Faculty Bibliography

BACKGROUND CONTEXT: Reciprocal changes in cervical alignment occur with incremental degrees of adult spinal deformity (ASD) severity, or across different sagittal morphotypes as described respectively by Schwab and Roussouly systems. The extent to which these systems relate changes in the upper cervical spine remains underexplored. PURPOSE: To investigate quantitative anatomical relationships with regards to abnormal alignment in the upper cervical spine. STUDY DESIGN/SETTING: Retrospective review of a prospective multicenter ASD database. PATIENT SAMPLE: A total of 343 patients who met criteria for ASD. OUTCOME MEASURES: Cervical alignment parameters (C2-C7 angle, C2 slope, McGregor's Slope, CBVA when available, segmental tilt), Ostrow Disability Index (ODI) METHODS: Patients >18 years with ASD (scoliosis>=20degree, SVA>=5cm, PT>=25degree, or thoracic kyphosis >=60degree) and complete radiographic data at baseline (BL) & 1-year (1Y) were identified. Patients were grouped by BL PI and apex of LL into component types of the Roussouly classification system (Type 1: PI<45degree & LL apex below L4; Type 2: PI<45degree & LL apex above L4; Type 3: 45degree65degree). Patients were categorized by increasing severity of SRS-Schwab modifiers at BL (0, +, ++) and further grouped by anatomical malalignment, moving cranially (P: pelvic only; LP: lumbopelvic; TL: thoracolumbopelvic; C: subaxial & thoracolumbo-pelvic). Analysis of variance (ANOVA) tests assessed differences in BL upper cervical alignment parameters (C0-C2, C0 slope, McGregor's slope, CBVA) and ODI scores across Roussouly and Schwab modifier groups.
RESULT(S): A total of 343 ASD patients were analyzed. Schwab modifiers at BL were as follows: SVA (0: 45.8%, +: 20.3%, ++: 33.9%), PI-LL (0: 42.3%, +: 20.7%, ++: 37.0%), PT (0: 38.6%, +: 36.2%, ++: 25.3%). By Roussouly classification, 4.2% were Type 1, 19.3% were Type 2, 43.1% were Type 3, and 33.3% were Type 4. Moving cranially up the spine, Group P (10.6%), Group LP (54.7%) and Group TL (8.5%) did not differ in C0-C2 angle, C0 slope, MGS or CBVA (all P>0.05). Group C (26.2%) had a significantly smaller C0-C2 angle, and more negative MGS, C0 slope, and CBVA than non-cervical groups. By Roussouly type, Type 1 trended slightly higher CBVA and MGS than types 2-4 without statistical significance (all P>0.05). No differences in CL, C0-C2, or C0S were found between Types 1-4 (all P>0.05). McGregor's slope (r=-0.131, P=0.015), CBVA (r=-0.473, P<0.001) and C0 slope (r=-0.099, P=0.042) correlated most strongly with SVA compared to other Schwab modifiers. We found SVA>34mm predicted a 1 unit(degree) decrease in MGS (OR: 0.970 [0.948 - 0.993], p=0.010), while cSVA>51mm predicted a 1 unit increase in MGS (OR: 1.25[1.12-1.38], p<0.001). Group P had the lowest BL disability compared to other Groups, while Roussouly Type 1 correlated with higher BL disability compared to Type 2 (46.1 vs 37.4, P=0.007).
CONCLUSION(S): Our present study suggests that upper cervical alignment remains relatively stable through most broad variations of adult thoracolumbar deformity. Changes in SVA correlated most with upper cervical changes compared to other TL modifiers. Incremental trends in upper cervical alignment changes were observed as TL deformity extended cranially, with greatest variation in pts who also had subaxial malalignment. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
Copyright

BACKGROUND CONTEXT: Osteoporosis (OP) is a common condition affecting nearly 200 million individuals globally. Similarly, adult spinal deformity has a peak prevalence of 65% of the adult population. While bone health is instrumental in orthopaedic surgery, few studies have described the long-term outcomes of osteoporosis following surgery for ASD. PURPOSE: We sought to evaluate the impact of OP on two-year postoperative complication rates when compared to patients without OP. STUDY DESIGN/SETTING: Retrospective cohort study. PATIENT SAMPLE: Utilizing the New York State Statewide Planning and Research Cooperative System (SPARCS), we identified all patients who underwent >=4-level fusion with ICD-9 codes diagnostic for ASD (progressive idiopathic scoliosis and degenerative lumbar disease) from 2009-2011 with >=2-year follow-up. Patients with osteoporosis (OP) and without OR were identified following exclusions. OUTCOME MEASURES: Patient demographics, hospital-related parameters, postoperative complications and reoperations.
