Faculty Bibliography

INTRODUCTION/BACKGROUND:The sacroiliac joint (SIJ) is a potential source of pain in the ASD population. Incidence and predictors of preoperative SIJ pain and rates of resolution with surgery in the ASD population are not well understood. METHODS:A prospective, multicenter database of surgically treated ASD patients was queried for baseline SIJ pain at the preoperative assessment. SIJ pain was defined as self-reported back pain in the posterior superior iliac spine region scored ≥4 out of 10 and ≥3 of 5 positive provocative SIJ maneuvers. Demographic data, spinal alignment parameters, and health assessments were assessed using Wilcoxon and χ 2 analysis. Predictors of preoperative SIJ pain were assessed with univariate and multivariate logistic regression. RESULTS:A total of 735 patients were included with a mean (SD) age of 61.3 (15.3) years, BMI of 27.6 (5.4), Edmonton Frailty Score (EFS) of 3.4 (2.5), and Charlson Comorbidity Index (CCI) of 1.1 (1.8). A total of 65% were female and 6% were tobacco users. A total of 411 patients had self-reported PSIS pain and 53 patients (7.2%) had preoperative SIJ pain as assessed by SIJ maneuver testing. SIJ pain was not associated with history of prior lumbosacral fusion ( P =0.23). Patients with SIJ pain had higher BMI (30.0 vs . 27.4, P =0.004), preoperative pain medication usage (92.5% vs . 77.7%, P =0.02), EFS (4.6 vs . 3.3, P <0.001), and CCI (1.6 vs . 1.0, P =0.006) as well as lower L4-S1 lordosis (28.7 vs . 34.5, P =0.02) and greater L1 pelvic angle (14.5 vs . 10.8, P =0.03). After variable selection with univariate regression, multivariate logistic regression identified higher BMI (OR 1.06, P =0.033) as a significant predictor of SIJ pain at preoperative. In the patient cohort with SIJ pain at preoperative, 91.7% reported no SIJ pain at 1-year follow-up. 11/53 (20.8%) patients with baseline pain and SIJ fusion performed concurrently with ASD surgery had 100% resolution of SIJ pain in this cohort; however, there was no significant difference in pain resolution between patients with SIJ fusion and those without ( P =1). CONCLUSION/CONCLUSIONS:We found a lower prevalence of preoperative SIJ pain in ASD patients than what has been historically reported, present in 7.2% of patients. Higher BMI was a predictor of preoperative SIJ pain in this population. ASD surgery led to resolution of SIJ pain in >90% of patients at 1-year follow-up.

BACKGROUND/UNASSIGNED:The increasing prevalence of adult spinal deformity (ASD) highlights the need for effective treatment strategies. While minimally invasive spine surgery has improved outcomes, patients with severe deformity often require more extensive correction. This study evaluates the outcomes of combining prone transpsoas (PTP) lumbar interbody fusion with posterior column osteotomies (PCO) or pedicle subtraction osteotomies (PSO) for severe ASD correction. METHODS/UNASSIGNED:-tests, and Spearman's rank coefficients were used to evaluate correlations. RESULTS/UNASSIGNED:Complication rates were similar between PCO and PSO patients. Significant improvements were observed in lumbar lordosis (LL) (P=0.002), SVA (P=0.03), TPA (P=0.04), coronal Cobb angle (P=0.03), and PI-LL mismatch (P=0.003). SL did not change significantly at any level. Clinically, ODI, VAS-B, and VAS-L scores improved significantly (P<0.001 for all). Correlations showed moderate to strong negative associations between SL at L2-L3 and patient-reported outcomes. CONCLUSIONS/UNASSIGNED:Combining PTP with PCO or PSO provides significant radiographic and clinical improvements in severe ASD patients. This hybrid approach may serve as a safe, efficient alternative to traditional multistage open surgeries, warranting further prospective validation.

