Geospatial Evaluation of Disparities in Access to Cervical Spine Fusion in Metropolitan Areas Across the United States

STUDY DESIGN

Retrospective study with epidemiologic analysis of public Medicare data.

OBJECTIVE

The purpose of this study is to use geospatial analysis to identify disparities in access to cervical spine fusions in metropolitan Medicare populations.

SUMMARY OF BACKGROUND DATA

Cervical spine fusion is among the most common elective procedures performed by spine surgeons and is the most common surgical intervention for degenerative cervical spine disease. Although some studies have examined demographic and socioeconomic trends in cervical spine fusion, few have attempted to identify where disparities exist and quantify them at a community level.

METHODS

Center for Medicare and Medicaid Services physician billing and Medicare demographic data sets from 2013 to 2020 were filtered to contain only cervical spine fusion procedures and then combined with US Census socioeconomic data. The Moran Index geospatial clustering algorithm was used to identify statistically significant hotspot and coldspots of cervical spine fusions per 100,000 Medicare members at a county level. Univariate and multivariate analysis was subsequently conducted to identify demographic and socioeconomic factors that are associated with access to care.

RESULTS

A total of 285,405 cervical spine fusions were analyzed. Hotspots of cervical spine fusion were located in the South, while coldspots were throughout the Northern Midwest, the Northeast, South Florida, and West Coast. The percent of Medicare patients that were Black was the largest negative predictor of cervical spine fusions per 100,000 Medicare members ( β =-0.13, 95% CI: -0.16, -0.10).

CONCLUSIONS

Barriers to access can have significant impacts on health outcomes, and these impacts can be disproportionately felt by marginalized groups. Accounting for socioeconomic disadvantage and geography, this analysis found the Black race to be a significant negative predictor of access to cervical spine fusions. Future studies are needed to further explore potential socioeconomic barriers that exist in access to specialized surgical care.

LEVEL OF EVIDENCE

Level III-retrospective.

Readability of Patient-Reported Outcomes in Spine Surgery and Implications for Health Literacy

STUDY DESIGN

Observational study.

OBJECTIVE

To evaluate the readability of commonly utilized patient-reported outcome measures (PROMs) in spine surgery.

SUMMARY OF BACKGROUND DATA

Although studies have evaluated patient education materials, discharge instructions, and informed consent forms in spine surgery, there is a dearth of literature on the readability of PROMs despite widespread health illiteracy. Without knowledge of PROM readability, it is unclear whether these measures are able to be understood by the average spine patient.

MATERIALS AND METHODS

We analyzed all commonly utilized nonvisual PROMs within the spinal literature and uploaded PROMs into an online readability calculator. The Flesch Reading Ease Score (FRES) and Simple Measure of Gobbledygook (SMOG) Index were collected. A FRES>79 or SMOG<7 was considered readable by the general population per American Medical Association and Centers for Disease Control guidelines. A stricter threshold recommended in health care (SMOG <6 or FRES>89) was then used to further review readability.

RESULTS

Seventy-seven PROMs were included. Based on FRES, the mean readability of all PROMs was 69.2 ± 17.2 (range, 10-96.4), indicating an average eighth to ninth-grade reading level. The mean readability score categorized by the SMOG Index was 8.12 ± 2.65 (range, 3.1-25.6), representing an eighth-grade reading level. Compared with the reading level of the general population, 49 (63.6%) PROMs are written above the United States literacy level, according to FRES. Using stricter definitions of readability, 8 PROMs were considered readable, including PROM Information System pain behavior (FRES: 96.4 and SMOG: 5.2), PROM Information System sleep disturbance (SMOG: 5.6), Neck Pain and Disability Scale (SMOG: 4.3), and Zung Depression Scale (SMOG: 3.1).

CONCLUSIONS

Most PROMs utilized in spine surgery require an average reading competency far above the average patient's comprehension. This may have a meaningful impact on understanding PROM instruments and may affect the accuracy of complete surveys and the rates of incompletion.

Reimbursement of Lumbar Fusion at an Orthopaedic Specialty Hospital Versus Tertiary Referral Center

STUDY DESIGN

Retrospective Cohort Study.

OBJECTIVE

To explore the differences in Medicare reimbursement for lumbar fusion performed at an orthopaedic specialty hospital (OSH) and a tertiary referral center and to elucidate drivers of Medicare reimbursement differences.

SUMMARY OF BACKGROUND DATA

To provide more cost-efficient care, appropriately selected patients are increasingly being transitioned to OSHs for lumbar fusion procedures. There are no studies directly comparing reimbursement of lumbar fusion between tertiary referral centers (TRC) and OSHs.

METHODS

Reimbursement data for a tertiary referral center and an orthopaedic specialty hospital were compiled through the Centers for Medicare and Medicaid Services. Any patient with lumbar fusions between January 2014 and December 2018 were identified. OSH patients were matched to TRC patients by demographic and surgical variables. Outcomes analyzed were reimbursement data, procedure data, 90-day complications and readmissions, operating room times, and length of stay (LOS).

RESULTS

A total of 114 patients were included in the final cohort. The tertiary referral center had higher post-trigger ($13,554 vs. $8,541, P <0.001) and total episode ($49,973 vs. $43,512, P <0.010) reimbursements. Lumbar fusion performed at an OSH was predictive of shorter OR time (β=0.77, P <0.001), shorter procedure time (β=0.71, P <0.001), and shorter LOS (β=0.53, P <0.001). There were no significant differences in complications (9.21% vs. 15.8%, P =0.353) or readmission rates (3.95% vs. 7.89%, P =0.374) between the 2 hospitals; however, our study is underpowered for complications and readmissions.

CONCLUSION

Lumbar fusion performed at an OSH, compared with a tertiary referral center, is associated with significant Medicare cost savings, shorter perioperative times, decreased LOS, and decreased utilization of post-acute resources.

LEVEL OF EVIDENCE

3.

Does Paraspinal Muscle Mass Predict Lumbar Lordosis before and after Decompression for Degenerative Spinal Stenosis?

STUDY DESIGN

Retrospective Cohort Study.

