Socioeconomic Effects on Lumbar Fusion Outcomes

Evaluation of fusion status in patients with minimum 1-year survival post-oncologic spinal fusion

BACKGROUND CONTEXT

Oncologic patients have significant medical comorbidities which may impact arthrodesis after spine surgery. Furthermore, there is a paucity of published data describing fusion rates, and arthrodesis quality.

PURPOSE

In this study, we present institutional data for patients with minimum 1-year survival who underwent spinal fusion secondary to treatment of metastatic spine disease.

STUDY DESIGN/SETTING

Retrospective cohort study done at a single tertiary medical center.

PATIENT SAMPLE

Patients were selected from a single institution between 2012 and 2022. Included patients had spinal fusion as part of oncologic treatment, minimum of 1 year follow up, and postoperative Computed Tomography (CT) scan at minimum 1 year.

OUTCOME MEASURES

Patient outcomes included fusion status and Hounsfield units (HU) on CT scan at 1 year.

METHODS

Retrospective chart review was performed collecting demographic and treatment information including postoperative oncologic and radiation treatment as well as HU along the cranial and caudal pedicles bilaterally on the 1-year CT scan. Indications for surgery included symptomatic metastatic disease. All surgeries were performed by 1 of 3 surgeons at a single tertiary medical center. Statistical analysis was performed using the Student T-Test and Chi-Squared Test.

RESULTS

There were 74 patients presenting with metastatic spine disease who met inclusion criteria. Demographics included an average age of 61.9 years at time of surgery, median construct length of 6 levels, and median survival was 43.2 months. Our cohort demonstrated complete and partial fusion rates of 11.1% and 59.5%, respectively. There was a significant difference in average HU for patients demonstrating fusion at 1 year, 444.2 compared to those demonstrating a lack of fusion, 285.8 (p<.0001). Patients who received postoperative radiation had higher postoperative HU than those who did not receive radiotherapy (411.1 vs. 304.9, p=.042). There was no significant difference in fusion status based on postoperative chemotherapy status, p=.127. Additionally, there was no difference in HU based on SBRT versus conventional radiotherapy, p=.588.

CONCLUSION

Partial fusion was seen in over half of the study cohort at 1-year follow-up; complete fusion was seen in 11% of patients. Fused patients and those who received postoperative chemotherapy had significantly higher HU on 1-year CT. Maximizing control of cancer burden as well as improving bone quality may help patients with metastatic spine disease demonstrate bony fusion. More research is indicated to evaluate causal implications of survival in patients with metastatic spine disease that have undergone spinal fusion.

Higher socioeconomic status is associated with greater rates of surgical resource utilization prior to spine fusion surgery

BACKGROUND CONTEXT

Previous research has demonstrated an association between socioeconomic status (SES) and patient health, specifically noting that patients of lower SES have poor health outcomes. Understanding how social factors, including socioeconomic status (SES), relate to disparities in health outcomes is critical to closing gaps in equitable care to patients. While several studies have examined the effect of SES on postoperative spine outcomes, there is limited spine literature evaluating SES in the context of barriers to spine care.

PURPOSE

The primary objective of this study was to determine if socioeconomic status is associated with resource utilization prior to spine surgery consultation. As part of a subanalysis, this paper also explores the effect of other social factors on previsit resource utilization.

STUDY DESIGN

Retrospective cohort study.

PATIENT SAMPLE

Adult patients who underwent elective cervical or lumbar spinal fusion between 2020 and 2021.

OUTCOME MEASURES

Previsit resource utilization including 1) epidural steroid injection, 2) opioid use, 3) physical therapy, 4) prior spine surgeon, and 5) prior spine surgery.

METHODS

Each patient was assigned a "distressed score" using the Distressed Communities Index (DCI) and a socioeconomic status (SES) score using the Social Vulnerability Index (SVI) based on their zip code. Patient charts were manually reviewed to collect data regarding previsit resource utilization. The cohort was analyzed based on DCI quintile and SVI quartile. Additional analyses were conducted based on marital status and race.

