The Influence of Body Mass Index on Functional Outcomes, Satisfaction, and Return to Work After Single-level Minimally-invasive Transforaminal Lumbar Interbody Fusion: A Five-year Follow-up Study

Impact of Obesity on Outcomes of Minimally Invasive Transforaminal Lumbar Interbody Fusion Surgeries: A Systematic Review and Meta-Analysis

OBJECTIVE

To evaluate the impact of obesity on various outcomes in patients undergoing minimally invasive transforaminal lumbar interbody fusion (TLIF) surgeries.

METHODS

PubMed, Scopus, Embase, and Cochrane Library databases were screened for studies reporting outcomes in obese and nonobese patients undergoing TLIF surgeries. Studies reporting operative time, estimated blood loss, length of hospital stay, incidence of pseudoarthrosis, Oswestry Disability Index (ODI) scores, pain scores (Visual Analog Scale, VAS), and PROMIS PF scores were included. A qualitative and quantitative analysis was performed to calculate mean differences or odds ratios (ORs) using random-effects models.

RESULTS

Fourteen good-quality studies were included in this review, with a combined sample size of 4,889 participants. The analysis revealed that patients with obesity had slightly longer operative times compared to patients with normal weight, with a mean difference of 14.87 minutes, though not significant. Similarly, morbidly obese patients had a mean difference of 21.44 minutes in operative time. Estimated blood loss was comparable in both groups. However, morbidly obese patients had longer hospital stays, with a mean difference of 8.18 days and obese patients have 20% higher odds of experiencing complications compared to nonobese patients. The incidence of pseudoarthrosis, ODI scores, or pain scores (VAS back and leg) were similar in obese and normal weight patients.

CONCLUSIONS

Obesity, particularly morbid obesity, may have an impact on certain outcomes in patients undergoing minimally invasive TLIF surgeries. Morbidly obese patients tend to have significantly longer operative times with significantly longer hospital stays than nonobese patients.

Development and Validation of a Nomogram to Predict the Risk of Recurrent Lower Extremity Radiating Pain Within 1 Week Following Full-Endoscopic Lumbar Discectomy

BACKGROUND

Accurately predicting the risk of lower extremity (LE) radiating pain after surgery is an important endeavor for spinal surgeons. Our study aimed to identify risk factors for LE radiating pain after decompression with full-endoscopic lumbar discectomy (FELD) and develop a nomogram.

METHODS

We retrospectively reviewed the medical data of patients with lumbar disc herniation who underwent FELD. Two hundred thirty-five patients diagnosed at our hospital from January 2015 to December 2020 were used for model development. The independent risk factors for LE radiating pain after surgery were determined by least absolute shrinkage and selection operator logistic regression and multivariate logistic regression analysis. A nomogram was developed to predict the risk of LE radiating pain based on independent risk factors. Receiver operating characteristic curve, calibration curve, and decision curve analyses were used to evaluate the predictive performance. The nomogram was further verified by an independent cohort.

RESULTS

Three hundred seventy-five patients were enrolled in this study, with 102 patients in the training cohort reporting LE radiating pain after FELD, while 133 patients did not. In the validation cohort, 57 patients reported LE radiating pain after FELD, while 83 patients did not. The model was established by multivariate logistic regression analysis. The risk factors included a higher Michigan State University classification of herniated discs, increased disease course, increased time of surgery, reduced lateral recess width, and an interlaminar surgical approach, compared to transforaminal approach. The C-indices and the area under the receiver operating characteristic curve of the predictive model demonstrated good discrimination. Good predictive performance and accuracy were also observed in the validation cohort.

CONCLUSIONS

A novel nomogram for predicting recurrent LE radiating pain within 1 week after FELD was established and validated. More aggressive pain management strategies should be considered for patients at high risk of LE radiating pain after surgery, as predicted by this model.

Minimally invasive versus open surgery for degenerative lumbar pathologies:a systematic review and meta-analysis

Introduction

With the increase in life expectancy and consequent aging of the population, degenerative lumbar spine diseases tend to increase its number exponentially. Several treatment options are available to treat degenerative spinal diseases, such as laminectomies, posterior fusions, and interbody fusions, depending on their locations, correction necessities, and surgeon philosophy. With the advance in technology and surgical knowledge, minimally invasive techniques (MIS) arose as a solution to reduce surgical morbidity, while maintaining the same benefits as the traditionally/open surgeries. Several studies investigated the possible advantages of MIS techniques against the traditional open procedures. However, those articles are usually focused only on one technique or on one pathology.

Methods

The electronic databases, including PubMed, Google Scholar, Ovid, and BVS, were systematically reviewed. Only original articles in English or Portuguese were added to the review, the revision was performed following the PRISMA guideline.

