Faculty Bibliography

BACKGROUND CONTEXT: Distal junctional kyphosis (DJK) is a relatively new surgical concept often defined in the literature as a change in DJK angle <-10. This cut-off (based on previously established cut-offs for PJK) may carry clinical significance for patient quality of life; however, findings are lacking in the literature. When associated with neurological sequelae or reoperation, DJK may play a more robust role in patient HRQLs. PURPOSE: To establish a clinically relevant definition of symptomatic DJK. STUDY DESIGN/SETTING: Retrospective review of a prospective CD surgery database. PATIENT SAMPLE: One hundred and two patients with cervical deformity. OUTCOME MEASURES: Demographics, HRQL metrics.
METHOD(S): A prospective database of operative CD patients was analyzed. Inclusion criteria were cervical kyphosis >10, cervical scoliosis >10, cSVA >4cm or CBVA >25. DJK angle (DJKA) was defined >10degree change in kyphosis between LIV and LIV-2 in addition to >10degree index angle. Pts with DJKA >10degree & 1) no reop due to DJK(DJF) & 2) no physician-reported neurological sequelae at any time-point up to 1yr were categorized as "mild DJK." Those with a DJKA >10degree in addition to 1) reop due to DJK(DJF) or 2) >1 new-onset neurological sequelae related to DJK (spinal cord deficit, gait disturbance, hyperreflexia, lower-limb spasticity) were categorized as "Symptomatic DJK." ANOVA explored differences in PROMs (NDI, mJOA, EQ5D, EQ5DVAS, NRS) at baseline (BL) up to 1yr follow-up. Multivariate logistic regression analyzed predictors of inferior HRQLs associated with DJK groups, specifically scoring beyond one standard deviation (SD) of the mean value of all DJK pts.
RESULT(S): One hundred and two CD patients were analyzed. Sixty-five pts had no DJK, 25 pts had mild DJK and 12 pts had symptomatic DJK. By 1 year, 6/12 pts had DJF, 6/12 pts had >1 DJK-related neurologic sequelae not present before surgery(20% corticospinal tract deficit, 20% spasticity, 20% gait impairment, 20% hyperreflexia) without DJF, and 2 pts had both. Symptomatic DJK pts had higher mean DJKA than mild DJK pts immediately postop (29.8degree vs 19.1degree, p=0.150). No differences in BL HRQLs were noted between groups, including NDI, mJOA, EQ5D, VAS, and NRS Back (all p>0.05). At 1yr, Symptomatic DJK pts had significantly higher disability (52.3 vs 28.7, p=0.006) and trended lower EQ5D scores (0.75 vs 0.81, p=0.059), higher NRS back pain (5.82 vs 4.06, p=0.119), lower VAS (56.4 vs71.7,p=0.084), and lower mJOA (14.2 vs 15.0,p=0.495) than their mild DJK counterparts. Controlling for age and gender, conditional forward regression analysis revealed symptomatic DJK to a strong predictor of NDI >1 SD of the mean compared to mild DJK pts (OR: 43.4 [2.8 - 668.1], p=0.007); that is, symptoDJK increased the odds of NDI>1SD by at least 2.8x in relation to the mild DJK cohort.
CONCLUSION(S): DJK associated with reoperation and/or neurologic sequelae was associated with inferior quality of life metrics over long-term follow-up. Our results demonstrate that Symptomatic DJK may not necessarily correlate to a greater measured DJK angle per se (ie, >20degree); instead, DJK with concurrent neuro findings or subsequent reop better predicts worsened disability compared to DJK alone. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: The operative treatment of adult spinal deformity (ASD) can be very technically challenging with high complication rates. Despite these challenges it is well established that patients ultimately benefit from such treatment. However the surgical outcomes for patients with severe sagittal deformity have not been reported. PURPOSE: To investigate whether patients with severe sagittal deformity have favorable outcomes following surgical correction. STUDY DESIGN/SETTING: Retrospective review of a prospective, multicenter adult spinal deformity (ASD) database. PATIENT SAMPLE: Inclusion criteria: operative patients with age >=18, SVA >=15cm, PI-LL >=30degree, and/or lumbar kyphosis >=5degree with minimum 2-yr follow-up. OUTCOME MEASURES: Health-related quality of life (HRQOL) scores included: Oswestry Disability Index (ODI), Short Form-36 (SF36), Scoliosis Research Society (SRS22), back/leg pain numerical rating scale (NRS) and minimum clinically important difference (MCID)/substantial clinical benefit (SCB) for pts eligible to meet them. Radiographic values included: max coronal cobb angle, coronal C7 plumb line, pelvic tilt (PT), mismatch between pelvic incidence and lumbar lordosis (PI-LL), thoracic kyphosis (TK), C7 sagittal vertical axis (SVA). Demographic, frailty, surgical, and complications data were also collected.
