Faculty Bibliography

BACKGROUND CONTEXT: The age-adjusted alignment ideal alignment was proposed in order reduce the occurrence of proximal junctional kyphosis (PJK) in an adult spinal deformity (ASD) population. The normative postoperative age ideal value for the mismatch between pelvic incidence and lumbar lordosis (PI-LL) has yet to be related to the global alignment and proportion (GAP) score postop proportionality. PURPOSE: To assess the impact of normative age-adjusted PI-LL and proportionality via GAP score on postoperative patient-reported outcomes. STUDY DESIGN/SETTING: Retrospective review of single-surgeon adult spinal deformity (ASD) database PATIENT SAMPLE: 140 ASD patients. OUTCOME MEASURES: Health-related quality-of-life (HRQLs); SRS-22r; PJK.
METHOD(S): ASD patients with baseline (BL) and 2-year postoperative (2Y) radiographic and HRQL data were included. Age-adjusted correction groups generated at postoperative follow-up for actual alignment compared to age-adjusted values for PI-LL-adjusted ideal values (matched, overcorrected, undercorrected). GAP Score in the literature includes the four parameters, and an age factor to formulate a sagittal plane score out of 13 (proportional, moderately disproportional [MD], severely disproportional [SD]). GAP improvement scores were noted as less at 2Y compared to BL. Patients were grouped by age-adjusted and 2Y GAP results: Match PI-LL/Proportional GAP, Match PI-LL/Disproportional GAP, Unmatch PI-LL/Proportional GAP, Unmatch PI-LL/Disproportional GAP. Means comparison and chi-squared ANOVA analyses assessed the outcomes between age-adjusted and GAP groups.
RESULT(S): Included: 140 ASD patients (55.5+/-16.4 years, 81% female, 25.2+/-4.7kg/m2). At BL, mean sacral slope: 30.7degree, pelvic tilt: 23degree, pelvic incidence: 53.5degree, PI-LL: 13.3degree, SVA: 61.6 mm, and L1-S1: 40.4degree. BL GAP proportionality: 17.8% proportional, 27.1% MD, 55% SD. PI-LL by baseline GAP proportionality groups: -6.4degree Proportional, -4.6degree MD, 26.8degree SD, p<0.001. Baseline ODI increased significantly with GAP proportionality: 27.3 Proportional, 32.3 MD, 37.4 SD, p=0.050. Assessment of 2Y age-adjusted PI-LL alignment found that 20.3% of patients Matched, 45.1% Overcorrected, and 34.6% Undercorrected. By 2Y GAP results, 32.3% were proportional, 38.5% MD, 29.5% SD (40.5% of patients improved, while 48.5% remained the same, and 11.1% deteriorated in their GAP proportionality). Categorized by the PI-LL age-adjusted/GAP groups: 2.3% Match PI-LL/Proportional GAP, 13.1% Match PI-LL/Disproportional GAP, 30% Unmatch PI-LL/Proportional GAP, 54.6% Unmatch PI-LL/Disproportional GAP. Patients who Unmatched PI-LL/Disproportional in GAP had significantly worse postoperative SRS-Pain scores (1.80 vs 3.53-3.86), SRS-Appearance (3.30 vs 3.69-4.29) and SRS-22 Total scores (2.84 vs 3.80-4.12), all p<0.050. Unmatch PI-LL/Disproportional patients developed PJK at a significantly higher rate by 6-months (66.7% vs 11.8-15.4%), p<0.050. Outcomes were not different between Match PI-LL/Disproportional GAP and Unmatch PI-LL/Proportional GAP groups.
