Risk Factors for Reoperation in Patients Treated Surgically for Lumbar Stenosis: A Subanalysis of the 8-year Data From the SPORT Trial

The attainment of a patient acceptable symptom state in patients undergoing revision spine fusion

INTRODUCTION

Revision lumbar fusion is most commonly due to nonunion, adjacent segment disease (ASD), or recurrent stenosis, but it is unclear if diagnosis affects patient outcomes. The primary aim of this study was to assess whether patients achieved the patient acceptable symptom state (PASS) or minimal clinically important difference (MCID) after revision lumbar fusion and assess whether this was influenced by the indication for revision.

METHODS

We retrospectively identified all 1-3 level revision lumbar fusions at a single institution. Oswestry Disability Index (ODI) was collected at preoperative, three-month postoperative, and one-year postoperative time points. The MCID was calculated using a distribution-based method at each postoperative time point. PASS was set at the threshold of ≤ 22.

RESULTS

We identified 197 patients: 56% with ASD, 28% with recurrent stenosis, and 15% with pseudarthrosis. The MCID for ODI was 10.05 and 10.23 at three months and one year, respectively. In total, 61% of patients with ASD, 52% of patients with nonunion, and 65% of patients with recurrent stenosis achieved our cohort-specific MCID at one year postoperatively with ASD (p = 0.78). At one year postoperatively, 33.8% of ASD patients, 47.8% of nonunion patients, and 37% of patients with recurrent stenosis achieved PASS without any difference between indication (p = 0.47).

CONCLUSIONS

The majority of patients undergoing revision spine fusion experience significant postoperative improvements regardless of the indication for revision. However, a large proportion of these patients do not achieve the patient acceptable symptom state. While revision spine surgery may offer substantial benefits, these results underscore the need to manage patient expectations.

Systematic Review and Meta-Analysis of the Effect of Osteoporosis on Reoperation Rates and Complications after Surgical Management of Lumbar Degenerative Disease

BACKGROUND

There is considerable heterogeneity in findings and a lack of consensus regarding the interplay between osteoporosis and outcomes in patients with lumbar degenerative spine disease. Therefore, the purpose of this systematic review and meta-analysis was to gather and analyze existing data on the effect of osteoporosis on radiographic, surgical, and clinical outcomes following surgery for lumbar degenerative spinal disease.

METHODS

A systematic review was performed to determine the effect of osteoporosis on the incidence of adverse outcomes after surgical intervention for lumbar degenerative spinal diseases. The approach focused on the radiographic outcomes, reoperation rates, and other medical and surgical complications. Subsequently, a meta-analysis was performed on the eligible studies.

RESULTS

The results of the meta-analysis suggested that osteoporotic patients experienced increased rates of adjacent segment disease (ASD; p=0.015) and cage subsidence (p=0.001) while demonstrating lower reoperation rates than non-osteoporotic patients (7.4% vs. 13.1%; p=0.038). The systematic review also indicated that the length of stay, overall costs, rates of screw loosening, and rates of wound and other medical complications may increase in patients with a lower bone mineral density. Fusion rates, as well as patient-reported and clinical outcomes, did not differ significantly between osteoporotic and non-osteoporotic patients.

CONCLUSIONS

Osteoporosis was associated with an increased risk of ASD, cage migration, and possibly postoperative screw loosening, as well as longer hospital stays, incurring higher costs and an increased likelihood of postoperative complications. However, a link was not established between osteoporosis and poor clinical outcomes.

Incidence of subsequent surgical decompression following minimally invasive approaches to treat lumbar spinal stenosis: A retrospective review

BACKGROUND CONTEXT

Surgical decompression is the definitive treatment for managing symptomatic lumbar spinal stenosis; however, select patients are poor surgical candidates. Consequently, minimally invasive procedures have gained popularity, but there exists the potential for failure of therapy necessitating eventual surgical decompression.

PURPOSE

To evaluate the incidence and characteristics of patients who require surgical decompression following minimally invasive procedures to treat lumbar spinal stenosis.

STUDY DESIGN/SETTING

Retrospective review.

PATIENT SAMPLE

Patients who underwent minimally invasive procedures for lumbar spinal stenosis (Percutaneous Image-guided Lumbar Decompression [PILD] or interspinous spacer device [ISD]) and progressed to subsequent surgical decompression within 5 years.

OUTCOME MEASURES

The primary outcome was the rate of surgical decompression within 5 years following the minimally invasive approach. Secondary outcomes included demographic and comorbid factors associated with increased odds of requiring subsequent surgery.

METHODS

Patient data were collected using the PearlDiver-Mariner database. The rate of subsequent decompression was described as a percentage while univariable and multivariable regression analysis was used for the analysis of predictors.

RESULTS

A total of 5278 patients were included, of which 3222 (61.04%) underwent PILD, 1959 (37.12%) underwent ISD placement, and 97 (1.84%) had claims for both procedures. Overall, the incidence of subsequent surgical decompression within 5 years was 6.56% (346 of 5278 patients). Variables associated with a significantly greater odds ratio (OR) [95% confidence interval (CI)] of requiring subsequent surgical decompression included male gender and a prior history of surgical decompression by 1.42 ([1.14, 1.77], p = 0.002) and 2.10 times ([1.39, 3.17], p < 0.001), respectively. In contrast, age 65 years and above, a diagnosis of obesity, and a Charlson Comorbidity Index score of three or greater were associated with a significantly reduced OR [95% CI] by 0.64 ([0.50, 0.81], p < 0.001), 0.62 ([0.48, 0.81], p < 0.001), and 0.71 times ([0.56, 0.91], p = 0.007), respectively.

CONCLUSIONS

Minimally invasive procedures may provide an additional option to treat symptomatic lumbar spinal stenosis in patients who are poor surgical candidates or who do not desire open decompression; however, there still exists a subset of patients who will require subsequent surgical decompression. Factors such as gender and prior surgical decompression increase the likelihood of subsequent surgery, while older age, obesity, and a higher Charlson Comorbidity Index score reduce it. These findings aid in selecting suitable surgical candidates for better outcomes in the elderly population with lumbar spinal stenosis.

Screening patients requiring secondary lumbar surgery for degenerative lumbar spine diseases: a nationwide sample cohort study

This study aims to identify healthcare costs indicators predicting secondary surgery for degenerative lumbar spine disease (DLSD), which significantly impacts healthcare budgets. Analyzing data from the National Health Insurance Service-National Sample Cohort (NHIS-NSC) database of Republic of Korea (ROK), the study included 3881 patients who had surgery for lumbar disc herniation (LDH), lumbar spinal stenosis without spondylolisthesis (LSS without SPL), lumbar spinal stenosis with spondylolisthesis (LSS with SPL), and spondylolysis (SP) from 2006 to 2008. Patients were categorized into two groups: those undergoing secondary surgery (S-group) and those not (NS-group). Surgical and interim costs were compared, with S-group having higher secondary surgery costs ($1829.59 vs $1618.40 in NS-group, P = 0.002) and higher interim costs ($30.03; 1.86% of initial surgery costs vs $16.09; 0.99% of initial surgery costs in NS-group, P < 0.0001). The same trend was observed in LDH, LSS without SPL, and LSS with SPL (P < 0.0001). Monitoring interim costs trends post-initial surgery can effectively identify patients requiring secondary surgery.

Risk factors for early reoperation in patients after posterior lumbar interbody fusion surgery. A propensity-matched cohort analysis

BACKGROUND

Reoperation is usually associated with poor results and increased morbidity and hospital costs. However, the rates, causes, and risk factors for reoperation in patients undergoing lumbar spinal fusion surgery remain controversial. This study aimed to identify the risk factors for early reoperation after posterior lumbar interbody fusion surgery and to compare the clinical outcomes between patients who underwent reoperation and those who did not.

METHODS

We investigated a multicenter medical record database of 1263 patients who underwent posterior lumbar interbody fusion surgery between 2012 and 2015. A total of 72 (5.7%) reoperations within two years after surgery were identified and were propensity-matched for age, sex, number of fusion segments, and surgeon's experience.