OBJECTIVE

The purpose of this study was to determine if muscle mass and quality of the lumbar paraspinal muscles was associated with improvements in lumbar lordosis and other sagittal parameters after isolated posterior lumbar decompression surgery for lumbar spinal stenosis.

SUMMARY OF BACKGROUND DATA

Over time, either due to degenerative changes or other spinal conditions, individuals may develop sagittal imbalance. In patients with lumbar spinal stenosis, sagittal imbalance can further exacerbate symptoms of pain and radiculopathy. Sarcopenia of paraspinal muscles has been implicated in previous spine research as a variable with influence on surgical outcomes.

METHODS

Sagittal parameters were measured on preoperative and postoperative lateral lumbar radiographs and included lumbar lordosis (LL), sacral slope (SS), and pelvic tilt (PT). Preoperative MRI images were evaluated at the base of the L4 vertebral body to assess muscles mass of the psoas muscle and paravertebral muscles (PVM) and Goutallier grade of the PVM. Patients were divided into 3 muscle size groups based on PVM normalized for body size (PVM/BMI): Group A (smallest), Group B, and Group C (largest).

RESULTS

Patients in Group C had greater LL preoperatively (51.5° vs. 47.9° vs. 43.2, P=0.005) and postoperatively (52.2° vs. 48.9° vs. 45.7°, P=0.043). There was no significant difference in the ∆LL values between groups (P>0.05). Patients in Group C had larger SS preoperatively (35.2° vs. 32.1° vs. 30.0°, P=0.010) and postoperatively (36.1° vs. 33.0° vs. 31.7°, P=0.030). Regression analysis showed that PVM/BMI was a significant predictor of LL preoperatively (P=0.039) and postoperatively (P=0.031), as well as SS preoperatively (P=0.001) and postoperatively (P<0.001).

CONCLUSION

Muscle mass of the paravertebral muscles significantly impacts lumbar lordosis and sacral slope in patients with lumbar spinal stenosis before and after posterior lumbar decompression. These findings highlight a need to address risk factors for poor muscle quality in patients with sagittal imbalance.

Circulating microRNAs May Be Predictive of Degenerative Cervical Myelopathy

STUDY DESIGN

Basic Science.

OBJECTIVE

The objective of this study was to identify a unique serum profile of circulating miRNAs and inflammatory markers in patients with degenerative cervical myelopathy (DCM) compared to healthy controls (HC).

SUMMARY OF BACKGROUND DATA

Currently, DCM is diagnosed with a combination of history, physical examination, and close correlation to advanced imaging. To date, no serum marker has been identified to be diagnostic of this condition.

METHODS

Whole venous blood was collected from patients with DCM as well as healthy age- and sex-matched controls. miRNA was extracted from venous blood and a screening analysis was initially conducted to identify miRNA dysregulation in DCM patients. RT-qPCR was used to analyze the expression of 2 specific miRNAs based on screening analysis and literature review. Bioinformatics analysis was used to identify gene networks and potential targets of the miRNA. In addition, the serum inflammatory profile of DCM and HC groups was differentiated using a pro-inflammatory panel.

RESULTS

Thirty-six patients were enrolled in the DCM group (36.1% male, 61.5±9.5 y) while 35 patients were enrolled in the HC group (31.4% male, 57.5±8.9 y). Of the 15 total miRNAs differentially expressed between DCM and HC groups, two were selected for further analysis: miR-223-3p (upregulated) and miR-451a (downregulated). Functional gene network analysis revealed the highest-ranking gene network was involved in neurological disease, while the most overexpressed miRNA in this network (miR-233-3p) was noted to have over 100 targets including CDKN1B and the insulin receptor. Serum cytokine analysis showed significant upregulation of several pro-inflammatory cytokines in the DCM cohort compared to the HC group.

CONCLUSION

DCM patients demonstrated a set of unique circulating miRNAs in addition to a different serum inflammatory profile compared to HC. These miRNAs may potentially serve as targets for future therapeutic intervention or diagnostic/prognostic testing.

Development and psychometric properties of appraisals of post traumatic spinal cord injury health scale in Iran

STUDY DESIGN

Development and psychometrics study OBJECTIVE: To evaluate the reliability and validity of a new version of Appraisals of Post-Traumatic Spinal Cord Injury Health Scale (APTSCIHS) in the Persian language for persons with spinal cord injury (SCI).

SETTING

The persons were selected from National Spinal Cord Injury Registry of Iran (NSCIR-IR) and Brain and Spinal Cord Injury Research center (BASIR).

METHOD

This was a mixed sequential exploratory study that performed in two phases. In the qualitative phase, a systematic scoping review and 12 interviews with the participants were done. Finally, items were generated. In the quantitative phase, face, content, construct and convergent validity were assessed to evaluate validity. To evaluate construct validity, a cross-sectional study was conducted on 305 persons with TSCI along with internal consistency and stability assessments. All quantitative data analyses were conducted using SPSS 22 software.

RESULTS

The content validity and reliability were indicated by Scale's Content Validity Ratio (S-CVR) = 0.73 and Scale's Content Validity Index (S-CVI) = 0.86, Cronbach's α = 0.9 and the Test re-test reliability using intra-class correlations were (ICC) = 0.97 to 0.98. Exploratory factor analysis determined eight factors which showed more than 52% of the variance. APTSCIHS had a significant and strong correlation with Appraisals of DisAbility Primary and Secondary Scale (ADAPSS) (r = 0.475, P < 0.001).

CONCLUSION

Results showed the 36 items APTSCIHS tool had an acceptable validity and reliability in Iran, and it can help health care providers or even administrators improve the quality of the rehabilitation services and quality of life.

The Relationship Between Disc Herniation Morphology and Patient-Reported Outcomes after Microdiscectomy

OBJECTIVE

Determine if herniation morphology based on the Michigan State University Classification is associated with differences in (1) patient-reported outcome measures (or (2) surgical outcomes after a microdiscectomy.