CONCLUSION(S): Collectively over or undercorrecting in age-adjusted mismatch pelvic incidence and lumbar lordosis and becoming disproportional in spinal shape at 2 years led to increased postoperative proximal junctional kyphosis and significantly worse patient-reported outcomes. Surgeons should be wary of the double mal-correction when utilizing these complex realignment schemas. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Patient-specific, pre-contoured rods are increasingly used in the surgical treatment of spinal pathologies. Previous studies show that pre-contoured rods help to achieve desired postoperative alignment goals, though it is unclear whether these benefits differ by fusion length. PURPOSE: Assess how preoperative planning and patient-specific rods affect the outcomes of patients undergoing posterior cervical fusion surgery. STUDY DESIGN/SETTING: Retrospective review of single-center cases of multilevel posterior cervical surgeries from 2014-2018. PATIENT SAMPLE: This study included 65 patients. OUTCOME MEASURES: Sagittal alignment: cervical sagittal vertical axis (cSVA), cervical lordosis (CL), T1 Slope (T1S) minus CL (TS-CL), and cervical-thoracic pelvic angle (CTPA).
METHOD(S): Patients undergoing posterior cervical fusion with available pre- and postop (3-month, 6-month, or 1-year) cervical radiographs were stratified: those whose surgeries involved preoperative planning and patient-specific, pre-contoured rods (PLAN), and those whose surgeries did not (NON). Independent samples t-tests assessed differences between PLAN and NON groups in alignment, and pre- to postop changes in alignment. Secondary analysis assessed differences in alignment between PLAN and NON groups for patients with lower-most instrumented vertebrae (LIV) above C7-T1, and below.
RESULT(S): Included: 65 patients (55.1+/-9.9 years, 61% female) undergoing posterior cervical fusion (6.2+/-3.7 levels). Mean follow-up was 8.4+/-4.1 months. By group, 47.7% of patients had pre-contoured rods (PLAN, N=31), 53.3% did not (NON, N=34). Preoperatively, PLAN patients presented with greater cervical malalignment (CTPA: 4.0degree vs 2.7degree, p=0.015) and T1 Slope (33degree vs 22degree, p=0.013), but not global (SVA, TPA), or lumbopelvic alignment (PT, PI-LL, all p>0.05). Postoperatively, PLAN patients had greater C2-C7 lordosis than NON patients (18degree vs 7degree, p=0.001), and a trend of superior TS-CL alignment (19degree vs 23degree, p=0.075), but did not differ in any other cervical, global, or lumbopelvic parameters (all p>0.05). PLAN patients also showed superior pre- to postop changes in TS-CL (-7degree vs 2.1degree, p=0.026). Overall, 25% of patients had LIVs above C7-T1 (mean fusion length: 4.8+/-1.1 levels), while 75% had fusions extending lower (10.0+/-5.5 levels). For cases in which fusion extended below C7-T1, PLAN patients showed a trend of greater pre- to postop TS-CL correction (-3degree vs 3degree, p-0.076), more postop CL (14degree vs 6degree, p=0.007), and less lumbopelvic malalignment (PI-LL:-7.1degree vs 0.1degree, p=0.029) and (PT: 14degree vs 19degree, p=0.087), though this result is confounded by greater preop PI-LL and PT deformity for NON patients (both p<0.03). No such differences were observed between PLAN and NON groups for cases in which the LIV was above C7-T1 (all p>0.05).
CONCLUSION(S): For posterior cervical fusion cases, the use of preoperative planning and patient-specific, pre-contoured rods was associated with superior correction of cervical sagittal alignment. For cases in which fusion extended below C7-T1, use of contoured rods was associated with superior postop reciprocal alignment in the lumbopelvic spine, though this may be confounded by differences in preop alignment. For longer fusions, pre-planned and contoured rods may offer greater utility. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Prior studies have demonstrated potential benefits of adult spinal deformity (ASD) surgery, but less outcomes data exist for operative ASD patients with severe scoliotic curves (thoracic [TH] curve >=75degree, thoracolumbar [TL] curve >=50degree, or lumbar [LL] curve >=50degree). Also, the surgical complication profile is less clear for this subset of patients with severe scoliotic deformity and warrants focused investigation. PURPOSE: The objective of the current study was to assess treatment outcomes and complication rates associated with ASD surgery in patients with severe scoliosis. STUDY DESIGN/SETTING: Retrospective review of a prospectively collected multicenter consecutive case registry PATIENT SAMPLE: Enrollment required: age >=18 yrs, scoliosis >=20degree, sagittal vertical axis (SVA) >=5cm, pelvic tilt >=25degree, and/or thoracic kyphosis >=60degree. OUTCOME MEASURES: 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, and Scoliosis Research Society-22 (SRS-22) scores.