METHOD(S): Using SPARCS, we identified all patients who underwent >=4-level fusion with ICD-9 codes diagnostic for ASD (progressive idiopathic scoliosis and degenerative lumbar disease) from 2009-2011 for >=2-year minimum follow-up. Patients with osteoporosis (OP) and without OP were identified. Any patients with bone mineralization disorders (osteomalacia, rickets, hyperparathyroidism [primary, secondary, tertiary], vitamin D deficiency) and other systemic (fibrous dysplasia, sickle cell disease, renal osteodystrophy) and endocrine disorders (thyroid hypo- or hyperfunctioning disorders, adrenal insufficiency, adrenal hyperplastic syndromes) affecting bone quality or production were excluded, as were patients with surgical indications of trauma, systemic disease, infection, or cancer. The two cohorts were compared for demographics, hospital-related parameters, and 2-year postoperative complications and reoperations. Multivariate binary stepwise logistic regressions was utilized to identify significant predictors of these outcomes (covariates: OP, age, sex, race, and Charlson/Deyo).
RESULT(S): A total of 6,132 patients were identified (OP, n=490 (7.99%); No-OP, n=5,642). OP patients were older (67.6 vs 56.7 years), more often female (83.7% vs 46.2%) and white (84.3% vs 79.1%), and had higher comorbidity scores (Charlson/Deyo: 0.72 vs 0.61), all p<0.05. Patients with OP incurred higher hospital charges ($122,801 vs $108,649) and length of stay (6.7 days vs 5.8 days), both p<0.001. OP patients had higher rates of postop wound complications (13.5% vs 10.6%), acute renal failure (12.2% vs 7.90%), pseudarthrosis (3.7% vs 1.4%), blood transfusions (54.3% vs 34.6%), pneumonia (10.4% vs 6.1%), and implant-related complications (22.4% vs 14.5%); all p<=0.047. Patients in OP and no-OP cohorts experienced similar rates of postop PE, DVT, acute myocardial infarction, pneumonia, UTIs, dural tears, and CNS complications. Regression revealed that while controlling for demographics and comorbidities, OP is independently associated with increased odds of 2-year medical complications (OR=1.46), surgical complications (OR=1.55), and reoperations (OR=1.46); all p<=0.024.
CONCLUSION(S): Osteoporosis was associated with two-year postoperative complications in ASD patients. Aside from being an etiology of ASD due to vertebral fracture, osteoporosis should be considered as a comorbidity that needs to be optimized and managed perioperatively. Furthermore, this data is a call to every spine surgeon to consider metabolic bone disorders screening prior to any spinal deformity surgery. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
Copyright

BACKGROUND CONTEXT: Risk factors have been identified for complications following adult spinal deformity (ASD) surgery; however, the risk of complications following ASD surgery in relation to the degree of surgical invasiveness is unknown. Understanding the relationship between surgical invasiveness and risk of major complications is important to patients and surgeons for estimating these risks based upon the planned surgical treatment. PURPOSE: To define a surgical invasiveness threshold that predicts increased likelihood of major complications following surgical treatment of ASD. STUDY DESIGN/SETTING: Retrospective review of a prospective multicenter database PATIENT SAMPLE: Five hundred seventy-four of 760 (76%) eligible ASD patients (>5 levels fused) were identified in a multicenter database with complete 2-year follow-up OUTCOME MEASURES: Our primary outcome was development of a major complication at any time point in the postoperative period METHODS: Surgical invasiveness was calculated according to the previously published and validated ASD Surgical and Radiographic (ASD-SR) score, which assigns point values to 13 operative and radiographic factors. Youden's index was used to identify the highest predicted probability cut-off of developing a major complication to be an ASD-SR of 90. Using this value, patients were divided into quartiles (Q1: ASD-SR 0-65; Q2: ASD-SR 66-89; Q3: ASD-SR 90-119; Q4: ASD-SR 120+). Odds of developing a major complication were analyzed after controlling for baseline frailty and radiographic deformity.