STUDY DESIGN/METHODS:Retrospective cohort study using a multicenter, prospectively collected adult spinal deformity (ASD) database. OBJECTIVE:To determine whether achieving the ideal L1 pelvic angle (L1PA) in minimally invasive surgery (MIS) for ASD correction is associated with reduced mechanical failure and improved clinical outcomes. SUMMARY OF BACKGROUND DATA/BACKGROUND:Prior research has shown that achieving ideal L1PA-defined as (0.5×pelvic incidence)-21-is linked to lower reoperation risk in open ASD correction. Its relevance in MIS has not been well established. METHODS:A total of 1104 ASD patients across 13 centers were included (criteria: scoliosis ≥20°, SVA ≥5 cm, PT ≥25°, or TK ≥60°, with ≥2-year follow-up). Radiographic parameters and patient-reported outcomes (PROs) were collected preoperatively, at six weeks, and at final follow-up. Ideal L1PA was defined as within ±5° of the calculated target. MIS was defined as circumferential MIS (LLIF/ALIF with percutaneous posterior fixation). Associations between alignment and outcomes (reoperation, PROs) were analyzed using linear regression and t tests. RESULTS:Ideal L1PA was achieved in 63% of MIS cases and 61% of open cases ( P =0.342). Among MIS patients, ideal L1PA correlated with lower reoperation rates (15% vs. 33%, P <0.01) and greater improvement in SRS-22 total (Δ0.85 vs. Δ0.40, P <0.01) and SF-36 PCS scores (Δ9.1 vs. Δ4.6, P =0.04). In contrast, ideal L1PA was not associated with reduced reoperation in the open group. Across all patients, each 1° deviation from ideal L1PA increased reoperation risk by 1.8% ( P =0.04). CONCLUSIONS:Ideal L1PA is achievable in MIS at similar rates as open surgery. In MIS-treated ASD patients, achieving ideal alignment is associated with reduced reoperation and improved clinical outcomes, supporting its role as a key surgical target.

STUDY DESIGN/METHODS:Multicenter prospective study. OBJECTIVE:The present study investigates in-construct measurements of sagittal angles (SA) within the fusion from C2 to various thoracic vertebrae, which can be used as targets for CD correction. SUMMARY OF BACKGROUND DATA/BACKGROUND:Correcting cervical deformity (CD) has the potential to significantly improve patient function. However, previously described radiographic parameters cannot be measured intraoperatively. METHODS:Patients with CD that had a LIV at T1 or caudal were included. Patients were categorized into the failed outcome group if they had a cSVA of more than 4 cm within 3 months postoperatively. The in-construct measurements were based on patients' LIV. All patients had a C2-T1 SA. C2-T4 SA were compared between groups with LIV below T4, and C2-T10 SA between groups with LIV below T10. Change in C2-LIV SA described the correction within the fusion for each patient. Linear regression analysis was used to determine the C2-T1, C2-T4, C2-T10 SA measures corresponding to a cSVA = 4 cm.HRQL analysis was done in patients with 1-year follow-up. RESULTS:Among 143 patients (mean age 63, 60% female), 51% had radiographic failure. Multivariate regression showed that postoperative C2-T1 SA independently predicted failed alignment (OR = 1.22, CI 1.10-1.35; P < 0.001). A cSVA of 4 cm correlated with a C2-T1 SA of -9.6° and C2-T10 SA of 14.7° (r > 0.38, P < 0.05). ΔDJKA was found to significantly correlated with the C2-T10 SA (r > 0.57, P = 0.02). Though HRQL outcomes did not differ significantly between groups, greater C2-LIV SA correction was associated with improved neck pain (r > 0.42, P = 0.036). CONCLUSION/CONCLUSIONS:Failure to restore cSVA and development of DJK was independently associated with under correction as evidenced by significantly larger postoperative in-construct angles.