METHODS

Adult patients undergoing single-level microdiscectomy between 2014 and 2021 were identified. Demographics and surgical characteristics were collected through a query search and manual chart review. The Michigan State University classification, which assesses disc herniation laterality (zone A was central, zone B/C was lateral) and degree of extrusion into the central canal (grade 1 was up to 50% of the distance to the intra-facet line, grade >1 was beyond this line), was identified on preoperative MRIs. patient-reported outcome measures were collected at preoperative, 3-month, and 1-year postoperative time points.

RESULTS

Of 233 patients, 84 had zone A versus 149 zone B/C herniations while 76 had grade 1 disc extrusion and 157 had >1 grade. There was no difference in surgical outcomes between groups (P > 0.05). Patients with extrusion grade >1 were found to have lower Physical Component Score at baseline. On bivariate and multivariable logistic regression analysis, extrusion grade >1 was a significant independent predictor of greater improvement in Physical Component Score at three months (estimate = 7.957; CI: 4.443-11.471, P < 0.001), but not at 1 year.

CONCLUSIONS

Although all patients were found to improve after microdiscectomy, patients with disc herniations extending further posteriorly reported lower preoperative physical function but experienced significantly greater improvement three months after surgery. However, improvement in Visual Analog Scale Leg and back, ODI, and MCS at three and twelve months was unrelated to laterality or depth of disc herniation.

Postoperative C5 Palsy after Anterior or Posterior Decompression for Degenerative Cervical Myelopathy: A Subgroup Analysis of the Multicenter, Prospective, Randomized, Phase III, CSM-Protect Clinical Trial

STUDY DESIGN

Retrospective cohort study of prospectively accrued data.

OBJECTIVE

To evaluate a large, prospective, multicentre dataset of surgically-treated DCM cases on the contemporary risk of C5 palsy with surgical approach.

SUMMARY OF BACKGROUND DATA

The influence of surgical technique on postoperative C5 palsy after decompression for degenerative cervical myelopathy (DCM) is intensely debated. Comprehensive analyses are needed using contemporary data and accounting for covariates.

METHODS

Patients with moderate to severe DCM were prospectively enrolled in the multicenter, randomized CSM-Protect clinical trial and underwent either anterior or posterior decompression between Jan 31, 2012, to May 16, 2017. The primary outcome was the incidence of postoperative C5 palsy, defined as onset of muscle weakness by at least one grade in manual muscle test at the C5 myotome with slight or absent sensory disruption after cervical surgery. Two comparative cohorts were made based on anterior or posterior surgical approach. Multivariate hierarchical mixed-effects logistic regression was used to estimate odds ratios (OR) with 95% confidence intervals (CI) for C5 palsy.

RESULTS

A total of 283 patients were included, and 53.4% underwent posterior decompression. The total incidence of postoperative C5 palsy was 7.4% and was significantly higher in patients that underwent posterior decompression compared to anterior decompression (11.26% vs. 3.03%, P=0.008). After multivariable regression, posterior approach was independently associated with greater than four times the likelihood of postoperative C5 palsy (P=0.017). Rates of C5 palsy recovery were comparable between the two surgical approaches.

CONCLUSION

The odds of postoperative C5 palsy are significantly higher after posterior decompression compared to anterior decompression for DCM. This may influence surgical decision-making when there is equipoise in deciding between anterior and posterior treatment options for DCM.

LEVEL OF EVIDENCE

Therapeutic Level II.

The Impact of Socioeconomic Status on the Presence of Advance Care Planning Documents in Patients With Acute Cervical Spinal Cord Injury

INTRODUCTION

Patients presenting with spinal cord injury (SCI) often times have notable deficits or polytrauma and may require urgent decision making for early management. However, their presentation may affect decision-making ability. Although advance care planning (ACP) may help guide spine surgeons as to patient preferences, the rate at which they are available and disparities in ACP completion are still not understood. The objective of this study was to evaluate disparities in the completion of ACP among patients with acute SCI.

METHODS

All patients presenting with cervical SCI to the emergency department at an urban, tertiary level I trauma center from 2010 to 2021 were identified from a prospective database of all consults evaluated by the spine service. Each patient's medical record was reviewed to assess for the presence of ACP documents such as living will, power of attorney, or advance directive. Community-level socioeconomic status was assessed using the Distressed Communities Index. Bivariable and multivariable analyses were performed.

RESULTS

We identified 424 patients: 104 (24.5%) of whom had ACP. Patients with ACP were older (64.8 versus 56.5 years, P = 0.001), more likely White (78.8% versus 71.9%, P = 0.057), and present with ASIA Impairment Scale grade A SCI (21.2% versus 12.8%, P = 0.054), although the latter two did not reach statistical significance. On multivariable logistic regression, patients residing in at-risk communities were significantly less likely to have ACP documents compared with those in prosperous communities (odds ratio [OR]: 0.29, P = 0.03). Although patients living in distressed communities were less likely to complete ACP compared with those in prosperous communities (OR 0.50, P = 0.066), this did not meet statistical significance. Female patients were also less likely to have ACP (OR: 0.43, P = 0.005).

CONCLUSION

Female patients and those from at-risk communities are markedly less likely to complete ACP. Attention to possible disparities during admission and ACP discussions may help ensure that patients of all backgrounds have treatment goals documented.

Do Busier Surgeons Have Lower Intraoperative Costs? An Analysis of Anterior Cervical Discectomy and Fusion Using Time-Driven Activity-Based Costing

STUDY DESIGN

The present study is a single-center, retrospective cohort study of patients undergoing neurosurgical anterior cervical discectomy and fusion (ACDF).

OBJECTIVE

Our objective was to use time-driven activity-based costing (TDABC) methodology to determine whether surgeons' case volume influenced the true intraoperative costs of ACDFs performed at our institution.

SUMMARY OF BACKGROUND DATA

Successful participation in emerging reimbursement models, such as bundled payments, requires an understanding of true intraoperative costs, as well as the modifiable drivers of those costs. Certain surgeons may have cost profiles that are favorable for these "at-risk" reimbursement models, while other surgeons may not.

