Faculty Bibliography

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: VBT takes advantage of the Hueter-Volkmann principle, and modulates growth across intervertebral disc spaces with a tensioned tether secured at the lateral aspects of vertebral bodies. Cervical deformity in AIS patients is associated with lower health related quality of life. PSF constructs have been shown to improve cervical deformity, however, to date, these relationships have not been described in patients treated with VBT. PURPOSE: Determine if cervical sagittal alignment parameters following VBT for correction of AIS are similar to what is observed following PSF. STUDY DESIGN/SETTING: Multi-center retrospective cohort study. PATIENT SAMPLE: Patients with AIS that undergo correction surgeries with LIV in the lumbar spine from 2013 to 2021 with pre- and 2-year postop standing full body plain films available. OUTCOME MEASURES: Outcome measures: Age, height, weight, BMI, Risser score, LIV and levels instrumented. Radiographic analysis included pre- and postop C2 to C7 sagittal vertical axis (cSVA), cervical lordosis angle (CL), T1 slope and thoracic kyphosis (TK).
METHOD(S): Measures were compared using independent samples t-tests, significance set at p<0.05.
RESULT(S): A total of 99 patients: 49 VBT and 50 fusions. 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. There were no significant differences with regard to patient age or number of levels instrumented. Patients included in the VBT cohort had a lower level of bone maturity as defined by Risser class (1.6+/-0.9 vs 2.6+/-1.8, p=0.001). The VBT cohort had higher baseline cSVA (3.4mm+/-1.6 vs -1.0mm+/-3.1, 0.001) and less CL (-0.6degree+/-18.2 vs 11.6degree+/-12.8, p=0.001) than the fusion cohort. No differences in baseline T1 slope or Thoracic Kyphosis was observed. VBT patients also had higher 2-year cSVA (3.4mm+/-1.4 vs -3.7mm+/-2.1, p=0.001) and less CL (-4.0+/-18.5 vs 7.0+/-12.2, p=0.001) compared to fusion patients. The PSF group had a significantly greater correction in cSVA than the VBT group (2.8mm+/-4.0 vs 0mm+/-1.6, p=0.001). Both groups displayed improvement in radiographic parameters of cervical and thoracic alignment including CL (VBT 3.3degreevs 4.3degree, p=0.74), T1 slope (VBT -4.3degreevs -4.9degree, p=0.81) and TK (VBT -6.1degreevs -3.9degree, p=0.47). After PSM for Lenke classification, 66 patients remained: 33 VBT, 33 PSF. The PSF group continued to demonstrate greater improvement in cSVA than the VBT group (3.2mm+/-3.0 vs -0.3+/-1.8, p=0.001.
CONCLUSION(S): VBT and PSF both improve radiographic parameters of cervical alignment in AIS patients; however, PSF showed greater correction of cSVA at 2-year followup. 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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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.

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.

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%.

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.