RESULTS

We analyzed a total of 114 patients (57 who underwent reoperation (R group) and 57 who did not (C group)). The mean age was 62.6 ± 13.4 years, with 78 men and 36 women. The mean number of fused segments was 1.2 ± 0.5. Surgical site infection was the most common cause of reoperation. There were significant differences in the incidence of diabetes mellitus (p = 0.024), preoperative ambulation status (p = 0.046), and ASA grade (p < 0.001) between the C and R groups. The recovery rate of the Japanese Orthopaedic Association score was significantly lower in the R group compared to the C group (R: 50.5 ± 28.8%, C: 63.9 ± 33.7%, p = 0.024). There were significant differences in the bone fusion rate (R: 63.2%, C: 96.5%, p < 0.001) and incidence of screw loosening (R: 31.6%; C: 10.5%; p = 0.006).

CONCLUSION

Diabetes mellitus, preoperative ambulation status, and ASA grade were significant risk factors for early reoperation following posterior lumbar interbody fusion surgery. The patients who underwent early reoperation had worse clinical outcomes than those who did not.

Reoperations After Percutaneous Endoscopic Transforaminal Decompression for Treating Lumbar Spinal Stenosis: Incidence and Predictors

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

The main purpose of the present study was to report the incidence and identify predictors of reoperation in patients with lumbar spinal stenosis (LSS) treated with percutaneous endoscopic transforaminal decompression (PETD).

METHODS

This study retrospectively reviewed consecutive patients with LSS who underwent PETD at our center between January 2016 and July 2020. The incidence of reoperations was calculated. We then designed a surgical period-matched case-control study to identify predictors among demographic data, clinical baseline data, and imaging parameters.

RESULTS

This study identified 496 eligible patients. 33 (6.7%) patients underwent reoperation with a mean follow-up of 3 years, consisting 22 (4.4%) at the index level and 11 (2.2%) at the adjacent levels. There were significant differences in age and age-adjusted Charlson comorbidity index (AACCI) between the two groups, with younger age (P = .004) and lower AACCI (P = .019) in reoperation group. Age was identified as the sole independent predictor (P = .006). The duration of symptoms ≥12 months (P = .034) and the presence of heart problems (P = .012) were recognized as specific predictors among patients younger than 65 years.

CONCLUSIONS

In a mean follow-up of 3 years, the incidence of reoperation in LSS treated with PETD was 6.7%. A younger age was the independent predictor for reoperation. Younger patients with the duration of symptoms ≥12 months or without heart problems were more likely to undergo a second operation. Prospective randomized controlled trials are required to confirm these findings.

Midterm Outcomes of Muscle-Preserving Posterior Lumbar Decompression via Sagittal Splitting of the Spinous Process: Minimum 5-Year Follow-up

Background

To overcome several disadvantages of conventional laminectomy for degenerative lumbar spinal stenosis (DLSS), several types of minimally invasive surgery have been developed. The purpose of the present study was to report the clinical and radiological mid-term outcomes of spinous process-splitting decompression (SPSD) for DLSS.

Methods

Seventy-three consecutive patients underwent SPSD between September 2014 and March 2016. Of these, 42 (70 segments) who had at least 5 years of follow-up were analyzed retrospectively. The visual analog scale for back pain and leg pain, Oswestry disability index, and walking distance without resting were scored to assess clinical outcomes at the preoperative and final follow-up. A subgroup analysis was performed according to the union status of the split spinous processes (SPs). For radiological outcomes, slip in the neutral position as a static parameter, anterior flexion-neutral translation, and posterior extension-neutral translation as a dynamic parameter were measured before and at the final follow-up after surgery. Spinopelvic parameters were also measured. Reoperation rate at the index levels was investigated, and predictive risk factors for reoperation were evaluated using multivariate logistic regression. Survival analysis was performed with reoperation as the endpoint to estimate the longevity of the SPSD for DLSS.

Results

All clinical outcomes improved significantly at the final follow-up compared to those at the initial visit (p < 0.05). The clinical outcomes did not differ according to the union status of the split SP. There were no cases of definite segmental instability and no significant changes in the static or dynamic parameters after surgery. Sacral slope and lumbar lordosis increased, and pelvic tilt decreased significantly at the follow-up (p < 0.05), despite no significant change in the sagittal vertical axis. The mean longevity of the procedure before the reoperation was 82.9 months. Five patients (11.9%) underwent reoperation at a mean of 52.2 months after the SPSD. There were no significant risk factors for reoperation; however, the preoperative severity of foraminal stenosis had an odds ratio of 7.556 (p = 0.064).

Conclusions

SPSD for DLSS showed favorable clinical and radiological outcomes at the mid-term follow-up. SPSD could be a good surgical option for treating DLSS.

Intraoperative neuromonitoring in spine surgery: large database analysis of cost-effectiveness

BACKGROUND

Given the increased attention to functional improvement in spine surgery as it relates to activities of daily living and cost, it is critical to fully understand the health care economic impact of enabling technologies. The use of intraoperative neuromonitoring (IOM) during spine surgery has long been controversial. Questions pertaining to utility, medico-legal considerations, and cost-effectiveness continue to be unresolved. The purpose of this study is to determine the cost-effectiveness by assessing quality-of-life due to adverse events averted, decreased postoperative pain, decreased revision rates, and improved patient reported outcomes (PROs).

METHODS

The study patient population was extracted from a large multicenter database collected by a single, national IOM provider. Over 50,000 patient charts were abstracted and included in this analysis. The analysis was conducted in accordance with the second panel on cost-effectiveness health and medicine. Health-related utility was derived from questionnaire answers and expressed in quality-adjusted life years (QALYs). Both cost and QALY outcomes were discounted at a yearly rate of 3% to reflect their present value. Cost-effectiveness was calculated as the incremental cost-effectiveness ratio (ICER) for IOM. A value under the commonly accepted United States-based willingness-to-pay (WTP) threshold of $100,000 per QALY was considered cost-effective. Scenario (including litigation), probabilistic (PSA), and threshold sensitivity analyses were conducted to determine model discrimination and calibration.

RESULTS

The primary time horizon used to estimate cost and health utility was 2-years following index surgery. On average, index surgery for patients with IOM costs are approximately $1,547 greater than non-IOM cases. The base case assumed an inpatient Medicare population however multiple outpatient and payer scenarios were assessed in the sensitivity analysis. From a health system perspective IOM is cost-effective, yielding better utilities but at a higher cost than the non-IOM strategy (ICER $60,734 per QALY). From a societal perspective the IOM strategy was dominant, suggesting that better outcomes were achieved at less cost. Except for an entirely privately insured population, alternative scenarios such as, outpatient and a 50:50 Medicare/privately insured population sample also demonstrated cost-effectiveness. Notably, IOM benefits were unable to overcome the sheer costs associated many litigation scenarios, but the data was severely limited. In the 5,000 iteration PSA, at a WTP of $100,000, 74% of simulations using IOM were cost-effective.

CONCLUSIONS

The use of IOM in spine surgery is cost-effective in most scenarios examined. In the emerging and rapidly expanding field of value-based medicine, there will be an increased demand for these analyses, ensuring surgeons are empowered to make the best, most sustainable solutions for their patients and the health care system.

Less-invasive decompression procedures can reduce risk of reoperation for lumbar spinal stenosis with diffuse idiopathic skeletal hyperostosis extended to the lumbar segment: analysis of two retrospective cohorts

PURPOSE

Clinical outcomes after decompression procedures are reportedly worse for lumbar spinal stenosis (LSS) with diffuse idiopathic skeletal hyperostosis (DISH), especially DISH extended to the lumbar segment (L-DISH). However, no studies have compared the effect of less-invasive surgery versus conventional decompression techniques for LSS with DISH. The purpose of this study was to compare the long-term risk of reoperation after decompression surgery focusing on LSS with L-DISH.

METHODS

This study compared open procedure cohort (open conventional fenestration) and less-invasive procedure cohort (bilateral decompression via a unilateral approach) with ≥ 5 years of follow-up. After stratified analysis by L-DISH, patients with L-DISH were propensity score-matched by age and sex.

RESULTS

There were 57 patients with L-DISH among 489 patients in the open procedure cohort and 41 patients with L-DISH among 297 patients in the less-invasive procedure cohort. The reoperation rates in L-DISH were higher in the open than less-invasive procedure cohort for overall reoperations (25% and 7%, p = 0.026) and reoperations at index levels (18% and 5%, p = 0.059). Propensity score-matched analysis in L-DISH demonstrated that open procedures were significantly associated with increased overall reoperations (hazard ratio [HR], 6.18; 95% confidence interval [CI], 1.37-27.93) and reoperations at index levels (HR, 4.80; 95% CI, 1.04-22.23); there was no difference in reoperation at other lumbar levels.