Results

Fifty-three studies were included in the meta-analysis. Of the studied outcomes the Length of Stay Odds of complications, Blood Loss, and Surgery costs presented significantly favored MIS approaches, while the Last FUP ODI score, and Surgery Time did not differ among the groups.

Conclusion

Minimally invasive techniques are a remarkably interesting option to traditional open surgeries, as these procedures showed a significant reduction in blood loss, hospitalization time, complications, and surgical costs.

Obesity and Spine Surgery: A Qualitative Review About Outcomes and Complications. Is It Time for New Perspectives on Future Researches?

STUDY DESIGN

Literature review.

OBJECTIVES

An increasing number of obese patients requires operative care for degenerative spinal disorders. The aim of this review is to analyze the available evidence regarding the role of obesity on outcomes after spine surgery. Peri-operative complications and clinical results are evaluated for both cervical and lumbar surgery. Furthermore, the contribution of MIS techniques for lumbar surgery to play a role in reducing risks has been analyzed.

METHODS

Only articles published in English in the last 10 years were reviewed. Inclusion criteria of the references were based on the scope of this review, according to PRISMA guidelines. Moreover, only paper analyzing obesity-related complications in spine surgery have been selected and thoroughly reviewed. Each article was classified according to its rating of evidence using the Sacket Grading System.

RESULTS

A total number of 1636 articles were found, but only 130 of them were considered to be relevant after thorough evaluation and according to PRISMA checklist. The majority of the included papers were classified according to the Sacket Grading System as Level 2 (Retrospective Studies).

CONCLUSION

Evidence suggest that obese patients could benefit from spine surgery and outcomes be satisfactory. A higher rate of peri-operative complications is reported among obese patients, especially in posterior approaches. The use of MIS techniques plays a key role in order to reduce surgical risks. Further studies should evaluate the role of multidisciplinary counseling between spine surgeons, nutritionists and bariatric surgeons, in order to plan proper weight loss before elective spine surgery.

Impact of Obesity Severity on Achieving a Minimum Clinically Important Difference Following Minimally Invasive Transforaminal Lumbar Interbody Fusion

STUDY DESIGN

This was a retrospective cohort study.

OBJECTIVE

The objective of this study was to determine the impact of obesity on postoperative outcomes and minimum clinically important difference (MCID) achievement following minimally invasive transforaminal lumbar interbody fusion (MIS TLIF).

SUMMARY OF BACKGROUND DATA

Obesity is a proven risk factor for poorer outcomes in MIS TLIF patients. However, few studies have investigated the impact of body mass index (BMI) on achievement of a MCID for Patient-Reported Outcome Measurement Information System Physical Function (PROMIS PF).

METHODS

A prospective surgical database was retrospectively reviewed for primary, elective, single level MIS TLIF patients. Patients were categorized into BMI groups: nonobese (<30 kg/m2); obese I (≥30 and <35 kg/m2); severe (≥35 and <40 kg/m2); and morbid (≥40 kg/m2). Demographic, perioperative information, and complication rates were compared between groups. Visual Analog Scale (VAS) back and leg, Oswestry Disability Index (ODI), 12-Item Short Form-12 Physical Composite Score (SF-12 PCS), and PROMIS PF were collected preoperatively and up to 2-year postoperatively. Impact of BMI on outcome measures and MCID achievement at all timepoints was evaluated.

RESULTS

A total of 162 patients were included with 88 patients categorized as normal weight, 37 obese I, 25 severe, and 12 morbid. SF-12 PCS, and PROMIS PF significantly differed by BMI at all timepoints, but only at 6- and 12-week for VAS back, preoperatively and 12 weeks for VAS leg, and preoperatively to 1-year for ODI. MCID achievement only differed for PROMIS PF and VAS back at 2 years, but did not for overall MCID achievement.

CONCLUSIONS

BMI is a significant predictor of ODI, SF-12 PCS, and PROMIS PF preoperatively to 1-year postoperatively, but only through 12-week for VAS scores. MCID achievement varied for PROMIS PF and VAS back, suggesting that though BMI may affect postoperative outcome values, obesity may impact a patient's perception of meaningful improvements in pain and physical function.

Does a high BMI affect the outcome of minimally invasive TLIF? A retrospective study of 207 patients

PURPOSE

We investigated whether a high Body Mass Index (BMI) affects the outcomes following Minimally Invasive TLIF (MI-TLIF) for degenerative lumbar pathologies.

METHODS

A retrospective study was undertaken to include patients operated between January 2016 and January 2020 with at least one-year follow-up. Various preoperative and demographic parameters were recorded and the patients were classified into normal, overweight and obese based on the BMI. The operative and outcome measures used for assessment were surgical time, blood loss, number of levels operated upon, skin incision length, day of independent mobilisation, total hospital stay including ICU stay, return to work and Visual Analogue Score (VAS) for back pain (VAS-BP) and leg pain (VAS-LP) and Oswestry Disability Index (ODI). Attainment of Minimal Clinically Important Difference (MCID) for the scores was calculated. Multivariate analyses were done to assess the effect of BMI on different parameters.