METHOD(S): Using a prospective multicenter database, we identified surgically treated ASD patients with severe scoliosis (TH Cobb >=75degree or TL/LL Cobb >=50degree) and minimum 2-yr follow-up. Demographic data, surgical characteristics, radiographic alignment measurements, HRQL outcomes and associated complications were analyzed.
RESULT(S): Of 178 patients, 146 (82%, mean age 54 yrs, 92% women, 88 TL, 50 LL, 8 TH) had minimum 2-yr follow-up (mean=3.1 yrs). Almost 30% had prior spine fusion, 6% were active or past smokers, 16% had osteoporosis and 77% had at least 1 comorbidity. Surgical details included: posterior-only (58%) or anterior-posterior approach (42%), SPO (65%), 3CO (14%), TLIF (23%), ALIF (37%), sacropelvic fixation (76%), upper thoracic UIV (64%) and mean posterior fusion length of 13.2 levels. Postoperative coronal alignment improved significantly for all patients (global coronal alignment 3.8 to 2.8 cm, p< 0.001; TH Cobb 38degree to 24degree, p<0.001; TL Cobb 61degree to 30degree, p<0.001; LL Cobb 50degree to 24degree, p<0.001; Fractional Cobb 20degree to 7degree, p<0.001). Overall sagittal alignment also improved significantly (p<0.05), most notably for severe lumbar curves (C7-S1 SVA 6.7 to 2.5 cm, p<0.001; PI-LL 18degreeto 3degree, p<0.001). Overall HRQL improved significantly, including ODI (39 to 26, p<0.001), SF-36 PCS (35 to 41, p<0.001) and SRS-22r (2.9 to 3.8, p<0.001). A total of 191 complications were reported (92 minor/99 major), and 94 (64%) patients had at least one complication. The most common complications included dural tear (12%), pleural effusion (12%), rod fracture (11%), radiculopathy (8%) and proximal junctional kyphosis (7%). 34 reoperations were performed in 27 (18%) patients, with most common indications of rod fracture/pseudarthrosis (8), deep wound infection (6) and neurological deficit (5).
CONCLUSION(S): Surgery for severe adult scoliosis is associated with significant improvement in radiographic alignment and HRQL measures. Although associated complication rates are high, these appear to be comparable to reports of less severe scoliosis. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Vascular stenting is a common intervention for patients afflicted with coronary artery disease. For elective spine fusion patients with a history of coronary artery disease, a stent provides a less invasive surgical intervention allowing patients to move forward with spinal surgery. However, the impact of an initially less invasive cardiac intervention on outcomes of future surgical spine procedures has been understudied. PURPOSE: Investigate effect of coronary stents on postoperative outcomes in an elective spine fusion cohort. STUDY DESIGN/SETTING: Retrospective review of the PearlDiver database between the years 2006-2013. PATIENT SAMPLE: A total of 726,061 elective spine fusion patients. OUTCOME MEASURES: Comorbidity burden, 30-day and 90-day complications (myocardial infarction, pneumonia, sepsis, death, would complications, transfusions), length of stay.
METHOD(S): Elective spine fusion patients were isolated with ICD-9 and CPT procedures codes in the PearlDiver database. Patients were stratified by number of coronary stents: (1) 1-2 stents (ST12); (2) 3-4 stents (ST34); (3) no stents. Means comparison tests compared differences in demographics, diagnoses, comorbidities, 30-day and 90-day complication outcomes. Logistic regression assessed the odds of complication associated with coronary stents, controlling for levels fused, age, sex, and comorbidities (odds ratio [95% confidence interval]). Statistical significance was set p<0.05.