STUDY DESIGN/METHODS:Retrospective review of a prospective, multicenter adult cervical deformity (CD) database. OBJECTIVE:Investigate the prevalence and clinical significance of combined cervical scoliosis (CS) and cervical kyphosis (CK) among patients undergoing surgical management of CD. SUMMARY OF BACKGROUND DATA/BACKGROUND:Although adult CD patients may have both CS and CK, few studies have confirmed prevalence of CK and CS and associated radiographic and clinical findings. MATERIALS AND METHODS/METHODS:Patients undergoing surgery for CD [defined as C2-C7 ≥10° kyphosis, cervical sagittal vertical axis (SVA) >4 cm, or C2-C7 coronal Cobb angle ≥10°] were included. CS was defined as C2-C7 coronal Cobb angle ≥10°. RESULTS:Totally, 114 patients were included (mean age 62.5 yr, 51.8% female). Fourteen patients (12.3%) had combined CS and CK, and 100 patients (87.7%) had CK alone. Preoperative maximum cervical coronal Cobb angle was 3.9° in the CK alone group and 14.6° in the combined CS and CK group. In the combined CS and CK group, this value improved to 8.1° postoperatively ( P =0.0007 vs. preoperative), but CS ≥10° was still present in three patients, with a mean correction percentage of only 48.0% of initial CS.No significant differences were observed between the CK only and combined CS and CK groups with regard to baseline sagittal parameters, change between immediate postoperative and baseline sagittal parameters, surgical approach, age, or baseline HRQOL. Patients with combined CS and CK were more frequently female than patients with CK alone (85.7% vs. 41.2%, P =0.0066). CONCLUSIONS:The vast majority of patients presented with CK alone (88%), and only 12% of adult CD patients had combined CS and CK. Because of the significant residual coronal plane deformity-∼50%-surgical correction should be focused on both coronal and sagittal plane deformity in the combined CS and CK group.

STUDY DESIGN/METHODS:Retrospective cohort analysis. OBJECTIVE:Assess the distribution of Medicare's spinal-deformity-specific diagnosis-related group (DRGs) relative to surgical invasiveness, hospital length of stay (LOS), discharge disposition, 90-day postoperative quality metrics, and reimbursement costs for adult spinal deformity (ASD) operations. SUMMARY OF BACKGROUND DATA/BACKGROUND:Heterogeneity of ASD call into question Medicare's DRGs to accurately capture nuances of ASD surgical episodes of care. METHODS:Adults who underwent thoracic to pelvis instrumentation with associated DRGs were identified from a multicenter database. Demographics, operative details, inpatient course, discharge disposition, 90-day adverse events, and reimbursement costs were compared between spinal deformity-specific DRG codes. Distribution of DRGs for a subset of these patients who fit into one of 6 commonly performed surgical strategies to address ASD was also assessed. RESULTS:Of the 314 patients included for analysis, the majority fell into +CC DRGs, while the minority had +MCC DRGs or no MCC/CC DRG. Within each DRG, there was considerable heterogeneity in regard to patients' ages, ASA, CCI, frailty, surgical invasiveness, postoperative ICU/hospital LOS, discharge disposition, and complication profiles.+MCC DRGs had significantly greater ASA and Edmonton Frailty Scores. While +MCC and +CC had relatively similar surgical invasiveness, +MCC had greater ICU admissions, in-hospital adverse events, and nonhome discharges as well as longer ICU, hospital, and rehab LOS. While reimbursements were significantly higher for +MCC DRG compared with +CC DRGs and DRGs without MCC/CC, there were large ranges in reimbursement within all DRG subgroups.The 7 DRGs varied significantly within and between the subset of 6 commonly performed surgical strategies, although there were no differences in regard to ICU admissions and LOS, hospital LOS, discharge disposition, and number of adverse events (in-hospital, 90-day). CONCLUSIONS:While Medicare's spinal-deformity DRG codes capture average trends in surgical/postoperative episodes of care for ASD patients, each encompasses highly heterogeneous patients and associated surgical operations rendering them unreliable gauges of patient/surgical complexity, early postoperative trajectories, and reimbursement costs. A more granular system is needed to more accurately capture the nuances of ASD operations and their associated quality metrics and reimbursement costs.

