Faculty Bibliography

OBJECTIVE:The shared decision-making (SDM) process provides an opportunity to answer frequently asked questions (FAQs). The authors aimed to present a concise list of answers to FAQs to aid in SDM for adult spinal deformity (ASD) surgery. METHODS:From a prospective, multicenter ASD database, patients enrolled between 2008 and 2016 who underwent fusions of 5 or more levels with a minimum 2-year follow-up were included. All deformity types were included to provide general applicability. The authors compiled a list of FAQs from patients undergoing ASD surgery and used a retrospective analysis to provide answers. All responses are reported as either the means or the proportions reaching the minimal clinically important difference at the 2-year follow-up interval. RESULTS:Of 689 patients with ASD who were eligible for 2-year follow-up, 521 (76%) had health-related quality-of-life scores available at the time of that follow-up. The mean age at the initial surgery was 58.2 years, and 78% of patients were female. The majority (73%) underwent surgery with a posterior-only approach. The mean number of fused levels was 12.2. Revision surgery accounted for 48% of patients. The authors answered 12 FAQs as follows:1. Will my pain improve? Back and leg pain will both be reduced by approximately 50%.2. Will my activity level improve? Approximately 65% of patients feel improvement in their activity level.3. Will I feel better about myself? More than 70% of patients feel improvement in their appearance.4. Is there a chance I will get worse? 4.1% feel worse at 2 years postoperatively.5. What is the likelihood I will have a complication? 67.8% will have a major or minor complication, with 47.8% having a major complication.6. Will I need another surgery? 25.0% will have a reoperation within 2 years.7. Will I regret having surgery? 6.5% would not choose the same treatment.8. Will I get a blood transfusion? 73.7% require a blood transfusion.9. How long will I stay in the hospital? You need to stay 8.1 days on average.10. Will I have to go to the ICU? 76.0% will have to go to the ICU.11. Will I be able to return to work? More than 70% will be working at 1 year postoperatively.12. Will I be taller after surgery? You will be 1.1 cm taller on average. CONCLUSIONS:The above list provides concise, practical answers to FAQs encountered in the SDM process while counseling patients for ASD surgery.

BACKGROUND: Bone morphogenetic protein (BMP) and allograft containing mesenchymal stem cells (live cell) are popular biologic substitutes for iliac crest autograft used in transforaminal lumbar interbody fusion (TLIF). Use of these agents in the pathogenesis of postoperative radiculitis remains controversial. Recent studies have independently linked minimally invasive (MIS) TLIF with increased radiculitis risk compared to open TLIF. The purpose of this study was to assess the rate of postoperative radiculitis in open and MIS TLIF patients along with its relationship to concurrent biologic adjuvant use. METHODS: Patients ≥18 years undergoing single-level TLIF from June 2012 to December 2018 with minimum 1-year follow-up were included. Outcome measures were rate of radiculitis, intra- and postoperative complications, revision surgery; length of stay (LOS), and estimated blood loss (EBL). RESULTS:= .038, N = 336) compared to other combinations of surgical approach and biologic use. CONCLUSIONS: Neither the MIS approach nor BMP use is an independent risk factor for post-TLIF radiculitis. However, risk of radiculitis significantly increases when they are used in tandem. This should be considered when selecting biological adjuvants for MIS TLIF. LEVEL OF EVIDENCE/METHODS: 3.