METHOD(S): Comparisons between 2-yr postop and baseline HRQOL/radiographic data were made. P<0.05 was considered significant.
RESULT(S): A total of 138 pts were included (54.3% Female, ave age 63.3+/-11.5yrs). Ave baseline frailty score was 4.1+/-1.4 indicating the pt to befrail. Ave OR time 386.2+/-136.5min, EBL 1829.8+/-1474.6cc. 71 (51.4%) of the pts had a prior fusion; 89.9% posterior fusion only, 9.4% combined anterior-posterior approach. Mean number posterior levels fused 11.5+/-4.1. 44.9% had a 3-column osteotomy and 68.8% had interbody fusion. All 2-yr postop radiographic parameters were significantly improved compared to baseline (p<0.05 for all) except coronal C7 plumb line (p>0.05). All 2-yr HRQOL measures were significantly improved compared to baseline (p<0.004 for all); 46.6-73.8% of pts met either MCID or SCB for all HRQOL; 74.6% of pts had at least 1 complication, 11.6% had 4 or more complications, 33.3% had at least 1 major complication, and 42 (30.4%) had a postop revision.
CONCLUSION(S): Pts with severe sagittal malalignment benefit from surgical correction at 2-yrs postop both radiographically and clinically despite having a high complication rate. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Analysis of interactions spinal alignment metrics may uncover novel and powerful alignment parameters, similar to pelvic incidence minus lumbar lordosis (PI-LL). PURPOSE: This study utilized a data driven approach to hypothesis generation by testing all possible division interactions between a set of spinal alignment parameters. TPA divided by PI (TPA/PI) was identified and subsequently characterized. STUDY DESIGN/SETTING: Retrospective analysis of a multicenter, prospectively-defined, consecutive cohort of ASD patients. PATIENT SAMPLE: A total of 1,439 patients with baseline ODI were included for hypothesis generation; 666 patients had 2-year postoperative follow-up and were included for validation. OUTCOME MEASURES: The primary outcome measure was Oswestry Disability Index (ODI).
METHOD(S): All possible combinations of division interactions between baseline metrics were assessed with linear regression against baseline ODI. Further analyses also utilized linear regression.
RESULT(S): From 247 raw alignment metrics, 32,398 division interactions were considered in hypothesis generation. Low-cervical and high-thoracic pelvic angles divided by pelvic incidence accounted for 7 of the top 10 most significant interactions. Conceptually, the TPA/PI is a measure of the relative alignment of the line connecting T1 to the femoral head and the line perpendicular to the sacral end plate. Among the validation cohort, the mean TPA/PI was 0.41 (SD 0.24) at baseline and 0.30 at 2 years postoperatively (SD 0.18). Higher TPA/PI was linearly associated with worse ODI at baseline (beta 28.7 for TPA/PI 1 vs 0, p<0.0001), 1 year (beta 16.5, p<0.0001), and 2 years (beta 20.0, p<0.0001). Further, the change in ODI at 2 years from baseline was linearly associated with the change in TPA/PI (beta 9.5, p=0.0172). The optimal statistical cutpoints for TPA/PI discriminating patients based on ODI were 0.21 and 0.41, labeled as 0 (<0.21), + (0.21-0.41), and ++ (>=0.41). At baseline, patients in the 0 group exhibited lower ODI as compared to patients in the + (41.8 vs 32.0, p<0.0001) and ++ (50.7 vs 32.0, p<0.0001) groups. The R-squared for regression of ODI against categorical TPA/PI alone (0.154) was directionally higher than that for the Schwab modifiers (SVA: 0.138, PI-LL 0.111, PT 0.057).