METHODS

Total cost was divided into direct and indirect costs. Individual costs were obtained by direct observation, electronic medical records, and through querying multiple departments (business operations, sterile processing, plant operations, and pharmacy). Timestamps for all involved personnel and material resources were documented. All surgeons performing ACDFs at our primary and affiliated hospital sites from 2017 to 2022 were divided into four volume-based cohorts: 1-9 cases (n=10 surgeons, 38 cases), 10-29 cases (n=7 surgeons, 126 cases), 30-100 cases (n=3 surgeons, 234 cases), and > 100 cases (n=2 surgeons, 561 cases).

RESULTS

The average total intraoperative cost per case was $7,116 +/- $2,945. The major cost contributors were supply cost ($4,444, 62.5%) and personnel cost ($2,417, 34.0%). A generalized linear mixed model utilizing Poisson distribution was performed with the surgeon as a random effect. Surgeons performing 1-9 total cases, 10-29 cases, and 30-100 cases had increased total cost of surgery (P < 0.001; P < 0.001; and P<0.001, respectively) compared to high-volume surgeons (> 100 cases). Among all volume cohorts, high-volume surgeons also had the lowest mean supply cost, personnel cost, and operative times, while the opposite was true for the lowest-volume surgeons (1-9 cases).

CONCLUSION

It is becoming increasingly important for hospitals to identify modifiable sources of variation in cost. We demonstrate a novel use of TDABC for this purpose.

LEVEL OF EVIDENCE

Level-III.

A Longitudinal Evaluation of Coronavirus Disease 2019 and Its Effects on Spinal Decompressions With or Without Fusion

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

The objectives were to (1) compare the safety of spine surgery before and after the emergence of coronavirus disease 2019 (COVID-19) and (2) determine whether patients with a history of COVID-19 were at increased risk of adverse events.

SUMMARY AND BACKGROUND DATA

The COVID-19 pandemic had a tremendous impact on several health care services. In spine surgery, elective cases were canceled and patients received delayed care due to the uncertainty of disease transmission and surgical outcomes. As new coronavirus variants arise, health care systems require guidance on how to provide optimal patient care to all those in need of our services.

PATIENTS AND METHODS

A retrospective review of patients undergoing spine surgery between January 1, 2019 and June 30, 2021 was performed. Patients were split into pre-COVID or post-COVID cohorts based on local government guidelines. Inpatient complications, 90-day readmission, and 90-day mortality were compared between groups. Secondary analysis included multiple logistic regression to determine independent predictors of each outcome.

RESULTS

A total of 2976 patients were included for analysis with 1701 patients designated as pre-COVID and 1275 as post-COVID. The pre-COVID cohort had fewer patients undergoing revision surgery (16.8% vs 21.9%, P < 0.001) and a lower home discharge rate (84.5% vs 88.2%, P = 0.008). Inpatient complication (9.9% vs 9.2%, P = 0.562), inpatient mortality (0.1% vs 0.2%, P = 0.193), 90-day readmission (3.4% vs 3.2%, P = 0.828), and 90-day mortality rates (0.8% vs 0.8%, P = 0.902) were similar between groups. Patients with positive COVID-19 tests before surgery had similar complication rates (7.7% vs 6.1%, P = 1.000) as those without a positive test documented.

CONCLUSIONS

After the emergence of COVID-19, patients undergoing spine surgery had a greater number of medical comorbidities, but similar rates of inpatient complications, readmission, and mortality. Prior COVID-19 infection was not associated with an increased risk of postsurgical complications or mortality.

LEVEL OF EVIDENCE

Level III.

Preoperative Hounsfield Units Predict Pedicle Screw Loosening in Osteoporotic Patients Following Short Segment Lumbar Fusion

STUDY DESIGN

Retrospective Cohort.

OBJECTIVE

(1) To determine if vertebral HU values obtained from preoperative CT predict postoperative outcomes following 1-3 level lumbar fusion and (2) to investigate whether decreased BMD values determined by HU predict cage subsidence and screw loosening.

SUMMARY OF BACKGROUND DATA

In light of suboptimal screening for osteoporosis, vertebral computerized tomography(CT) Hounsfield Units(HU), have been investigated as a surrogate for bone mineral density(BMD).

METHODS

In this retrospective study, adult patients who underwent 1-3 level posterior lumbar decompression and fusion(PLDF) or transforaminal lumbar interbody and fusion(TLIF) for degenerative disease between the years 2017-2022 were eligible for inclusion. Demographics and surgical characteristics were collected. Outcomes assessed included 90-day readmissions, 90-day complications, revisions, patient reported outcomes(PROMs), cage subsidence, and screw loosening. Osteoporosis was defined as HU of ≤110 on preoperative CT at L1.

RESULTS

We assessed 119 patients with a mean age of 59.1, of whom 80.7% were white and 64.7% were nonsmokers. The majority underwent PLDF(63%) compared to TLIF(37%), with an average of 1.63 levels fused. Osteoporosis was diagnosed in 37.8% of the cohort with a mean HU in the osteoporotic group of 88.4 compared to 169 in non-osteoporotic patients. Although older in age, osteoporotic individuals did not exhibit increased 90-day readmissions, complications, or revisions compared to non-osteoporotic patients. A significant increase in the incidence of screw loosening was noted in the osteoporotic group with no differences observed in subsidence rates. On multivariable linear regression osteoporosis was independently associated with less improvement in visual analog scale(VAS) scores for back pain.

CONCLUSIONS

Osteoporosis predicts screw loosening and increased back pain. Clinicians should be advised of the importance of preoperative BMD optimization as part of their surgical planning and the utility of vertebral CT HU as a tool for risk stratification.

LEVEL OF EVIDENCE

3.

Global Validation of the AO Spine Upper Cervical Injury Classification: Geographic Region Affects Reliability and Reproducibility

STUDY DESIGN

Global Survey.

OBJECTIVE

To determine the accuracy, interobserver reliability, and intraobserver reproducibility of the AO Spine Upper Cervical Injury Classification System based on surgeons' AO Spine region of practice (Africa, Asia, Central/South America, Europe, Middle East, and North America).

METHODS

A total of 275 AO Spine members assessed 25 upper cervical spine injuries and classified them according to the AO Spine Upper Cervical Injury Classification System. Reliability, reproducibility, and accuracy scores were obtained over two assessments administered at three-week intervals. Kappa coefficients (ƙ) determined the interobserver reliability and intraobserver reproducibility.

