Spine Instrumented Surgery on a Budget-Tools for Lowering Cost Without Changing Outcome

Social determinants of health and disparities in spine surgery: a 10-year analysis of 8,565 cases using ensemble machine learning and multilayer perceptron

BACKGROUND CONTEXT

The influence of SDOH on spine surgery is poorly understood. Historically, researchers commonly focused on the isolated influences of race, insurance status, or income on healthcare outcomes. However, analysis of SDOH is becoming increasingly more nuanced as viewing social factors in aggregate rather than individually may offer more precise estimates of the impact of SDOH on healthcare delivery.

PURPOSE

The aim of this study was to evaluate the effects of patient social history on length of stay (LOS) and readmission within 90 days following spine surgery using ensemble machine learning and multilayer perceptron.

STUDY DESIGN

Retrospective chart review.

PATIENT SAMPLE

8,565 elective and emergency spine surgery cases performed from 2013 to 2023 using our institution's database of longitudinally collected electronic medical record information.

OUTCOMES MEASURES

Patient LOS, discharge disposition, and rate of 90-day readmission.

METHODS

Ensemble machine learning and multilayer perceptron were employed to predict LOS and readmission within 90 days following spine surgery. All other subsequent statistical analysis was performed using SPSS version 28. To further assess correlations among variables, Pearson's correlation tests and multivariate linear regression models were constructed. Independent sample t-tests, paired sample t-tests, one-way analysis of variance (ANOVA) with post-hoc Bonferroni and Tukey corrections, and Pearson's chi-squared test were applied where appropriate for analysis of continuous and categorical variables.

RESULTS

Black patients demonstrated a greater LOS compared to white patients, but race and ethnicity were not significantly associated with 90-day readmission rates. Insured patients had a shorter LOS and lower readmission rates compared to non-insured patients, as did privately insured patients compared to publicly insured patients. Patients discharged home had lower LOS and lower readmission rates, compared to patients discharged to other facilities. Marriage decreased both LOS and readmission rates, underweight patients showcased increased LOS and readmission rates, and religion was shown to impact LOS and readmission rates. When utilizing patient social history, lab values, and medical history, machine learning determined the top 5 most-important variables for prediction of LOS -along with their respective feature importances-to be insurance status (0.166), religion (0.100), ICU status (0.093), antibiotic use (0.061), and case status: elective or urgent (0.055). The top 5 most-important variables for prediction of 90-day readmission-along with their respective feature importances-were insurance status (0.177), religion (0.123), discharge location (0.096), emergency case status (0.064), and history of diabetes (0.041).

CONCLUSIONS

This study highlights that SDOH is influential in determining patient length of stay, discharge disposition, and likelihood of readmission following spine surgery. Machine learning was utilized to accurately predict LOS and 90-day readmission with patient medical history, lab values, and social history, as well as social history alone.

Single-Center Experience of Resection of 120 Cases of Intradural Spinal Tumors

BACKGROUND

Our study presents a single-center experience of resection of intradural spinal tumors either with or without using intraoperative computed tomography-based registration and microscope-based augmented reality (AR). Microscope-based AR was recently described for improved orientation in the operative field in spine surgery, using superimposed images of segmented structures of interest in a two-dimensional or three-dimensional mode.

METHODS

All patients who underwent surgery for resection of intradural spinal tumors at our department were retrospectively included in the study. Clinical outcomes in terms of postoperative neurologic deficits and complications were evaluated, as well as neuroradiologic outcomes for tumor remnants and recurrence.

RESULTS

112 patients (57 female, 55 male; median age 55.8 ± 17.8 years) who underwent 120 surgeries for resection of intradural spinal tumors with the use of intraoperative neuromonitoring were included in the study, with a median follow-up of 39 ± 34.4 months. Nine patients died during the follow-up for reasons unrelated to surgery. The most common tumors were meningioma (n = 41), schwannoma (n = 37), myopapillary ependymomas (n = 12), ependymomas (n = 10), and others (20). Tumors were in the thoracic spine (n = 46), lumbar spine (n = 39), cervical spine (n = 32), lumbosacral spine (n = 1), thoracic and lumbar spine (n = 1), and 1 tumor in the cervical, thoracic, and lumbar spine. Four biopsies were performed, 10 partial resections, 13 subtotal resections, and 93 gross total resections. Laminectomy was the common approach. In 79 cases, patients experienced neurologic deficits before surgery, with ataxia and paraparesis as the most common ones. After surgery, 67 patients were unchanged, 49 improved and 4 worsened. Operative time, extent of resection, clinical outcome, and complication rate did not differ between the AR and non-AR groups. However, the use of AR improved orientation in the operative field by identification of important neurovascular structures.

CONCLUSIONS

High rates of gross total resection with favorable neurologic outcomes in most patients as well as low recurrence rates with comparable complication rates were noted in our single-center experience. AR improved intraoperative orientation and increased surgeons' comfort by enabling early identification of important anatomic structures; however, clinical and radiologic outcomes did not differ, when AR was not used.

