Radiographic Outcomes and Complications of Anterior Column Realignment (ACR): A Systematic Review.

BACKGROUND: Anterior Column Realignment (ACR) was introduced to serve as a powerful segmental kyphosis correction technique in minimally invasive Adult Spinal Deformity (ASD) surgery. Releasing the Anterior Longitudinal Ligament (ALL) and annulus allows opening of the disc space to accommodate hyperlordotic cages. The overall safety and efficacy of ACR has been difficult to determine due to the heterogenicity of surgical techniques, complications reporting, and a paucity of published studies leading to preliminary and controversial conclusions. PURPOSE: To determine the efficacy and complications rates associated with ACR. STUDY DESIGN: Systematic Review METHODS: : We queried the MEDLINE, Google Scholar, and EMBASE databases for all literature related to ACR procedure with a publication cutoff start date of January 1, 2010. This systematic review was performed utilizing the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Non-English, nonhuman, case reports and review article publications were excluded. RESULTS: A total of 298 studies were identified. Following screening of title, abstract, and full text, 16 articles were included in the review with a total 756 patients. All the studies included in this systematic review were retrospective case series with a level of evidence IV. Ten studies reported ACR-related complications, with an average rate of 27.2%. The rate of reoperations was reported in 5 studies, for which the average reoperation rate was 9.5%. Cage Subsidence (CS) occurred in 13.7%, Proximal Junctional Kyphosis (PJK) in 12.2%, neurologic injury in 7.3%, and Proximal Junctional Failure (PJF) in 2.7%. The vascular injury rate was 0.5%, with bowel perforation and ureteric injury occurring in 0.2%. For the Patient Reported Outcome Measures (PROMs) and radiological outcome analysis we excluded studies with less than 12 months follow up leaving 8 studies eligible for the analysis. There was a significant improvement of both local Motion Segment Angle (MSA) and Intra Discal Angle (IDA) with a mean segmental correction of 20° lordosis in the 3 studies that reported these parameters. CONCLUSION: Based on the limited data available in this systematic review, the ACR technique has significant ability to restore and, when needed, correct the local segmental intervertebral angulation and thereby influencing the overall regional and global sagittal alignment. The associated risk of vascular, bowel, and nerve injury did not seem to be significantly higher in this review than other alternative lumbar interbody fusion techniques. Additional higher quality studies, including a consensus for reporting complications is required to reach definitive conclusions regarding its possible associated risks.

Calculation of the minimal clinically important difference in operated patients with adult spine deformity: advantages of the ROC method and significance of prevalence in threshold selection.

PURPOSE: The Minimal Clinically Important Difference (MCID) is crucial to evaluate management outcomes, but different thresholds have been obtained in different works. Part of this variability is due to measurement error and influence of the database, both essential for calculating the MCID. The aim of this study was to introduce the association of the ROC method in the anchor-based MCID calculation for ODI, SRS-22r, and SF-36, to objectively set the threshold for the anchor-based MCID in an adult spine deformity (ASD) population. METHODS: Multicentric study based on a prospective database of consecutively operated ASD patients. An anchor question was used to assess patients' quality of life after surgery. Different approaches were used to calculate the MCID and then compared: SEM (Standard Error of Measurement), MDC (Minimal Detectable Change), and anchor-based MCID with ROC method. RESULTS: 516 patients were included. Those who responded with 6 and 7 to the anchor question were considered improved. The MCID ranges obtained with the ROC method exhibited the lowest variability. Prediction error rates ranged from 31% (SRS-22r) to 41% (SF-36 MCS). The MCID ranges spanned between 12 and 15 for ODI, 0.6 and 0.73 for SRS-22r, 6.62 and 7.41 for SF-36 PCS, and between 2.69 and 5.63 for SF-36 MCS. CONCLUSION: The ROC method proposes an MCID range with error rate, and can objectively determine the threshold for distinguishing improved and non-improved patients. As the MCID correlates with the utilized database and error of measurement, each study should compute its own MCID for each PROM to allow comparison among different publications. LEVEL OF EVIDENCE: II.

Contemporary utilization of three-column osteotomy techniques in a prospective complex spinal deformity multicenter database: implications on full-body alignment and perioperative course.