RESULTS

Our study included 996 patients in the final analysis. Based on DCI, patients from prosperous communities were more likely to have previously visited a spine surgeon (13.2% (prosperous) vs 7.58% vs 6.92% vs 9.09% vs 3.70% (distressed), p=.015) and to have had prior spine surgery (11.1% (prosperous) vs 9.57% vs 9.09% vs 2.52% vs 6.36% (distressed), p=.015). Similarly, when evaluated based on SES SVI, patients who lived in a low-risk community were more likely to have previously visited a spine surgeon (13.0% low-risk vs 7.26% low-medium risk vs 16.9% medium-high risk vs 10.6% high risk, p=.049) and to have had prior spine surgery (13.0% low-risk vs 7.26% vs 16.9% vs 10.6% high risk, p=.030). When evaluated based on marital status, there was no difference in any resource utilization. Non-Black and non-White patients were more likely to have tried physical therapy compared to their black and white counterparts (76.9% (other) vs 60.9% (Black) vs 54.3% (White), p=.026).

CONCLUSION

This study examined the relationship between socioeconomic status and resource utilization and found a positive correlation between higher social standing and access to spine surgery and spine surgeons. These findings demonstrate a propensity for earlier evaluation of spine-related conditions among patients from prosperous communities compared to patients from less prosperous communities.

The Effect of Community-Level Socioeconomic Status on Surgical Outcomes Following Revision Lumbar Fusion

BACKGROUND

The purpose of this study is to determine the impact of community-level socioeconomic status (SES) on surgical outcomes and patient-reported outcome measures (PROMs) following revision lumbar fusion.

METHODS

Adult patients who underwent revision lumbar fusion surgery from 2011-2021 were grouped by Distressed Community Index (DCI) into Prosperous, Comfortable, Mid-tier, and At-Risk/Distressed cohorts. Demographics, surgical information, and PROMs were compared based on DCI community status. Outcome measures were collected preoperatively, 3 months postoperatively, and 1 year postoperatively.

RESULTS

Eight hundred fifty three patients were included in the final cohort. There was no difference in terms of surgical approach or utilization of a staged procedure between the patient groups. Readmission (P = 0.752) and reoperation rates (P = 0.467) were similar across all community groups. Furthermore, for patients who required reoperation, the incision and drainage or revision surgery rate in each cohort was not statistically different (P = 0.902). Prosperous community patients reported significantly lower Visual Analog Scale Back pain preoperatively in comparison to patients from other DCI communities. All groups experienced a similar degree of postoperative improvement in Visual Analog Scale Back scores (P = 0.271). There were no other differences in preoperative or postoperative PROMs analyzed.

CONCLUSIONS

While there are socioeconomic differences based on DCI, community-level SES was not predictive of worse surgical outcomes following revision lumbar fusion. Patients from the most distressed communities were able to achieve similar improvement after revision surgery. This should encourage spine surgeons to feel comfortable discussing an indicated revision lumbar procedure with patients, and not view SES as a barrier to successful outcomes.

Comparative Analysis of Primary and Revision Single-Level Lumbar Fusion Surgeries: Predictors, Outcomes, and Clinical Implications Using Big Data

Background/Objectives: The etiology of lumbar spine revision surgery is multifactorial, involving mechanical, biological, and clinical factors that challenge sustained spinal stability. Comparative analysis reveals significantly higher complication rates, prolonged hospital stays, and increased costs for revision surgeries compared to primary fusions, despite low mortality rates. Leveraging a comprehensive dataset of 456,750 patients, this study identifies predictors of revision surgery and provides actionable insights to enhance patient outcomes and optimize healthcare resource allocation. Methods: A total of 456,750 patients registered in the National Inpatient Sample (NIS) database from 2016 to 2019 were identified as having undergone single-level lumbar fusion surgery (primary fusion: 99.5%; revision fusion: 0.5%). Multivariable logistic regression models adjusted for patient demographics, clinical comorbidities, and hospital characteristics were constructed to evaluate clinical outcomes and postoperative complications. Results: Patients undergoing revision lumbar fusion surgery were significantly younger compared to those undergoing primary fusion procedures (53.92 ± 20.65 vs. 61.87 ± 12.32 years, p < 0.001); among the entire cohort, 56.4% were women. Compared with patients undergoing primary lumbar fusion, those undergoing revision fusion surgery were significantly more likely to experience surgical site infections (odds ratio [OR] 27.10; 95% confidence interval [95% CI] 17.12-42.90; p < 0.001), urinary tract infections (OR 2.15; 95% CI 1.39-3.33; p < 0.001), and prolonged length of stay (OR 1.53; 95% CI 1.24-1.89; p < 0.001). Revision surgery patients had significantly lower odds of incurring high-end hospital charges (OR 0.65; 95% CI 0.51-0.83; p < 0.001). Other complications, including respiratory complications, dural tears, thromboembolic events, and acute renal failure, showed no statistically significant differences between the two groups. In-hospital mortality rates were low and did not differ significantly between groups (revision: 0.2% vs. primary: 0.1%, OR 3.29; 95% CI 0.45-23.84; p = 0.23). Conclusions: Patients undergoing revision lumbar fusion surgeries face significantly higher risks of surgical site infections, urinary tract infections, and prolonged hospital stays compared to primary fusion procedures. These findings highlight the need for targeted interventions to improve perioperative management and reduce complications in revision lumbar fusion surgery.