CONCLUSION(S): This study utilized a data-driven approach for hypothesis generation and identified TPA/PI, the spinopelvic ratio (SPR), as a promising measure of sagittal spinal alignment among ASD patients. This value is strongly associated with the Schwab modifier classification system. Patients with SPR >=0.21 exhibited inferior HRQOL. The SPR classification accounted for a directionally greater proportion of variance in ODI as compared to the three Schwab modifiers. These results highlight the interaction between global sagittal alignment and adequate pelvic structural support. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Several methodologies have been proposed to determine ideal adult spinal deformity (ASD) sagittal spinopelvic alignment, two of them being; (1) patient age adjusted alignment based on pelvic incidence-lumbar lordosis (PI-LL), and sagittal vertical alignment (SVA) and (2) global alignment and proportion (GAP) score (a calculator initially developed to assess proximal junctional kyhosis [PJK] risk). A recent study evaluating the ability of different methodologies to predict PJK highlighted GAP inability to effectively predict PJK outside the original GAP creation data set. PURPOSE: Investigate a novel methodology (comprehensive alignment planing, or CAP) that utilizes a hybrid approach to assess ASD alignment by combining age adjusted alignment thresholds with concurrent alignment parameters. STUDY DESIGN/SETTING: Retrospective review of a prospective ASD database. PATIENT SAMPLE: Surgically treated ASD patients minimum 2-year follow-up. OUTCOME MEASURES: Sagittal alignment, ODI, SF-36, SRS-22r, proximal junctional kyphosis/failure, CAP and GAP scores.
METHOD(S): Multicenter ASD database was evaluated for surgically treated ASD patients with (1) fusion with a minimum of 5 levels, (2) fusion to pelvis, and (3) minimum 2-year follow-up. The CAP scoring methodology was created by assigning numerical values to the difference between each patient's postoperative sagittal alignment and ideal alignment as defined by previously reported age generational norms for PI-LL, PT, and TPA. CAP score ranges from -3 (if a patient is under corrected for all 3 parameters by at least 10 years) to +9 (if a patient is overcorrected by at least 30 years in all 3 parameters). A cumulative CAP score -1 to +2 represents unity between patient postop alignment and age alignment targets, CAP<=-2 represents under-correction, and CAP>+2 represents overcorrection. Postoperatively, PJK severity was categorized as None, PJK (angle 10degree), Severe-PJK (28degree), and PJF (PJK treated surgically). Postop HRQOL and PJK severity between each GAP and CAP categories were evaluated.
RESULT(S): Four hundred and nine667 patients meeting inclusion criteria were evaluated. Preoperatively most of the patients had moderate to severe deformity per SRS-Schwab modifiers (PT: 26degree, PI-LL=20degree, and SVA=80 mm). At 2 years, mean CAP score increased from -0.8+/-2.4 to +0.8+/-2.9 (p<0.001); 24.5% of the patients were undercorrected, 38.3% overcorrected, and 37.5% matched their age-adjusted target. By comparison GAP analysis categorized 29.6% of the patients as proportional, 39.9% as moderate deformity, and 36.5% as severe deformity. Postoperatively, HRQOL differences between CAP groups included ODI (p=0.025), SF36 MCS (p=0.014), SRS Pain (p=0.029) and SRS Total (p=0.043), while GAP was unable to discern HROQOL differences between GAP categories. PJK occurred in 37.9% of patients, severe PJK in 9.8%, and PJF in 6.6%. CAP score increased as PJK worsened (CAP=0.63 for no PJK, 1.42 for PJK, 2.31 for severe PJK, and 3.5 for PJF, p<0.001), however GAP score was unable to identify severity of PJK.
CONCLUSION(S): Evaluation of a novel ASD alignment assessment tool (CAP) demonstrates improved ability to predict the occurrence and severity of PJK compared to previously reported tools. Additionally the CAP tool correlates well with postoperative patient outcomes including HRQOL. The CAP tool may aid ASD surgical planning via use of age-adjusted alignment parameters allowing surgeons to target a postoperative alignment that minimizes complications and optimize surgical outcomes. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Patients with severe cervical deformity (CD) often have profound deficits in numerous activities of daily living. Association between health status and postoperative radiographic goals is difficult to quantify. PURPOSE: Investigate the radiographic characteristics of patients who achieved optimal HRQOLs following surgery for CD. STUDY DESIGN/SETTING: Retrospective review of prospective CD database. PATIENT SAMPLE: Forty adult CD patients (C2-C7 Cobb>10degree, CL>10degree, cSVA>4cm, or CBVA>25degree). OUTCOME MEASURES: Health-related-quality of life (HRQL) scores, radiographic alignment.