BACKGROUND: Research has focused on the increased correction from a three-column osteotomy (3CO) during adult spinal deformity (ASD) surgery. However, an in-depth analysis on the performance of a 3CO in a cohort of complex spinal deformity cases has not been described. STUDY DESIGN/SETTING: This is a retrospective study on a prospectively enrolled, complex ASD database. PURPOSE: This study aimed to determine if three-column osteotomies demonstrate superior benefit in correction of complex sagittal deformity at the cost of increased perioperative complications. METHODS: Surgical complex adult spinal deformity patients were included and grouped into thoracolumbar 3COs compared to those who did not have a 3CO (No 3CO) (remaining cohort). Rigid deformity was defined as ΔLL less than 33% from standing to supine. Severe deformity was defined as global (SVA > 70 mm) or C7-PL > 70 mm, or lumbopelvic (PI-LL > 30°). Means comparison tests assessed correction by 3CO grade/location. Multivariate analysis controlling for baseline deformity evaluated outcomes up to six weeks compared to No 3CO. RESULTS: 648 patients were included (Mean age 61 ± 14.6 years, BMI 27.55 ± 5.8 kg/m2, levels fused: 12.6 ± 3.8). 126 underwent 3CO, a 20% higher usage than historical cohorts. 3COs were older, frail, and more likely to undergo revision (OR 5.2, 95% CI [2.6-10.6]; p < .001). 3COs were more likely to present with both severe global/lumbopelvic deformity (OR 4), 62.4% being rigid. 3COs had greater use of secondary rods (OR 4st) and incurred 4 times greater risk for: massive blood loss (> 3500 mL), longer LOS, SICU admission, perioperative wound and spine-related complications, and neurologic complications when performed below L3. 3COs had similar HRQL benefit, but higher perioperative opioid use. Mean segmental correction increased by grade (G3-21; G4-24; G5-27) and was 4 × greater than low-grade osteotomies, especially below L3 (OR 12). 3COs achieved 2 × greater spinopelvic correction. Higher grades properly distributed lordosis 50% of the time except L5. Pelvic compensation and non-response were relieved more often with increasing grade, with greater correction in all lower extremity parameters (p < .01). Due to the increased rate of complications, 3COs trended toward higher perioperative cost ($42,806 vs. $40,046, p = .086). CONCLUSION: Three-column osteotomy usage in contemporary complex spinal deformities is generally limited to more disabled individuals undergoing the most severe sagittal and coronal realignment procedures. While there is an increased perioperative cost and prolongation of length of stay with usage, these techniques represent the most powerful realignment techniques available with a dramatic impact on normalization at operative levels and reciprocal changes.

Post-operative shift in pain profile following fusion surgery for adult spinal deformity: a cluster analysis.

PURPOSE: Adult spinal deformity (ASD) is associated with a combination of back and leg pain of various intensities. The objective of the present study was to investigate the diverse reaction of pain profiles following ASD surgery as well as post-operative patient satisfaction. METHODS: Multicenter surveillance collected data for patients ≥ 19 years old who underwent primary thoracolumbar fusion surgery at > 5 spinal levels for ASD. Two-step cluster analysis was performed utilizing pre-operative numeric rating scale (NRS) for back and leg pain. Radiologic parameters and patient-reported outcome (PRO) scores were also obtained. One-year post-operative outcomes and satisfaction rates were compared among clusters, and influencing factors were analyzed. RESULTS: Based on cluster analysis, 191 ASD patients were categorized into three groups: ClusterNP, mild pain only (n = 55); ClusterBP, back pain only (n = 68); and ClusterBLP, significant back and leg pain (n = 68). ClusterBLP (mean NRSback 7.6, mean NRSleg 6.9) was the oldest 73.4 years (p < 0.001) and underwent interbody fusion (88%, p < 0.001) and sacral/pelvic fixation (69%, p = 0.001) more commonly than the other groups, for the worst pelvis incidence-lumbar lordosis mismatch (mean 43.7°, p = 0.03) and the greatest sagittal vertical axis (mean 123 mm, p = 0.002). While NRSback, NRSleg and PRO scores were all improved postoperatively in ClustersBP and BLP, ClusterBLP showed the lowest satisfaction rate (80% vs. 80% vs. 63%, p = 0.11), which correlated with post-operative NRSback (rho = -0.357). CONCLUSIONS: Cluster analysis revealed three clusters of ASD patients, and the cluster with the worst pain back and leg pain had the most advanced disease and showed the lowest satisfaction rate, affected by postoperative back pain.

