change score for determining clinical important outcome following surgery? An observational study from the Norwegian registry for Spine surgery evaluating patient reported outcome measures in lumbar spinal stenosis and lumbar degenerative spondylolisthesis

Background

Assessment of outcomes for spinal surgeries is challenging, and an ideal measurement that reflects all aspects of importance for the patients does not exist. Oswestry Disability Index (ODI), EuroQol (EQ-5D) and Numeric Rating Scales (NRS) for leg pain and for back pain are commonly used patients reported outcome measurements (PROMs). Reporting the proportion of individuals with an outcome of clinical importance is recommended. Knowledge of the ability of PROMs to identify clearly improved patients is essential. The purpose of this study was to search cut-off criteria for PROMs that best reflect an improvement considered by the patients to be of clinical importance.

Methods

The Global Perceived Effect scale was utilized to evaluate a clinically important outcome 12 months after surgery. The cut-offs for the PROMs that most accurately distinguish those who reported ‘completely recovered’ or ‘much improved’ from those who reported ‘slightly improved’, unchanged’, ‘slightly worse’, ‘much worse’, or ‘worse than ever’ were estimated. For each PROM, we evaluated three candidate response parameters: the (raw) follow-up score, the (numerical) change score, and the percentage change score.

Results

We analysed 3859 patients with Lumbar Spinal Stenosis [(LSS); mean age 66; female gender 50%] and 617 patients with Lumbar Degenerative Spondylolisthesis [(LDS); mean age 67; 72% female gender]. The accuracy of identifying ‘completely recovered’ and ‘much better’ patients was generally high, but lower for EQ-5D than for the other PROMs. For all PROMs the accuracy was lower for the change score than for the follow-up score and the percentage change score, especially among patients with low and high PROM scores at baseline.

The optimal threshold for a clinically important outcome was ≤24 for ODI, ≥0.69 for EQ-5D, ≤3 for NRS leg pain, and ≤ 4 for NRS back pain, and, for the percentage change score, ≥30% for ODI, ≥40% for NRS leg pain, and ≥ 33% for NRS back pain. The estimated cut-offs were similar for LSS and for LDS.

Conclusion

For estimating a ‘success’ rate assessed by a PROM, we recommend using the follow-up score or the percentage change score. These scores reflected a clinically important outcome better than the change score.

Spine Registries: Where Do We Stand?

To curb the unsustainable rise in health care costs, novel payment models are being explored which focus on value rather than volume. Underlying this reform is an accurate understanding of costs and outcomes. The Patient Protection and Affordable Care Act, the Institute of Medicine, and the Agency for Healthcare Research and Quality have specifically advocated for the use of registries to help define the real-world effectiveness of surgical interventions to help guide health care reform. Registries can help define value by documenting surgical efficacy, and specifically by reporting patient-based outcome measures. Over the past 10 years, several spine registries have been initiated and some others have expanded. These are providing a repository of evidence for surgical value. Herein, we will review the components of a well-designed registry and provide examples of such registries and their impact on health care delivery.

Spine surgery registries: hope for evidence-based spinal care?

This study aimed to describe the perceptions of decision-makers in major orthopedic centers regarding the value, implementation and use of spine surgery registries. A 33-item survey was sent to CEOs and heads of spine surgery of the International Society of Orthopedic Centers (ISOC). ISOC includes 21 hospitals worldwide with a special focus on high-quality musculoskeletal care. Twelve out of 20 member centers (60%) replied to the survey. Seven have working registries; 5 in Europe and 2 in North America. The estimations for the cost/year were distributed more evenly: $10,000 [2], $20,000 [1], $50,000 [1]. Society cannot afford unnecessary surgery nor renounce to cure patients with effective treatments. Spine surgery registries provide high levels of evidence. The cost of implementing a registry is limited in comparison to RCTs. Spine registries can pragmatically fill our knowledge gap by turning every operated patient into a study participant.

Shaping conservative spinal services with the Spine Tango Registry

PURPOSE

This study reports the results of a registry data collection project within a secondary care spinal osteopathy service.

METHODS

Clinical and demographic data were collected using the Spine Tango Conservative registry data collection tool. Outcomes were assessed using the Numerical Pain Rating Scale (NPRS), Oswestry Disability Index (ODI), Neck Disability Index (NDI), COMI Low Back Conservative (COMI-LBC), COMI Neck Conservative (COMI-NC) and EQ5D. Global treatment outcome (GTO), satisfaction with care and therapeutic complications were reported using the Spine Tango Patient Self Assessment form (STPSA). The correlation of GTO and PROM change scores was analysed using Spearman's rank correlation coefficient.