METHOD(S): Surgical patients with severe CD were isolated based upon a previously presented combination of preop cSVA, T1 slope, maximum focal kyphosis in extension, C2 slope in extension, and number of kyphotic levels in extension. Those with available preop and 1-year postop HRQL data were included. Based on previous study, patients were grouped into 3 distinct patterns of CD: focal deformity (FD), flatneck (FN=large TS-CL and lack of compensation), or cervicothoracic (CT). Postoperative outcomes were defined as "good" if a patient had >2 of the 3 following criteria (1) NDI <20 or meeting MCID, (2) mild myelopathy (mJOA>=13), and (3) NRS-Neck <=5 or improved by >2 points from baseline. Within each distinct deformity group, patients with good outcomes were compared to those with poor outcomes (ie, not meeting the criteria for good) for differences in demographics, HRQL scores, and alignment, via chi-squared or student's t-tests.
RESULT(S): Overall, 83/153 patients met the criteria of severe CD and 40 patients had complete 1-year follow-up of clinical/radiographic data. Patient breakdown by deformity pattern was as follows: CT (N=13), FN (N=17), and FD (N=17), with 7 patients meeting criteria for both FD and FN deformities. Within the FD cohort, maximal focal kyphosis (ie, kyphosis at one level) was better corrected in patients with a "good" outcome (p = 0.03). In the FN cohort, patients who went on to have "good" outcomes presented with worse horizontal gaze (McGregor slope 21degree vs 6degree, p=0.061) and cSVA (72 mm vs 60 mm, p=0.030). "Good" outcome FN patients showed significantly greater postop correction of horizontal gaze (-25degree vs -5degree, p = 0.031). In the CT cohort, patients with "good" outcomes had superior global alignment both pre- (SVA: -17 mm vs 108 mm, p <0.001) and postoperatively (50 mm vs 145 mm, p=0.001). CT patients with "good" outcomes also had better postop cervical alignment (cSVA 35 mm vs 49 mm, p=0.030), and less kyphotic segments during extension (p=0.011). In the FD cohort, there were no differences between "good" and "poor" outcomes patients in preoperative alignment; however, "good" outcome patients showed superior changes in postoperative focal kyphosis (-2degree vs 5degree, p=0.030). Within all three deformity pattern categories, there were no differences between "good" and "poor" outcome patients with respect to demographics or surgical parameters (levels fused, surgical approach, decompression, osteotomy, all p>0.050).
CONCLUSION(S): The results of this study highlight intraoperative goals for three distinct sagittal morphotypes of severe CD: cervicothoracic, flat neck, and focal deformity. Distinct deformity specific intraoperative goals include obtaining proper sagittal global/cervical alignment for cervicothoracic patients, correcting maximal focal kyphosis in focal deformity patients, and correcting horizontal gaze for flat neck patients. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Persistent lumbopelvic malalignment following ASD-corrective surgery may impair quality of life and result in persistent pathologic compensation in the lower extremities. Patient-specific age- and BMI-adjusted alignment targets have been proposed to improve alignment outcomes; however, it is unclear whether reaching these postop targets reduces rates of pelvic nonresponse following surgery. PURPOSE: Assess the relationship between pelvic nonresponse to ASD-corrective surgery and persistent lower-extremity compensation. STUDY DESIGN/SETTING: Single center retrospective review. PATIENT SAMPLE: Fifty-eight ASD patients. OUTCOME MEASURES: Sagittal alignment.
METHOD(S): Included: surgical ASD patients with full-spine X-ray imaging at pre- and early postop follow-up (<1Y). Patients were grouped by postop improvement in PT, per SRS-Schwab Classification: those who did not improve (pelvic nonresponders, PNR), and those that did improve (pelvic responders, PR). Groups were propensity score matched for preop PT, and assessed for differences in demographics, surgical factors, and alignment (sagittal spinal and lower extremity) with means comparison tests. Rates of persistent postop lower extremity compensation (defined as no improvement in lower extremity alignment) were compared between groups. Subanalysis assessed the relationship between reaching postop age- and BMI-specific alignment targets and rates of pelvic nonresponse.
