Faculty Bibliography

BACKGROUND CONTEXT: The ACS-NSQIP and SpineSage are both easy to use and readily available online perioperative risk calculators The ACS-NSQIP calculator predicts perioperative complications after surgery, but lacks more spine-specific predictors. The SpineSage platform was developed as a tool built for predicting complications in spine surgery. While a limited number of studies have shown it be predictive of both overall and major medical complications in spine surgery, large external validation studies are limited and none have directly compared NSQIP against SpineSage in the same cohort of spine surgery patients. PURPOSE: Assess the ACS-NSQIP Risk Calculator and SpineSage informatics platform for prediction of perioperative complications in spine surgery STUDY DESIGN/SETTING: Retrospective. PATIENT SAMPLE: A total of 440 patients undergoing thoracolumbar spine with or without fusion. OUTCOME MEASURES: Any complication, serious complication, pneumonia, cardiac, dural tear, SSI, UTI, VTE, reoperation, death and LOS METHODS: Each patient was entered into the ACS-NSQIP and SpineSage calculators and predicted risk for specific complications were directly compared to actual risks. Paired t-tests compared the differences between calculators and their predictability of complications. Patients were ranked based on risk predicted for each complication and the highest tertile for each was isolated. Multivariate regression controlling for age and gender was used to determine if the highest tertile for each risk calculator had predictability in complications following spine surgery.
RESULT(S): Mean LOS 4.2+3 days, EBL 444+300 mL, operative time 256+240 min, and levels instrumented 2.1+2.3. When assessing the four complications predicted by SpineSage there were significant differences in three of the four variables, as SpineSage underpredicted the risk of all and serious-complications (p.5). Both calculator tertiles were trending towards significance for major medical complications (SpineSage: OR: 2.0, [0.94-4.23], p=.073; ACS-NSQIP: OR: 1.8,[0.96-3.48],p=.067). When examining any medical risk, only ACS NSQIP had significant predictability for any medical complication (OR: 2.1, [1.3-3.3]; p=.003).
CONCLUSION(S): Similar to previous studies, the ACS-NSQIP score underpredicted most complications, with the exception of LOS and death. In contrast to previous studies, our data suggest SpineSage was not predictive of actual rates of complications. As both calculators are highly accessible and provide at least some objective perioperative risk data points, we recommend them as a guiding tool but not as an absolute endpoint for clinical decision making as they may be inaccurate and insensitive. Further, higher powered studies elucidating the findings in this study should be conducted. Additionally, the assessment of these calculators for a specific subset of patients, such as deformity, degenerative or pediatrics, can further help guide clinicians regarding the utility of these calculators for their particular patient populations. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Indirect decompression technique may be limited in that it does not include direct removal of the offending intervertebral disc or osteophyte protruding into the canal. PURPOSE: This study evaluates resolution of radiculopathy and perioperative complications in lumbar fusion with indirect or direct decompression techniques. STUDY DESIGN/SETTING: Retrospective analysis of large single center academic institution. PATIENT SAMPLE: This study included 116 single-level lumbar fusion patients with preoperative radiculopathy from 2012 to 2021. OUTCOME MEASURES: Resolution of radiculopathy, visual analog scores (VAS), perioperative complications, motor scores.
METHOD(S): Patients 18 years of age diagnosed with preoperative radiculopathy undergoing single-level lumbar fusion with up to two-year follow-up were grouped by indirect and direct decompression. Direct decompression group included TLIF with or without direct decompression procedure as well as ALIF and LLIF with direct decompression procedure. Indirect decompression group included ALIF and LLIF without direct decompression procedure. Propensity score matching (PSM) was used to control for differences in age between groups. Outcome measures were compared between groups using means comparison tests. Logistic regression analysis was used to correlate decompression type with symptom resolution over time.
RESULT(S): A total of 116 patients were included in this analysis: 58 direct decompression (mean 53.9y, 67.2% female) and 58 indirect decompression (mean 54.6y, 61.4% female). Direct decompression patients experienced greater blood loss relative to indirect decompression patients (242.4 +/- 128.5 vs 171.79 +/- 143.9 mL, p=0.007). Additionally, direct decompressionpatients experienced full resolution of radiculopathy at 3 months postop at a greater rate than those in the indirect decompression group (OR: 4.742, [1.97-11.41]; 53.1% vs 13.73%, p=0.002). At 6 months, direct decompression patients demonstrated a significantly larger reduction in VAS score 6 months postop (-2.889 +/- 2.3 vs -0.897 +/- 4.3, p=0.044). With regard to motor function, direct decompression patients had improved motor score with respect to the L5 dermatome at 6 months compared to indirect decompression patients (DELTAmotor score from baseline: 0.1714 +/- 0.453 vs -0.024 +/- 0.154, p=0.019).