RESULTS

262 patients presented during the study period. 100% of patients had chronic spinal pain and 98.8% had previously received other interventions for the same episode. Mean (standard deviation) improvements by PROM: NPRS low back 2.1 (2.5); NPRS neck 2.3 (2.3); COMI-LBC 2.1 (2.2); COMI-NC 2.0 (1.7); ODI 10.5 (12.1); NDI 14.5 (12.2); EQ5D 0.2 (0.3). 83.2% of patients reported that osteopathy had 'helped a lot' or 'helped'. 96.2% of patients were 'very satisfied' or 'satisfied' with care. There were no serious therapeutic complications.

CONCLUSIONS

The secondary care spinal osteopathy service demonstrated high satisfaction, few therapeutic complications and positive outcomes on all PROMs. Registry participation has facilitated robust clinical governance and the data support the use of osteopaths to deliver a conservative spinal service in this setting. Registry data collection is a significant administrative and clinical task which should be structured to minimise burden on patients and resources. These slides can be retrieved under Electronic Supplementary Material.

Defining a core outcome set for adolescent and young adult patients with a spinal deformity

Background and purpose - Routine outcome measurement has been shown to improve performance in several fields of healthcare. National spine surgery registries have been initiated in 5 Nordic countries. However, there is no agreement on which outcomes are essential to measure for adolescent and young adult patients with a spinal deformity. The aim of this study was to develop a core outcome set (COS) that will facilitate benchmarking within and between the 5 countries of the Nordic Spinal Deformity Society (NSDS) and other registries worldwide. Material and methods - From August 2015 to September 2016, 7 representatives (panelists) of the national spinal surgery registries from each of the NSDS countries participated in a modified Delphi study. With a systematic literature review as a basis and the International Classification of Functioning, Disability and Health framework as guidance, 4 consensus rounds were held. Consensus was defined as agreement between at least 5 of the 7 representatives. Data were analyzed qualitatively and quantitatively. Results - Consensus was reached on the inclusion of 13 core outcome domains: "satisfaction with overall outcome of surgery", "satisfaction with cosmetic result of surgery", "pain interference", physical functioning", "health-related quality of life", "recreation and leisure", "pulmonary fatigue", "change in deformity", "self-image", "pain intensity", "physical function", "complications", and "re-operation". Panelists agreed that the SRS-22r, EQ-5D, and a pulmonary fatigue questionnaire (yet to be developed) are the most appropriate set of patient-reported measurement instruments that cover these outcome domains. Interpretation - We have identified a COS for a large subgroup of spinal deformity patients for implementation and validation in the NSDS countries. This is the first study to further develop a COS in a global perspective.

Criteria for failure and worsening after surgery for lumbar disc herniation: a multicenter observational study based on data from the Norwegian Registry for Spine Surgery

PURPOSE

In clinical decision-making, it is crucial to discuss the probability of adverse outcomes with the patient. A large proportion of the outcomes are difficult to classify as either failure or success. Consequently, cutoff values in patient-reported outcome measures (PROMs) for "failure" and "worsening" are likely to be different from those of "non-success". The aim of this study was to identify dichotomous cutoffs for failure and worsening, 12 months after surgical treatment for lumbar disc herniation, in a large registry cohort.

METHODS

A total of 6840 patients with lumbar disc herniation were operated and followed for 12 months, according to the standard protocol of the Norwegian Registry for Spine Surgery (NORspine). Patients reporting to be unchanged or worse on the Global Perceived Effectiveness (GPE) scale at 12-month follow-up were classified as "failure", and those considering themselves "worse" or "worse than ever" after surgery were classified as "worsening". These two dichotomous outcomes were used as anchors in analyses of receiver operating characteristics (ROC) to define cutoffs for failure and worsening on commonly used PROMs, namely, the Oswestry Disability Index (ODI), the EuroQuol 5D (EQ-5D), and Numerical Rating Scales (NRS) for back pain and leg pain.

RESULTS

"Failure" after 12 months for each PROM, as an insufficient improvement from baseline, was (sensitivity and specificity): ODI change <13 (0.82, 0.82), ODI% change <33% (0.86, 0.86), ODI final raw score >25 (0.89, 0.81), NRS back-pain change <1.5 (0.74, 0.86), NRS back-pain % change <24 (0.85, 0.81), NRS back-pain final raw score >5.5 (0.81, 0.87), NRS leg-pain change <1.5 (0.81, 0.76), NRS leg-pain % change <39 (0.86, 0.81), NRS leg-pain final raw score >4.5 (0.91, 0.85), EQ-5D change <0.10 (0.76, 0.83), and EQ-5D final raw score >0.63 (0.81, 0.85). Both a final raw score >48 for the ODI and an NRS >7.5 were indicators for "worsening" after 12 months, with acceptable accuracy.