RESULT(S): A total of 726,061 elective spine fusion patients were isolated; 707,396 patients had no stent, 17,087 ST12 and 1,578 ST34. At BL, ST12 patients had higher rates of morbid obesity, chronic kidney disease, CHF, COPD, and diabetes mellitus compared to no stent and ST34 (all p<0.001). Relative to no stent patients, ST12 patients had a greater LOS and at 30 days, significantly higher complication rates including pneumonia, myocardial infarction, sepsis, AKI, UTI, wound complications, transfusions, and 30-day readmission (p<0.05). Controlling for age, sex, comorbidities, and levels fused ST12 was a significant predictor of MI within 30 days (OR: 2.15[1.7-2.7], p<0.001) and 90-days postop (OR:1.87[1.6-2.2], p<0.001). ST34 patients compared to no stent at 30 days presented with increased complication rates such as pneumonia, MI, sepsis, UTI, wound complications, and 30-day readmissions. Regression analysis show no significant differences in complications between ST12 vs ST34 at 30 days, but at 90 days ST34 was associated with significantly increased rate and odds of death (1.1% vs 0.3%, p=0.021; OR:1.94 [1.13-3.13],p=0.01).
CONCLUSION(S): Cardiac stents failed to normalize risk profile of patients with coronary artery disease. Postoperatively at 90 days, elective spine fusion patients with 3 or more stents were significantly at risk of mortality compared to patients with fewer or no stents. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Revision surgery is often necessary for adult spinal deformity (ASD) patients. Satisfaction with management is an important component of HRQOL. PURPOSE: We hypothesized that patients who underwent multiple revision surgeries following adult spinal deformity correction would exhibit lower satisfaction scores. STUDY DESIGN/SETTING: Retrospective cohort study of a prospectively collected multicenter database of ASD patients. PATIENT SAMPLE: A total of 668 patients undergoing ASD surgery and eligible for minimum 2-year follow-up were included. OUTCOME MEASURES: SRS-22r satisfaction score.
METHOD(S): Visits were stratified by occurrence prior to the index surgery (period 0), after the index surgery only (period 1) (ie, never underwent revision or had not yet undergone revision), after first revision only (period 2), and after second revision only (period 3). Patients were further stratified by prior spine surgery before their index surgery. SRS-22r satisfaction scores were evaluated at all periods using multiple linear regression adjusting for age, gender, and CCI.
RESULT(S): In total, 46.6% had prior spine surgery before their index surgery. The overall revision rate was 21.3%. among patients with no spine surgery prior to the index surgery, satisfaction increased from period 0 to 1 (2.8 to 4.3, p<0.0001), decreased after one revision from period 1 to 2 (4.3 to 3.9, p=0.0004), and decreased after a second revision from period 2 to 3 (3.9 to 3.3, p=0.0437). Among patients with spine surgery prior to the index procedure, satisfaction increased from period 0 to 1 (2.8 to 4.2, p<0.0001), and decreased from period 1 to 2 (4.2 to 3.8, p=0.0011). No differences in follow-up time from last surgery were observed between visits in periods 1, 2, and 3 (all p>0.3). among patients with multiple revisions, 40% experienced rod fracture, 40% PJK, and 33% pseudarthrosis.