RESULTS

On both assessments, participants from Europe and North America had the highest classification accuracy, while participants from Africa and Central/South America had the lowest accuracy (P < .0001). Participants from Africa (assessment 1 (AS1):ƙ = .487; AS2:0.491), Central/South America (AS1:ƙ = .513; AS2:0.511), and the Middle East (AS1:0.591; AS2: .599) achieved moderate reliability, while participants from North America (AS1:ƙ = .673; AS2:0.648) and Europe (AS1:ƙ = .682; AS2:0.681) achieved substantial reliability. Asian participants obtained substantial reliability on AS1 (ƙ = .632), but moderate reliability on AS2 (ƙ = .566). Although there was a large effect size, the low number of participants in certain regions did not provide adequate certainty that AO regions affected the likelihood of participants having excellent reproducibility (P = .342).

CONCLUSIONS

The AO Spine Upper Cervical Injury Classification System can be applied with high accuracy, interobserver reliability, and intraobserver reproducibility. However, lower classification accuracy and reliability were found in regions of Africa and Central/South America, especially for severe atlas injuries (IIB and IIC) and atypical hangman's type fractures (IIIB injuries).

Validation of the AO Spine CROST (Clinician Reported Outcome Spine Trauma) in the clinical setting

PURPOSE

To evaluate feasibility, internal consistency, inter-rater reliability, and prospective validity of AO Spine CROST (Clinician Reported Outcome Spine Trauma) in the clinical setting.

METHODS

Patients were included from four trauma centers. Two surgeons with substantial amount of experience in spine trauma care were included from each center. Two separate questionnaires were administered at baseline, 6-months and 1-year: one to surgeons (mainly CROST) and another to patients (AO Spine PROST-Patient Reported Outcome Spine Trauma). Descriptive statistics were used to analyze patient characteristics and feasibility, Cronbach's α for internal consistency. Inter-rater reliability through exact agreement, Kappa statistics and Intraclass Correlation Coefficient (ICC). Prospective analysis, and relationships between CROST and PROST were explored through descriptive statistics and Spearman correlations.

RESULTS

In total, 92 patients were included. CROST showed excellent feasibility results. Internal consistency (α = 0.58-0.70) and reliability (ICC = 0.52 and 0.55) were moderate. Mean total scores between surgeons only differed 0.2-0.9 with exact agreement 48.9-57.6%. Exact agreement per CROST item showed good results (73.9-98.9%). Kappa statistics revealed moderate agreement for most CROST items. In the prospective analysis a trend was only seen when no concerns at all were expressed by the surgeon (CROST = 0), and moderate to strong positive Spearman correlations were found between CROST at baseline and the scores at follow-up (rs = 0.41-0.64). Comparing the CROST with PROST showed no specific association, nor any Spearman correlations (rs = -0.33-0.07).

CONCLUSIONS

The AO Spine CROST showed moderate validity in a true clinical setting including patients from the daily clinical practice.

Cellular Bone Matrix in Spine Surgery - Are They Worth the Risk: A Systematic Review

STUDY DESIGN

Systematic Review.

OBJECTIVE

To review the literature for complications and outcomes after the implantation of cellular bone matrix (CBM) during spine fusion.

METHODS

The PubMed database was queried from inception to January 31, 2023 for any articles that discussed the role of and identified a specific CBM in spinal fusion procedures. Adverse events, reoperations, methods, and fusion rates were collected from all studies and reported.

RESULTS

Six hundred articles were identified, of which 19 were included that reported outcomes of 7 different CBM products. Seven studies evaluated lumbar fusion, 11 evaluated cervical fusion, and 1 study reported adverse events of a single CBM product. Only 4 studies were comparative studies while others were limited to case series. Fusion rates ranged from 68% to 98.7% in the lumbar spine and 87% to 100% in the cervical spine, although criteria for radiographic fusion was variable. While 7 studies reported no adverse events, there was no strict consensus on what constituted a complication. One study reported catastrophic disseminated tuberculosis from donor contaminated CBM. The authors of 14 studies had conflicts of interest with either the manufacturer or distributor for their analyzed CBM.

CONCLUSIONS

Current evidence regarding the use of cellular bone matrix as an osteobiologic during spine surgery is weak and limited to low-grade non-comparative studies subject to industry funding. While reported fusion rates are high, the risk of severe complications should not be overlooked. Further large clinical trials are required to elucidate whether the CBMs offer any benefits that outweigh the risks.

Impact of Weekday on Short-term Surgical Outcomes After Lumbar Fusion Surgery

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The purpose of this study is to investigate whether weekday lumbar spine fusion surgery has an impact on surgical and inpatient physical therapy (PT) outcomes.

SUMMARY OF BACKGROUND DATA

Timing of surgery has been implicated as a factor that may impact outcomes after spine surgery. Previous literature suggests that there may be an adverse effect to having surgery on the weekend.

METHODS

All patients ≥18 years who underwent primary lumbar spinal fusion from 2014 to 2020 were retrospectively identified. Patients were subdivided into an early subgroup (surgery between Monday and Wednesday) and a late subgroup (surgery between Thursday and Friday). Surgical outcome variables included inpatient complications, 90-day readmissions, and 1-year revisions. PT data from the first inpatient PT session included hours to PT session, AM-PAC Daily Activity or Basic Mobility scores, and total gait trial distance achieved.

RESULTS

Of the 1239 patients identified, 839 had surgery between Monday and Wednesday and 400 had surgery between Thursday and Friday. Patients in the later surgery subgroup were more likely to experience a nonsurgical neurologic complication (3.08% vs. 0.86%, P=0.008); however, there was no difference in total complications. Patients in the early surgery subgroup had their first inpatient PT session earlier than patients in the late subgroup (15.7 vs. 18.9 h, P<0.001). However, patients in the late subgroup achieved a farther total gait distance (98.2 vs. 75.4, P=0.011). Late surgery was a significant predictor of more hours of PT (est.=0.256, P=0.016) and longer length of stay (est.=2.277, P=0.001). There were no significant differences in readmission and revision rates.