CONCLUSION(S): Patients who underwent direct decompression experienced significantly greater resolution of preoperative lower extremity radiculopathy at 3 months compared with those who underwent ID alone. At 6 and 12 months, no differences were noted between the two groups. There were no differences in complication rates. At 6 months postop, direct decompression patients had greater improvement in preoperative motor deficit than ID patients. In particularly debilitated patients, these findings may influence surgeons to perform a direct decompression to achieve more rapid resolution of radiculopathy symptoms. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Reducing fluoroscopy time and radiation exposure in the operating room is beneficial for the patient and surgical team. Placement of an interbody device during lateral transpsoas approach is traditionally carried out using anterior-posterior and lateral fluoroscopy. In this setting, 3-dimensional computed tomography (CT)-based spinal navigation of cage and pedicle screw/rod placement for LLIF procedure may result in decreased radiation exposure compared with fluoroscopically-guided LLIF. We sought to present our experience with the use of CT-based spinal navigation for the LLIF procedure and evaluate rates of intraoperative complications and radiation exposure. PURPOSE: To determine if computer-navigation guided LLIF will have equivalent outcomes with decreased radiation dose compared to fluoroscopy-guided LLIF. STUDY DESIGN/SETTING: Single-center retrospective review. PATIENT SAMPLE: This study included 250 patients over 18 years of age who underwent LLIF with <4 levels fused (age: 61.4 +/- 10.8 yrs, BMI: 29.7 +/- 6.1 7 kg/m2). OUTCOME MEASURES: Intraoperative and 90-day complications, radiation exposure and cage placement.
METHOD(S): Patients were separated into two groups: fluoroscopy-guided LLIF (n=224), and navigated LLIF (n=26). Cage placement was assessed on postoperative radiographs by dividing the disc space into quarters, anterior to posterior.
RESULT(S): In terms of operative characteristics, fluoroscopy dosage was significantly greater in the fluoroscopically-guided LLIF cohort (55.1 +/- 57.4 mGy vs 34.0 +/- 24.9 mGy, p=0.002). There were no significant differences between fluoroscopically-guided LLIFs and navigated LLIFs in overall intraoperative complication rate (4% Fluoro vs 0% Nav, p=0.3), rate of durotomy (2.2 % Fluoro vs 0% Nav, p=0.44), or estimated blood loss (322 +/- 330.3 cc Flouro vs 299.5 +/- 198.6 cc Nav, p=0.6). The rate of postoperative complications (26.8% Fluoro vs 26.9% Nav), neurologic complications (5.4% Fluoro vs 3.8% Nav), surgical site infections (1.3% Fluoro vs 3.8% Nav), mechanical complications (1.8% Fluoro vs 0% Nav) was not significantly different. There was no significant difference in the rate of unplanned return to the operating room within 90 days (1.8% Fluoro vs 0% Nav). Cage placement was similar between the two groups (p=0.29).
CONCLUSION(S): We report an average radiation exposure with navigated LLIFs of 34.0 mGy, significantly lower than the 55.1 mGy in the fluoroscopically-guided LLIF group. The length of stay and perioperative complication rate was equivalent between the groups. These data support the use of CT-based navigation for placement of the cage and pedicle screws/rod construct for LLIF procedure. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: In recent years spine surgeons have utilized different techniques and approaches to perform lumbar interbody fusion surgery. We sought to analyze the difference in outcomes between traditional open transforaminal lumbar interbody fusion (O-TLIF), minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF), dual position anterior/lateral lumbar interbody fusion with posterior instrumentation (Dual ALIF/LLIF), and single position anterior/lateral lumbar interbody fusion with posterior instrumentation (Single ALIF/LLIF). PURPOSE: To analyze the perioperative and postoperative outcomes of patient undergoing TLIF, MIS TLIF, Dual ALIF/LLIF, and Single ALIF/LLIF. STUDY DESIGN/SETTING: Retrospective cohort study at a single institution. PATIENT SAMPLE: Patients undergoing O-TLIF, MIS TLIF, Dual ALIF/LLIF, or Single ALIF/LLIF from 2014 to 2020. OUTCOME MEASURES: Operative time, estimated blood loss (EBL), length of stay (LOS), radiation dose, intraoperative and postoperative complications, and return to OR within 90 days.