The Effect of Anaemia on Intra-operative Neuromonitoring Following Correction of Large Scoliosis Curves: Two Case Reports.

The correction of anemia is important in reversing significant intraoperative bilateral motor-evoked potential (MEP) loss following rod placement for correction of large scoliosis curves. This article presents a retrospective review of intraoperative neuromonitoring (IONM) data, anesthesia records, and medical charts of two patients with significant bilateral MEP changes associated with posterior spinal surgery for deformity correction. A 70 kg 12-year-old and a 44 kg 16-year-old female with main thoracic curves underwent a posterior scoliosis correction with multilevel posterior column osteotomies. Following rod insertion, significant reduction in the bilateral lower extremity MEP occurred in both cases despite mean arterial pressure exceeding 70 mmHg, which was presumed to be due to the scale of the correction attempted in the setting of haemorrhage which rendered the patient acutely anaemic, thus compromising cord vasculature and oxygen delivery. The rods were removed and packed red blood cell transfusions were administered in response to acute anaemia as a result of haemorrhage in both cases. Neither was noted to be anaemic preoperatively. Once the MEP signals improved, the rods were reinserted and correction was attempted, limited by neuromonitoring signals and resistance of the bony anchors to pullout. At closure, the MEPs were near baseline in the first case and >50% of baseline in the second. There were no changes in the somatosensory evoked potential signals in either case. Post-operative neurological function was normal in both patients. Correcting the circulating haemoglobin concentration through blood product resuscitation allowed for safe correction of spinal deformity in two cases with significant bilateral MEP loss following the initial placement of rods.

The Role of Anterior Spine Surgery in Deformity Correction.

There are a range of anterior-based approaches to address flexible adult spinal deformity from the thoracic spine to the sacrum, with each approach offering access to a range of vertebral levels. It includes the transperitoneal (L5-S1), paramedian anterior retroperitoneal (L3-S1), oblique retroperitoneal (L1-2 to L5-S1), the thoracolumbar transdiaphragmatic approach (T9-10 to L4-5), and thoracotomy approach (T4-T12). The lumbar and lumbosacral spine is especially favorable for anterior-based approaches given the relative mobility of the peritoneal organs and position of the vasculature.

Antibiotic Use in Adult Spine Deformity Surgery: Results From the AO Spine Surveillance of the Management of Patients With Adult Spine Deformity.

STUDY DESIGN: Cross-sectional international survey with literature review. OBJECTIVES: To evaluate the evidence for these strategies and to understand the current trends in prophylactic antibiotic use during ASD surgery through an international survey. METHODS: An online survey was conducted among international AO Spine members regarding the peri-operative management of patients with ASD. The details of perioperative systemic and topical antibiotic use were solicited. Descriptive data were summarized for the responding surgeons who perform at least 10 long-segment fusions of >5 levels extending to the pelvis annually. RESULTS: The literature supports the use of prophylactic antibiotic effective against gram positive organisms. The use of topical vancomycin remains debated, and there is limited evidence for topical tobramycin use. A total of 116 responses were received. 74 (64%) surgeons use topical vancomycin, most usually deep to the fascia only 45 (61%). The most usual dose used is 1-2 g. 4 (3%) surgeons use topical tobramycin deep to fascia. Following surgery, 90 (78%) surgeons use prophylactic cephalosporin with 3 (3%) using cloxacillin, 5 (4%) using ciprofloxacin and 9 (8%) using vancomycin and 6 (5%) using clindamycin either in addition or alone. CONCLUSIONS: The present survey identifies a trend towards systemic and topical antibiotic prophylaxis primarily targeted at gram positive pathogens. The use of topical tobramycin, proposedly effective against gram negative infections, remains uncommon. There is a lack of consensus in the selection of perioperative antibiotic prophylaxis, thus a prospective study of the rates of infection with each strategy would be useful to inform guidelines.

Fixed coronal malalignment (CM) in the lumbar spine independently impacts disability in adult spinal deformity (ASD) patients when considering the obeid-CM (O-CM) classification.

