Faculty Bibliography

BACKGROUND CONTEXT: Returning to full-time work postoperatively is important to employed adults undergoing surgical treatment of adult spinal deformity (ASD). It is important for both patients and providers to have realistic expectations of returning to work after surgery, and to understand the extent to which more invasive surgery may modify a patient's return to work. PURPOSE: Our purpose was to identify the frequency of employed ASD patients who are working full-time postoperatively, and the impact of surgical invasiveness on the percentage of patients who are working full time postoperatively at various time points. STUDY DESIGN/SETTING: Retrospective review of a prospective, multicenter database. PATIENT SAMPLE: A total of 255 ASD patients were identified in a multicenter database who were employed prior to surgery and eligible for 2-year follow-up. Of these patients, 188 (74%) had 2-year follow-up or returned to work at any point within 2 years postoperatively and were included in the final cohort. OUTCOME MEASURES: Our primary outcome was returning to full-time work following surgery.
METHOD(S): Working full-time was defined as reporting 75-100% of normal work/school activity per question 9 of the Scoliosis Research Society Version 22-revised (SRS-22r) questionnaire. Surgical invasiveness was measured according to the ASD Surgical and Radiographical (ASD-SR) invasiveness index, a tool that has been developed and validated to measure the invasiveness of ASD surgery. Patients were separated into high invasiveness (HI) or low invasiveness (LI) groups for ASD-SR scores above and below 100, respectively based on previously established invasiveness categories. Chi-squared and fisher exact test were used to compare categorical variables.
RESULT(S): Mean age of patients was 51 +/- 15 years of age, 79% females. Overall, 69% of these employed patients were working full-time preoperatively, 15% were working full-time at 6-weeks, 70% at 6 months, 83% at 1-year and 84% at 2-years. The percentage of patients working full time was significantly improved at 2-years compared to preoperatively (p<0.001). The difference in patients returning to full-time work in HI and LI groups was significantly different at 6-weeks (5% in high invasiveness vs 19% with low invasiveness, p=0.03), and this difference decreased to non-significant levels at 6-months, 1-year and 2-years (p>0.05).
CONCLUSION(S): The majority of employed adults will return to full-time work following ASD surgery. More patients are working full time at 2-years postoperatively compared to preoperatively, and patients with higher invasiveness surgery may have a delay in return-to-work in the immediate postoperative period. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
Copyright

BACKGROUND CONTEXT: The Miller et al adult spinal deformity frailty index (ASD-FI) correlates with increased complication risk after surgery; however, its development was not rooted in clinical outcomes, and the 40 factors needed for its calculation limit the index's utility in a clinical setting. PURPOSE: Develop a simplified, weighted frailty index for ASD patients. STUDY DESIGN/SETTING: Retrospective review of prospective ASD database. PATIENT SAMPLE: A total of 50 ASD patients. OUTCOME MEASURES: Health-related quality of life questionnaires: Oswestry Disability Index (ODI), SRS-22r, pain catastrophizing scale, Numerif Rating Scale (NRS) for Leg Pain.
METHOD(S): ASD patients (scoliosis>=20degree, SVA>=5cm, PT>=25degree, or TK >=60degree) with baseline ASD-FI component factors. Component ASD-FI parameters contributing to overall ASD-FI score were assessed via Pearson correlation. Top significant, clinically relevant factors were regressed against ASD-FI score to generate the modified ASD-FI (mASD-FI). Factors comprising the mASD-FI were regressed against the incidence of medical complications; weights for mASD-FI factors were calculated from these regression coefficients via the beta/Sullivan method. Total mASD-FI score was calculated by summing weights of expressed parameters, resulting in a score ranging from 0 to 21. Linear regression correlated ASD-FI and mASD-FI scores, and previously published ASD-FI cutoffs were used to generate corresponding mASD-FI frailty cutoffs: not frail (NF,<7), frail (7-12), severely frail (SF,>12). Analysis of variance assessed the relationship between increasing frailty category and validated baseline measures of patient pain and disability.