RESULTS

Blood loss and postoperative ICU stay were found to be higher in the obese patients. However, the other variables were comparable. VAS-BP, VAS-LP and ODI scores were significantly improved in all the patients with no inter-group variability. The MCID attainment was also similar. The satisfaction rating at 1-year and willingness for surgery again for similar disease was also similar. The overall complication rate was 14.9% and was comparable among the groups. Multivariate analyses revealed no significant association between BMI and various parameters.

CONCLUSION

In patients treated by MI-TLIF for degenerative lumbar spine pathology, BMI is not a factor that negatively affects the functional and clinical outcomes.

Comparative Demographics and Outcomes of Minimally Invasive Transforaminal Lumbar Interbody Fusion in Chinese, Malays, and Indians

STUDY DESIGN

This study carried out a retrospective review of prospectively collected registry data.

OBJECTIVE

This study aimed to determine whether (1) utilization rates; (2) demographics and preoperative statuses; and (3) clinical outcomes differ among Chinese, Malays, and Indians undergoing minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF).

SUMMARY OF BACKGROUND DATA

There is a marked racial disparity in spine surgery outcomes between white and African American patients. Comparative studies of ethnicity have mostly been carried out in American populations, with an underrepresentation of Asian ethnic groups. It is unclear whether these disparities exist among Chinese, Malays, and Indians.

METHODS

A prospectively maintained registry was reviewed for 753 patients who underwent primary MIS-TLIF for degenerative spondylolisthesis between 2006 and 2013. The cohort was stratified by race. Comparisons of demographics, functional outcomes, and patient satisfaction were performed preoperatively and 1 month, 3 months, 6 months, and 2 years postoperatively.

RESULTS

Compared with population statistics, there was an overrepresentation of Chinese (6.6%) and an underrepresentation of Malays (5.0%) and Indians (3.5%) who underwent MIS-TLIF. Malays and Indians were younger and had higher body mass index at the time of surgery compared with Chinese. After adjusting for age, sex, and body mass index, Malays had significantly worse back pain and Indians had poorer Short-Form 36 Physical Component Summary compared with Chinese preoperatively. Chinese also had a better preoperative Oswestry Disability Index compared with the other races. Although significant differences remained at 1 month, there was no difference in outcomes up to 2 years postoperatively, except for a lower Physical Component Summary in Indians compared with Chinese at 2 years. The rate of minimal clinically important difference attainment, satisfaction, and expectation fulfillment was also comparable. At 2 years, 87.0% of Chinese, 76.9% of Malays, and 91.7% of Indians were satisfied.

CONCLUSION

The variations in demographics, preoperative statuses, and postoperative outcomes between races should be considered when interpreting outcome studies of lumbar spine surgery in Asian populations.

LEVEL OF EVIDENCE

Level III-nonrandomized cohort study.

Impact of Obesity on Complication Rates, Clinical Outcomes, and Quality of Life after Minimally Invasive Transforaminal Lumbar Interbody Fusion

BACKGROUND

 Percutaneous pedicle screw fixation in obese patients remains a surgical challenge. We aimed to compare patient-reported outcomes and complication rates between obese and nonobese patients who were treated by minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF).

METHODS

 The authors retrospectively reviewed patients who underwent MIS-TLIF at a single institution between 2011 and 2014. Patients were classified as obese (body mass index [BMI] ≥30 kg/m²) or nonobese (BMI < 30 kg/m²), according to their BMI. Outcomes assessed were complications, numerical rating scale (NRS) scores for back and leg pain, Oswestry Disability Index (ODI), and 36-Item Short-Form Survey (SF-36) scores.

RESULTS

 The final study group consisted of 71 patients, 24 obese (33.8%, 34.8 ± 3.8 kg/m²) and 47 nonobese (66.2%, 25.4 ± 2.9 kg/m²). Instrumentation failures (13.6 vs. 17.0%), dural tears (17.2 vs. 4.0%), and revision rates (16.7 vs. 19.1%) were similar between both groups (p > 0.05). Perioperative improvements in back pain (4.3 vs. 5.4, p = 0.07), leg pain (3.8 vs. 4.2, p = 0.6), and ODI (13.3 vs. 22.5, p = 0.5) were comparable among the groups and persisted at long-term follow-up. Obese patients had worse postoperative physical component SF-36 scores than nonobese patients (36.4 vs. 42.7, p = 0.03), while the mental component scores were not statistically different (p = 0.09).