STUDY DESIGN/METHODS:This study is a single-center retrospective radiographic review. OBJECTIVES/OBJECTIVE:The objective of this study is to evaluate a novel measurement parameter, mandibular slope (MS), as a measure of horizontal gaze. INTRODUCTION/BACKGROUND:Assessment of sagittal spinal alignment is essential in the evaluation of spinal deformity patients. Ability to achieve a horizontal gaze, a parameter of sagittal alignment, is needed for the performance of daily activities. Standard measures of horizontal gaze, including the gold-standard chin-brow to vertical angle (CBVA) and the surrogate measures McGregor's line (McGS) and Chamberlain's line (CS), require high-quality imaging, precise head positioning, and reliance on difficult to view visual landmarks. A novel measurement parameter, MS, utilizing the caudal margin of the mandible on standard lateral spine radiographs is proposed. METHODS:90 radiographs from spine deformity patients with or without spinal implants from a single center were evaluated. Three spine surgery fellows independently measured CBVA, McGS, CS, and MS at two timepoints at least one week apart to assess accuracy and reliability. MS was measured as the angle created by the inferior edge of the mandibular body and the horizontal. Formulas for calculating CBVA based on the above parameters were derived and compared to the actual CBVA. RESULTS:Mean age was 49.7 years, 76 females and 14 males. CBVA correlated with CS, McGS, and MS, r = 0.85, 0.81, and 0.80, respectively (p < 0.001). Standard error between real CBVA and calculated CBVA using CS (0.4 ± 4.79) and McGS (0.4 ± 3.9) was higher than that calculated using MS (- 0.2 ± 4.3). ICC demonstrated the highest inter-observer reliability with MS (0.999). MS had the highest intra-observer reliabilities 0.975, 0.981, and 0.988 (p < 0.001); CS and McGS also demonstrated high intra-observer reliability. CONCLUSIONS:MS is a promising measure of horizontal gaze that correlates highly with CBVA, has excellent intra- and inter-observer reliability with CBVA, and is easily measured using standard lateral spine radiographs.

The aim of this study was to investigate the cost utility of treating non-frail versus frail or severely frail adult spinal deformity (ASD) patients. 79 surgical ASD patients >18 years with available frailty and ODI data at baseline and 2-years post-surgery (2Y) were included. Utility data was calculated using the ODI converted to the SF-6D. QALYs utilized a 3% discount rate to account for decline to life expectancy (LE). Costs were calculated using the PearlDiver database. ICER was compared between non-operative (non-op.) and operative (op.) NF and F/SF patients at 2Y and LE. When compared to non-operative ASD, the ICER was $447,943.96 vs. $313,211.01 for NF and F/SF at 2Y, and $68,311.35 vs. $47,764.61 for NF and F/SF at LE. Frail and severely frail patients had lower cost per QALY compared to not frail patients at 2Y and life expectancy, and had lower ICER values when compared to a non-operative cohort of ASD patients. While these results support operative correction of frail and severely frail patients, it is important to note that these patients are often at worse baseline disability, which is closely related to frailty scores, and have more opportunity to improve postoperatively. Furthermore, there may be a threshold of frailty that is not operable due to the risk of severe complications that is not captured by this analysis. While future research should investigate economic outcomes at extended follow up times, these findings support the cost effectiveness of ASD surgery at all frailty states.

STUDY DESIGN/METHODS:Retrospective analysis of outcomes in single-level spine and primary hip and knee arthroplasty patients. OBJECTIVE:Compare baseline and post-operative outcomes in patients undergoing spine surgery procedures with total hip arthroplasty (THA) and total knee arthroplasty (TKA) to further define outcomes in orthopedic surgery. SUMMARY OF BACKGROUND DATA/BACKGROUND:Computer-adaptive Patient Reported Outcome Information System (PROMIS) allows for standardized assessment of the Health Related Quality of Life across different disease states. METHODS:Patients who underwent spine surgery (anterior cervical discectomy and fusion, cervical disc replacement, lumbar laminectomy, microscopic lumbar discectomy, transforaminal lumbar interbody fusion or adult reconstruction surgery (THA, TKA) were grouped. Mean Charlson Comorbidity Index (CCI), Baseline (BL) and 6-month (6 M) PROMIS scores of Physical Function, Pain Interference, and Pain Intensity were determined. Paired t-tests compared differences in CCI, BL, 6 M, and change in PROMIS scores for spine and adult reconstruction procedures. RESULTS:304 spine surgery patients (Age=58.1 ± 15.6; 42.9% Female) and 347 adult reconstruction patients (Age=62.9 ± 11.8; 54.1% Female) were compared. Spine surgery groups had more disability and pain at baseline than adult reconstruction patients according to Physical Function [(21.0, 22.2, 9.07, 12.6, 10.4) vs (35.8, 35.0), respectively, p < .01], Pain Interference [(80.1, 74.1, 89.6, 92.5, 90.6) vs (64.0, 63.9), respectively, p < .01] and Pain Intensity [(53.0, 53.1, 58.3, 58.5, 56.1) vs (53.4, 53.8), respectively, p < .01]. At 6 M, spine surgery patients remained more disabled and had more pain compared to adult reconstruction patients. Over the 6-month timespan, spine patients experienced greater improvements than adult reconstruction patients in terms of Physical Function [(+8.7, +22.2, +9.7, +12.9, +12.1) vs (+5.3, +3.9), respectively, p < .01] and Pain Interference scores [(-15.4, -28.1, -14.7, -13.1, -12.3) vs (-8.3, -6.0), respectively, p < .01]. CONCLUSIONS:Spinal surgery patients had lower BL and 6 M PROMIS scores, but greater relative improvement in PROMIS scores compared to adult reconstruction patients. LEVEL OF EVIDENCE/METHODS:3.