RESULT(S): Included: 50 ASD patients (52+/-20yrs, 78% female). All the following preoperative factors correlated with ASD-FI score (all p<0.039), and combined, accounted for 85.0% (p<0.001) of the variation in ASD-FI score: BMI <18.5 kg/m2 or >30 kg/m2 (weight: 5), depression (weight: 5), difficulty climbing stairs (3), presence of >3 medical comorbidities (2), leg weakness (2), difficulty getting dressed (1), bladder incontinence (1), and patient-reported deterioration in health within the past year (1). These factors were used to calculate the overall population's mean mASD-FI score: 5.7+/-5.2. Combined, these factors comprising the mASD-FI showed a trend of predicting the incidence of medical complications (Nagelkerke R2=0.558, Cox & Snell R2=0.399, p=0.065). Overall patient breakdown by mASD-FI frailty category: NF (70%), frail (12%), SF (18%). Increasing frailty category was associated with significant impairments in validated measures of disability, including ODI score (NF: 23.4, frail: 45.0, SF: 49.3, p<0.001), SRS-22r score (NF: 3.5, frail: 2.6, SF: 2.4, p=0.001), pain catastrophizing scale score (NF: 41.9, frail: 32.4, SF: 27.6, p<0.001), and NRS Leg Pain (NF: 2.3, frail: 7.2, SF: 5.6, p=0.001).
CONCLUSION(S): This study modifies an existing ASD frailty index and proposes a weighted, shorter mASD-FI. The mASD-FI relies less on patient-reported variables, and weights component factors by their contribution to adverse outcomes. As increasing mASD-FI score is associated with inferior clinical measures of pain and disability, the mASD-FI may serve as a valuable tool for preoperative risk assessment. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
Copyright

BACKGROUND CONTEXT: Chronic opioid use is an emergent public health issue in the United States. Opioids are regularly prescribed to patients with adult spinal deformity (ASD) for postoperative pain. Therefore, the potential for chronic postoperative opioid use is a significant concern for patients undergoing surgery for ASD. It is important to patients, surgeons and policymakers to understand preoperative risk factors for prolonged opioid use in ASD patients who were not using opioids regularly prior to surgery. PURPOSE: To demonstrate demographic and surgical factors associated with increased risk of chronic opioid use following surgery in ASD patients who were not regularly using opioids preoperatively. STUDY DESIGN/SETTING: Retrospective review of a multicenter database. PATIENT SAMPLE: A total of 760 ASD patients were identified in a multicenter database eligible for 2-year follow-up. Of these patients, 547 (72%) had complete baseline and 2-year responses to question 11 of the Scoliosis Research Society version 22r (SRS-22r), which allowed us to categorize patients into opioid users and non-opioid users. Of these, 251/547 patients (46%) were not using opioids regularly prior to surgery and included in our analysis. OUTCOME MEASURES: Our primary outcome was chronic postoperative opioid use, and secondary outcome was patient satisfaction.
METHOD(S): Among patients who were not using opioids regularly prior to surgery, those reporting routine opioid use at 1 or 2-year follow-up were classified as CU (chronic user), while patients reporting no opioid use at both 1 and 2 years after surgery were classified as NC (no chronic use). Odds of CU vs NC were examined in relation to factors of interest, controlling for history of previous substance use disorder and baseline radiographic deformity. Satisfaction was assessed using the satisfaction domain of the SRS-22r.
RESULT(S): Mean age of patients was 55 +/- 17 years, 78% females. Overall, patients were using opioids until 3.2 +/- 7.7 months postoperatively. A total of 176 patients (78%) were classified as NC and 51 (22%) CU. Factors associated with significantly increased odds of CU compared with NC included smoking (OR 3.44, 95% CI: 1.06 - 11.11; p=0.039), and each additional point worse on the back pain Numeric Rating Scale (NRS) (OR 1.24, 95% CI: 1.06 - 1.46; p=0.008) SRS-22r Activity domain (OR 1.99, 95% CI: 1.27 - 3.09; p=0.002) and SRS-22r Mental Health domain (OR 1.50, 95% CI: 1.06 - 2.11; p=0.022). Notable factors that were not significantly associated with chronic use included gender, C7-S1 sagittal vertical axis, prior spine surgery, elderly age, number of levels fused, 3-column osteotomy and at least one major complication (p>0.05). CU had worse SRS-22r satisfaction scores at 2 years compared with NC (4.33 +/-.93 vs 3.80 +/- 0.17, p=0.001).