RESULT(S): Following propensity score matching, PNR (N=29) and PR (N=29) patients did not differ in age, sex, BMI or preop sagittal spinal alignment (all p>0.05); however, PNR patients presented with less knee flexion (9degree vs 14degree, p=0.043). Groups did not differ in levels fused (10.8 vs 10.8, p=0.974) or osteotomy (93% vs 92%, p=0.902). Postop, PNR patients had inferior lumbopelvic alignment in PT (30degree vs 17degree), PI-LL (17degree vs 3degree), and greater global malalignment for TPA (27degree vs 15degree, all p<0.001). For PNR patients, these changes in alignment were accompanied by greater compensatory anterior hip extension (53mm vs 31mm, p=0.021). PNR patients also showed greater pre- to postop increases in sacrofemoral angle (2degree vs -5degree), and smaller decreases in hip extension (-24mm vs -64mm), pelvic femoral angle (-1.4degree vs -3.8degree), and global sagittal angle (-3.5degree vs -8degree, all p<0.005), indicating persistent lower extremity compensation. PNR patients had higher rates of persistent postop lower extremity compensation for sacrofemoral angle (68% vs 25%), ankle flexion (64% vs 33%), and pelvic shift (28% vs 4%, all p<0.034). PNR and PR groups did not differ in rates of reaching age- and BMI specific ideal postop alignment for PT, SVA, TPA, or PI-LL (all p>0.05). For patients with severe preop SVA deformity, overcorrection relative to ideal postop PT targets was associated with lower rates of pelvic non-response (under: 12%, match: 18%, over: 71%, p<0.001). Lower rates of nonresponse were observed for patients with severe preop PT deformity overcorrected relative to ideal postop PI-LL (under: 0%, match: 30%, over: 70%, p=0.016).
CONCLUSION(S): Pelvic nonresponders following ASD-corrective surgery had higher rates of persistent compensatory action in the lower extremities. Patients with severe preop PT deformity who were surgically overcorrected with respect to ideal PI-LL had lower rates of postop pelvic nonresponse, indicating that for severely malalignmed patients, existing alignment targets may need to be adjusted to optimize alignment outcomes. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Adult spinal deformity (ASD) surgery often involves complex deformity correction. It's unknown which baseline (BL) patient factors predict lower total costs in ASD surgery. PURPOSE: Identify predictors of lower total surgery costs for ASD patients. STUDY DESIGN/SETTING: Retrospective review of a prospective multicenter adult spinal deformity database. PATIENT SAMPLE: A total of 311 operative ASD patients >=18 years old with baseline and 3Y demographic, surgical, and frailty data. OUTCOME MEASURES: Schwab sagittal vertebral axis (SVA) modifier grade, Owestry Disability Index (ODI), costs of ASD surgery, predictors of lower costs.
METHOD(S): Inclusion criteria included surgical ASD (scoliosis >=20degree, SVA >=5cm, PT >=25degree, or thoracic kyphosis >=60degree) patients >18 years with available frailty, demographic, and radiographic data at BL and 1 year postop. Descriptive analyses assessed mean age, frailty, and surgical data. Total costs for surgery were calculated using the PearlDiver database. A conditional variable importance table used nonreplacement sampling set of 20,000 conditional inference trees to identify the top factors associated with lower cost surgery for low (LSVA), moderate (MSVA), and high (HSVA) Schwab modifier grades. LSVA were SVA<4 cm, MSVA 4 cm-9.5 cm, HSVA were >9.5 cm. Linear and logistic regression assessed the relationship between significant predictors and the odds of lower cost surgery.