CONCLUSIONS

Less-invasive procedures had a lower risk of reoperation, especially at index levels for LSS with L-DISH. Preserving midline-lumbar posterior elements could be desirable as a decompression procedure for LSS with L-DISH.

Japanese Orthopaedic Association (JOA) clinical practice guidelines on the management of lumbar spinal stenosis, 2021 - Secondary publication

BACKGROUND

The Japanese Orthopaedic Association (JOA) guideline for the management of lumbar spinal stenosis (LSS) was first published in 2011. Since then, the medical care system for LSS has changed and many new articles regarding the epidemiology and diagnostics of LSS, conservative treatments such as new pharmacotherapy and physical therapy, and surgical treatments including minimally invasive surgery have been published. In addition, various issues need to be examined, such as verification of patient-reported outcome measures, and the economic effect of revised medical management of patients with lumbar spinal disorders. Accordingly, in 2019 the JOA clinical guidelines committee decided to update the guideline and consequently established a formulation committee. The purpose of this study was to describe the formulation we implemented for the revision of the guideline, incorporating the recent advances of evidence-based medicine.

METHODS

The JOA LSS guideline formulation committee revised the previous guideline based on the method for preparing clinical guidelines in Japan proposed by the Medical Information Network Distribution Service in 2017. Background and clinical questions were determined followed by a literature search related to each question. Appropriate articles based on keywords were selected from all the searched literature. Using prepared structured abstracts, systematic reviews and meta-analyses were performed. The strength of evidence and recommendations for each clinical question was decided by the committee members.

RESULTS

Eight background and 15 clinical questions were determined. Answers and explanations were described for the background questions. For each clinical question, the strength of evidence and the recommendation were both decided, and an explanation was provided.

CONCLUSIONS

The 2021 clinical practice guideline for the management of LSS was completed according to the latest evidence-based medicine. We expect that this guideline will be useful for all medical providers as an index in daily medical care, as well as for patients with LSS.

Additional operation rates after surgery for degenerative spine diseases: minimum 10 years follow-up of 4705 patients in the national Swedish spine register

OBJECTIVES

To identify rates of additional operation after the index operation for degenerative lumbar spine diseases.

DESIGN

Retrospective register study.

SETTING

National outcome data from Swespine, the National Swedish spine register.

PARTICIPANTS

A total of 4705 patients who underwent one-level surgery for degenerative disk disease (DDD) or lumbar spinal stenosis (LSS) with or without degenerative spondylolisthesis (DS) between 1 January 2007 and 31 December 2010 were followed from 1 January 2007 to 31 December 2020 to record all cases of additional lumbar spine operations.

INTERVENTIONS

One-level spinal decompression and/or posterolateral fusion for degenerative spine diseases.

PRIMARY OUTCOME MEASURES

Number of additional operations.

RESULTS

Additional operations were more common at adjacent levels for patients with LSS with DS treated with decompression and fusion whereas additional operations were more evenly distributed between the index level and the adjacent levels for DDD treated with fusion and LSS with and without DS treated with decompression only. For patients younger than 60 years, treated with decompression and fusion for LSS with DS, the additional operations were evenly distributed between the index level and the adjacent levels.

CONCLUSIONS

There are different patterns of additional operations following the index procedure after surgery for degenerative spine diseases. Rigidity across previously mobile segments is not the only important factor in the development of adjacent segment disease (ASD) after spinal fusion, also the underlying disease and age may play parts in ASD development. The findings of this study can be used in the shared decision-making process when surgery is a treatment option for patients with degenerative lumbar spine diseases as the first operation may be the start of a series of additional spinal operations for other degenerative spinal conditions, either at the index level or at other spinal levels.

Rates of Future Lumbar Fusion in Patients with Cauda Equina Syndrome Treated With Decompression

INTRODUCTION

The long-term risk of conversion to lumbar fusion is ill-defined for patients with cauda equina syndrome (CES) treated with decompression. This study aimed to identify the rates of fusion in patients with CES and compare those rates with a matched lumbar spinal stenosis (LSS) group.

METHODS

Patients with CES who underwent decompression were identified in a national database and matched to control patients with LSS. The rates of conversion to fusion were identified and compared. Multivariate logistic regression analysis identified independently associated risk factors. A subanalysis was conducted after stratifying by timing between CES diagnosis and decompression.

RESULTS

The rate of lumbar fusion in the CES cohort was 3.6% after 1 year, 6.7% after 3 years, and 7.8% after 5 years, significantly higher than the LSS control group at all time points (1 year: 1.6%, P = 0.001; 3 years: 3.0%, P &lt; 0.001; 5 years: 3.8%, P &lt; 0.001). CES was independently associated with increased risk of conversion to fusion (odds ratio: 2.13; 95% confidence interval: 1.56 to 2.97; P &lt; 0.001). Surgical timing was not associated with risk of conversion to fusion.

CONCLUSIONS

After 5 years, 7.8% of patients with CES underwent fusion, a markedly higher rate compared with patients with LSS. Counseling patients with CES on this increased risk of future surgery is important for patient education and satisfaction.

Reoperation and Mortality Rates Following Elective 1 to 2 Level Lumbar Fusion: A Large State Database Analysis

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

Reoperation to lumbar spinal fusion creates significant burden on patient quality of life and healthcare costs. We assessed rates, etiologies, and risk factors for reoperation following elective 1 to 2 level lumbar fusion.

METHODS

Patients undergoing elective 1 to 2 level lumbar fusion were identified using the Health Care Utilization Project (HCUP) state inpatient databases from Florida and California. Patients were tracked for 5 years for any subsequent lumbar fusion. Cox proportional hazard analyses for reoperation were assessed using the following covariates: fusion approach type, age, race, Charlson comormidity index, gender, and length of stay. Distribution of etiologies for reoperation was then assessed.

RESULTS

71, 456 patients receiving elective 1 to 2 level lumbar fusion were included. A 5-year reoperation rate of 13.53% and mortality rate of 2.22% was seen. Combined anterior-posterior approaches (HR = 0.904, p < 0.05) and TLIF (HR = 0.867, p < 0.001) were associated with reduced risk of reoperation compared to stand-alone anterior approaches and non-TLIF posterior approaches. Age, gender, and number of comorbidities were not associated with risk of reoperation. From 1 to 5 years, degenerative disease rose from 43.50% to 50.31% of reoperations; mechanical failure decreased from 37.65% to 29.77%.

CONCLUSIONS

TLIF and combined anterior-posterior approaches for 1 to 2 level lumbar fusion are associated with the lowest rate of reoperation. Number of comorbidities and age are not predictive of reoperation. Primary etiologies leading to reoperation were degenerative disease and mechanical failure. Mortality rate is not increased from baseline following 1 to 2 level lumbar fusion.

Incidence of Revision Surgery After Decompression With vs Without Fusion Among Patients With Degenerative Lumbar Spinal Stenosis

IMPORTANCE

Only limited data derived from large prospective cohort studies exist on the incidence of revision surgery among patients who undergo operations for degenerative lumbar spinal stenosis (DLSS).

OBJECTIVE

To assess the cumulative incidence of revision surgery after 2 types of index operations-decompression alone or decompression with fusion-among patients with DLSS.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study analyzed data from a multicenter, prospective cohort study, the Lumbar Stenosis Outcome Study, which included patients aged 50 years or older with DLSS at 8 spine surgery and rheumatology units in Switzerland between December 2010 and December 2015. The follow-up period was 3 years. Data for this study were analyzed between October and November 2021.

EXPOSURES

All patients underwent either decompression surgery alone or decompression with fusion surgery for DLSS.

MAIN OUTCOMES AND MEASURES

The primary outcome was the cumulative incidence of revision operations. Secondary outcomes included changes in the following patient-reported outcome measures: Spinal Stenosis Measure (SSM) symptom severity (higher scores indicate more pain) and physical function (higher scores indicate more disability) subscale scores and the EuroQol Health-Related Quality of Life 5-Dimension 3-Level questionnaire (EQ-5D-3L) summary index score (lower scores indicate worse quality of life).