BACKGROUND CONTEXT: Numerous strategies are used to minimize PJK in (ASD). The use of PPS is one such strategy. Studying this topic is difficult as there is a lack of homogeneity in the patient population being studied. PURPOSE: Investigate if PPS minimizes the risk of perioperative PJK compared to traditional open techniques. STUDY DESIGN/SETTING: Retrospective review of prospective multicenter adult spinal deformity database PATIENT SAMPLE: Inclusion criteria are age >18, and one of the following: PT>25, PI-LL>10, or SVA>5 cm. OUTCOME MEASURES: NRS leg, ODI, SF-12, EQ5D, SRS-22.
METHOD(S): A prospective database was retrospectively reviewed. Inclusion criteria are age >18, and one of the following: PT>25, PI-LL>10, or SVA>5 cm. Patients were grouped as MIS (all PPS no open component) or OPEN. Propensity matching was used to create 2 equal groups controlling for: age, BMI, Preop (PI-LL, PI, TPA), and post op (PI-LL correction and posterior levels fused). PJK was evaluated in 2 groups: Mild (PJK10) 10degree change from preop and severe (PJK20) a 20degree change, as previously reported.
RESULT(S): A total of 1,023 patients met criteria: 114 MIS and 909 OPEN. MIS were older with higher BMI. No significant difference was found between groups in preop alignment or SRS Schwab classification. OPEN had more levels fused (11.3 vs 5.5), change in PI-LL (14.9 vs 9.3) and LL (16.2 vs 9.7; all p<0.01). After matching: 77 patients in each group with no difference in demographics or levels fused (6.26 +/- 3.7 OPEN; 6.23 +/- 3.4 MIS). At 1YR NRS leg, ODI, SF-12, EQ5D, SRS-22 were equal. MIS had improved NSR Back compared to OPEN (2.6 vs 3.4; p=0.047). Alignment (PI-LL, TPA, SVA, LL, PT, PI) showed no difference preop, 6 weeks or at 1YR. PJK10 was 23.9% OPEN v 20.3% in MIS at 6 weeks and 28.6% and 19.5% at 1 YR (p>0.59). PJK20 was 2.6% in OPEN vs 3.9% in MIS at 1YR (p=1). The PJK angle was not different (4.3 v 4.2). MIS had less EBL (510 v 1574 cc; p=0.000) longer OR time (448 v 373 min; p=0.022) and more interbodies (3.4 vs 2.1; p=0.000). There was no difference in rate of revision surgery (14.3% OPEN vs 10.4%). Major complications occurred more frequently in OPEN (23.4% vs 9.1%).
CONCLUSION(S): While the use of percutaneous fixation intuitively seems protective for PJK, our study found that when controlling for radiographic deformity, deformity correction, demographics and the magnitude of surgical intervention that percutaneous fixation is equivalent to open techniques in rate of perioperative PJK. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Neurologic complications following adult spinal deformity (ASD) are common and may play a role in the outcomes for our patients. Neurologic complications may include radiculopathy, sensory deficit or motor weakness. The impact that these specific complications have on HRQL is unknown. PURPOSE: Neurologic complications are common following ASD. Understanding their impact on Health-related quality of life (HRQL) measures is critical. STUDY DESIGN/SETTING: Retrospective cohort study of prospective ASD database. PATIENT SAMPLE: Retrospective cohort study, 733 patients. OUTCOME MEASURES: Neurologic complications, HRQL scores.