METHOD(S): Patients who underwent single level lumbar interbody fusion surgery were analyzed. Patient charts were reviewed for operative time, EBL, LOS, radiation dose, intraoperative and postoperative complications, and return to OR within 90 days. Differences were assessed by ANOVA.
RESULT(S): A total of 1,226 patients underwent a single level lumbar interbody fusion (440 O-TLIF, 423 MIS TLIF, 316 Dual ALIF/LLIF, 47 Single ALIF/LLIF). There were no significant differences in BMI or gender between the groups, but in the O-TLIF cohort average age (60) was higher than MIS-TLIF (54), Dual ALIF/LLIF(52), and Single ALIF/LLIF (50) p < 0.001. There were also significant differences in average operative time (221 mins O-TLIF, 212 mins MIS TLIF, 277 mins dual ALIF/LLIF, 277 mins single ALIF/LLIF, p < 0.001), EBL (360 ml O-TLIF, 167ml MIS TLIF, 235 ml Dual ALIF/LLIF, 253 ml Single ALIF/LLIF, p<0.001), radiation dose (20 mGy O-TLIF, 51 mGy MIS TLIF, 43 mGy Dual ALIF/LLIF, 62 mGy Single ALIF/LLIF, p < 0.001). There was no difference in LOS, intraoperative complications, or 90-day complications between the groups, except a higher rate of neurological deficit in dual ALIF/LLIF (1.6%, p < 0.03). Post hoc analysis demonstrated statistical significance in operative time in the Dual ALIF/LLIF as compared to all the other groups. O-TLIF demonstrated a larger EBL and less radiation as compared to all the other groups as well as a longer operative time than Single ALIF/LLIF. Dual ALIF/LLIF demonstrated a longer operative time and increased rate of neurological deficit as compared to MIS TLIF.
CONCLUSION(S): In comparing different techniques for single level lumbar interbody fusion there were similar outcomes in LOS, perioperative complications and 90-day complications between all the groups. Open TLIF was associated with increased estimate blood loss and less radiation than all the other groups Dual position ALIF/LLIF surgery was associated with a longer operative time than all the other groups. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Sagittal alignment is integral to a patient's quality of life. Posterior spinal fusion (PSF) is currently the standard for correcting adolescent idiopathic scoliosis (AIS). Vertebral body tethering (VBT) is a fusionless growth modulating surgical technique used to treat AIS. It relies on the Hueter-Volkmann Law. Indications for this procedure include patients who have coronal curves up to 50degree, growth remaining, and no excessive thoracic kyphosis. VBT has been shown to have good coronal plane deformity correction. There have been fewer examinations of the sagittal effects of VBT. PURPOSE: To determine if VBT is a non-inferior treatment for correction of AIS with regard to sagittal alignment compared to PSF. STUDY DESIGN/SETTING: Multicenter retrospective cohort study. PATIENT SAMPLE: Patients with AIS who underwent correction surgeries with LIV in the lumbar spine from 2013 to 2021 with pre- and minimum two-year postoperative standing full spine plain films. OUTCOME MEASURES: Sagittal vertical axis (SVA), cervical SVA (cSVA), pelvic tilt (PT), thoracic kyphosis (TK), cervical lordosis (CL), L4-S1 lordosis (L4L), T1 pelvic angle (TPA) and pelvic incidence lumbar lordosis mismatch (PI-LL).
METHOD(S): Radiographic analyses was completed with independent samples t-test with significance set to p <0.05.