RESULT(S): Mean age of patients was 59 +/- 14 years, 79% females. Mean levels fused were 11.2 +/- 4.3. The overall risk of a major complication was 17% in Q1, 21% in Q2, 35% in Q3 and 33% in Q4 (p<0.001). Comparing the odds of a major complication by adjacent quartiles demonstrated a significant increase between Q2 and Q3 (OR 1.8, 95% CI 1.03, 2.98), while the risk of increasing invasiveness from Q1 to Q2, and Q3 to Q4 were not significant (p<0.05). Similarly, patients above an ASD-SR cutoff point of 90 (Q3/Q4) were 1.9 times more likely to have a major complication than patients with a surgical invasiveness below this threshold (Q1/Q2) (OR 1.9, 95% CI 1.3 - 2.9). There were no significant differences in the odds of having a minor complication or inpatient medical complication between invasiveness groups (all p>0.05). The mean ASD-SR scores above and below the ASD-SR threshold of 90 were 120.7 +/- 25.4 and 63.4 +/- 16.8, respectively. Example of a patient with an ASD-SR of 63 (low invasiveness): T11-Pelvis, 6 Smith-Peterson Osteotomies, -.9cm change in SVA, +1degree change in TK, + 43degree change in PT. Example of a patient with an ASD-SR of 121 (high invasiveness): T8-Pelvis, 3-column osteotomy, -2.3cm change in SVA, -5degree change in TK, +38degree change in PT.
CONCLUSION(S): ASD patients have an increased risk of major complications above an ASD-SR score of 90, while the risk of minor complications and inpatient medical complications is not significantly increased. The ASD-SR score can be used as a tool to counsel patients regarding these increased risks. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
Copyright

BACKGROUND CONTEXT: The impact of worsening activities of daily living (ADL) such as spine-related financial difficulty and attending work/school have not been studied as potential independent predictors of failing nonoperative management of adult spinal deformity (ASD). PURPOSE: To identify which specific ADLs assessed with the Scoliosis Research Society 22r (SRS-22r) can identify patients with ASD who are likely to fail nonoperative management. STUDY DESIGN/SETTING: Prospective, observational study. PATIENT SAMPLE: A total of 482 patients initially selected for nonoperative treatment of ASD patients were identified from a multicenter database. Of these, 55 (11%) had eventual crossover to operative intervention. Propensity score matching (PSM) was performed using age, gender and baseline Oswestry Disability Index (ODI) to create matched cohorts of 46 crossover (CX) and 46 noncrossover (NC) patients. OUTCOME MEASURES: Our primary outcome was crossover to operative treatment among patients who were originally intended to be treated nonoperatively.
METHOD(S): Scoliosis Research Society (SRS-22r) questionnaire was administered at baseline, 6-weeks, 6-months and both 1 and 2 years. Change in overall score, subdomains and responses to specific questions over time were classified as increasing, decreasing or unchanged in relation to baseline. Kaplan-Meier curves were produced for time to crossover among patients by change in SRS-22r domains, and compared using log-rank test. Significant was set at 0.05.
RESULT(S): NC and CX groups were similar among age, baseline ODI, and SVA (p>0.05). Patients had a mean age 55 +/- 15 years; ODI of 35 +/- 15; SVA of 3.5 +/- 5.9cm. Mean time to crossover was 1.7 +/- 1.4yrs. Decline in SRS-22r Total and Activity domains were associated with increased risk of failing nonoperative management (p=0.005, p=0.006), while decline in SRS-22r pain, appearance and mental health domains were not significantly associated with failure. Analysis of specific ADLs within the activity domain showed worsening financial hardship, level of activity and going out with friends/family to be associated with failure, while work/school activity and doing household chores were not.