CONCLUSION(S): ASD patients exhibit decreased satisfaction with subsequent revision. Among patients undergoing primary surgery in our database, this effect is additive for multiple revisions. These results have important implications for surgeons, patients, insurers, hospital administrators, and policymakers. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Hospital acquired conditions (HACs) were established in the Affordable Care Act, and are defined as reasonably preventable complications that are nonreimbursable. In high risk patient populations for HACs, such as frail surgical spine patients, preoperative evaluation should consider modifiable factors. PURPOSE: To identify if optimizing the modifiable factors in the frailty index reduce the risk of developing HACs in population of surgical spine patients. STUDY DESIGN/SETTING: Retrospective cohort study. PATIENT SAMPLE: This study included 196,523 elective spine surgery patients in the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP). OUTCOME MEASURES: Modifiable patient frailty factors: hypertension and diabetes mellitus; rates of HACs, superficial or deep surgical site infection (SSI), deep venous thromboembolism (VTE) and urinary tract infection (UTI), across frailty scores.
METHOD(S): Patients >18 years who underwent elective spine surgery were identified in ACS-NSQIP database from 2005-2016. HACs identified: SSI, VTE, and UTI. Patient frailty was assessed utilizing the modified NSQIP 5-factor frailty index. The modified frailty score (mFI-5) is assessed on a scale between 0 and 1 (no frailty [NF] <0.3, mild frailty [MF] 0.3-0.5, severe frailty [SF] >0.5). Descriptive analysis quantified rates of patient characteristics, operative details, and HAC prevalence. Stepwise linear regression models determined significant predictors of baseline frailty using controllable patient factors. HACs were compared between 'optimized' and 'non-optimized' frailty status in the cohort. Level of significance was set to P<0.05.
RESULT(S): A total of 196,523 patients (57+/-14.2 years, 30.4 kg/m², 48%F) met inclusion criteria. Overall, 5,720 (2.9%) of patients developed an HAC, the most common was an SSI (1.3%), followed by UTI (1.1%). When stratified by the mFI-5 frailty severity groups at baseline, 83.6% of patients were categorized NF, 15.1% MF and 1.3% SF. Within the frailty severity groups, prevalence of overall HACs increased significantly (NF: 2.64%, MF: 4.17%, 5.93%, p<0.001). Rates of all individual postoperative HACs assessed also increased with greater baseline frailty severity: SSI (NF: 1.14%, MF: 1.93%, SF: 2.39%, p<0.001), UTI (NF: 0.91%, MF: 1.66%, SF: 2.85%, p<0.001), VTE (NF: 0.68%, MF: 0.80%, SF: 1.16%, p=0.002). Stepwise linear regression models determined that diabetes mellitus (beta = 0.493) and hypertension (beta = 0.679) were the most significant predictors for increased baseline frailty by way of the mFI-5 NSQIP index (Final model: R2= 0.897). Of total patients, 47.2% had the optimal modifiable frailty factors (no history of diabetes or hypertension). The optimal frailty patients had significantly less overall incidence of SSI (2.03% vs 2.5%, p<0.001), UTI (0.65% vs 1.4%, p<0.001), DVT (0.56% vs 0.84%, p<0.001), and any overall HAC (2.18% vs 3.56%, p<0.001).
CONCLUSION(S): Stepwise linear regression models determined that hypertension and diabetes account for 89.7% of variance in baseline mFI-5 score. Patients with these optimal controllable factors had reduced incidence of all hospital acquired conditions. In order to optimize hospital resources and treatment outcomes, physicians and patients should be aware of the modifiable factors that contribute to a patient's frailty that can ultimately impact acquiring HACs. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Cervical deformity (CD) severity has been linked to poor quality of life and severe neck pain. However, little is known of the relationship between surgical invasiveness accounting for cervical deformity severity and frailty status. PURPOSE: Investigate the outcomes of CD surgery by invasiveness, frailty status and baseline degree of deformity. STUDY DESIGN/SETTING: Retrospective cohort study. PATIENT SAMPLE: Ninety-six CD patients. OUTCOME MEASURES: HRQL measurements: NDI, EQ5D, mJOA.