CONCLUSION(S): The majority of opioid nonusers prior to ASD surgery will not become chronic users following surgery. Factors associated with chronic opioid use include smoking, higher baseline back pain, worse preoperative functional status, and worse mental health. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
Copyright

BACKGROUND CONTEXT: While corrective procedures for cervical deformity (CD) have significantly advanced, little is known what impact neurologic sequlae have on the postoperative recovery process. PURPOSE: Investigate which neurologic complications affect clinical outcomes the most following CD surgery. STUDY DESIGN/SETTING: Retrospective review of a prospective multicenter adult cervical deformity database. PATIENT SAMPLE: A total of 66 operative adult CD patients. OUTCOME MEASURES: Neurologic complication rates and Integrated Health State for the Neck Disability Index (NDI), EuroQol-5D (EQ-5D), and the Modified Japanese Orthopedic Association score (mJOA).
METHOD(S): CD patients (C2-C7 Cobb>10degree, CL>10degree, cSVA>4cm, or CBVA>25degree)>18yr with follow up surgical and HRQL data were included. Descriptive analyses assessed demographics. Neuro comps assessed were: C5 motor deficit, central neuro deficit, nerve root motor deficits, nerve sensory deficits, radiculopathy and spinal cord deficits. Neuro comps were classified as major (M) or minor, then: intra-operative, before discharge, before 30 days, before 90 days, and after 90 days. The rates of persistent neurologic deficits were assessed at 1 and 2 years. HRQL outcomes were assessed at 3M, 6M, 1Y and 2Y. Integrated health state (IHS) for the NDI, EQ5D, and mJOA were assessed using all follow up time points.
RESULT(S): A total of 66 operative CD patients were included. Baseline demo and surgery data: 61 years old, 63% female, BMI 29.7, op time 531.6 +/- 275.5, EBL 924.2 +/- 729.5, 49% posterior only approach, 18% anterior only approach, 33% combined. 34 (21%) patients experienced a total of 31 neurologic complications in the postoperative period (15M). In total, there were 7 radiculopathy, 6 motor deficits, 6 sensory deficits, 5 C5 motor deficits, 2 central neuro deficits, 2 spinal cord deficits, and 2 other. Motor deficits were the most common major complication (8), 4 of which were C5. Of the intraoperative complications, there were 3M, while 23% of patients had complications before discharge (5M). A total of 39% of neurologic complications occurred before 30 days (7M) and 71% before 90 days (12M), 16% were after 90 days (2M). A total of 12% of neuro comp patients went on to have revision surgery within 6 months, and 18% within 2 years. While normalized 6M mJOA scores were worse between neuro comp and no comp patients (1.00 +/- 0.12 vs 1.11 +/- 0.19, p=0.024), there was no significant difference in 2Y IHS for the NDI, EQ5D or mJOA (all p>0.05). When assessing individual comps, central neurologic deficits and spinal cord deficit patients had the worst outcomes at 1Y (2.6 and 1.8 times worse normalized NDI scores, p=0.04, no improvement in EQ5D, 8% decrease in EQ5D). Patients with sensory deficits had the best NDI and EQ5D outcomes at 1Y (31% decrease in NDI, 8% increase in EQ5D). One-half of neuro comp patients had persistent neurologic deficits at 1Y, and 21% at 2Y, however, there was no difference in outcomes at any time point (all p>0.05). Experiencing a nerve sensory deficit or spinal cord deficit correlated with revision surgery (r=0.241, 0.283, p<0.05).
CONCLUSION(S): A total of 21% of patients undergoing CD surgery experienced a neurologic complication, with 71% occurring within 6 months. While patients who experienced any neurologic complication had worse mJOA scores at 6M, there was no significant difference in recovery kinetics at 2Y. Of the neurologic complications, central neurologic deficits and spinal cord deficits were the most detrimental. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
Copyright

BACKGROUND CONTEXT: Cervical deformity (CD) correction is becoming more challenging and complex. Understanding the factors that drive optimal outcomes has been understudied in CD corrective surgery. PURPOSE: To weight baseline factors on impact upon outcomes following CD surgery. STUDY DESIGN/SETTING: Retrospective review of a single-center database. PATIENT SAMPLE: A total of 61 cervical patients. OUTCOME MEASURES: Two outcomes were measured: 'improved outcome'(IO):(1) radiographic improvement: 'non-deformed' Schwab PT/SVA, Ames cSVA/TS-CL, (2) clinical: MCID EQ5D, NDI, or improve in mJOA modifier, (3) complications/reop: no reop or major complications; 'poor outcome'(PO):(1) radiographic deterioration: 'moderate' or 'severely' deformed Schwab SVA/PT, Ames cSVA/TS-CL, (2) clinical: not meeting MCID EQ5D, NDI worsening in mJOA modifier; (3) complications/reop: reoperation or complications.