METHOD(S): ASD patients (>18yrs, scoliosis >=20degree, SVA >=5cm, PT >=25degree and/or TK >60degree). Inclusion criteria was HRQL at baseline (BL) and 1 year, and lower extremity motor score (LEMS) at BL, 6-week and 1-year ODI, SRS22r and SF36 were determined at BL and 1yr LEMS was calculated from 0-50, with 50 designated as normal motor function. Patients were divided into 4 groups: pLEMS (perfect, no deficit), dLEMS (new postop deficit that returned to normal at 1 year), iLEMS (deficit improved from abnormal baseline), and wLEMS (new postop deficit persistent at one year).
RESULT(S): A total of 733 patients were eligible, with 95 (12.96%) reporting neurologic complications (NC). Impact of any NC vs no complication at 1yr was significant for ODI (5.1), PCS (3.6) and SRSpain (0.2) at 1 year (p<0.001 all). For NC vs any other complication, there was still a decrease in ODI (3.9) and PCS (2.4) at 1 year (p<0.01). NC subtype: radiculopathy caused worse outcomes for (4.3) and SRS pain (0.3) (p<0.05), sensory deficit caused worse SRSmental (0.5) (p<0.05), but no HRQL change was detected for motor deficit at 1 year. PLEMS (456/733) had improvement in all HRQL, and these improvements were not different with or w/o NC, or non-NC. Compared to pLEMS w/o complication, dLEMS (62/733) and iLEMS (147/733) were statically similar, however wLEMS (68/733) had worse ODI (7.1), SRStotal (0.3), activity (0.3), mental (0.3), pain (0.3) (p<0.05 all).
CONCLUSION(S): Neurologic complications that occur following ASD have a significant effect on HRQLs. The magnitude of effect is driven by radiculopathy and by lower extremity motor score. LEMS scores that remain normal, return back to normal or improve have similar outcomes, while patients that have continued weakness remain statistically worse at 1 year. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: While advances have been made in the surgical management of distal junctional kyphosis (DJK), complication rates remain high. Although individual factors related to its occurrence have been cited, many of these cases are mild and have no clinical relevance nor have these been combined into a formal predictive model, particularly for cases that are clinically impactful. PURPOSE: Develop a formal predictive model distinguishing between symptomatic and asymptomatic DJK. STUDY DESIGN/SETTING: Retrospective review PATIENT SAMPLE: A total of 99 cervical deformity patients (CD) with 1 year (1Y) follow up OUTCOME MEASURES: Complications; reoperations; HRQL, alignment METHODS: CD patients (pts) were stratified into asymptomatic (Asym) and symptomatic (Sym) DJK. DJK angle (DJKA) was defined >10degree change in kyphosis between LIV and LIV-2 and a >10degree index angle. Asym: DJK to be>10degree in the absence neurologic sequelae. Sym: 1) DJKA> 10degree and either reop due to DJK or >one new-onset neurological sequelae related to DJK or 2) pts who had either a DJKA > 20degree or DJKA > 20degree. Stepwise logistic regressions were used to identify patient-specific, surgical, radiographic and HRQL factors that were associated with these types of DJK. Decision tree analysis established cut-offs for the continuous variables.