METHOD(S): Inclusion criteria was defined as operative CD patients (C2-C7 Cobb>10degreeor CK>10degree, cSVA>4cm or CBVA>25degree) >18yr with follow up (1-year) radiographic and HRQL scores, NDI, mJOA and EQ5D. Patients were stratified by severity of deformity by TS-CL, categorized by the new-mJOA based modifiers: Low/Mod <45degree (Low-Mod); Severe >45degree(Sev). Frailty scores were calculated based upon the modified CD frailty index by Passias et. Al and categorized into severely frail (SF) >=0.5 and not SF (N-SF)<0.5. Patients were categorized by their frailty and deformity status (Low-Mod/N-SF; Low-Mod/SF; Sev/N-SF; Sev/SF). Logistic regression analysis assessed the relationship between increasing invasiveness and outcomes (DJK, complications). Within the significant frailty/deformity risk groups, decision tree analysis assessed thresholds for an invasiveness severity cut-off point, below which experiencing a reoperation, complication, DJK occurrence and poor mJOA were higher.
RESULT(S): Ninety-six CD patients met inclusion criteria (62.2+/-10.2 years, 66% female, 28.4+/-7.4 kg/m2). By approach: 19.8% anterior-only, 47.9% posterior-only, 32.3% combined (levels fused: 7.7+/-3.9). By deformity severity: 23.7% Low, 40.9% Moderate, 34.4% Severe, while frailty assessment placed 32.3% in N-SF and 67.7% SF. This categorized the patients into deformity/frailty groups as follows: 19.8% Low-Mod/N-SF(19), 13.5%(13) Sev/N-SF, 44.8%(43) Low-Mod/SF, 21.9%(21) Sev/SF. Logistic regression analysis found a significant relationship between increasing deformity severity and occurrence of severe postop DJK(1.053 [1.016-1.093], p= 0.005), complications(1.045 [1.012 - 1.080], p=0.007), revision by 1-year(1.059 [1.000-1.122], p= 0.049). Additionally, increasing invasiveness and occurrence of severe DJK (1.030 [1.007-1.054], p= 0.024) and revision (1.026 [1.008 - 1.044], p=0.005). Invasiveness increased with deformity and frailty severity: 53.6 Low-Mod/N-SF, 81.4 Sev/N-SF, 56.4 Low-Mod/SF, 79.8 Sev/SF; p=0.002. After defining a favorable outcome as no occurrence of severe DJK, no major complications and no revisions, and 1Y mJOA improvement (28.1%), invasiveness scores were compared within deformity/frailty groups between patients who met/did not meet the favorable outcome. For the NSF deformity groups, those with a favorable outcome had larger invasiveness scores (Low-Mod: 58.7 vs 48.5; Sev: 77.7 vs 89.6). For the SF deformity groups, the favorable outcome had significantly lower invasiveness scores for the Low-Mod deformity group (38.1 vs 62.9, p=0.008), while the Sev/SF deformity favorable outcome group remained larger (86.8 vs 79.4), though this was not significant. For the Low-Mod/SF group an invasiveness cutoff score of <48 where achieving a favorable outcome was 3x higher (3.08[1.2-7.9], p=0.019).
CONCLUSION(S): For SF patients, when deformity severity is low to moderate, surgeons may limit the invasiveness of their procedures in order to account for the patient's susceptibility to poor outcomes. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Distal junctional kyphosis (DJK) is a radiographic finding identified after patients undergo instrumented spinal fusions which can lead to decreased mobility in the affected spinal segments. There is a lack of consensus of the true etiology of DJK, since it is multifactorial in nature. PURPOSE: Develop a novel risk index specific to each patient to minimize postoperative DJK occurrence using distal construct and surgical factors STUDY DESIGN/SETTING: Retrospective review of a single-center comprehensive CD database PATIENT SAMPLE: A total of 110 CD patients (pts) OUTCOME MEASURES: DJK, Health Related Quality of Life, Reoperation, Minimal Clinically Important Difference (MCID) EQ5D.