RESULT(S): A total of 99 patients were included, 49 VBT and 50 PSF. There were no differences in age or levels instrumented between groups. The VBT cohort Lenke class breakdown is 23% 1A, 13% 1C, 31% 3C. 18% 5C, and 15% 6C, while the PSF cohort consisted of 42% 1A, 6% 1B, 2% 2C, 2% 3B, 12% 3C, 2% 5B, 24% 5C, and 10% 6C. At Baseline, the VBT cohort had lower SVA (-0.7mm+/-3.7 vs 2.2mm+/-5.0, p=0.001), CL (-0.9degree+/-18.2 vs 11.6degree+/-12.8, p=0.001), L4-S1 Lordosis (20.7degree+/-16.0 vs 41.6degree+/-10.2, p=0.001), and higher cSVA (3.3mm+/-1.6 vs -0.95mm+/-3.1, p=0.001) than those who were fused. Postoperatively, VBT patients have an overall higher L4-S1 Lordosis (36.0degree+/-10.1vs 18.3degree+/-12.5, p=0.001), cSVA (3.4mm+/-1.4 vs -3.7mm+/-2.1, p=0.001), and lower CL (-4.3degree+/-18.4 vs 7.0degree+/-12.2, p=0.001). The PSF cohort had a larger change in cSVA (2.8mm+/-4.0 vs 0mm+/-1.6, p=0.001) from baseline to 2-year follow-up compared to VBT. No differences in the change of L4-S1 Lordosis (VBT 1.5degree+/-12.3 vs 4.1degree+/-10.9, p=0.3), TPA (VBT -1.6degree+/-6.8 vs -1.4degree+/-8.5, p=0.89), PT (VBT -0.5degree+/-7.8 vs -1.9degree+/-8.5, p=0.42), or PI-LL (0.2degree+/-12.0 vs -0.5degree+/-14.0, p=0.81) were observed.
CONCLUSION(S): VBT and PSF for AIS result in statistically similar changes in sagittal alignment parameters. The fact that we showed similar results comparing sagittal alignment in fusion and VBT groups indicates that VBT is non-inferior from a sagittal perspective. It is important to maintain sagittal alignment when correcting AIS. Future work can examine the long-term effect of VBT on sagittal alignment. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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STUDY DESIGN/METHODS:Single-center retrospective cohort study. OBJECTIVES/OBJECTIVE:To evaluate inpatient MME administration associated with different lumbar spinal fusion surgeries. METHODS:< .05. RESULTS:= .009). There were no significant differences in MME/hour and incidence of ileus between all groups. CONCLUSION/CONCLUSIONS:Patients undergoing MIS TLIF had lower inpatient opioid intake compared to TP and SP ALIF/LLIF, as well as shorter LOS compared to all groups except SP ALIF/LLIF. Thus, it appears that the advantages of minimally invasive surgery are seen in minimally invasive TLIFs.

PURPOSE/OBJECTIVE:Single position surgery has demonstrated to reduce hospital length of stay, operative times, blood loss, postoperative pain, ileus, and complications. ALIF and LLIF surgeries offer advantages of placing large interbody devices under direct compression and can be performed by a minimally invasive approach in the lateral position. Furthermore, simultaneous access to the anterior and posterior column is possible in the lateral position without the need for patient repositioning. The purpose of this study is to outline the anatomical and technical considerations for performing anterior lumbar interbody fusion (ALIF) in the lateral decubitus position. METHODS:Surgical technique and technical considerations for reconstruction of the anterior column in the lateral position by ALIF at the L4-5 and L5-S1 levels. RESULTS:Topics outlined in this review include: Operating room layout and patient positioning; surgical anatomy and approach; vessel mobilization and retractor placement for L4-5 and L5-S1 lateral ALIF exposure, in addition to comparative technique of disc space preparation, trialing and implant placement compared to the supine ALIF procedure. CONCLUSIONS:Anterior exposure performed in the lateral decubitus position allows safe-, minimally invasive access and implant placement in ALIF. The approach requires less peritoneal and vessel retraction than in a supine position, in addition to allowing simultaneous access to the anterior and posterior columns when performing 360° Anterior-Posterior fusion.

Abundant literature exists describing the incidence of dysphagia following anterior cervical surgery; however, there is a paucity of literature detailing the incidence of dysphagia following posterior cervical procedures. Further characterization of this complication is important for guiding clinical prevention and management. Patients ≥ 18 years of age underwent posterior cervical fusion with laminectomy or laminoplasty between C1-T1. Pre- and post-operative dysphagia was assessed by a speech language pathologist. The patient cohort was categorized by approach: Laminectomy + Fusion (LF) and Laminoplasty (LP). Patients were excluded from radiographic analyses if they did not have both baseline and follow-up imaging. The study included 147 LF and 47 LP cases. There were no differences in baseline demographics. There were three patients with new-onset dysphagia in the LF group (1.5% incidence) and no new cases in the LP group (p = 1.000). LF patients had significantly higher rates of post-op complications (27.9% LF vs. 8.5% LP, p = 0.005) but not intra-op complications (6.1% LF vs. 2.1% LP, p = 0.456). Radiographic analysis of the entire cohort showed no significant changes in cervical lordosis, cSVA, or T1 slope. Both group comparisons showed no differences in incidence of dysphagia pre and post operatively. Based on this study, the likelihood of developing dysphagia after LF or LP are similarly low with a new onset dysphagia rate of 1.5%.