Association Between Median Household Income and Perioperative Outcomes of Lumbar Spinal Fusion: An Analysis of the National Inpatient Sample (2009-2020)

BACKGROUND

Relationships between low socioeconomic status and surgical outcomes are well established for certain procedures. However, scant literature has focused on relationships between median household income and lumbar fusion outcomes.

METHODS

Patients who underwent fusion procedures between January 1, 2009 and December 31, 2020 were identified from the National Inpatient Sample database. They were categorized into 4 quartiles, from lowest to highest, based on median household incomes in respective zip codes. We applied univariable and multivariable linear and logistic regression models to analyze perioperative data according to income quartiles.

RESULTS

We included 2,826,396 patients. In multivariable regression, patients in the 3 lowest income quartiles exhibited higher rates of in-hospital cardiac events perioperatively, with odds ratios (ORs) of 1.19 (95% confidence interval [CI]1.13-1.26, P < 0.001), 1.10 (95% CI 1.05-1.16, P < 0.001), and 1.06 (95% CI 1.01-1.12, P = 0.011) for the first, second, and third quartiles, respectively. Patients in the lowest income (first) quartile had a higher occurrence of perioperative urinary complications (OR = 1.07, 95% CI 1.03-1.12, P = 0.001), systemic infectious complications (OR = 1.17, 95% CI 1.04-1.32, P = 0.006), neurological deficit (OR = 1.17, 95% CI 1.06-1.30, P = 0.002), and wound infections (OR = 1.22, 95% CI 1.12-1.34, P < 0.001). Those in the 3 lowest income quartiles were less likely to experience respiratory, gastrointestinal, and venous thrombotic complications (P < 0.05). The lowest income quartile had protective associations for dural tears (OR 0.93, 95% CI 0.89-0.99, P = 0.038) and postprocedure anemia across all 3 lower quartiles, with OR < 1 and P < 0.001.

CONCLUSIONS

Reduced household income significantly affected perioperative outcomes after lumbar fusion and should be taken into consideration during the perioperative period.

Provider's exposure to diversity contributes to socioeconomic disparities in lumbar and cervical fusion outcomes

Background

Studies report patient race, income, and education influence spinal fusion outcomes; fewer studies, however, examine the influence of provider factors such as exposure to diversity or cultural sensitivity.

Objective

To examine how providers' experience with diverse patient populations affects spinal fusion outcomes.

Methods

Retrospective review of 39,680 patients undergoing lumbar and cervical fusions, 2003-2021, in Clinformatics® Data Mart national database. We used the provider patient racial diversity index (pRDI)-a published metric of physician exposure to diverse patients-to divide patients into groups based their provider's category (I, II, III) where patients treated by category III providers had surgeons with the most diverse patient populations. Multivariate regression models on propensity score-matched cohorts examined the association between patient SES and provider category on post-operative outcomes.

Results

Black patients had decreased discharge home (OR 0.67; 95% CI 0.54-0.83) compared to white patients. Patients treated by category III providers had increased length of stay (Coeff. 0.62; 95% CI 0.43-0.81), charge (Coeff. 36800; 95% CI 29,200-44,400), and decreased discharge home (OR 0.90; 95% CI 0.83-0.97) compared to patients treated by category I providers. Asian patients treated by category II providers had decreased readmission (OR 0.38; 95% CI 0.14-0.96), and Black patients treated by category III providers had increased discharge home (OR 1.41; 95% CI 1.1-1.9) compared to those treated by category I providers.