RESULTS

A total of 328 patients (165 [50.3%] men; median age, 73.0 years [IQR, 66.0-78.0 years]) were included in the analysis. Of these, 256 (78.0%) underwent decompression alone and 72 (22.0%) underwent decompression with fusion. The cumulative incidence of revisions after 3 years of follow-up was 11.3% (95% CI, 7.4%-15.1%) for the decompression alone group and 13.9% (95% CI, 5.5%-21.5%) for the fusion group (log-rank P = .60). There was no significant difference in the need for revision between the 2 groups over time (unadjusted absolute risk difference, 2.6% [95% CI, -6.3% to 11.4%]; adjusted absolute risk difference, 3.9% [95% CI, -5.2% to 17.0%]; adjusted hazard ratio, 1.40 [95% CI, 0.63-3.13]). The number of revisions was significantly associated with higher SSM symptom severity scores (β, 0.171; 95% CI, 0.047-0.295; P = .007) and lower EQ-5D-3L summary index scores (β, -0.061; 95% CI, -0.105 to -0.017; P = .007) but not with higher SSM physical function scores (β, 0.068; 95% CI, -0.036 to 0.172; P = .20). The type of index operation was not significantly associated with the corresponding outcomes.

CONCLUSIONS AND RELEVANCE

This cohort study showed no significant association between the type of index operation for DLSS-decompression alone or fusion-and the need for revision surgery or the outcomes of pain, disability, and quality of life among patients after 3 years. Number of revision operations was associated with more pain and worse quality of life.

Study on the efficacy and safety of the combination of Shi's manual therapy and percutaneous endoscopic lumbar diskectomy for lumbar disc herniation with radiculopathy: study protocol for a multicenter randomized controlled trial

Background

Lumbar disc herniation (LDH) is a common chronic musculoskeletal disorder that seriously affects quality of life. The percutaneous endoscopic lumbar diskectomy (PELD) technique was developed to address spinal nerve root compression through direct visualization of pathological findings while minimizing tissue destruction upon exposure. It is an effective and safe treatment for LDH. However, recurrent LDH is a major concern after lumbar discectomy for primary LDH. A considerable number of clinical studies have reported that patients with LDH with radiculopathy could benefit from manual therapy. Shi’s manual therapy (SMT) was established based on traditional Chinese medicine (TCM) theory and has been shown to have a superior effect in alleviating muscle tension and loosening joints to improve lumbar and leg pain, radiculopathy, stiffness, activity discomfort, and related disorders. However, there is a lack of high-quality clinical evidence to support this conclusion. The purpose of this study is to evaluate the efficacy and safety of the combination of Shi’s manual therapy (SMT) and PELD for LDH with radiculopathy.

Methods/design

A multicenter randomized controlled trial (RCT) with a 1-year follow-up period will be performed. A total of 510 participants with LDH with radiculopathy will be recruited from four clinical centers. The sample size was estimated, and statistical analysis will be performed and supervised by biostatisticians from an independent third-party research institution. Two hundred fifty-five subjects will be randomly allocated to each group. The subjects in the control group will undergo PELD. Participants in the intervention group will be treated with a combination of SMT and PELD. Recurrence rate is the primary endpoint and the survival analysis of recurrence rate is the secondary endpoint, and the primary analysis of recurrence rate is the chi-square test and the secondary analysis of recurrence rate is survival analysis. The primary outcome measure is the recurrence rate of LDH with radiculopathy at the 1-year follow-up after treatment. The secondary outcome measures will be the ODI score, the VAS score for pain for the lumbar spine and lower limbs, the straight leg raise angle, the stability of the operated lumbar segment, and the SF-36 scores. Assessments will occur at baseline, postoperation, and 1 week, 4 weeks, 13 weeks, 26 weeks, and 1 year postoperation. In addition, adverse events related to clinical symptoms and signs and the results of laboratory tests will be documented during the clinical trials.

Discussion

This study will provide reliable evidence of the effectiveness and safety of the combination of SMT and PELD for LDH with radiculopathy. If the results are favorable, it is expected that patients with LDH with radiculopathy will benefit from this study, and many patients could gain a good alternative treatment for LDH with radiculopathy.

Trial registration

China Registered Clinical Trial Registration Center ChiCTR2000036515. Registered on 13 November 2020.

Risk Factors for Reoperation at Same Level after Decompression Surgery for Lumbar Spinal Stenosis in Patients with Diffuse Idiopathic Skeletal Hyperostosis Extended to the Lumbar Segments

Introduction

Diffuse idiopathic skeletal hyperostosis (DISH) extended to the lumbar segments (L-DISH) reportedly has adverse effects on the surgical outcomes of lumbar spinal stenosis (LSS). However, the risk factors in patients with L-DISH have not been clarified. The purpose of this study was to investigate the long-term risk factors for reoperation at the same level after decompression surgery alone for LSS in patients with L-DISH in a retrospective cohort study.

Methods

A postoperative postal survey was sent to 1,150 consecutive patients who underwent decompression surgery alone for LSS from 2002 to 2010. Among all respondents, patients who exhibited L-DISH by preoperative total spine X-ray were included in this study. We investigated risk factors for reoperation at the same level as the initial surgery among various demographic and radiological parameters, including the lumbar ossification condition and computed tomography (CT) or magnetic resonance imaging findings.

Results

A total of 57 patients were analyzed. Reoperations at the same level as that of the index surgery were performed in 10 patients (17.5%) and at 11 levels within a mean of 9.2 years. Cox proportional hazard regression analysis indicated that the independent risk factors for reoperation were a sagittal rotation angle ≥10° (adjusted hazard ratio: 5.17) and facet opening on CT (adjusted hazard ratio: 4.82). Neither sagittal translation nor the ossification condition in the lumbar segments affected reoperations.

Conclusions

A sagittal rotation angle ≥10° and facet opening on preoperative CT were risk factors for reoperation at the same level as that of the index surgery in patients with L-DISH. The surgical strategy should be carefully considered in those patients.

Associated factors of patients with spinal stenosis who undergo reoperation after a posterior lumbar spinal fusion in a Hispanic-American population

PURPOSE

The aim of this study was to evaluate the associated factors of patients with LSS who undergo reoperation after a PLSF in a Hispanic-American population.

METHODS

A retrospective single-center review was performed from all non-age-related Hispanic-Americans with LSS who underwent one or two-level PLSF from 2008 to 2018. Baseline characteristics were analyzed between the reoperation and no-reoperation group using a bivariate and multivariate analyses.

RESULTS

Out of 425 patients who underwent PLSF, 38 patients underwent reoperation. At a two-year follow-up, the reoperation rate was 6.1% (26/425), mostly due to pseudoarthrosis (39.5%), recurrent stenosis (26.3%), new condition (15.8%), infection (10.5%), hematoma (5.3%), and dural tear (2.6%). Patients who underwent reoperation were more likely to have a preoperative history of epidural steroid injection (ESI) (OR 5.18, P = 0.009), four or more comorbidities (OR 2.69, P = 0.028), and operated only with a posterolateral fusion without intervertebral fusion (OR 2.15, P = 0.032). Finally, the multivariable analysis showed that ESI was the only independent associated factor in patients who underwent reoperation after a PLSF in our group.

CONCLUSION

Among this population who underwent surgery, a reoperation rate at two years of follow-up was less than ten percent. Our study did not find any associated factor inherent to Hispanic-Americans, as ethnic group, who were reoperated after LSS.

The influence of comorbidities on the treatment outcome in symptomatic lumbar spinal stenosis: A systematic review and meta-analysis

BACKGROUND

Lumbar spinal stenosis (LSS) affects mainly elderly patients. To this day, it is unclear whether comorbidities influence treatment success. The aim of this systematic review and meta-analysis was to assess the impact of comorbidities on the treatment effectiveness in symptomatic LSS.

METHODS

We conducted a systematic review and meta-analysis and reviewed prospective or retrospective studies from Medline, Embase, Cochrane Library and CINAHL from inception to May 2020, including adult patients with LSS undergoing surgical or conservative treatment. Main outcomes were satisfaction, functional and symptoms improvement, and adverse events (AE). Proportions of outcomes within two subgroups of a comorbidity were compared with risk ratio (RR) as summary measure. Availability of ≥3 studies for the same subgroup and outcome was required for meta-analysis.

RESULTS

Of 72 publications, 51 studies, mostly assessing surgery, there was no evidence reported that patients with comorbidities were less satisfied compared to patients without comorbidities (RR 1.06, 95% confidence interval (CI) 0.77 to 1.45, I 2 94%), but they had an increased risk for AE (RR 1.46, 95% CI 1.06 to 2.01, I 2 72%). A limited number of studies found no influence of comorbidities on functional and symptoms improvement. Older age did not affect satisfaction, symptoms and functional improvement, and AE (age >80 years RR 1.22, 95% CI 0.98 to 1.52, I 2 60%). Diabetes was associated with more AE (RR 1.72, 95% CI 1.19 to 2.47, I 2 58%).