OBJECTIVE:The objective of this study was to determine whether increased cell saver (CS) salvage transfusion to estimated blood loss (EBL) ratio (CS:EBL) is a driver in the development of cardiopulmonary (CP) and/or renal complications. METHODS:Patients with adult spinal deformity (ASD) enrolled in a multicenter, observational prospective study from 13 spinal deformity centers in North America were queried. Eligible participants met at least one of the following radiographic and/or procedural inclusion criteria: pelvic incidence-lumbar lordosis mismatch ≥ 25°, T1 pelvic angle ≥ 30°, sagittal vertical axis ≥ 15 cm, thoracic scoliosis ≥ 70°, thoracolumbar/lumbar scoliosis ≥ 50°, global coronal malalignment ≥ 7 cm, having undergone a 3-column osteotomy, spinal fusion ≥ 12 levels, and/or age ≥ 65 years with ≥ 7 levels of instrumentation. Patients were dichotomized based on whether their CS:EBL was ≥ or < 0.33. Patients who did not have CS transfused intraoperatively were excluded. Key outcomes included renal and CP-related medical complications. Patient characteristics, preoperative laboratory results, operative data, and radiographic parameters were compared using appropriate statistical tests. A conceptual multivariable logistic regression model was built to assess risk factors associated with the primary outcome. RESULTS:Four hundred six patients were included in this analysis, including 10.6% (n = 43) with a CS:EBL ≥ 0.33 and 89.4% (n = 363) with a CS:EBL < 0.33. The patients with a CS:EBL ≥ 0.33 were significantly older (mean 66.2 [SD 12.2] vs 58.9 [SD 16.4] years, p = 0.0007), experienced less EBL intraoperatively (mean 1048.3 [SD 852.2] vs 1695.6 [SD 1295.3] ml, p < 0.0001), had fewer total instrumented levels (mean 12.2 [SD 3.3] vs 14.1 [SD 3.6] levels, p = 0.0001), had fewer posterior column osteotomies performed (72.1% vs 86.8%, p = 0.0103), and had less major coronal Cobb angle correction (mean -17.0° [SD 14.6°] vs -22.7° [SD 16.7°], p = 0.0373). Despite comparable transfusion rates, patients with a CS:EBL ≥ 0.33 had fewer packed red blood cell (RBC), fresh frozen plasma, and platelet units transfused intraoperatively (p < 0.05). No significant differences were observed among overall CP and renal complications. However, when stratifying CP complications by type, patients with a CS:EBL ≥ 0.33 experienced a significantly greater rate of pulmonary embolisms (PEs; 9.3% vs 1.4%, p = 0.0093) within 30 days of surgery. A multivariable logistic regression model adjusted for the significant differences between the two groups found a CS:EBL ≥ 0.33 to be an independent risk factor for the development of a PE, conferring an odds ratio of 6.57 (95% CI 1.75-24.66) with excellent model diagnostics (model p value = 0.0031, area under the receiver operating characteristic curve = 0.92). CONCLUSIONS:Patients with a high CS:EBL were at a significantly greater risk of developing a PE within the early postoperative period independent of blood loss and operative complexity. The findings support the re-evaluation of salvaged RBC use in this patient population based on perceived benefits.

PURPOSE/OBJECTIVE:A subset of adult spinal deformity (ASD) patients undergoing corrective surgery receive a disproportionate level of medical resources and incur greater costs. We examined the characteristics of such super-utilizers of health care resources among ASD patients. METHODS:This prospective, multicenter study analyzed data from ASD patients with > 4 levels of spinal fusion and a minimum 2-year follow-up. Index and total episode-of-care (EOC) costs in 2022 US dollars were calculated using average itemized direct costs obtained from administrative hospital records. Patients with total 2-year EOC cost > 90th percentile were considered super-utilizers, the characteristics of which we identified through a multivariate generalized logistic model. RESULTS:Of 1299 eligible patients, mean age was 60 years, 73% were female and 92% were Caucasian. Super-utilizers were older (+2.1 years; p = 0.012), had greater depression (34.2 vs 25.7%; p = 0.03), increased frailty (p = 0.009) comorbidities (p = 0.005), higher reoperation rates (54.4 vs 15.0%; p < 0.001), hospital length of stay (+ 3 days; p < 0.0001), higher surgical invasiveness (+28.6; p < 0.001), more vertebrae fused (+ 3; p < 0.0001); interbody fusions (80 vs 55%; p < 0.0001), bone morphogenetic protein (BMP) use (87.3 vs 69.4%; p = 0.0001), operative time (+91 min; p < 0.0001), and blood loss (+620 mL; p < 0.0001) compared to other ASD patients. Index cost was 65% (p < 0.0001), and cost/quality-adjusted life-year was three times higher among super-utilizers. CONCLUSION/CONCLUSIONS:ASD patients with depression who undergo more complex or revision spinal surgical procedures are more likely to be super-utilizers. Identifying likely super-utilizers within the ASD population may enable targeted interventions and preoperative planning to reduce unnecessary costs, while improving patient outcomes.