CONCLUSIONS

Patients who undergo surgery later in the week may experience more nonsurgical neurologic complications, longer wait times for inpatient PT appointments, and longer lengths of stay. This analysis showed no adverse effect of later weekday surgery as it relates to total complications, readmissions, and reoperations.

LEVEL OF EVIDENCE

Level III.

Radiology Reports Do Not Accurately Portray the Severity of Cervical Neural Foraminal Stenosis

STUDY DESIGN

Retrospective study.

OBJECTIVE

(1) To compare cervical magnetic resonance imaging (MRI) radiology reports to a validated grading system for cervical foraminal stenosis (FS) and (2) to evaluate whether the severity of cervical neural FS on MRI correlates to motor weakness or patient-reported outcomes.

BACKGROUND

Radiology reports of cervical spine MRI are often reviewed to assess the degree of neural FS. However, research looking at the association between these reports and objective MRI findings, as well as clinical symptoms, is lacking.

PATIENTS AND METHODS

We retrospectively identified all adult patients undergoing primary 1 or 2-level anterior cervical discectomy and fusion at a single academic center for an indication of cervical radiculopathy. Preoperative MRI was assessed for neural FS severity using the grading system described by Kim and colleagues for each level of fusion, as well as adjacent levels. Neural FS severity was recorded from diagnostic radiologist MRI reports. Motor weakness was defined as an examination grade <4/5 on the final preoperative encounter. Regression analysis was conducted to evaluate whether the degree of FS by either classification was related to patient-reported outcome measure severity.

RESULTS

A total of 283 patients were included in the study, and 998 total levels were assessed. There were significant differences between the MRI grading system and the assessment by radio-logists (P< 0.001). In levels with moderate stenosis, 28.9% were classified as having no stenosis by radiology. In levels with severe stenosis, 29.7% were classified as having mild-moderate stenosis or less. Motor weakness was found similarly often in levels of moderate or severe stenosis (6.9% and 9.2%, respectively). On regression analysis, no associations were found between baseline patient-reported outcome measures and stenosis severity assessed by radiologists or MRI grading systems.

CONCLUSION

Radiology reports on the severity of cervical neural FS are not consistent with a validated MRI grading system. These radiology reports underestimated the severity of neural foraminal compression and may be inappropriate when used for clinical decision-making.

LEVEL OF EVIDENCE

Level III.

What is the Marginal Cost of Using Robot Assistance or Navigation for Transforaminal Lumbar Interbody Fusion? A Time-Driven Activity-Based Cost Analysis

BACKGROUND AND OBJECTIVE

Our primary objective was to compare the marginal intraoperative cost of 3 different methods for pedicle screw placement as part of transforaminal lumbar interbody fusions (TLIFs). Specifically, we used time-driven activity-based costing to compare costs between robot-assisted TLIF (RA-TLIF), TLIF with intraoperative navigation (ION-TLIF), and freehand (non-navigated, nonrobotic) TLIF.

METHODS

Total cost was divided into direct and indirect costs. We identified all instances of RA-TLIF (n = 20), ION-TLIF (n = 59), and freehand TLIF (n = 233) from 2020 to 2022 at our institution. Software was developed to automate the extraction of all intraoperatively used personnel and material resources from the electronic medical record. Total costs were determined through a combination of direct observation, electronic medical record extraction, and interdepartmental collaboration (business operations, sterile processing, pharmacy, and plant operation departments). Multivariable linear regression analysis was performed to compare costs between TLIF modalities, accounting for patient-specific factors as well as number of levels fused, surgeon, and hospital site.

RESULTS

The average total intraoperative cost per case for the RA-TLIF, ION-TLIF, and freehand TLIF cohorts was $24 838 ± $10 748, $15 991 ± $6254, and $14 498 ± $6580, respectively. Regression analysis revealed that RA-TLIF had significantly higher intraoperative cost compared with both ION-TLIF (β-coefficient: $7383 ± $1575, P < .001) and freehand TLIF (β-coefficient: $8182 ± $1523, P < .001). These cost differences were primarily driven by supply cost. However, there were no significant differences in intraoperative cost between ION-TLIF and freehand TLIF (P = .32).

CONCLUSION

We demonstrate a novel use of time-driven activity-based costing methodology to compare different modalities for executing the same type of lumbar fusion procedure. RA-TLIF entails significantly higher supply cost when compared with other modalities, which explains its association with higher total intraoperative cost. The use of ION, however, does not add extra expense compared with freehand TLIF when accounting for confounders. This might have implications as surgeons and hospitals move toward bundled payments.

Evaluation of perioperative care and drivers of cost in geriatric thoracolumbar trauma

Introduction

As the population of elderly patients continues to rise, the number of these individuals presenting with thoracolumbar trauma is expected to increase.

Research question

To investigate thoracolumbar fusion outcomes for patients with vertebral fractures as stratified by decade. Secondarily, we examined the variability of cost across age groups by identifying drivers of cost of care.

Materials and methods

We queried the United States Nationwide Inpatient Sample(NIS) for adult patients undergoing spinal fusion for thoracolumbar fractures between 2012 and 2017. Patients were stratified by decade 60-69(sexagenarians), 70-79(septuagenarians) and 80-89(octogenarians). Bivariable analysis followed by multivariable regression was performed to assess independent predictors of length of stay(LOS), hospital cost, and discharge disposition.

Results

A total of 2767 patients were included, of which 46%(N = 1268) were sexagenarians, 36% septuagenarians and 18%(N = 502) octogenarians. Septuagenarians and octogenarians had shorter LOS compared to sexagenarians(ß = -0.88 days; p = 0.012) and(ß = -1.78; p < 0.001), respectively. LOS was reduced with posterior approach(-2.46 days[95% CI: 3.73-1.19]; p < 0.001), while Hispanic patients had longer LOS(+1.97 [95% CI: 0.81-3.13]; p < 0.001). Septuagenarians had lower total charges $12,185.70(p = 0.040), while the decrease in charges in octogenarians was more significant, with a decrease of $26,016.30(p < 0.001) as compared to sexagenarians. Posterior approach was associated with a decrease of $24,337.90 in total charges(p = 0.026). Septuagenarians and octogenarians had 1.72 higher odds(p < 0.001) and 4.16 higher odds(p < 0.001), respectively, of discharge to a skilled nursing facility.