Conclusion

While our study found two specific instances of improved spine surgery outcomes for minority patients treated by providers serving diverse patient populations, we present mixed findings overall. This study serves as the foundation for future research to better understand how provider pRDI affects outcomes in patients undergoing lumbar and cervical spine surgery.

Risk analysis index predicts mortality and non-home discharge following posterior lumbar interbody fusion: a nationwide inpatient sample analysis of 429,380 patients (2019-2020)

PURPOSE

Frailty is an independent risk factor for adverse postoperative outcomes following spine surgery. The ability of the Risk Analysis Index (RAI) to predict adverse outcomes following posterior lumbar interbody fusion (PLIF) has not been studied extensively and may improve preoperative risk stratification.

METHODS

Patients undergoing PLIF were queried from Nationwide Inpatient Sample (NIS) (2019-2020). The relationship between RAI-measured preoperative frailty and primary outcomes (mortality, non-home discharge (NHD)) and secondary outcomes (extended length of stay (eLOS), complication rates) was assessed via multivariate analyses. The discriminatory accuracy of the RAI for primary outcomes was measured in area under the receiver operating characteristic (AUROC) curve analysis.

RESULTS

A total of 429,380 PLIF patients (mean age = 61y) were identified, with frailty cohorts stratified by standard RAI convention: 0-20 "robust" (R)(38.3%), 21-30 "normal" (N)(54.3%), 31-40 "frail" (F)(6.1%) and 41+ "very frail" (VF)(1.3%). The incidence of primary and secondary outcomes increased as frailty thresholds increased: mortality (R 0.1%, N 0.1%, F 0.4%, VF 1.3%; p < 0.001), NHD (R 6.5%, N 18.1%, F 36.9%, VF 42.0%; p < 0.001), eLOS (R 18.0%, N 21.9%, F 31.6%, VF 43.8%; p < 0.001) and complication rates (R 6.6%, N 8.8%, F 11.1%, VF 12.2%; p < 0.001). The RAI demonstrated acceptable discrimination for NHD (C-statistic: 0.706) and mortality (C-statistic: 0.676) in AUROC curve analysis.

CONCLUSION

Increasing RAI-measured frailty is significantly associated with increased NHD, eLOS, complication rates, and mortality following PLIF. The RAI demonstrates acceptable discrimination for predicting NHD and mortality, and may be used to improve frailty-based risk assessment for spine surgeons.

Fear of movement was associated with sedentary behaviour 12 months after lumbar fusion surgery in patients with low back pain and degenerative disc disorder

BACKGROUND

Movement behaviours, such as sedentary behaviour (SB) and moderate to vigorous physical activity (MVPA), are linked with multiple aspects of health and can be influenced by various pain-related psychological factors, such as fear of movement, pain catastrophising and self-efficacy for exercise. However, the relationships between these factors and postoperative SB and MVPA remain unclear in patients undergoing surgery for lumbar degenerative conditions. This study aimed to investigate the association between preoperative pain-related psychological factors and postoperative SB and MVPA in patients with low back pain (LBP) and degenerative disc disorder at 6 and 12 months after lumbar fusion surgery.

METHODS

Secondary data were collected from 118 patients (63 women and 55 men; mean age 46 years) who underwent lumbar fusion surgery in a randomised controlled trial. SB and MVPA were measured using the triaxial accelerometer ActiGraph GT3X+. Fear of movement, pain catastrophising and self-efficacy for exercise served as predictors. The association between these factors and the relative time spent in SB and MVPA 6 and 12 months after surgery was analysed via linear regression models, adjusting for potential confounders.

RESULTS

Preoperative fear of movement was significantly associated with relative time spent in SB at 6 and 12 months after surgery (β = 0.013, 95% confidence interval = 0.004 to 0.022, p = 0.007). Neither pain catastrophising nor self-efficacy for exercise showed significant associations with relative time spent in SB and MVPA at these time points.

CONCLUSIONS

Our study demonstrated that preoperative fear of movement was significantly associated with postoperative SB in patients with LBP and degenerative disc disorder. This finding underscores the potential benefits of preoperative screening for pain-related psychological factors, including fear of movement, preoperatively. Such screenings could aid in identifying patients who might benefit from targeted interventions to promote healthier postoperative movement behaviour and improved health outcomes.