METHOD(S): CD pts with BL and at least 1Y radiographic parameters were included. A patient-specific DJK score was created through use of unstandardized Beta weights of a multivariate regression model predicting DJK (end of fusion construct to the 2nd distal vertebra change in this angle by <-10degree from BL to postop). The equation consisted of distal construct factors [A) BL-3M inclination angle, B) BL inflection point, C) LIV angle,] and surgical factors [D) combined approach, E) TS-CL, F) PT, G) C2-C7, H) T4-T12, I) osteoporosis]. A BL model was created as a reference that included all of the above factors not including (C2-C7 and T4-T12). Correlations with 2Y outcomes was identified with use of this BL reference score.
RESULT(S): A total of 110 CD pts included (61yrs, 66.4%F, 28.8kg/m2). Of these, 31.8% pts developed DJK (16.1% 3M, 11.4% 6M, 62.9% 1Y). At BL DJK pts were more frail, had more combined approaches, and had more anterior approaches (all p<0.05). Multivariate model regression analysis identified individualized scores through creation of a DJK equation: 1.15+ 0.04 (Inclination) -2.3 (Preinflection) + 0.04 (LIV angle) + 0.78 (combine approach) + 0.09 (TS-CL) + 0.02 (PT) + 0.11 (C2-C7) + 0.02 (T4-T12) + 0.12 (osteoporosis). This equation (min: 0007 and a max: 95.3) has an 86.3% accuracy of predicting DJK. Having a score>81 predicted DJK with an accuracy of 89.3%. The BL reference equation, (-1.3+0.002 [BL inclination score]-1.3 [BL inclination C6 to T1]-0.05 [BL LIV angle] +1.4 [combined approach] + 0.01 [BL PT]-0.023 [osteoporosis]), correlated with 2Y outcomes of NSR-back percentage(p=0.003), reoperation(p=0.04) and MCID for EQ5D(p=0.04).
CONCLUSION(S): This study created a newly proposed risk index that focuses heavily on distal construct and surgical factors. Having a DJK score >81 was associated with an increase in risk of DJK. The reference models created were identified to correlate with 2-year outcomes of NSR-back percentage, reoperation rates and minimal clinically importance difference for EQ5D. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Amidst a current US opioid epidemic, it is important to understand factors that contribute to long-term or sustained opioid use after elective spine surgery. Recent reports have reported up to 25% of opioid-naive patients are taking opioids at 2-year follow-up after adult spinal deformity (ASD) surgery. This suggests ASD surgery, or at least the postoperative course, could be a significant factor contributing to long-term or sustained opioid use. ln Asian countries, opioids are rarely prescribed for postoperative pain. Potentially, there is a significant cultural difference that can play a role in patient expectations in the postoperative period leading to long-term opioid use. PURPOSE: To compare long-term or sustained (2-years) opioid use after ASD surgery between American and Japanese Cohorts STUDY DESIGN/SETTING: Propensity-matched comparison of American and Japanese ASD patients PATIENT SAMPLE: Patients from two (United States vs Japanese) prospective, multicenter ASD databases were compared OUTCOME MEASURES: Baseline and 2-year opioid use and SRS-22 domains were compared METHODS: We propensity matched 127 JPN to 619 US ASD patients based on age, sex, BMI, 3-column osteotomy, pelvic fixation, number of levels fused and preoperative SVA. Pre-op and 2-year postoperative opioid use was determined using responses to SRS22R Q11 and grouped into 3 categories (none, weekly, or daily). We have previously validated the use of SRS22R Q11 as an accurate measure for opioid use by comparing to a prospective study specifically designed to study opioid use and postoperative outcomes in ASD.
RESULT(S): From each cohort, 34 cases were successfully matched, with no difference in baseline parameters, including baseline opioid use (p=0.095), between the cohorts. The relatively low numbers in each cohort arise from difficulty matching a lower BMI and lower baseline opioid use in the JPN cohort. At 2-years postop, 22 US (65%) vs 31 JPN (91%) reported no opioid use, 1 US (3%) vs 0 JPN (0%) reported weekly use, and 11 US (32%) vs 3 JPN (9%) reported daily use (p=0.009). There was no difference in 2-year SRS-22 Self-image and Mental Health between the two groups while US patients had better Satisfaction (4.29 vs 3.84, p=0.032) but lower Function scores (3.52 vs 3.90, p=0.029).