METHOD(S): CD patients included: full baseline (BL) and 1-year (1Y) radiographic measures and HRQLs. Reoperation for infection excluded. Patients were categorized by IO, PO or not. Random forest assessed ratios of predictors for IO and PO. Categorical regression models predicted how BL regional deformity (Ames cSVA, TS-CL, horizontal gaze), BL global deformity (Schwab PI-LL, SVA, PT), regional/global change (BL to 1Y), BL disability (mJOA score) and BL pain/function impact outcomes.
RESULT(S): A total of 61 patients were included (55.8yrs, 54.1% F). Surgical approach: 18.3% anterior, 51.7% posterior, 30% combined. Avg levels fused: 7.7. Mean operative time: 823min, EBL:1037ccs. At 1Y, 24.6% had an IO, 9.8% PO. Random forest analysis showed the top 5 individual factors associated with an IO: BL Maximum Kyphosis, Maximum Lordosis, C0-C2, L4 Pelvic Angle, and NSR Back Pain (80% radiographic, 20% clinical). Categorical IO regression model (R2=0.328,p=0.007): low BL regional deformity (beta=-0.082), low BL global deformity (beta=-0.099), global improve (beta=0.532), regional improve (beta=0.230), low BL disability (beta=0.100), low BL NDI (beta=0.024). Random forest demonstrated of the top 5 individual baseline factors associated with PO, 80% were radiographic: BL CL Apex, DJK angle, cervical lordosis, T1 slope and NSC Neck Pain. Categorical PO regression model (R2=0.306,p=0.012): high BL regional deformity (beta=-0.108), high BL global deformity (beta=-0.255), global decline (beta=0.272), regional decline (beta=0.443), baseline disability (beta=-0.164), BL severe NDI (>69)(beta=0.181).
CONCLUSION(S): Categorical weight demonstrated radiographic as the strongest predictor of both improved (global alignment) and poor outcome (regional deformity/deterioration). Radiographic factors carry the most weight in determining an improved or poor outcome, and can be ultimately utilized in preoperative planning and surgical decision-making in order to optimize outcomes. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
Copyright

OBJECTIVE:Obesity, a condition that is increasing in prevalence in the United States, has previously been associated with poorer outcomes following deformity surgery, including higher rates of perioperative complications such as deep and superficial infections. To date, however, no study has examined the relationship between preoperative BMI and outcomes of deformity surgery as measured by spine parameters such as the sagittal vertical axis (SVA), as well as health-related quality of life (HRQoL) measures such as the Oswestry Disability Index (ODI) and Scoliosis Research Society-22 patient questionnaire (SRS-22). To this end, the authors sought to clarify the relationship between BMI and postoperative change in SVA as well as HRQoL outcomes. METHODS:The authors performed a retrospective review of a prospectively managed multicenter adult spinal deformity database collected and maintained by the International Spine Study Group (ISSG) between 2009 and 2014. The primary independent variable considered was preoperative BMI. The primary outcome was the change in SVA at 1 year after deformity surgery. Postoperative ODI and SRS-22 outcome measures were evaluated as secondary outcomes. Generalized linear models were used to model the primary and secondary outcomes at 1 year as a function of BMI at baseline, while adjusting for potential measured confounders. RESULTS:Increasing BMI (compared to BMI < 18) was not associated with change of SVA at 1 year postsurgery. However, BMIs in the obese range of 30 to 34.9 kg/m2, compared to BMI < 18 at baseline, were associated with poorer outcomes as measured by the SRS-22 score (estimated change -0.47, 95% CI -0.93 to -0.01, p = 0.04). While BMIs > 30 appeared to be associated with poorer outcomes as determined by the ODI, this correlation did not reach statistical significance. CONCLUSIONS:Baseline BMI did not affect the achievable SVA at 1 year postsurgery. Further studies should evaluate whether even in the absence of a change in SVA, baseline BMIs in the obese range are associated with worsened HRQoL outcomes after spinal surgery.