RESULT(S): A total of 99 CD pts were included (60yrs, 26.5kg/m2, 66.7%F). Surgical characteristics: 7.4+/-4 levels fused, 47.5% posterior, 18.2% anterior, and 34.3% combined. Overall, 32.2% developed DJK (34.3% Asym, 65.7% Sym). 37.5% of Asym pts received a reop vs 62.5% Sym pts. At BL, Asym pts had a greater BMI (28.5 vs 23kg/m2) and NSR back pain (5.2 vs 4.6; all p<0.05). Decision tree analysis identified osteoporosis, UIV level, and the apex of the region of the spine where the primary deformity is located to predict Sym pts. Top factors predicting Sym pts over Asym were BL EQ5D>0.65, UIV cephalad to C2, and C2-C7 apex caudal to C5. Multivariate analysis identified independent radiographic and surgical factors for developing Sym DJK: [Radiographic] BL PI (1.02[0.9-1.07]), preop cervical flexibility (1.04[1.01-1.07]); [Surgical] combined approach (6.2[1.4-27]; all p<0.05). Having abnormal hyper kyphosis in the thoracic spine, more so than abnormal cervical lordosis, was an independent factor for developing Sym when analyzed against Asym pts (1.2[0.01-115]). Predictive modeling identified factors that were predictive of Sym against no DJK pts such as having myelopathy (mJOA score:12-14), combined approach, UIV=C3 or C4, preoperative hypermobility, and >7 levels fused (AUC: 0.89). A predictive model for Sym versus Asym pts yielded an AUC of 85% and included being frail, having a TS-CL>20, and a PI>46.3. Controlling for BL deformity and disability, Sym pts had greater cSVA(4-8cm: 47.6%vs 27%) and were more maligned according to their SRS-SVA (0.1[0.76-0.02]) than non DJK pts at 1Y (all p<0.05). Despite their symptomatology and higher re-operation rate, outcomes equilibrated in the Sym cohort at 1Y following revision.
CONCLUSION(S): Overall 32.2% cervical deformed patients suffered from DJK most of which were clinically significant. Severe symptomatic DJK can be predicted with high reliability using combined determinants of baseline spinal cord dysfunction, mobility, frailty, and surgical factors including end levels, number of levels fused and use of a combined approach. It can be further distinguished from asymptomatic occurrences by taking into account pelvic incidence and baseline cervicothoracic deformity severity. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Opioid use prior to surgery is associated with worse postop outcomes. Little is known regarding the economic impact that preop opioid use has upon patient preferred health state, quality adjusted life years (QALYs) and the cost/QALY of surgical treatment for adult spinal deformity (ASD). PURPOSE: Compare the health state preference values, QALYs, and cost/QALY for operatively treated ASD patients that used opioids vs did not use opioids prior to surgery. STUDY DESIGN/SETTING: Cost/QALY analysis of operatively treated patients identified from a prospective, multi-center ASD study. PATIENT SAMPLE: Propensity score matched (PSM) cohorts of patients that used opioids (OPIOID) vs nonusers (NON) prior to ASD surgery, at 1- and minimum 2-year follow up. OUTCOME MEASURES: Short Form-36v2 questionnaire (SF-36), SF6D derived from SF-36, hospital costs for operative treatment of ASD based on CMS DRG reimbursements, QALYs, cost/QALY for index surgery, perioperative complications, and 1- and 2-year postop opioid use.
METHOD(S): ASD patients (age>18 years) enrolled into a prospective multicenter ASD database were divided into preop opioid (OPIOID) vs nonopioid (NON) users. PSM was performed to control for confounding demographic, radiographic, and surgical variables. Preop, 1-year, and minimum 2-year postop SF6D values obtained, 1- and 2-year post QALYs were calculated using SF6D change from baseline, hospital costs at the time of index surgery were calculated using CMS DRG reimbursements adjusted for inflation to 2019 US dollars, cost/QALY evaluated at 1- and 2-years postop, perioperative complications, and 1- and 2-year postop opioid use was evaluated for OPIOID vs NON.
RESULT(S): DRG data was available for 182/262 patients meeting inclusion criteria. Following PSM, preoperative demographics, radiographic parameters, surgical treatment, and mean follow up (3.4 vs 3.3 years) were similar for OPIOID (n=68) vs NON (n=114), respectively (p>0.05). OPIOID had longer ICU (49 vs 23 hours) and hospital stay (9.7 vs 6.8 days) than NON, respectively (p<0.05). SF6D was worse for OPIOID at preop (0.521 vs 0.598), 1-year (0.613 vs 0.749), and 2-years postop (0.626 vs 0.749) than NON, respectively (p<0.05). QALYs were worse at 1- (0.567 vs 0.674) and 2-years postop (0.674 vs 0.825) for OPIOID vs NON, respectively (p<0.05). Cost of care at index surgery was greater for OPIOID ($83,363.02) vs NON ($70,281.17). Cost/QALY was higher for OPIOID at 1-year ($150,294.51vs $107,947.19) and 2-years postoperative ($69,615.78 vs $48,761.14) than NON (p<0.05). Perioperative complications were similar for OPIOID vs NON (p>0.05). Continued opioid use at 2-years postop was greater for OPIOID (52.4%) vs NON (8.7%; p>0.05).