CONCLUSION(S): In propensity-matched ASD cohorts, 35% of US patients were still using opioids 2 years after surgery compared to 9% of JPN patients, with the most taking opioids daily. Further studies are needed to identify sources of this variability. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Traditional iliac (IS) and S2-alar-iliac (S2AI) pelvic fixation methods have unique technical characteristics in their application, and result in varied biomechanical and anatomic impact. These differences may lead to variance in lumbopelvic fixation failure types and rates. PURPOSE: We intended to evaluate the influence of type of iliac fixation utilized for adult spinal deformity (ASD) correction on the frequency and manner of lumbopelvic fixation failure. STUDY DESIGN/SETTING: Retrospective review of prospective, multicenter ASD database. PATIENT SAMPLE: This study included 410 patients. OUTCOME MEASURES: HRQL (ODI, SF-36, NRS), rod fracture, screw fracture, screw loosening, revision surgery, pseudarthrosis METHODS: Inclusion criteria included ASD (coronal Cobb>=20degree, sagittal vertical axis (SVA) >=5cm, pelvic tilt >=25degree and/or thoracic kyphosis >60degree) >= 18 years old, 2yr follow-up, and >5 level fusion with pelvic fixation. Cohort subdivided by type of pelvic fixation (IS vs S2AI). Loosening was defined by lucency around the screw shank on radiographs. Univariate testing was performed using t-tests and chi-squared tests. Multivariate logistic regression, accounting for significant confounders, was used to examine differences between the two groups for screw loosening/fracture, rod fracture, and revision surgery. Level of significance = p<0.05.
RESULT(S): Of the total of 1422 patients, 410 met inclusion criteria (IS=287, S2AI=131). The two groups had similar age, BMI, baseline co-morbidities, and number of levels fused (p>0.05), as well as similar baseline HRQLs (SF-36, ODI, SRS-22, NRS leg and back, p>0.05) and deformity (PT, PI-LL, SVA, p>0.05). Patients in the IS group had a higher proportion of unilateral fixation compared to S2AI group (12.9% vs 5.6%; p=0.001). The overall pelvic fixation failure rate (screw loosening/screw fracture/rod fracture) was 29.4%. Loosening of pelvic fixation occurred in 13.4% of patients, and was more prevalent in the S2AI fixation group (OR 2.74, p=0.001). The rate of S1 screw loosening was 2.9%, and more likely to occur in the S2AI group (OR 4.17, p=0.045). The rate of pelvic fixation fracture in the overall cohort was 2.3%, with no difference between groups (p=0.37). Rod fracture occurred in 14.1% below L4, with a trend toward less occurrence in the S2AI group (OR 0.47, p=0.06). Revision surgery was required in 22.7% of our cohort, with no difference between groups (p=0.449). Patients with failure of the pelvic fixation had less improvement in their HRQL at 2years (PCS 7.69 vs 10.46 p=0.028; SRS 0.83 vs 1.03 p=0.019; ODI 12.91 vs 19.77 p=0.0016).
CONCLUSION(S): Pelvic fixation is commonly used in long segment adult spinal deformity surgery to improve the rate of L5-S1 fusion and protect from construct failure at the lumbosacral junction. Our results demonstrate a substantial rate of pelvic fixation hardware issues following ASD correction. Lumbopelvic fixation failure occurred at a rate of 29.4% following surgical correction of ASD that involved iliac fixation and was associated with diminished clinical outcomes. Additionally, S2AI screws were more likely to demonstrate loosening, but less commonly associated with rod fractures. Patients who experienced failure of their pelvic fixation had less improvement in their HRQL two years postoperatively. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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