CONCLUSION

In patients with LSS and comorbidities (in particular diabetes), a higher risk for AE should be considered in the treatment decision. Older age alone was not associated with an increased risk for AE, less functional and symptoms improvement, and less treatment satisfaction.

Clinical outcomes of MED and iLESSYS® Delta for the treatment of lumbar central spinal stenosis and lateral recess stenosis: A comparison study

Microendoscopic discectomy (MED) is an established procedure used to treat lumbar central spinal stenosis (LCSS) and lateral recess stenosis (LRS). The Interlaminar Endoscopic Surgical System iLESSYS^® Delta approach has been developed from the traditional interlaminar endoscopic technique for the treatment of LCSS and LRS. In the present study, MED was used as a reference to evaluate this newly developed approach. A total of 82 and 52 patients with radicular leg pain and/or neurogenic claudication symptoms were treated by spinal canal decompression using the MED or iLESSYS^® Delta approach, respectively. The clinical outcomes of the patients were analyzed using the Modified MacNab's criteria, visual analogue scale (VAS) leg pain score, VAS back pain score and the Oswestry Disability Index (ODI) score. Finally, the effectiveness of the decompression was evaluated on a cross-sectional area of the dural sac (CSAD) at the disc level. The incision length in the iLESSYS^® Delta group was significantly decreased compared with the MED group (P<0.05); however, the duration of the operation in the iLESSYS^® Delta group was significantly longer compared with the MED group (P<0.05). The VAS score of the back and ODI score in the iLESSYS^® Delta group were significantly decreased compared with the MED group at the 1-week follow-up (P<0.0125). The postoperative CSAD was also significantly increased in both groups compared with before the operation (P<0.05); however, there were no significant differences in the postoperative CSAD between the two groups. The good-to-excellent rates of the MED and iLESSYS^® Delta approach were 89.0 and 90.4%, respectively, whereas the complication rates of the MED and iLESSYS^® Delta system were 3.66 and 3.85% in the two groups, respectively. In conclusion, the iLESSYS^® Delta approach was identified to be comparable with the MED approach for treating LCSS and LRS, demonstrating both precise and limited decompression. In addition, the iLESSYS^® Delta approach may reduce the short-term back pain and promote faster recovery compared with the MED.

Degenerative Spondylolisthesis: When to Fuse and When Not to? A New Scoring System

STUDY DESIGN

A prospective cohort.

OBJECTIVE

The objective of this study was to develop a scoring system for lumbar degenerative spondylolisthesis (LDS) that would guide decision-making.

BACKGROUND

The management protocol for LDS has been under debate, with no guidelines. Most studies oversimplify LDS as a homogenous entity.

MATERIALS AND METHODS

A retrospective analysis of 131 patients who underwent surgery for LDS between July 2007 and October 2011 with a minimum follow-up of 3 years was carried out on the basis of clinical, radiologic, and technical factors. A scoring system was conceptualized. Clinical: back pain score-2, age younger than 70 years-1, high-demand activity-1. Radiologic: segmental kyphosis-1.5, segmental dynamic translation-1, disk height >50% of adjacent level-1, facet effusion-1, sagittal facet-orientation-1. Technical: feasibility to decompress without causing instability-1.5. Its reliability was ascertained by a univariate analysis. The benchmark was set at 5.5 according to the Youden Index. This was followed by a prospective study for reliability analysis between November 2011 and January 2017 of 52 patients who underwent stand-alone decompression in LDS with a minimum follow-up of 24 months. Outcomes were evaluated using the Oswestry Disability Index and the Visual Analog Scale. Interobserver variability was determined. None of the patients in the retrospective or prospective group had undergone any lumbar surgery previously.

RESULTS

The mean Oswestry Disability Index and Visual Analog Scale of both the groups in the retrospective and the stand-alone decompression groups in prospective studies showed significant improvement. The interobserver reliability was high, with a κ value of 0.847.

CONCLUSIONS

The proposed scoring system helps view LDS as a heterogenous condition and assists in tailoring treatment for individual patients. For a select subgroup of patients with LDS, minimally invasive decompression (unilateral laminotomy and bilateral decompression using a minimally invasive surgery tubular retractor system) without fusion is adequate.

LEVEL OF EVIDENCE

Level III.

Bilateral laminotomy through a unilateral approach (minimally invasive) versus open laminectomy for lumbar spinal stenosis

PURPOSE

To compare the outcomes of minimally invasive (MI) bilateral laminotomy via unilateral approach versus open laminectomy in the treatment of lumbar spinal stenosis (LSS).

MATERIALS AND METHODS

In this prospective study, 62 patients were treated for LSS and were assigned to one of two groups over a 6-month period. Group A comprised 37 patients that underwent MI bilateral laminotomy. Group B comprised 25 patients that underwent open laminectomy. Follow-up duration was 3 years. The primary outcomes were the visual analogue scale (VAS) pain outcome score for back and leg, the Oswestry Disability Index (ODI) and complications.

RESULTS

MI methods were superior in most primary outcomes compared to open laminectomy. VAS back pain outcome was reduced from close to 7 to 4 in both groups. VAS leg pain was reduced from 6.8 to 3.2 in MI group and from 8.7 to 3.5 in the open group (p > 0.05 between groups, p < 0.05 comparing pre- to post-operative back and leg pain). ODI improved from 56.5 to 13 and 58 to 24 in MI and open groups, respectively (p > 0.05 between groups, p < 0.05 comparing pre- to post-operative disability). Complication and revision rates were lower in the MI technique than open laminectomy (8 versus 56%, p < 0.05; 3 versus 12%, p > 0.05). Length of stay ranges were less in MI than open group (1-3 versus 7-30 days, p > 0.05).

CONCLUSIONS

Bilateral laminotomy through a unilateral approach (minimally invasive) and open laminectomy are both effective in improving pain and disability in LSS. MI procedures have an advantage in shorter hospital stays, sparing of more bony structures and lower complication rates. MI unilateral decompression is at least as good as laminectomy in the treatment of LSS.

Preoperative Predictors of Better Long-term Functional Ability and Decreased Pain Following LSS Surgery: A Prospective Observational Study with a 10-year Follow-up Period

STUDY DESIGN

A prospective observational 10-year follow-up study.

OBJECTIVE

This study aimed to examine preoperative predictors for better surgical outcomes in patients with lumbar spinal stenosis (LSS) 10 years after surgery.

SUMMARY OF BACKGROUND DATA

LSS is a leading cause of low back surgery in patients older than 65 years. Limited data are available for predictors of long-term surgical outcomes in patients with LSS.

METHODS

At the baseline, 102 patients with LSS underwent decompressive surgery, and 72 of the original study sample participated in a 10-year follow-up study. Study patients filled out a questionnaire preoperatively, and follow-up data were collected at 3 months, 6 months, 1 year, 2 years, 5 years, and 10 years postoperatively. Surgical outcomes were evaluated in terms of disability with the Oswestry Disability Index (ODI) and pain with the visual analog scale (VAS). Predictors in the models were nonsmoking status, absence of previous lumbar surgery, self-rated health, regular use of painkillers for symptom alleviation, and BMI. Statistical analyses included longitudinal associations, subgroup analyses, and cross-sectional analyses.

RESULTS

Using multivariate analysis, statistically significant predictors for lower ODI and VAS scores at 10 years were nonsmoking status, absence of previous lumbar surgery, better self-rated health, and regular use of painkillers for <12 months. Patients who smoked preoperatively or had previous lumbar surgery experienced more pain and disability at the 10-year follow-up.

CONCLUSION

These study results can enhance informed decision-making processes for patients considering surgical treatment for LSS by showing preoperative predictors for surgical outcomes up to 10 years after surgery. Smokers and patients with previous lumbar surgery showed a decline in surgical benefits after 5 years.

LEVEL OF EVIDENCE

3.

Patients With Persistent Low Back Pain and Nerve Root Involvement: To Operate, or Not to Operate, That Is the Question

STUDY DESIGN

Prospective cohort study.

OBJECTIVE

The aims of this study were to evaluate the outcome of surgical and nonsurgical treatment for patients with lumbar herniated disc (LHD) or lumbar spinal stenosis (LSS) after 2 years and to identify predictors for nonsuccess.