CONCLUSION(S): Decline in SRS-22r Activity is the primary SRS-22r domain independently associated with failing nonoperative management of ASD. Within this domain, worsening physical activity, spine-related financial hardship and decreasing time with family/friends drive patients to undergo surgery, while the ability to perform household chores and attend work/school are not independently associated with failing nonoperative management. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
Copyright

BACKGROUND CONTEXT: As surgery is increasingly recommended for patients with neurologic deterioration secondary to central cord syndrome (CCS), it is important to investigate the relationship between time to surgery and patient outcomes. The merits of early vs delayed surgical treatment remain controversial in the literature. PURPOSE: Investigate associations between time to surgical intervention and surgical outcomes for CCS patients STUDY DESIGN/SETTING: Retrospective review of Healthcare Cost and Utilization Project's Nationwide Inpatient Sample (NIS) PATIENT SAMPLE: A total of 9,246 weighted inpatient discharges. OUTCOME MEASURES: Complication rates, discharge destination, length of hospital stay (LOS).
METHOD(S): CCS patients (ICD-9 codes 952.03, 952.08, 952.13, 952.18) were isolated in the NIS database 2005-2013. Operative patients were grouped by time to intervention: same day as admission, 1-day delay, 2-day, 3-day, 4-7 days, 8-14 days, and >14 days. As appropriate, analysis of variance and chi-squared tests compared demographics, Charlson Comorbidity Index (CCI) scores, surgical details, LOS, discharge status, periop complications and total charges across patient groups. Controlling for age, CCI and concurrent traumatic fractures, binary logistic regression assessed surgical timing associated with increased odds of perioperative complication, using same-day patients as a reference group (odds ratio [95% confidence interval]).
RESULT(S): Included: 6,734 CSS patients (59+/-16yrs, 26%F, mean CCI: 1.2+/-1.6). Overall rate of surgical treatment was 64.1%, with rates of surgery increasing from 2005 (50.0%) to 2013 (73.0%, p<0.001). The most common mechanisms of injury were falls (30.3%), pedestrian accidents (6.9%), assault (3.2%) and bicycle-related injury (2.7%). Of the patients that underwent surgery, 52.0% underwent fusion (62.4% 2-3 levels, 33.2% eight-levels, 0.5% 9+ levels), 30.1% discectomy, and 13.8% other exploration/decompression of the spinal canal. Breakdown by time to procedure was: 38.5% same day, 16.1% 1 day, 9.6% 2 days, 7.5% 3 days, 16.2% 4-7 days, 8.3% 8-14 days, and 2.7% >14 days. Timing groups did not differ in trauma status at admission (shock or hemorrhage, p=0.261); however, age differed between groups (min: 1 day [58+/-15 years], max: >14 days [63+/-13 years], p<0.001). Relative to other groups, same-day patients had the lowest LOS (7.7+/-9.8 days vs 9.4-37.3 days, p<0.001) highest rates of home discharge (42.09% vs 30.9%-14.4%, p<0.001). Same-day patients showed a trend of lower perioperative neurologic complications (0.4%) than 1-day (0.6%) and 2-day (1.0%) patients, while patients delayed 3+ days had the lowest (0.1%, p=0.144). Patients delayed >14 days to surgery had increased odds of periop cardiac (7.0 [1.6-30.0]) and infection (6.1 [2.2-16.3]) complications. All timing groups beyond 3 days showed increased odds of VTE: 4-7 days (3.0 [1.6-5.5]), 8-14 days (3.0 [1.4-6.3]), 14+ days (5.6 [2.3-13.6]). Same-day surgery was also associated with lower total hospital charges than delayed surgery ($87,741 vs $118,815-$272,901, p<0.001).
CONCLUSION(S): Patients undergoing surgery for CCS on the same day as admission showed significantly lower odds of complication, hospital charges, and higher rates of discharge to home than patients that experienced a delay to operation. In contrast, patients delayed >14 days to surgery were associated with inferior outcomes, including increased odds of cardiac complication and infection. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
Copyright

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: 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