CONCLUSION

 Obese patients can achieve similar improvement of the pain intensity and functional status even at long-term follow-up. In patients with appropriate surgical indications, obesity should not be considered a contraindication for MIS-TLIF surgery.

Effects of preoperative obesity and psychiatric comorbidities on minimum clinically important differences for lumbar fusion in grade 1 degenerative spondylolisthesis: analysis from the prospective Quality Outcomes Database registry

OBJECTIVE

Medical comorbidities, particularly preoperatively diagnosed anxiety, depression, and obesity, may influence how patients perceive and measure clinical benefit after a surgical intervention. The current study was performed to define and compare the minimum clinically important difference (MCID) thresholds in patients with and without preoperative diagnoses of anxiety or depression and obesity who underwent spinal fusion for grade 1 degenerative spondylolisthesis.

METHODS

The Quality Outcomes Database (QOD) was queried for patients who underwent lumbar fusion for grade 1 degenerative spondylolisthesis during the period from January 2014 to August 2017. Collected patient-reported outcomes (PROs) included the Oswestry Disability Index (ODI), health status (EQ-5D), and numeric rating scale (NRS) scores for back pain (NRS-BP) and leg pain (NRS-LP). Both anchor-based and distribution-based methods for MCID calculation were employed.

RESULTS

Of 462 patients included in the prospective registry who underwent a decompression and fusion procedure, 356 patients (77.1%) had complete baseline and 12-month PRO data and were included in the study. The MCID values for ODI scores did not significantly differ in patients with and those without a preoperative diagnosis of obesity (20.58 and 20.69, respectively). In addition, the MCID values for ODI scores did not differ in patients with and without a preoperative diagnosis of anxiety or depression (24.72 and 22.56, respectively). Similarly, the threshold MCID values for NRS-BP, NRS-LP, and EQ-5D scores were not statistically different between all groups. Based on both anchor-based and distribution-based methods for determination of MCID thresholds, there were no statistically significant differences between all cohorts.

CONCLUSIONS

MCID thresholds were similar for ODI, EQ-5D, NRS-BP, and NRS-LP in patients with and without preoperative diagnoses of anxiety or depression and obesity undergoing spinal fusion for grade 1 degenerative spondylolisthesis. Preoperative clinical and shared decision-making may be improved by understanding that preoperative medical comorbidities may not affect the way patients experience and assess important clinical changes postoperatively.

Elderly Patients Undergoing Minimally Invasive Transforaminal Lumbar Interbody Fusion May Have Similar Clinical Outcomes, Perioperative Complications, and Fusion Rates As Their Younger Counterparts

BACKGROUND

Although several studies have suggested that minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) may be especially beneficial in the elderly population due to lower operative morbidity and faster postoperative recovery, there are limited studies investigating the functional outcomes, quality of life, and satisfaction in elderly patients after MIS-TLIF. Furthermore, existing studies had substantial clinical, diagnostic, and surgical heterogeneity.

QUESTIONS/PURPOSES

We asked if elderly patients could experience comparable (1) patient-reported pain, disability and quality of life, (2) perioperative complications, and (3) radiological fusion rates as their younger counterparts after MIS-TLIF.

METHODS

Prospectively collected registry data of patients undergoing primary, single-level, MIS-TLIF for degenerative spondylolisthesis between 2012 and 2014 were reviewed. We included 168 patients, 39 of whom were at least 70 years old. Of the 129 patients younger than 70 years old, propensity-score matching was used to select 39 younger controls with adjustment for sex, BMI, American Society of Anesthesiologists score, and baseline clinical outcomes. Perioperative complications and radiologic data were compared.

RESULTS

There was no difference in back pain (mean difference -0.3 [95% confidence interval -1.0 to 0.5]; p = 0.52); leg pain (mean difference -0.1 [95% CI to 0.6-0.5]; p = 0.85); Oswestry Disability Index (mean difference -2.9 [95% CI -8.0 to 2.2]; p = 0.26); and SF-36 physical (mean difference 3.0 [95% CI -0.7 to 6.8]; p = 0.107); and mental component summary (mean difference 1.9 [95% CI -4.5 to 8.2]; p = 0.56); up to 2 years postoperatively; 85% of younger patients and 85% of elderly patients were satisfied (p > 0.99) while 87% and 80%, respectively, had fulfilled expectations (p = 0.36). Four perioperative adverse events occurred in each group. There was also no difference in the rate of fusion (87% in younger patients and 90% in elderly patients; p = 0.135).

CONCLUSIONS

When clinical and surgical heterogeneity were minimized, elderly patients undergoing minimally invasive transforaminal lumbar interbody fusion not only had comparable rates of perioperative complications but also experienced similar improvements in pain, function, and quality of life. A high rate of satisfaction was achieved.

LEVEL OF EVIDENCE

Level II, prognostic study.