Discussion and conclusions

Healthcare utilization in geriatric thoracolumbar trauma is complex. Cost reductions in the acute hospital setting may be offset by unaccounted costs after discharge. Further research into this phenomenon and observed racial/ethnic disparities must be pursued.

Opioid Use Increases the Rate of Pseudarthrosis and Revision Surgery in Patients Undergoing Anterior Cervical Discectomy and Fusion

STUDY DESIGN

Retrospective Cohort.

OBJECTIVES

To (1) quantify the risk opioids impart on pseudarthrosis development, (2) analyze the effect of pseudarthrosis on clinical outcomes, and (3) identify if the amount of opioids prescribed are predictive of pseudarthrosis revision.

METHODS

Patients who underwent ACDF at a single institution between 2017-2019 were retrospectively identified. Postoperative dynamic cervical spine radiographs were reviewed to assess fusion status. Logistic regression models measured the effect of morphine milligram equivalents (MME) prescribed on the likelihood of pseudarthrosis development. Receiver operating characteristic (ROC) curves were generated to predict the probability of surgical revision based on MME prescribed.

RESULTS

Of 298 included patients, an average of 2.01 ± 0.82 levels were included in the construct and 121 (40.9%) patients were diagnosed with a pseudarthrosis. However, only 14 (4.7%) required a pseudarthrosis revision. Patients requiring pseudarthrosis revision had worse one-year postoperative Δ PCS-12 (-1.70 vs. 7.58, P = 0.004), Δ NDI (3.33 vs. -15.26, P = 0.002), and Δ VAS Arm (2.33 vs. -2.48, P = .047). Multivariate logistic regression analyses found the three-month postoperative (OR=1.00, P = .010), one-year postoperative (OR=1.001, P = 0.025), and combined pre- and postoperative MME (OR=1.000, P = .035) increased the risk of pseudarthrosis. ROC analysis identified cutoff values to predict pseudarthrosis revision at 90.00 (area under the curve (AUC): 0.693, confidence interval (CI): 0.554-0.832), 132.86 (0.710, CI: 0.589-0.840), 224.76 (0.687, CI: 0.558-0.817) and 285.00 (0.711, CI: 0.585-0.837) MME in the preoperative, three-month postoperative, one-year postoperative, and combined pre-and postoperative period.

CONCLUSION

Increased prescription of opioid medications following ACDF procedures may increase the risk of pseudarthrosis development and revision surgery.

LEVEL OF EVIDENCE

Therapeutic Level III.

The Effect of Preoperative Marijuana Use on Surgical Outcomes, Patient-Reported Outcomes, and Opioid Consumption Following Lumbar Fusion

STUDY DESIGN

Retrospective Cohort Study.

OBJECTIVES

To (1) investigate the effect of marijuana use on surgical outcomes following lumbar fusion, (2) determine how marijuana use affects patient-reported outcomes measures (PROMs), and (3) determine if marijuana use impacts the quantity of opioids prescribed.

METHODS

Patients > 18 years of age who underwent primary one- or two-level lumbar fusion with preoperative marijuana use at our institution were identified. A 3:1 propensity match incorporating patient demographics and procedure type was conducted to compare preoperative marijuana users to non-marijuana users. Patient demographics, surgical characteristics, surgical outcomes (90-day all-cause and 90-day surgical readmissions, reoperations, and revision surgeries), pre- and postoperative narcotic usage, and PROMs were compared between groups. Multivariate regression models were created to determine the effect of marijuana on surgical reoperations patient-reported outcomes (PROMs) 1-year postoperatively.

RESULTS

Of the 259 included patients, 65 used marijuana preoperatively. Multivariate logistic regression analysis demonstrated that marijuana use (OR = 2.28, P = .041) significantly increased the likelihood of having a spine reoperation. No other surgical outcome was found to be significantly different between groups. Multivariate linear regression analysis showed that marijuana use was not significantly associated with changes in 1-year postoperative PROMs (all, P > .05). The quantity of pre- and postoperative opioids prescriptions was not significantly different between groups (all, P > .05).

CONCLUSIONS

Preoperative marijuana use increased the likelihood of a spine reoperation for any indication following lumbar fusion, but it was not associated with 90-day all cause readmission, surgical readmission, the magnitude of improvement in PROMs, or differences in opioid consumption.

LEVEL OF EVIDENCE

III.

The Effect of Muscle Quality on Outcomes after Microdiscectomy

OBJECTIVES

To investigate the relationship between muscle quality and 1) patient-reported outcomes and 2) surgical outcomes after lumbar microdiscectomy surgery.

METHODS

Adult patients (≥18 years) who underwent lumbar microdiscectomy from 2014 to 2021 at a single academic institution were identified. Outcomes were collected during the preoperative, 3-month, 6-month, and 1-year postoperative periods. Those included were the Oswestry Disability Index (ODI), Visual Analog Scale Back and Leg (VAS-Back and VAS-Leg, respectively), and the mental and physical component of the short-form 12 survey (MCS and PCS). Muscle quality was determined by 2 systems: the normalized total psoas area (NTPA) and a paralumbar-based grading system. Surgical outcomes including 90-day surgical readmissions and 1-year reoperations were also collected.

RESULTS

Of the 218 patients identified, 150 had good paralumbar muscle quality and 165 had good psoas muscle quality. Bivariant analysis demonstrated no difference between groups regarding surgical outcomes (P > 0.05). Multivariable analysis demonstrated that better paralumbar muscle quality was not associated with any consistent changes in patient reported outcomes. Higher NTPA was associated with improved PCS at 6 months (est. = 6.703, [95% CI: 0.759-12.646], P = 0.030) and 12 months (est. = 6.625, [95% CI: 0.845-12.405], P = 0.027). There was no association between muscle quality and surgical readmissions or reoperations.

CONCLUSIONS

Our analysis demonstrated that higher psoas muscle quality was associated with greater physical improvement postoperatively. Muscle quality did not affect surgical readmissions or reoperations. Additional studies are needed for further assessment of the implications of muscle quality on postoperative outcomes.