SUMMARY OF BACKGROUND DATA

Studies regarding the clinician's ability to identify patients with a poor prognosis are not in concurrence and further studies are warranted.

METHODS

This study included 390 patients with LHD or LSS referred for surgical evaluation after unsuccessful conservative treatment. Nonsuccess was defined as a Roland-Morris Disability score above 4 (0-23) or a Numeric Rating Scale back and leg pain score above 20 (0-60). Uni- and multivariate logistic regression analyses were used to investigate potential predictive factors including sociodemographic characteristics, history findings, levels of pain and disability, and magnetic resonance imaging findings.

RESULTS

Rates of nonsuccess at 2 years were approximately 30% in surgically treated patients with LHD, approximately about 60% in patients with LSS for disability, and 30% and 40%, respectively for pain. For the main outcome variable, disability, in the final multiple logistic regression model, nonsuccess after surgery was associated with male sex (odds ratio [OR] 2.04, 95% confidence interval [CI]: 1.02-4.11, P = 0.04), low level of education (OR 2.60, 95% CI: 1.28-5.29, P = 0.01), high pain intensity (OR 3.06, 95% CI: 1.51-6.21, P < 0.01), and widespread pain (OR 3.59, 95% CI: 1.36-9.46, P = 0.01).

CONCLUSION

The results indicate that the prognosis for patients referred for surgery with persistent LHD or LSS and unsuccessful conservative treatment is substantially better when surgery is performed as opposed to not performed. The predictive value of the variables male sex, low level of education, high pain intensity, and widespread pain location found in our study are partly in accordance with results of previous studies. Thus, our results warrant further investigation until firm conclusions can be made.

LEVEL OF EVIDENCE

3.

Multifidus muscle fatty infiltration as an index of dysfunction in patients with single-segment degenerative lumbar spinal stenosis: A case-control study based on propensity score matching

The multifidus muscle morphology and its relation to the function of patients with degenerative lumbar spinal stenosis (DLSS) remains unclear. This study aimed to investigate the multifidus muscle morphology in patients with DLSS and to determine its relations to the patients function. Sixty-two patients with single-segment DLSS at L4-5 and sixty control patients with non-spinal-derived low back pain were retrospectively enrolled and further matched based on propensity scores. The Oswestry Disability Index (ODI) and bodily pain using the Short-Form Health Survey were evaluated. The cross-sectional area (CSA), CSA of fatty free (CSAF), and fatty infiltration rate [FIR; i.e., (1- CSAF/CSA) × 100%] of the multifidus muscle were measured on magnetic resonance images using ImageJ software. Adjustment for confounders was performed using generalized linear models. The FIR at L5-S1 in controls was statistically significant but slightly less than the DLSS group. The between-groups difference was 5% (p < 0.001), and 2.8% (p = 0.036) in the complete and matching cohorts, respectively, after adjustment. Statistically significant differences were not observed in other multifidus muscle parameters between the groups. FIR > 20% at L5-S1 was independently associated with ODI ≥ 41 in patients with DLSS [Retaining demography as control block or not, Odds ratio (OR) = 8.4, p = 0.023; OR = 12.3, p = 0.030]. The multifidus muscle at L5-S1 demonstrated slightly greater fatty infiltration in patients with L4-5 single-segment DLSS than controls. Significant fatty infiltration in the multifidus muscle at L5-S1 may be correlated with poor function in patients with L4-5 single-segment DLSS.

Revision after spinal stenosis surgery

PURPOSE

To make a literature review on spinal stenosis recurrence after a first surgery and edit rules to avoid this complication.

METHODS

We conducted two separate PUBMED searches to evaluate the revision post-stenosis and degenerative scoliosis surgery using the terms: lumbar vertebrae/surgery, spinal stenosis, spine, scoliosis and reoperation. The resulting papers were categorized into three groups: (1) those that evaluated reoperation post-simple decompression; (2) those that evaluated spinal decompression and fusion for short (3 levels or less) or long (more than 3 levels) segment spinal fusion; and (3) those diagnosing the stenosis during the surgery.

RESULTS

(1) We found 11 relevant papers that only looked at revision spine surgery post-laminectomy for spinal stenosis. (2) We found 20 papers looked at reoperation post-laminectomy and fusion amongst which there were two papers specifically comparing long-segment (> 3 level) and short-segment (3 or less levels) fusions. (3) In the unspecified group, we found only one article. Fifteen articles were excluded as they were not specifically looking at our objective criteria for revision surgery. In regard to revision post-adult deformity surgery, we found 18 relevant articles.

CONCLUSIONS

After this literature review and analysis of post-operative stenosis, it seems important to provide some advice to avoid revision surgeries more or less induced by the surgery. It looks interesting when performing simple decompression without fusion in the lumbar spine to analyse the risk of instability induced by the decompression and facet resection but also by a global balance analysis. Regarding pre-operative stenosis in a previously operated area, different causes may be evocated, like screw or cage malpositionning but also insufficient decompression which is a common cause. Intraoperatively, the use of neuromonitoring and intraoperative CT scan with navigation are useful tool in complex cases to avoid persisting stenosis. Pre-op analysis and planning are key parameters to decrease post-op problems. These slides can be retrieved under Electronic Supplementary Material.

Psychological factors outmatched morphological markers in predicting limitations in activities of daily living and participation in patients with lumbar stenosis

BACKGROUND

Recent demographic changes have led to a large population of older adults, many of whom experience degenerative disc diseases. Degenerative lumbar spinal stenosis (DLSS) is associated with considerable discomfort and limitations in activities of daily living (ADL). Symptomatic DLSS is one of the most frequent indications for spinal surgery. The aim of this study was to identify sociodemographic variables, morphological markers, depression as well as fear of movement that predict ADL performance and participation in social life in patients with DLSS.

METHODS

Sixty-seven patients with DLSS (mean age 62.5 years [11.7], 50.7% females) participated in the study. Predictor variables were age, gender, duration of disease, three morphological markers (severity of the lumbar stenosis, the number of affected segments and presence of spondylolisthesis) as well as self-reported depression and fear of movement. Dependent variables were pain interference with the performance of ADLs, ADLs and participation in social life. Correlations between predictor and dependent variables were calculated before stepwise, linear regression analyses. Only significant correlations were included in the linear regression analyses.

RESULTS

Variance explained by the predictor variables ranged between 12% (R2 = .12; pain interference-physical) and 40% (R2 = .40; ADL requiring lower extremity functioning; participation). Depression and fear of movement were the most powerful predictors for all dependent variables. Among the morphological markers only stenosis severity contributed to the prediction of ADLs requiring lower extremity functioning.

CONCLUSION

Depression and fear of movement were more important predictors of the execution of ADLs and participation in social life compared to morphological markers. Elevated depressive symptoms and fear of movement might indicate limited adaptation and coping regarding the disease and its consequences. Early monitoring of these predictors should therefore be conducted in every spine centre. Future studies should investigate whether psychological screening or a preoperative psychological consultation helps to avoid operations and enables better patient outcomes.

A 5-Year Review of Hospital Costs and Reimbursement in the Surgical Management of Degenerative Spondylolisthesis

Background

To evaluate charges, expenses, reimbursement, and hospital margins with noninstrumented posterolateral fusion in situ (PLF), posterolateral fusion with pedicle screws (PPS), and PPS with interbody device (PLIF) in degenerative spondylolisthesis with spinal stenosis.

Methods

A retrospective chart review was performed from 2010 to 2014 based on ICD-9 diagnoses of degenerative spondylolisthesis with spinal stenosis in patients undergoing single-level fusions. All charges, expenses, reimbursement, and margins were obtained through financial auditing. A multivariate linear regression model was used to compare demographics, charges, etc. A 1-way analysis of variance with Tukey post hoc analysis was used to analyze reimbursements and margins based upon insurances.

Results

Two hundred thirty-three patients met inclusion criteria. The overall charges and expenses for PLF were significantly less compared to both types of instrumented fusions (P < .0001). Medicare and private insurance were the most common insurance types; Medicare and private insurance mean reimbursements for PLF were $36,903 and $47,086, respectively; for PPS, $37,450 and $53,851, and for PLIF $40,171 and $51,640. Hospital margins for PPS and PLIF in Medicaid patients were negative (-$3,702 and -$6,456). Hospital margins were largest for both worker's compensation and private insurance patients in all fusion groups. Hospital margins with Medicare for PLF, PPS, and PLIF were $24,347, $19,205, and $23,046, respectively. Hospital margins for private insurance for PLF, PPS, and PLIF were $37,569, $36,834, and $33,134, respectively.