CONCLUSION(S): Opioid use prior to ASD surgery is associated with worse patient perceived health state and greater costs to society. After controlling for patient demographics, deformity magnitude, and type of surgery, OPIOID had greater cost of care, despite similar perioperative complication rates. At 2-years postop both OPIOID and NON demonstrated cost effectiveness of index surgery (cost/QALY<$100,000), however the residual cost to society was $21,300 greater for OPIOID vs NON. Over 52% of OPIOD had continued opioid usage at 2-years postop compared to 8.7% of NON. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Substantial adult spinal deformity (ASD) research has focused on sagittal plane radiological assessment and emphasized the importance of sagittal correction on patient-reported outcomes. It seems less attention has been given to evaluation of ASD in the coronal plane. However, recent ASD studies have demonstrated baseline global coronal malalignment (GCM; substantial displacement of the C7 coronal plumb line from midsacrum) in up to 35% of patients. Moreover, GCM can worsen postoperatively or may occur as an iatrogenic complication in previously balanced patients. Collectively, this may suggest that the associated clinical impact of GCM on ASD surgical outcomes has been underestimated. Currently, few reports focus on surgical outcomes in ASD patients with GCM. PURPOSE: Our objective was to assess treatment outcomes and complication rates associated with ASD surgery in the subset of patients with severe GCM. STUDY DESIGN/SETTING: Retrospective review of a prospectively collected multicenter consecutive case registry. PATIENT SAMPLE: Enrollment required: age >=18 years, scoliosis >=20degree, sagittal vertical axis (SVA) >=5cm, pelvic tilt >=25degree, and/or thoracic kyphosis >=60degree. OUTCOME MEASURES: Radiographic correction (both standard coronal and sagittal spinopelvic deformity measurements) and health-related quality of life (HRQL) outcomes, which included Oswestry Disability Index (ODI), Short Form-36 (SF-36) scores, Scoliosis Research Society-22 (SRS-22) scores, and back/leg pain numerical rating scale (NRS) scores.
METHOD(S): Surgically treated ASD patients with severe GCM (coronal C7PL-midsacral offset magnitude >=1 SD above the mean) were identified. Baseline and follow-up radiographic and HRQL outcomes were analyzed. Percentages of patients achieving minimal clinically important difference (MCID) and substantial clinical benefit (SCB) were assessed. Demographic, frailty, surgical, and complications data were collected. The primary focus for analysis was on patients who reached minimum 2-year follow-up.
RESULT(S): Of 691 potentially eligible operative patients (mean GCM = 4+/-3 cm), 80 met criteria for severe GCM >= 7cm. Of these 80 patients, 62 (78%, mean age 64 years, 81% women) had minimum 2-year follow-up. Baseline frailty score was 3.9+/-1.5 (indicating patients were frail) and 48% had prior spine fusion. Surgical data included: posterior-only (58%), mean fusion 13 levels, sacroiliac fixation (97%), and three-column osteotomy (36%). Postoperative biplane alignment improved significantly (p<0.001): GCM 11 to 4 cm, lumbar Cobb 30degree to 11degree, C7-S1 SVA 13 to 4 cm, and PI-LL 31degree to 5degree. Overall HRQL improved significantly (p<=0.003): ODI 51 to 37, SF-36 PCS 29 to 37, SRS-22r 2.6 to 3.5, and back/leg pain NRS 7 to 4 and 5 to 3, respectively. Thresholds for MCID/SCB were met in 43-83% of patients. A total of 89 complications were reported (34 minor/55 major), and 45 (73%) patients had >=1 complication (most commonly rod fracture [19%] and PJK [18%]). There were 34 reoperations in 22 (36%) patients (most common indications rod fracture/PJK). The 18 patients who did not achieve 2-year follow-up had a mean of 0.63 years follow-up, and the types of complications encountered in these 18 patients were comparable to those encountered in patients with 2-year follow-up.
CONCLUSION(S): ASD surgery for patients with severe GCM is associated with significant improvements in biplane alignment and HRQL outcome measures despite high complication rates. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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