BACKGROUND CONTEXT/BACKGROUND:The COVID-19 pandemic caused nationwide suspensions of elective surgeries due to reallocation of resources to the care of COVID-19 patients. Following resumption of elective cases, a significant proportion of patients continued to delay surgery, with many yet to reschedule, potentially prolonging their pain and impairment of function and causing detrimental long-term effects. PURPOSE/OBJECTIVE:The aim of this study was to examine differences between patients who have and have not rescheduled their spine surgery procedures originally cancelled due to the COVID-19 pandemic, and to evaluate the reasons for continued deferment of spine surgeries even after the lifting of the mandated suspension of elective surgeries. STUDY DESIGN/SETTING/METHODS:Retrospective case series at a single institution PATIENT SAMPLE: Included were 133 patients seen at a single institution where spine surgery was canceled due to a state-mandated suspension of elective surgeries from March to June, 2020. OUTCOME MEASURES/METHODS:The measures assessed included preoperative diagnoses and neurological dysfunction, surgical characteristics, reasons for surgery deferment, and PROMIS scores of pain intensity, pain interference, and physical function. METHODS:Patient electronic medical records were reviewed. Patients who had not rescheduled their canceled surgery as of January 31, 2021, and did not have a reason noted in their charts were called to determine the reason for continued surgery deferment. Patients were divided into three groups: early rescheduled (ER), late rescheduled (LR), and not rescheduled (NR). ER patients had a date of surgery (DOS) prior to the city's Phase 4 reopening on July 20, 2020; LR patients had a DOS on or after that date. Statistical analysis of the group findings included analysis of variance with Tukey's honestly significant difference (HSD) post-hoc test, independent samples T-test, and chi-square analysis with significance set at p≤.05. RESULTS:Out of 133 patients, 47.4% (63) were in the ER, 15.8% (21) in the LR, and 36.8% (49) in the NR groups. Demographics and baseline PROMIS scores were similar between groups. LR had more levels fused (3.6) than ER (1.6), p= .018 on Tukey HSD. NR (2.1) did not have different mean levels fused than LR or ER, both p= >.05 on Tukey HSD. LR had more three column osteotomies (14.3%) than ER and (1.6%) and NR (2.0%) p=.022, and fewer lumbar microdiscectomies (0%) compared to ER (20.6%) and NR (10.2%), p=.039. Other surgical characteristics were similar between groups. LR had a longer length of stay than ER (4.2 vs 2.4, p=.036). No patients in ER or LR had a nosocomial COVID-19 infection. Of NR, 2.0% have a future surgery date scheduled and 8.2% (4) are acquiring updated exams before rescheduling. 40.8% (20; 15.0% total cohort) continue to defer surgery over concern for COVID-19 exposure and 16.3% (8) for medical comorbidities. 6.1% (3) permanently canceled for symptom improvement. 8.2% (4) had follow-up recommendations for non-surgical management. 4.1% (2) are since deceased. CONCLUSION/CONCLUSIONS:Over 1/3 of elective spine surgeries canceled due to COVID-19 have not been performed in the 8 months from when elective surgeries resumed in our institution to the end of the study. ER patients had less complex surgeries planned than LR. NR patients continue to defer surgery primarily over concern for COVID-19 exposure. The toll on the health of these patients as a result of the delay in treatment and on their lives due to their inability to return to normal function remains to be seen.

STUDY DESIGN/METHODS:Retrospective review of a single-center spine database. OBJECTIVE:Investigate the intersections of chronological age and physiological age via frailty to determine the influence of surgical invasiveness on patient outcomes. SUMMARY OF BACKGROUND DATA/BACKGROUND:Frailty is a well-established factor in preoperative risk stratification and prediction of postoperative outcomes. The surgical profile of operative adult spinal deformity (ASD) patients who present as elderly and not frail has yet to be investigated. Our aim was to examine the surgical profile and outcomes of ASD patients who were not frail and elderly. METHODS:Included: ASD patients≥18 years old, ≥4 levels fused, with baseline(BL) and follow up data. Patients were categorized by ASD frailty index: Not Frail[NF], Frail[F], Severely Frail [SF]. An elderly patient was defined as ≥70 years. Patients were grouped into NF/elderly and F/elderly. SRS-Schwab modifiers were assessed at baseline and 1-year(0, +, ++). Logistic regression analysis assessed the relationship between increasing invasiveness, no reoperations, or major complications, and improvement in SRS-Schwab modifiers[Good Outcome]. Decision tree analysis assessed thresholds for an invasiveness risk/benefit cutoff point. RESULTS:598 ASD pts included(55.3yrs, 59.7%F, 28.3 kg/m2). 29.8% of patients were above age 70. At baseline, 51.3% of patients were NF, 37.5% F, and 11.2% SF. 66(11%) of patients were NF and elderly. 24.2% of NF-Elderly patients improved in SRS-Schwab by 1-year and had no reoperation or complication postoperatively. Binary regression analysis found a relationship between worsening SRS-Schwab, postop complication, and reoperation with invasiveness score(OR: 1.056[1.013-1.102], p = 0.011). Risk/benefit cut-off was 10(p = 0.004). Patients below this threshold were 7.9[2.2-28.4] times more likely to have a Good Outcome. 156 patients were elderly and F/SF with 16.7% having Good Outcome, with a risk/benefit cut-off point of <8 (4.4[2.2-9.0], p < 0.001). CONCLUSIONS:Frailty status impacted the balance of surgical invasiveness relative to operative risk in an inverse manner, while the opposite was seen amongst elderly patients with a frailty status less than their chronologic age. Surgeons should perhaps consider incorporation of frailty status over age status when determining realignment plans in patients of advanced age.Level of Evidence: ???