Conclusions

As more instrumentation is used, the more it costs both the hospital and the insurance companies; hospital margins did not increase correspondingly.

Clinical Relevance

Improved understanding of related costs and margins associated with lumbar fusions to help transition to more cost effective spine centers.

Fat Infiltration in the Multifidus Muscle as a Predictor of Prognosis After Decompression and Fusion in Patients with Single-Segment Degenerative Lumbar Spinal Stenosis: An Ambispective Cohort Study Based on Propensity Score Matching

OBJECTIVE

To determine whether fat infiltration in the multifidus muscle would predict surgical prognosis in patients with degenerative lumbar spinal stenosis (DLSS).

METHODS

This ambispective cohort study enrolled 118 consecutive patients undergoing surgery for L4-5 single-segment DLSS. Fat infiltration rate (FIR) on magnetic resonance images of the multifidus muscle at L5-S1 were measured using ImageJ software. The enrolled patients were divided into FIR <25% and FIR ≥25% groups according to their FIR of the multifidus muscle at L5-S1. The 2 groups of patients who finished follow-up were further matched for the baseline covariates based on propensity scores. Patients' reported outcomes including the visual analog scale score for back pain and leg pain, and the Oswestry Disability Index (ODI) score were compared between groups at follow-up and further adjusted using generalized linear models.

RESULTS

Patients in the FIR <25% group showed statistically significantly greater reduction in ODI at 6 and 18 months after surgery than did patients in the FIR ≥25% group in either cohort regardless of adjustment; however, the 2-point between-group difference was smaller than the predefined minimum clinically important difference. In addition, more patients in the FIR <25% group achieved clinically significant improvement in ODI than those in the FIR ≥25% group in either complete cohort or matching cohort (63.8% vs. 21.1%, P < 0.001; 70.3% vs. 24.1%, P < 0.001, respectively) before and after adjustment (63.3% vs. 27.8%, P < 0.001; 69.1% vs. 31.0%, P < 0.001, respectively).

CONCLUSIONS

Fat infiltration in multifidus muscle at L5-S1 could be a potential predictor of functional improvement after surgery in patients with L4-5 single-segment DLSS.

Lumbar Spinal Stenosis and Degenerative Spondylolisthesis: A Review of the SPORT Literature

The Spine Patient-Reported Outcomes Related Trial (SPORT) is arguably one of the most impactful and insightful studies conducted in spine surgery. Designed as a prospective, multicenter study with randomized and observational cohorts, SPORT has provided vast data on the pathogenesis, treatment effects, clinical outcomes, cost effectiveness of disk herniation, lumbar spinal stenosis, and degenerative spondylolisthesis. With regards to spinal stenosis and degenerative spondylolisthesis, SPORT has demonstrated a sustained benefit from surgical intervention at 2, 4, and 8 years postoperatively. Myriad subgroup analyses have subsequently been performed that have also resulted in clinically relevant findings. These analyses have assessed incidence and risk factors for reoperations and intraoperative complications, impact of patient comorbidities and host factors, influence of epidural injections, patient decision-making, and role of nonoperative therapy. This has resulted in significant findings that may allow spine surgeons to optimize patient outcomes while managing expectations appropriately.

Reoperation Rate After Microsurgical Uni- or Bilateral Laminotomy for Lumbar Spinal Stenosis With and Without Low-grade Spondylolisthesis: What do Preoperative Radiographic Parameters Tell Us?

STUDY DESIGN

Retrospective single-center cohort study.

OBJECTIVE

The aim of this study was to analyze the influence of preoperative radiographic parameters on reoperation rates after microsurgical laminotomy for lumbar spinal stenosis (LSS).

SUMMARY OF BACKGROUND DATA

Decompression for symptomatic LSS has shown to be effective. However, the optimal surgical strategy remains a matter of debate, especially with underlying spondylolisthesis.

METHODS

Adult patients with LSS who underwent primary laminotomy without fusion between January 2012 and September 2013 at our institution were included for analysis. Disc height (in mm), facet joint (FJ) orientation (degrees), and grade of spondylolisthesis of all surgical index levels (SILs) were analyzed from preoperative magnetic resonance imaging. Patients were contacted in January 2017 by follow-up phone call (mean follow-up 49 months) regarding lumbar reoperation.

RESULTS

A total of 161 patients (mean age 68.5 yrs, ±11.3) and 236 SILs were analyzed. Fifty-six patients (34.8%) had low-grade spondylolisthesis involving 60 SILs (25.4%). Twenty-four patients (14.9%) underwent reoperation involving 32 levels. Of latter, 23 SILs (9.7%) had recurrent stenosis (RS) and 9 (3.8%) had adjacent level stenosis. Five patients in total (3.1%) required secondary fusion; all had preexisting spondylolisthesis. SILs with spondylolisthesis had a significantly higher rate of RS requiring reoperation compared with SILs without spondylolisthesis [18.3% (11/60) vs. 6.8% (12/176), P = 0.013]. Disc height and FJ orientation showed no significant difference between patients with and without reoperation, or with and without spondylolisthesis.

CONCLUSION

Decompression alone is reasonable for most patients with LSS and stable low-grade spondylolisthesis. The overall reoperation rate and need for secondary fusion were low in our series. However, patients with spondylolisthesis had a higher rate of reoperation for RS after laminotomy without fusion. This must be taken into account for preoperative risk-benefit analysis, tailored surgical decision making and patient counseling.

LEVEL OF EVIDENCE

4.

The influence of developmental spinal stenosis on the risk of re-operation on an adjacent segment after decompression-only surgery for lumbar spinal stenosis

Aims

The aim of this study was to determine the influence of developmental spinal stenosis (DSS) on the risk of re-operation at an adjacent level.

Patients and Methods

This was a retrospective study of 235 consecutive patients who had undergone decompression-only surgery for lumbar spinal stenosis and had a minimum five-year follow-up. There were 106 female patients (45.1%) and 129 male patients (54.9%), with a mean age at surgery of 66.8 years (sd 11.3). We excluded those with adult deformity and spondylolisthesis. Presenting symptoms, levels operated on initially and at re-operation were studied. MRI measurements included the anteroposterior diameter of the bony spinal canal, the degree of disc degeneration, and the thickness of the ligamentum flavum. DSS was defined by comparative measurements of the bony spinal canal. Risk factors for re-operation at the adjacent level were determined and included in a multivariate stepwise logistic regression for prediction modelling. Odds ratios (ORs) with 95% confidence intervals were calculated.

Results

Of the 235 patients, 21.7% required re-operation at an adjacent segment. Re-operation at an adjacent segment was associated with DSS (p = 0.026), the number of levels decompressed (p = 0.008), and age at surgery (p = 0.013). Multivariate regression model (p < 0.001) controlled for other confounders showed that DSS was a significant predictor of re-operation at an adjacent segment, with an adjusted OR of 3.93.

Conclusion

Patients with DSS who have undergone lumbar spinal decompression are 3.9 times more likely to undergo future surgery at an adjacent level. This is a poor prognostic indicator that can be identified prior to index decompression surgery.

Updated imaging does not affect revision rates in adults undergoing spine surgery for lumbar degenerative disease

OBJECTIVEDiagnostic workup for lumbar degenerative disc disease (DDD) includes imaging such as radiography, MRI, and/or CT myelography. If a patient has unsuccessful nonoperative treatment, the surgeon must then decide if obtaining updated images prior to surgery is warranted. The purpose of this study was to investigate whether the timing of preoperative neuroimaging altered clinical outcome, as reflected by the subsequent rate of revision surgery, in patients with degenerative lumbar spinal pathology.METHODSFrom the Health Care Service Corporation administrative claims database, adult patients (minimum age 55 years old) with lumbar DDD who underwent surgery including posterior lumbar decompression with and without fusion (1-2 levels) and at least 5 years of continuous coverage after the index surgery were identified. The chi-square test was used to determine differences in revision rates stratified by timing of each imaging procedure relative to the index procedure (< 6 months, 6-12 months, 12-24 months, or > 24 months).RESULTSOf 28,676 cases identified, 5128 (18%) had revision surgery within 5 years. The timing of preoperative MRI or plain radiography was not associated with revision surgery. Among the entire cohort, there was a lower incidence of revision surgery in patients who had a CT myelogram within 1 year prior to the index surgery (p = 0.017). This observation was strongest in patients undergoing decompression only (p = 0.002), but not significant in patients undergoing fusion (p = 0.845).CONCLUSIONSRoutine reimaging prior to surgery, simply because the existing MRI is 6-12 months old, may not be beneficial, at least as reflected in subsequent revision rates. The study also suggests that there may be a subset of patients for whom preoperative CT myelography reduces revision rates. This topic has important financial implications and deserves further study in a more granular data set.