RESULT(S): Of the 322 total ASD patients, 322 met inclusion criteria. Descriptive statistics were: age 58.9 +/- 14.9, 76% women, BMI 27.8 +/- 6.2, 62% osteotomy, 54% decompression, and 11.0 +/- 4.1 average levels fused. At 3yrfollow-up, the potential cost of ASD surgery ranged from $57,606.88 to $116,312.54. There were 152 LSVA patients, 53 MSVA patients, and 111 HSVA patients. For all patients, BL ODI < 50 (2.22 [1.53-3.23], p<0.001), BL SRS Activity >1.5 (2.62 [1.402-4.875], p=0.002], no previous spine surgery (1.77 [1.22-2.58], p=0.003), frailty scores <0.19 (2.92 [1.69-5.08], p<0.001), no SVA modifiers (1.59 [1.09-2.33], p=0.017), no PI-LL modifiers (1.62 [1.10-2.40] p=0.015), invasiveness scores below 80.8 (1.51 [1.02-2.24] p=0.04), and no depression (1.55 [1.03-2.31] p=0.03) were predictive of lower costs. For LSVA patients specifically, no osteoporosis (7.87 [2.47-25.09] p=<0.001), SRS activity >1.5 (6.76 [1.68-27.18] p=0.007), age <64 (4.37 [1.74-10.99] p=0.002), BL ODI <50 (2.83 [1.14-7.04] p=0.025), SRS total scores >2.38 (3.93 [1.54-10.18] p=0.004), frailty scores <0.37 (2.74 [1.07-6.99] p=0.035), and increasing invasiveness (1.01 [1.00-1.03] p=0.041) were predictive of lower costs. For MSVA patients, invasiveness <94.16 (9.82 [1.00-104.17] p=0.058), no cancer (16.00 [0.80-42.5] p=0.071), and frailty scores <0.3 (3.8 [0.48-30.42] p=0.21) trended towards lower costs. For HSVA, no history of smoking (4.50 [0.90-22.47] p=0.06) and BMI <27.8 (2.84 [0.94-8.60] p=0.06) trended towards lower costs.
CONCLUSION(S): For ASD patients, low frailty, no prior spine surgery, no depression, and higher baseline SRS activity scores were predictive of lower total surgery costs. When assessed by baseline deformity, decreased frailty and the lack of comorbidities and risk factors such as cancer, smoking, or high BMI, were associated with lower costs. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: The efficacy of surgical intervention for central cord syndrome (CCS) is shown in the literature; however, it is unclear whether disparities in patient presentation and treatment exist between those who initially undergo operative treatment and those who delay operative treatment. PURPOSE: In a population of CCS patients, assess disparities in presentation and treatment between those undergoing immediate surgery and those who delay operative treatment. STUDY DESIGN/SETTING: Retrospective analysis of New York State Inpatient Database years 2004-2013. PATIENT SAMPLE: A total of 1,301 CCS patients (ICD-9 codes 952.03, 952.08, 952.13, 952.18). OUTCOME MEASURES: Time to surgery, length of stay (LOS).
METHOD(S): Patient-specific linkage codes allowed longitudinal tracking of inpatient stays within the study period. Demographics, comorbidities (Charlson Comorbidity Index [CCI]), complications, and surgical factors, including Mirza invasiveness score, were compared between CCS patients that initially underwent surgery (Initial) and patients that delayed operative treatment (Delayed) using Chi-squared tests and independent samples t-tests as appropriate. Similar tests assessed differences in demographics and comorbidity burden between nonoperative patients and surgical crossover patients.
RESULT(S): Included: 1,301 CCS patients (62+/-16 yrs, 27% female). Follow-up rate was 67.3%; mean follow-up time was 515+/-707 days. By level of CCS injury, 61.0% of patients were injured between C1 and C4, 59.2% between C5-C7, 1.0% between T1-T6, and 0.6% between T7-T12. Overall, 800 (61%) patients underwent surgical treatment (procedural breakdown: 80% fusion, 59% decompression, including 38% discectomy and 23% other decompression of the spinal canal). Of the surgical patients, 621 (78%) had surgery at first recorded hospital visit, while 179 (22%) experienced a delay before surgical treatment. For patients that delayed treatment, mean time to surgery was 203+/-358 days. Initial and Delayed patients did not differ in sex (p=0.109) or CCI (p=0.894), though Initial patients were younger than Delayed (60+/-15 yrs vs 63+/-13, p=0.016) and had lower rates of diabetes and valvular disease (both p<0.04). Initial patients underwent more invasive procedures than Delayed (5.1+/-2.6 vs 4.3+/-3.2, p=0.003), including higher rates of fusion (84% vs 71%, p<0.001), but not decompression: overall (59% vs 60%, p=0.816), discectomy (39% vs 35%, p=0.306), other canal decompression (22% vs 27%, p=0.175). LOS was longer for Initial patients (16+/-20 days vs 7+/-10, p<0.001), but complication rates did not differ (all p>0.05). Patients who delayed operative treatment did not differ from nonop patients in age (63+/-13 vs 63+/-17, p=0.802) or CCI (1.04+/-1.49 vs 1.06+/-1.49, p=0.923); however, Delayed patients had higher rates of diabetes (26% vs 18%, p=0.037), neurologic disorders (7% vs 1%, p<0.001), and valvular disease (6% vs 2%, p=0.026) than patients that remained nonoperative.