PURPOSE/OBJECTIVE:To determine the validity and responsiveness of PROMIS metrics versus the SRS-22r questionnaire in adult spinal deformity (ASD). METHODS:Surgical ASD patients undergoing ≥ 4 levels fused with complete baseline PROMIS and SRS-22r data were included. Internal consistency (Cronbach's alpha) and test-retest reliability [intraclass correlation coefficient (ICC)] were compared. Cronbach's alpha and ICC values ≥ 0.70 were predefined as satisfactory. Convergent validity was evaluated via Spearman's correlations. Responsiveness was assessed via paired samples t tests with Cohen's d to assess measure of effect (baseline to 3 months). RESULTS:One hundred and ten pts are included. Mean baseline SRS-22r score was 2.62 ± 0.67 (domains = Function: 2.6, Pain: 2.5, Self-image: 2.2, Mental Health: 3.0). Mean PROMIS domains = Physical Function (PF): 12.4, Pain Intensity (PI): 91.7, Pain Interference (Int): 55.9. Cronbach's alpha, and ICC were not satisfactory for any SRS-22 and PROMIS domains. PROMIS-Int reliability was low for all SRS-22 domains (0.037-0.225). Convergent validity demonstrated strong correlation via Spearman's rho between PROMIS-PI and overall SRS-22r (- 0.61), SRS-22 Function (- 0.781), and SRS-22 Pain (- 0.735). PROMIS-PF had strong correlation with SRS-22 Function (0.643), while PROMIS-Int had moderate correlation with SRS-22 Pain (- 0.507). Effect size via Cohen's d showed that PROMIS had superior responsiveness across all domains except for self-image. CONCLUSIONS:PROMIS is a valid measure compared to SRS-22r in terms of convergent validity, and has greater measure of effect in terms of responsiveness, but failed in reliability and internal consistency. Surgeons should consider the lack of reliability and internal consistency (despite validity and responsiveness) of the PROMIS to SRS-22r before replacing the traditional questionnaire with the computer-adaptive testing.

INTRODUCTION/BACKGROUND:Patient Reported Outcome Measurement Information System (PROMIS) instruments have been shown to correlate with established patient outcome metrics. The aim of this retrospective study was to determine the MCID for the PROMIS physical domains of Physical Function (PF), Pain Intensity (PI), and Pain Interference (Int) in a population of surgical cervical deformity (CD) patients. METHODS:Surgical CD patients ≥ 18 years old with baseline (BL) and 3-month (3 M) HRQL data were isolated. Changes in HRQLs: ΔBL-3M. An anchor-based methodology was used. The cohort was divided into four groups: 'worse' (ΔEQ5D ≤ -0.12), 'unchanged' (≥0.12, but < -0.12), 'slightly improve' (>0.12, but ≤ 0.24), and 'markedly improved' (>0.24) [0.24 is the MCID for EQ5D]. PROMIS-PF, PI and Int at 3M was compared between 'slightly improved' and 'unchanged'. ROC computed discrete MCID values using the change in PROMIS that yielded the smallest difference between sensitivity ('slightly improved') and specificity ('unchanged'). We repeated anchor-based methods for the Ames-ISSG classification of severe deformity. RESULTS:140 patients were included. EQ5D groups: 9 patients 'worse', 53 'unchanged', 20 'slightly improved', and 57 'markedly improved'. Patients classified as 'unchanged' exhibited a PROMIS-PF improvement of 2.9 ± 17.0 and those 'slightly improved' had an average gain of 13.3 ± 17.8. ROC analysis for the PROMIS-PF demonstrated an MCID of +2.26, for PROMIS-PI of -5.5, and PROMIS-Int of -5.4. In the Ames-ISSG TS-CL severe CD modifier, ROC analysis found MCIDs of PROMIS physical domains: PF of +0.5, PI of -5.2, and Int of -5.4. CONCLUSIONS:MCID for PROMIS physical domains were established for a cervical deformity population. MCID in PROMIS Physical Function was significantly lower for patients with severe cervical deformity.