CONCLUSION

The criteria with the highest accuracy for defining failure and worsening after surgery for lumbar disc herniation were an ODI percentage change score <33% for failure and a 12-month ODI raw score >48. These cutoffs can facilitate shared decision-making among doctors and patients, and improve quality assessment and comparison of clinical outcomes across surgical units. In addition to clinically relevant improvements, we propose that rates of failure and worsening should be included in reporting from clinical trials.

Measuring outcomes in adult spinal deformity surgery: a systematic review to identify current strengths, weaknesses and gaps in patient-reported outcome measures

PURPOSE

Adult spinal deformity (ASD) causes severe disability, reduces overall quality of life, and results in a substantial societal burden of disease. As healthcare is becoming more value based, and to facilitate global benchmarking, it is critical to identify and standardize patient-reported outcome measures (PROMs). This study aims to identify the current strengths, weaknesses, and gaps in PROMs used for ASD.

METHODS

Studies were included following a systematic search in multiple bibliographic databases between 2000 and 2015. PROMs were extracted and linked to the outcome domains of WHO's International Classification of Functioning and Health (ICF) framework. Subsequently, the clinimetric quality of identified PROMs was evaluated.

RESULTS

The literature search identified 144 papers that met the inclusion criteria, and nine frequently used PROMs were identified. These covered 29 ICF outcome domains, which could be grouped into three of the four main ICF chapters: body function (n = 7), activity and participation (n = 19), environmental factors (n = 3), and body structure (n = 0). A low quantity (n = 3) of papers was identified that studied the clinimetric quality of PROMs. The Scoliosis Research Society (SRS)-22 has the highest level of clinimetric quality for ASD.

CONCLUSIONS

Outcome domains related to mobility and pain were well represented. We identified a gap in current outcome measures regarding neurological and pulmonary function. In addition, no outcome domains were measured in the ICF chapter body structure. These results will serve as a foundation for the process of seeking international consensus on a standard set of outcome domains, accompanied PROMs and contributing factors to be used in future clinical trials and spine registries.

Outcomes of Posterolateral Fusion with and without Instrumentation and of Interbody Fusion for Isthmic Spondylolisthesis: A Prospective Study

BACKGROUND

Various methods for the treatment of isthmic spondylolisthesis are available. The aim of this study was to compare outcomes after posterolateral fusion without instrumentation, posterolateral fusion with instrumentation, and interbody fusion.

METHODS

The Swedish Spine Register was used to identify 765 patients who had been operated on for isthmic spondylolisthesis and had at least preoperative and 2-year outcome data; 586 of them had longer follow-up (a mean of 6.9 years). The outcome measures were a global assessment of leg and back pain, the Oswestry Disability Index (ODI), the EuroQol-5 Dimensions (EQ-5D) Questionnaire, the Short Form-36 (SF-36), a visual analog scale (VAS) for back and leg pain, and satisfaction with treatment. Data on additional lumbar spine surgery was searched for in the register, with the mean duration of follow-up for this variable being 10.6 years after the index procedure. Statistical analyses were performed with analysis of covariance or competing-risks proportional hazards regression, adjusted for baseline differences in the studied variables, smoking, employment status, and level of fusion.

RESULTS

Posterolateral fusion without instrumentation was performed in 102 patients; posterolateral fusion with instrumentation, in 452; and interbody fusion, in 211. At 1 year, improvement was reported in the global assessment for back pain by 54% of the patients who had posterolateral fusion without instrumentation, 68% of those treated with posterolateral fusion with instrumentation, and 70% of those treated with interbody fusion (p = 0.009). The VAS for back pain and reported satisfaction with treatment showed similar patterns (p = 0.003 and p = 0.017, respectively), whereas other outcomes did not differ among the treatment groups at 1 year. At 2 years, the global assessment for back pain indicated improvement in 57% of the patients who had undergone posterolateral fusion without instrumentation, 70% of those who had posterolateral fusion with instrumentation, and 71% of those treated with interbody fusion (p = 0.022). There were no significant outcome differences at the mean 6.9-year follow-up interval. There was an increased hazard ratio for additional lumbar spine surgery after interbody fusion (4.34; 95% confidence interval [CI] = 1.71 to 11.03) and posterolateral fusion with instrumentation (2.56; 95% CI = 1.02 to 6.42) compared with after posterolateral fusion without instrumentation (1.00; reference).

CONCLUSIONS

Fusion with instrumentation, with or without interbody fusion, was associated with more improvement in back pain scores and higher satisfaction with treatment compared with fusion without instrumentation at 1 year, but the difference was attenuated with longer follow-up. Fusion with instrumentation was associated with a significantly higher risk of additional spine surgery.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.