CONCLUSION(S): Although patients managed with initial surgical treatment of CCS had longer hospital stays and were treated with more invasive procedures, perioperative complications did not differ. Twenty-two percent of CCS patients crossed over from nonoperative to operative treatment, with a mean time to crossover of 203 days. Patients who crossed over to operative care were more comorbid than patients who remained nonoperative, indicating comorbidity burden may play a role in the decision to operate. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Many patients are unable to undergo a major cervical deformity corrective surgery due to deformity severity, age, comorbidities, and overall frailty status. In order to optimize quality of life in patients with cervical deformity, there may be alignment targets to be prioritized. PURPOSE: To prioritize the cervical parameter targets for alignment. STUDY DESIGN/SETTING: Retrospective review of a multicenter prospective cervical deformity database. PATIENT SAMPLE: Seventy-seven patients undergoing cervical deformity (CD) corrective surgery. OUTCOME MEASURES: Cervical regional alignment parameters: cervical sagittal vertical axis(cSVA), cervical lordosis(CL), T1 Slope minus CL(TS-CL), chin brow vertical angle(CBVA), McGregor's slope(MGS), C2-T3 plumb line(C2-T3 SVA), C2-T3 angle, C2 Slope. Health-related quality of life measures: NDI.
METHOD(S): Included:CD patients (C2-C7 Cobb>10degree, CL>10degree, cSVA>4cm, or CBVA>25degree) with full baseline (BL) and 1-year (1Y) radiographic parameters and NDI scores; patients with cervical or cervicothoracic Primary Driver Ames type. Patients with BL Ames classified as low CD for both parameters of cSVA(<4cm) and TS-CL(<15degree) were excluded. Patients assessed: Meeting MCID for NDI(<-15 DELTANDI). Ratios of correction were found for regional parameters (cSVA, CL, T1 Slope, TS-CL, CBVA, MGS, C2-T3 SVA, C2-T3 angle, C2 Slope) categorized by Primary Ames Driver (cervical[C] or cervicothoracic[CT]). Decision tree analysis assessed cut-offs for differences associated with meeting NDI MCID at 1Y.
RESULT(S): Seventy-seven CD patients included (62.1yrs, 64%F, 28.8kg/m2). Average CCI: 0.94, 7% current smokers. By approach, anterior: 19.4%, posterior: 41.6%, combined approach: 39%. Mean anterior levels fused: 3.5, posterior: 8.3, total: 7.5. Average op time: 553.1min; mean EBL: 1128.1ccs. 41.6% met MCID for NDI. A backwards linear regression model including radiographic differences as predictors from BL to 1 year for meeting MCID for NDI demonstrated an R2 of 0.820 (p=0.032) included TS-CL, cSVA, MGS, C2SS, C2-T3 angle, C2-T3 SVA, CL. By primary Ames driver, 67.5% of patients were categorized as C, and 32.5% as CT. Ratios of change in predictors for MCID NDI patients (BL -1Y) for C driver patients: 260.8% MGS, 140.3% CL, 121.2% C2-T3 angle, 49.6% C2 slope, 41.1% cSVA, 20.5% TS-CL, 3.1%C2-T3 SVA. While correction in CT driver patients included: 168.7% CL, 93% MGS, 70.8% C2-T3 angle, 31.1% cSVA, 27.5% C2 slope, 24.9% TS-CL, 13.7% C2-T3 SVA. The ratios were not significant between the two groups(p>0.050). Decision tree analysis determined cut-offs for radiographic change, prioritizing in the following order (based upon ordinal regression values): a correction <=42.5degreeC2-T3 angle (OR: 5.667[1.074-29.891], p=0.041), <35.4degreeCL (OR:4.636[0.857-25.071], p=0.075), >-31.76degreeC2 slope (OR: 3.2 [0.852-12.026], p=0.085), >-11.57mm cSVA (OR: 3.185[1.137-8.917], p=0.027), >-2.16degree MGS (OR: 2.724[0.971-7.636], p=0.057).