BACKGROUND CONTEXT/BACKGROUND:The postoperative recovery patterns of cervical deformity patients, thoracolumbar deformity patients, and patients with combined cervical and thoracolumbar deformities, all relative to one another, is not well understood. Clear, objective benchmarks are needed to quantitatively define a "good" versus a "bad" postoperative recovery across multiple follow-up visits, varying deformity types, and guide expectations. PURPOSE/OBJECTIVE:To objectively define and compare the complete 2-year postoperative recovery process amongst operative cervical only, thoracolumbar only, and combined deformity patients using area-under-the-curve (AUC) methodology. STUDY DESIGN/SETTING/METHODS:Retrospective review of two prospective, multicenter adult cervical and spinal deformity databases. PATIENT SAMPLE/METHODS:170 spinal deformity patients OUTCOME MEASURES: Common health-related quality of life (HRQOL) assessments across both databases included the EuroQol 5-Dimension Questionnaire (EQ5D) and Numeric Rating Scale (NRS) back pain assessment. In order to compare disability improvements, the Neck Disability Index (NDI) and the Oswestry Disability Index (ODI) were merged into one outcome variable, the ODI-NDI. Both assessments are gauged on the same scale, with minimal question deviation. Sagittal Radiographic Alignment was also assessed at pre- and all post-operative time points. METHODS:Operative deformity patients >18 years old with baseline (BL) to 2-year HRQOLs were included. Patients were stratified by cervical only (C), thoracolumbar only (T), and combined deformities (CT). HRQOL and radiographic outcomes were compared within and between deformity groups. AUC normalization generated normalized HRQOL scores at BL and all follow-up intervals (6 weeks, -3 months, 1year, 2 year). Normalized scores were plotted against follow-up time interval. AUC was calculated for each follow-up interval, and total area was divided by cumulative follow-up length, determining overall, time-adjusted HRQOL recovery (Integrated Health State, IHS). Multiple linear regression models determined significant predictors of HRQOL discrepancies amongst deformity groups. RESULTS:0.177, p=0.039). CONCLUSIONS:Despite C patients exhibiting a quicker rate of MCID disability (ODI-NDI) improvement, they exhibited a poorer overall recovery of back pain with worse NRS back scores compared to baseline status and other deformity groups. Postoperative distal junctional kyphosis and osteoporosis were identified as primary drivers of a poor postoperative NRS back IHS. Utilization of the IHS, a single number adjusting for all postoperative HRQOL visits, in conjunction with predictive modelling may pose as an improved method of gauging the effect of surgical details and complications on a patient's entire recovery process.

Background/UNASSIGNED:Regional and segmental changes of the lumbar spine have previously been described as patients transition from standing to sitting; however, alignment changes in the cervical and thoracic spine have yet to be investigated. So, the aim of this study was to assess cervical and thoracic regional and segmental changes in patients with thoracolumbar deformity versus a nondeformed thoracolumbar spine population. Methods/UNASSIGNED:This study was a retrospective cohort study of a single center's database of full-body stereoradiographic imaging and clinical data. Patients were ≥ 18 years old with nondeformed spines (nondegenerative, nondeformity spinal pathologies) or thoracolumbar deformity (ASD: PI-LL > 10°). Patients were propensity-score matched for age and maximum hip osteoarthritis grade and were stratified by Scoliosis Research Society (SRS)-Schwab classification by PI-LL, SVA, and PT. Patients with lumbar transitional anatomy or fusions were excluded. Outcome measures included changes between standing and sitting in global alignment parameters: sagittal vertical axis (SVA), pelvic incidence minus lumbar lordosis (PI-LL), pelivc tilt (PT), thoracic kyphosis, cervical alignment, cervical SVA, C2-C7 lordosis (CL), T1 slop minus CL (TS-CL), and segmental alignment from C2 to T12. Another analysis was performed using patients with cervical and thoracic segmental measurements. Results/UNASSIGNED: = .009) segments. Conclusions/UNASSIGNED:Nondeformity patients and ASD patients have significant differences in mobility of global spinopelvic parameters as well as segmental regions in the cervical and thoracic spine between sitting and standing. This study aids in our understanding of flexibility and compensatory mechanisms in deformity patients, as well as the possible impact on unfused segments when considering deformity corrective surgery.