Monthly multidisciplinary complex spine conference: a cost-analysis utilizing time-driven activity-based costing

PURPOSE

To understand costs and provide an initial framework associated with conference implementation as it pertains to complication prevention.

METHODS

Team members' time spent on conference preparation, presentation, and follow-up tasks was recorded and averaged to determine the time required to prepare and present one patient. Using 2022 hourly wage rates based on our urban hospital setting, wage values were calculated for each personnel type and applied to their time spent. The total cost of the conference was annualized and calculated from the time spent in the three phases of the conference multiplied by the wage rate. Published data on complication rates and associated costs before and after conference implementation were used to calculate total cost reduction.

RESULTS

With 3 active spine surgeons and 108 patients per year, the total time investment was 104.04 min per patient, costing $21,791 annually. Total RN equivalent value per patient was 5.25 for all three phases. Using a historical model, this multidisciplinary approach for adult spinal deformity reduced complications by 51% at 30 days, resulting in cost savings of $418,518 per year. Thus, the model demonstrates that implementation of this approach resulted in a potential total savings of $396,726/year.

CONCLUSION

Implementing a cost-saving tool for managing complex spinal disorders is a responsibility of the spine team, who should lead a multidisciplinary conference. The combination of TDABC and lean methodology can effectively demonstrate the variable costs associated with this multidisciplinary effort and models provide evidence of potential cost-savings when applied to a multidisciplinary adult spinal deformity conference. These findings should encourage clinicians and administrators to allocate resources to improve patient care by reducing complications and costs.

How much are patients willing to pay for spine surgery? An evaluation of attitudes toward out-of-pocket expenses and cost-reducing measures

BACKGROUND CONTEXT

With rising healthcare expenditures in the United States, patients and providers are searching to maintain quality while reducing costs.

PURPOSE

The aim of this study was to investigate patient willingness to pay for anterior cervical discectomy and fusion (ACDF), degenerative lumbar spinal fusions (LF), and adult spine deformity (ASD) surgery.

STUDY DESIGN/SETTING

A survey was developed and distributed to anonymous respondents through Amazon Mechanical Turk (MTurk).

METHODS

The survey introduced 3 procedures: ACDF, LF, and ASD surgery. Respondents were asked sequentially if they would pay at each increasing price option. Respondents were then presented with various cost-saving methods and asked to select the options that made them most uncomfortable, even if those would save them out-of-pocket costs.

RESULTS

In total, 979 of 1,172 total responses (84%) were retained for analysis. The average age was 36.2 years and 44% of participants reported a household income of $50,000 to 100,000. A total of 63% used Medicare and 13% used Medicaid. A total of 40% stated they had high levels of financial stress. A total of 30.1% of participants were willing to undergo an ACDF, 30.3% were willing to undergo a LF, and 29.6% were willing to undergo ASD surgery for the cost of $3,000 (p=.98). Regression demonstrated that for ACDF surgery, a $100 increase in price resulted in a 2.1% decrease in willingness to pay. This is comparable to degenerative LF surgery (1.8% decrease), and ASD surgery (2%). When asked which cost-saving measures participants were least comfortable with for ACDF surgery, 60% stated "Use of the older generation implants/devices" (LF: 51%, ASD: 60%,), 61% stated "Having the surgery performed at a community hospital instead of at a major academic center" (LF: 49%, ASD: 56%), and 55% stated "Administration of anesthesia by a nurse anesthetist" (LF: 48.01%, ASD: 55%). Conversely, 36% of ACDF patients were uncomfortable with a "Video/telephone postoperative visit" to cut costs (LF: 51%, ASD: 39%).

CONCLUSIONS

Patients are unwilling to contribute larger copays for adult spinal deformity correction than for ACDF and degenerative lumbar spine surgery, despite significantly higher procedural costs and case complexity/invasiveness. Patients were most uncomfortable forfeiting newer generation implants, receiving the operation at a community rather than an academic center, and receiving care by physician extenders. Conversely, patients were more willing to convert postoperative visits to telehealth and forgo neuromonitoring, indicating a potentially poor understanding of which cost-saving measures may be implemented without increasing the risk of complications.

Effect of Preoperative Marijuana on Patient Outcomes and Opioid Use after Lumbar Decompression

STUDY DESIGN

Retrospective Cohort Study.

OBJECTIVES

Our study aims to analyze the effect of preoperative marijuana use on outcomes and postoperative opioid use in patients who have undergone lumbar decompression without fusion.

METHODS

All patients >18 years of age who underwent lumbar decompression from 2017-2022 with documented preoperative marijuana use at our academic institution were retrospectively identified. A 3:1 propensity match incorporating demographics, procedure type, and levels decompressed was performed to compare preoperative marijuana users and non-users. 1-year preoperative and postoperative opioid consumption in milligrams of morphine equivalents and postoperative outcomes including readmissions, reoperations, and complications, were obtained. A multivariate regression model was performed to measure the effect of marijuana use on the likelihood of a spine reoperation.