CONCLUSION(S): Certain ratios of correction of cervical parameters contribute to improving neck disability. Specific cut-offs of radiographic differences from baseline to 1 year were found prioritizing C2-T3 angle, followed by cervical lordosis, C2 slope, C2-C7 plumb line, and McGregor's slope, all strongly associated with meeting the minimal clinically important difference for the neck disability index score. Prioritizing these radiographic alignment parameters will optimize patient-reported outcomes for patients undergoing cervical deformity surgery. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: The Adult Spinal Deformity Invasiveness Index incorporates deformity-specific components to assess the magnitude of correction. It's unknown how invasiveness relates to outcomes in each frailty state. PURPOSE: Investigate the relationship between increasing invasiveness and outcomes in adult spinal deformity (ASD) surgery in each frailty states. STUDY DESIGN/SETTING: Retrospective review of prospective, consecutively enrolled multicenter ASD database. PATIENT SAMPLE: One hundred ninety-five ASD patients with baseline demographic and surgical details. OUTCOME MEASURES: Invasiveness, frailty, minimal clinically important differences (MCID) for the Oswestry Disability Index, SF-36 Physical Component Scores, and Scoliosis Research Society Scores.
METHOD(S): ASD patients (scoliosis >=20degree, SVA >=5cm, PT >=25degree, or TK >=60degree) with baseline frailty and invasiveness scores. Invasiveness index included: posterior: decompression (1), fusion (2), instrumentation (1); osteotomies: 3-coloumn (14), Ponte (1), interbody fusion: anterior lumbar (8), transforaminal/posterior lumbar (2), iliac fixation (2), revision surgery (3). Invasiveness scores were calculated within different frailty states (not frail, NF, <0.3), frail (F, 0.3-0.5), severely frail (SF, >0.5). Logistic regression analysis assessed the relationship between increasing invasiveness and major complications or reoperations and meeting MCID for any of the measured HRQLs at 3 years. Decision tree analysis assessed thresholds for an invasiveness risk benefit cutoff point, above which experiencing complications or reoperations and not reaching MCID were higher. Significance was set to p<0.05.
RESULT(S): Of the 322 patients, 195 met inclusion criteria. Baseline demographic info: age 59.9+/-14.4, 75% female, BMI 27.8+/-6.2, CCI 1.7+/-1.7. Baseline surgical info: 61% osteotomy, 52% decompression, 11.0+/-4.1 levels fused. There were 98 NF, 65 F, and 30 SF patients. For the entire cohort, binary regression analysis found a significant relationship between increasing invasiveness and experiencing a major complication or reoperation (1.01[1.00-1.02], p=0.01). Within each frailty subgroup, the results were 1.01([1.00-1.03], p=0.05) for NF, 1.01([1.01-1.02], p<0.001) for F, and 1.01 ([1.00-1.01], p=0.02) for SF. When defining no major complications or reoperation and meeting MCID in any HRQL at 3 years as a favorable outcome, decision tree analysis established an invasiveness risk benefit cutoff of 63.9. Patients below this threshold were 1.8 [1.38-2.35] (p<0.001) times more likely to not have a major complication/reoperation and meet MCID at 3 years. Invasiveness above this point was a negative predictor (0.55[0.401-0.754], p<0.001). When factoring in frailty, for NF patients the risk benefit cutoff was 79.3 (2.11[1.39-3.20] (p<0.001), 111 for F (2.62 [1.70-4.06] (p<0.001), and 53.3 for SF (2.35[0.78-7.13] (p=0.13).
CONCLUSION(S): Increasing invasiveness is associated with increased odds of major complications and reoperations. A risk/benefit cutoff for decreasing major complications/reoperations and meeting MCID was found to be 79.3 for NF patients, 111 for F patients, and 53.3 for SF patients. Above these thresholds, increasing invasiveness is associated with increasing the risk of major complications or reoperations and not meeting MCID at 3 years. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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