Using Oswestry Disability Index as a Preoperative Surgical Eligibility Criterion for Patients Requiring Lumbar Fusion for Degenerative Lumbar Spine Disease

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To evaluate how preoperative Oswestry Disability Index (ODI) thresholds might affect minimal clinically important difference (MCID) achievement following lumbar fusion.

SUMMARY OF BACKGROUND DATA

As payers invest in alternative payment models, some are suggesting threshold cutoffs of patient reported outcomes (PROMs) in reimbursement approvals for orthopedic procedures. The feasibility of this has not been investigated in spine surgery.

MATERIALS/METHODS

We included all adult patients undergoing 1-3 level primary lumbar fusion at a single urban tertiary academic center from 2014-2020. ODI was collected preoperatively and one-year postoperatively. We implemented theoretical threshold cutoffs at increments of 10. MCID was set at 14.3. The percent of patients meeting MCID were determined among patients "approved" or "denied" at each threshold. At each threshold, the positive predictive value (PPV) for MCID attainment was calculated.

RESULTS

A total 1,368 patients were included and 62.4% (N=364) achieved MCID. As the ODI thresholds increased, a greater percent of patients in each group reached the MCID. At the lowest ODI threshold, 6.58% (N=90) of patients would be denied, rising to 20.2%, 39.5%, 58.4%, 79.9%, and 91.4% at ODI thresholds of 30, 40, 50, 60, and 70, respectively. The PPV increased from 0.072 among patients with ODI>20 to 0.919 at ODI>70. The number of patients denied a clinical improvement in the denied category per patient achieving the MCID increased at each threshold (ODI>20: 1.96; ODI>30: 2.40; ODI>40: 2.75; ODI>50: 3.03; ODI>60: 3.54; ODI>70: 3.75).

CONCLUSION

Patients with poorer preoperative ODI are significantly more likely to achieve MCID following lumbar spine fusion at all ODI thresholds. Setting a preoperative ODI threshold for surgical eligibility will restrict access to patients who may benefit from spine fusion, despite ODI>20 demonstrating the lowest predictive value for MCID achievement.

In-hospital mortality trends after surgery for traumatic thoracolumbar injury: A national inpatient sample database study

Introduction

Given the increasing incidence of traumatic thoracolumbar injuries in recent years, studies have sought to investigate potential risk factors for outcomes in these patients.

Research question

The aim of this study was to investigate trends and risk factors for in-hospital mortality after fusion for traumatic thoracolumbar injury.

Materials and methods

Patients undergoing thoracolumbar fusion after traumatic injury were queried from the National Inpatient Sample (NIS) from 2012 to 2017. Analysis was performed to identify risk factors for inpatient mortality after surgery.

Results

Patients in 2017 were on average older (51.0 vs. 48.5, P = 0.004), had more admitting diagnoses (15.5 vs. 10.7, p < 0.001), were less likely to be White (75.8% vs. 81.2%, p = 0.006), were from a ZIP code with a higher median income quartile (Quartile 1: 31.4% vs. 28.6%, p = 0.011), and were more likely to have Medicare as a primary payer (22.9% vs. 30.1%, p < 0.001). Bivariate analysis of demographics and surgical characteristics demonstrated that patients in the in-hospital mortality group (n = 90) were older (70.2 vs. 49.6, p < 0.001), more likely to be male (74.4% vs. 62.8%, p = 0.031), had a great number of admitted diagnoses (21.3 vs. 12.7, p < 0.001), and were more likely to be insured by Medicare (70.0% vs. 27.0%, p < 0.001). Multivariate regression analysis found age (OR 1.06, p < 0.001) and Black race (OR 3.71, p = 0.007) were independently associated with in-hospital mortality.

Conclusion

Our study of nationwide, traumatic thoracolumbar fusion procedures from 2012 to 2017 in the NIS database found older, black patients were at increased risk for in-hospital mortality after surgery.

Does operative level impact dysphagia severity following anterior cervical discectomy and fusion? a multicenter prospective analysis

STUDY DESIGN

Prospective multi-center cohort study.

OBJECTIVE

To explore the association between operative level and postoperative dysphagia after anterior cervical discectomy and fusion (ACDF).

SUMMARY OF BACKGROUND DATA

Dysphagia is common following ACDF and has several risk factors including soft tissue edema. The degree of prevertebral soft tissue edema varies based upon the operative cervical level. However, the operative level has not been evaluated as a source of postoperative dysphagia.

METHODS

Adult patients undergoing elective ACDF were prospectively enrolled at three academic centers. Dysphagia was assessed using the Bazaz questionnaire, Dysphagia Short Questionnaire (DSQ), and Eating Assessment Tool-10 (EAT-10) preoperatively and at 2, 6, 12, and 24-weeks postoperatively. Patients were grouped based on inclusion of specific surgical levels in the fusion construct. Multivariable regression analyses were performed evaluating the independent effects of number of surgical levels and inclusion of each particular level on dysphagia symptoms.

RESULTS

A total of 130 patients were included. Overall, 24 (18.5%) patients had persistent postoperative dysphagia at 24 weeks and were older, female, and less likely to be drink alcohol. There was no difference in operative duration or dexamethasone administration. Patients with persistent dysphagia were significantly more likely to have C4-C5 included in the fusion construct (62.5% vs. 34.9%, P=0.024) but there were no differences based on inclusion of other levels. On multivariable regression, inclusion of C3-C4 or C6-C7 were associated with more severe EAT-10 (β:9.56, P=0.016 and β:8.15, P=0.040) and DSQ (β:4.44, P=0.023 and (β:4.27, P=0.030) at 6 weeks. At 12-weeks, C3-C4 fusion was also independently associated with more severe dysphagia (EAT-10 β:4.74, P=0.024).

CONCLUSION

The location of prevertebral soft tissue swelling may impact the duration and severity of patient-reported dysphagia outcomes at up to 24 weeks postoperatively. In particular, inclusion of C3-C4 and C4-C5 into the fusion may be associated with dysphagia severity.