Diffuse Idiopathic Skeletal Hyperostosis Extended to the Lumbar Segment Is a Risk Factor of Reoperation in Patients Treated Surgically for Lumbar Stenosis

STUDY DESIGN

Retrospective longitudinal cohort study.

OBJECTIVE

To investigate the association between diffuse idiopathic skeletal hyperostosis (DISH) and reoperation in patients treated surgically for lumbar spinal stenosis (LSS) in long-term results.

SUMMARY OF BACKGROUND DATA

Few studies have evaluated DISH as a potential risk factor of poor surgical results for LSS.

METHODS

This study included 1063 responders to a postoperative postal survey out of 2363 consecutive patients who underwent surgery for LSS between 2002 and 2010. The survey included questions about reoperations performed at another hospital and the patient-reported outcomes. DISH was evaluated by preoperative standing whole-spine radiographs. We investigated DISH as a predictor of reoperation and characteristics of poor outcomes in patients with DISH. We also assessed selection bias by examining the differences between responders and nonresponders to a postal survey.

RESULTS

Reoperations were performed in a total of 115 patients (10.8%) within an average of 8.6 years after the initial surgeries. Patients who only had DISH were not associated with reoperation; however, reoperations were performed significantly more often in patients with DISH extended to the lumbar segment (L-DISH) than in patients without (22% and 7.3%, respectively; P < 0.001). Cox analysis showed that L-DISH was one of the significant independent predictors for reoperation (hazard ratio 2.05, P = 0.009). Surgery-free survival was significantly shorter in patients with L-DISH than in those without (P = 0.005). The cause of reoperation did not differ between the patients with and without L-DISH. Several factors, but not L-DISH, were significantly associated with responders to the survey.

CONCLUSION

L-DISH was independently associated with reoperation for LSS. The decreased number of lumbar mobile segments due to L-DISH might lead to unfavorable outcomes. Careful follow-up of patients is needed after surgery for LSS with L-DISH.

LEVEL OF EVIDENCE

3.

Stability-preserving decompression in degenerative versus congenital spinal stenosis: demographic patterns and patient outcomes

BACKGROUND CONTEXT

Although lumbar spinal stenosis often presents as a degenerative condition (degenerative stenosis [DS]), some patients present with symptoms from lifelong narrowing of the spinal canal. These patients have congenital stenosis (CS) and present with symptoms of stenosis at a younger age. Patients with CS often have a distinct pathophysiology with fewer degenerative changes but present with multilevel involvement. In the setting of neurologic symptoms, decompression alone while preserving stability has been proposed for both patient populations.

PURPOSE

The purpose of this study is to evaluate if the different etiology for narrowing in CS and DS results in a different natural history of pain progression, different locations requiring decompression, and different outcomes following a stability-preserving decompression procedure.

STUDY DESIGN/SETTING

This study used a retrospective cohort study patient sample: We retrospectively reviewed consecutive patients of a single surgeon with DS or CS who underwent surgical decompression without fusion between 2008 and 2014. Patients were excluded if they had undergone a previous lumbar surgical procedure (decompression or fusion) or follow-up less than 12 months.

OUTCOME MEASURES

Pre- and postoperative clinical outcome scores including visual analogue scale (VAS) and Oswestry Disability Index (ODI) were recorded. Postoperatively, data were collected regarding complications, the presence of new radicular or myelopathic symptoms, and necessity of reoperation in the lumbar spine.

METHODS

Demographic information included age, sex, body mass index, smoking status, and Charleston Comorbidity Index (CCI). Preoperative clinical symptoms as well as the presence of lower extremity radiculopathy and claudication were evaluated. Patients were determined to have a diagnosis of CS by the treating surgeon if primary radiographs revealed shortened pedicles and decreased cross-sectional area of the spinal canal as detailed by previous studies. Binary outcomes were compared between congenital and degenerative cohorts using bivariate and multivariate logistic regression. Multivariate regressions controlled for baseline patient and operative characteristics.

RESULTS

The average age of the DS cohort was 66.7±10.7 years, whereas for the CS group, it was 47.1±9.2 years. Average follow-up was 27.6 months. The patients with DS had significantly more comorbidities as shown by the CCI score (2.8±1.6 vs. 0.5±0.6); p<.001) and the American Society of Anesthesiologists (ASA) score ≥3 (52.8% vs. 11.1%; p<.001). Patients with CS presented with higher VAS back (8.0 vs. 5.1; p=.008) and leg (7.9 vs. 4.5; p<.001) scores. Patients with DS presented with significantly greater duration of preoperative back pain and leg pain (42.7 vs. 30.5 months; p=.042). Postoperatively, there were no significant differences in VAS back, leg, or ODI scores. However, a trend toward a lower VAS leg score was present in the patients with CS when compared with patients with DS (2.6±3.0 vs. 4.2±3.2; p<.117). Both patient groups experienced similar levels of symptomatic relief and improvement in VAS and ODI scores. There were no significant differences in new-onset radicular symptoms requiring conservative treatment or reoperation. In both groups combined, 81.9% of patients reported resolution of lower extremity symptoms at final follow-up. Overall, 20.6% of patients experienced new lower-extremity radicular symptoms after a period of resolution of symptoms postoperatively. There were significantly more reoperations following surgical decompression in patients with DS (13.9% vs. 2.8%; p=.02).

CONCLUSIONS

Patients with CS and patients with DS respond well to decompression alone, without a supplemental fusion, despite differences in pain experience and presentation. The localization of pathology requiring decompression is similar. The patients with DS were more susceptible to require another operation resulting in a fusion, which confirms the theory that initial microinstability can progress in DS, but is likely not part of the disease process in CS. At just over 2 years after decompression, patients with CS may not need to be treated by a fusion in the setting of lower back pain; however, longer-term follow up is necessary to further assess these outcomes.

The Influence of Parkinson Disease on Lumbar Decompression Surgery: A Retrospective Case Control Study

BACKGROUND

Parkinson disease (PD) is a major risk factor during spine surgery, and its frequency is increasing as the population ages. The study aim was to examine the influence of PD specifically on lumbar decompression surgery.

METHODS

A retrospective review was performed of all patients with PD who underwent elective lumbar decompression surgery at 2 university hospital departments between December 2003 and July 2016. For each patient, 2 controls without PD were selected randomly among those who were matched for sex and age and had a similar year of surgery (±3) and comorbidity profile. The main outcomes were complications and reoperation rate.

RESULTS

The mean follow up was 1.2 ± 1.6 years in the PD group (n = 36) and 1.4 ± 2.1 years in the control group (n = 72). The overall complication rate was 47.2% in the PD group and 19.4% in the control group (P < 0.01). The reoperation rate was 27.8% in the PD group and 9.7% in the control group (P = 0.02).

CONCLUSIONS

There is a significantly greater rate of perioperative complications in patients with PD undergoing elective decompression surgery. Although the difference in major complication rates was minimal, minor complications were more frequent in patients with PD.

Adjacent Segment Disease in the Cervical and Lumbar Spine

Adjacent segment disease (ASD) is disappointing long-term outcome for both the patient and clinician. In contrast to adjacent segment degeneration, which is a common radiographic finding, ASD is less common. The incidence of ASD in both the cervical and lumbar spine is between 2% and 4% per year, and ASD is a significant contributor to reoperation rates after spinal arthrodesis. The etiology of ASD is multifactorial, stemming from existing spondylosis at adjacent levels, predisposed risk to degenerative changes, and altered biomechanical forces near a previous fusion site. Numerous studies have sought to identify both patient and surgical risk factors for ASD, but a consistent, sole predictor has yet to be found. Spinal arthroplasty techniques seek to preserve physiological biomechanics, thereby minimizing the risk of ASD, and long-term clinical outcome studies will help quantify its efficacy. Treatment strategies for ASD are initially nonoperative, provided a progressive neurological deficit is not present. The spine surgeon is afforded many surgical strategies once operative treatment is elected. The goal of this manuscript is to consider the etiologies of ASD, review its manifestations, and offer an approach to treatment.