STUDY DESIGN/METHODS:Prospective, multi-center analysis. OBJECTIVE:Evaluate preoperative and minimum 2-year postoperative health related quality of life (HRQOL) outcomes for adult spine deformity (ASD) using legacy HRQOL measures and computer adaptive testing (CAT) version of the patient reported outcome measurement information system (PROMIS). SUMMARY OF BACKGROUND DATA/BACKGROUND:PROMIS is the NIH recommended measure for patient reported outcomes. No data exists evaluating minimum 2-year ASD surgical outcomes using PROMIS CAT compared to legacy HRQOL measures. METHODS:ASD patients > 18 years of age were enrolled into a prospective, multi-center, observational study. Patients were administered legacy HRQOLs (SRS-22r, ODI, NRS back and leg pain, VR-12) and PROMIS CAT for Pain Interference, Physical Function, Satisfaction with Participation in Social Roles, Satisfaction with Participation in Discretionary Social Activities, Depression, and Anxiety. Preoperative and minimum 2-year postoperative HRQOL scores were compared and ASD PROMIS scores were compared to general population PROMIS values. RESULTS:144 of 190 patients had complete data at minimum 2-year follow-up. Mean preoperative values included: age=62.6 years, scoliosis=34.2°, SVA=74.2mm, PI-LL=16.7. At mean 2.3 year follow-up surgical treatment improved spine alignment (scoliosis=14.7°, SVA=34.5mm, and PI-LL=4.5°; P<0.0001). All legacy HRQOL and PROMIS scores improved from preoperative to minimum 2-year postoperative (P<0.005). Referencing PROMIS scores to normative values demonstrated 50-85% of ASD patients preoperatively reported moderate-severe deficits in all domains. At minimum 2-year postoperative 52-88% of ASD patients reported normal values-mild deficits in all PROMIS domains. PROMIS social health domains demonstrated the greatest improvement. CONCLUSION/CONCLUSIONS:This is the first study evaluating minimum 2-year ASD surgical outcomes using PROMIS CAT. ASD patients demonstrated postoperative improvements in all PROMIS health domains, with the social health domains improving most. The majority of ASD patients reported normal PROMIS values at minimum 2-years postoperative.

PURPOSE/OBJECTIVE:To compare the impact of lumbar lordosis correction achieved by cephalad versus caudal distribution on radiographic alignment and surgical outcomes among adult spinal deformity (ASD) patients. METHODS:Patients who underwent ASD surgery with uppermost instrumented vertebrae (UIV) at or above L1, had preoperative pelvic incidence-lumbar lordosis (PI-LL) > 10°, and had full-body radiographs available were included. Eligible patients were categorized by the focus of lordosis correction: caudal (L4-S1 lordosis between 35 and 45°) and cephalad lordosis-based correction. Patient demographics, preoperative and 2 years spinopelvic alignment and PROMs, and 2 years postoperative surgical complications were compared. RESULTS:In total, 187 (111 caudal and 76 cephalad) patients were included, with mean age of 66.2 years, 78.6% female, and mean frailty score of 3.6. Caudally-restored patients often had an upper thoracic UIV, sacrum/ilium LIV, longer length of fusion, and no lateral lumbar interbody fusion (LLIF) while cephaladly-restored patients had two or more LLIFs above L4 (p < 0.001). Preoperatively, there were no significant differences in radiographic alignment and PROMs between the two groups (p > 0.02). Two years postoperatively, caudally-restored patients had higher L1-S1 LL (p = 0.015) and L4-S1 LL (p < 0.001), and lower PI-LL (p = 0.039) and SVA (p = 0.001). In addition, they had higher SRS-22 activity (p = 0.045), pain (p = 0.047), appearance (p = 0.046), and total (p = 0.016) scores. Finally, they had lower rates of sensory deficits (p < 0.001), motor deficits (p = 0.003), implant failure (p = 0.092), and reoperation (p = 0.020). CONCLUSION/CONCLUSIONS:Caudal lordosis-based correction of spinal deformity patients was associated with higher PROMs and lower rates of neurologic deficits, implant failure, and revisions at 2 years. These findings, while subject to unmeasured confounding, indicate that great caution should be taken when considering cephalad-based correction of ASD.