RESULTS

Of the 340 included patients, 85 were preoperative marijuana users. There were no significant differences in medical complications, 90-day readmissions, or opioid consumption preoperatively or postoperatively (P > .05). We identified a trend towards patients who used marijuana having more reoperations for any cause (20.0% vs 11.37%, P = .067). Multivariate logistic regression analysis suggested that preoperative marijuana use was a significant predictor of all-spine reoperations (OR = 2.06, P = .036).

CONCLUSIONS

In lumbar decompression patients, preoperative marijuana use does not impact opioid consumption, readmissions, or medical complications, but is a significant predictor of future postoperative reoperations. Additional research is necessary to further explore the role of marijuana use in spine surgery.

Previous Emergency Department Admission Is Associated With Increased 90-Day Readmission Following Cervical Spine Surgery: Evidenced Using Propensity Score Matching

STUDY DESIGN

This was a retrospective case-control study.

OBJECTIVE

The objective of this study was to evaluate whether prior emergency department admission was associated with an increased risk for 90-day readmission following elective cervical spinal fusion.

SUMMARY OF BACKGROUND DATA

The incidence of cervical spine fusion reoperations has increased, necessitating the improvement of patient outcomes following surgery. Currently, there are no studies assessing the impact of emergency department visits before surgery on the risk of 90-day readmission following elective cervical spine surgery. This study aimed to fill this gap and identify a novel risk factor for readmission following elective cervical fusion.

METHODS

The 2016-2018 Nationwide Readmissions Database was queried for patients aged 18 years and older who underwent an elective cervical fusion. Prior emergency admissions were defined using the variable HCUP_ED in the Nationwide Readmissions Database database. Univariate analysis of patient demographic details, comorbidities, discharge disposition, and perioperative complication was evaluated using a χ 2 test followed by multivariate logistic regression.

RESULTS

In all, 2766 patients fit the inclusion criteria, and 18.62% of patients were readmitted within 90 days. Intraoperative complications, gastrointestinal complications, valvular, uncomplicated hypertension, peripheral vascular disorders, chronic obstructive pulmonary disease, cancer, and experiencing less than 3 Charlson comorbidities were identified as independent predictors of 90-day readmission. Patients with greater than 3 Charlson comorbidities (OR=0.04, 95% CI 0.01-0.12, P <0.001) and neurological complications (OR=0.29, 95% CI 0.10-0.86, P =0.026) had decreased odds for 90-day readmission. Importantly, previous emergency department visits within the calendar year before surgery were a new independent predictor of 90-day readmission (OR=9.74, 95% CI 6.86-13.83, P <0.001).

CONCLUSIONS

A positive association exists between emergency department admission history and 90-day readmission following elective cervical fusion. Screening cervical fusion patients for this history and optimizing outcomes in those patients may reduce 90-day readmission rates.

Does healthcare system device volume correlate with price paid for spinal implants: a cross-sectional analysis of a national purchasing database

OBJECTIVES

Amid continuously rising US healthcare costs, particularly for inpatient and surgical services, strategies to more effectively manage supply chain expenses are urgently necessary. Across industries, the 'economy of scale' principle indicates that larger purchasing volumes should correspond to lower prices due to 'bulk discounts'. Even as such advantages of scale have driven health system mergers in the USA, it is not clear whether they are being achieved, including for specialised products like surgical implants which may be more vulnerable to cost inefficiency. The objective of this observational cross-sectional study was to investigate whether purchasing volumes for spinal implants was correlated with price paid.

SETTING

USA.

PARTICIPANTS

Market data based on pricing levels for spine implants were reviewed from industry implant price databases. Filters were applied to narrow the sample to include comparable institutions based on procedural volume, patient characteristics and geographical considerations. Information on the attributes of 619 health systems representing 12 471 provider locations was derived from national databases and analytics platforms.

PRIMARY OUTCOME MEASURE

Institution-specific price index paid for spinal implants, normalised to the national average price point achieved.

RESULTS

A Spearman's correlation test indicated a weak relationship between purchasing volume and price index paid (ρ=-0.35, p<0.001). Multivariable linear regression adjusting for institutional characteristics including type of hospital, accountable care organisation status, payer-mix, geography, number of staffed beds, number of affiliated physicians and volume of patient throughput also did not exhibit a statistically significant relationship between purchasing volume and price index performance (p=0.085).

CONCLUSIONS

National supply chain data revealed that there was no significant relationship between purchasing volume and price paid by health systems for spinal implants. These findings suggest that factors other than purchasing or patient volume are responsible for setting prices paid by health systems to surgical vendors and/or larger healthcare systems are not negotiating in a way to consistently achieve optimal pricing.