BACKGROUND: Postoperative flatback has been described in detail for sagittal plane considerations over the past 2 decades, and its correlations with disability are now accepted. Fixed Coronal Malalignment (CM) has been less described, and some authors report no significant association with the clinical outcome. The O-CM classification analyses CM and incorporates specific modifiers for each curve type. PURPOSE: This study evaluates the O-CM classification modifiers according to age, sagittal alignment, and patient-reported outcome measures (PROMs). Our hypothesis is that fixed CM correlates with PROMs independently from sagittal alignment and age. STUDY DESIGN: Retrospective analysis of a large adult spinal deformity (ASD) database prospectively collected. PATIENT SAMPLE: We included 747 patients from the database with long lumbar fusion (more than 3 levels), with at least two years of follow-up. Three categories of patients met the inclusion criteria (prior surgery at baseline and no revision surgery afterward, prior surgery at baseline and revision afterward, no prior surgery at baseline but fusion>3 levels and 2 years follow-up). OUTCOME MEASURES: All patients completed the Oswestry Disability Index (ODI), Short Form 36 (SF36), and Scoliosis Research Society 22 scores. METHODS: The patients were classified according to the six modifiers of the O-CM classification. Central Sacral Vertical Line (CSVL) above 2, 3, and 4 cm's impact on PROMs was analyzed. Multivariate analysis was performed on the relationship between PROMS and age, global tilt (GT), and CM modifiers. RESULTS: After multivariate analysis using age and GT as confounding factors, we found that CM independently affects PROMs starting at 2 cm offset. Disability increases linearly with CSVL. Patients classified with 2B modifiers have the worst SRS-22 total score, social life, and self-image. CONCLUSION: In a fused spine, CM independently affects disability in ASD patients. Disability increases linearly with CSVL. Despite previous reports that failed to find correlations of CM with PROMs, our study showed that fixed postoperative CM, according to O-CM classification, correlates independently from sagittal malalignment with worse PROMs. LEVEL OF EVIDENCE: III.

Utility of Expandable Interbody Cages in Open Transforaminal Interbody Fusions: A Comparison With Static Cages.

Background Expandable interbody cages, while popular in minimally invasive fusions due to their slim profile and increased ease of insertion, have not been widely explored in open surgery. The benefits of expandable cages may also extend to open fusions through their potential to achieve a greater restoration of lumbar lordosis while minimizing intraoperative complications. To highlight these benefits, we present a case series of adult spinal deformity (ASD) patients treated with an open transforaminal lumbar interbody fusion (TLIF) using expandable cages and compare outcomes to those of patients treated with static cages from the literature. Methods A retrospective cohort study of patients who underwent a deformity correction procedure and TLIF with expandable interbody cages at Brigham and Women's Hospital between 2018 and 2022 was conducted. Patient demographics, complications, and pre- and postoperative radiographic parameters of spinopelvic alignment were collected. A literature search was completed to identify studies employing static cages. T-tests were performed to compare postoperative changes in radiographic parameters by cage type. Results Forty-five patients (mean age of 62.6 years) with an average of 2.1 cages placed met the inclusion criteria. Patients experienced five intraoperative complications and 23 neurologic deficits (from minor to major), while nine patients required a revision operation. Lumbar lordosis increased by 9.8° ± 14.5° (p < 0.0001), the sagittal vertical axis (SVA) decreased by 25.5 mm ± 56.7 mm (p = 0.0048), and pelvic incidence-lumbar lordosis mismatch decreased by 13.3° ± 17.5° (p < 0.0001) with the use of expandable cages. Expandable cages yielded similar changes in lumbar lordosis to 15° and 8° cages but improved the lumbar lordosis generated from rectangular and 4° cages. When compared to static cages, expandable cages mildly reduced intraoperative complications. Conclusions Expandable interbody cages are an effective means of restoring spinopelvic alignment in ASD that have the potential to improve patient outcomes in open fusions compared to standard static cages. Especially when compared to rectangular and 4° static cages, expandable cages provide a clear benefit in the correction of lumbar lordosis. The impact of open spinal fusions with expandable cages on outcomes should continue to be explored in other cohorts.

Two- versus multi-rod constructs for adult spinal deformity: A systematic review and Random-effects and Bayesian meta-analysis.

BACKGROUND: Surgical approaches in adult spinal deformity are associated with high rates of adverse events including hardware failure and rod fracture. Recently, some reports have emerged comparing multiple-rod constructs with 2-rod constructs suggesting potential benefits with the former. However, these have been limited by variability in observed outcomes, which have limited the change of paradigm in adult spinal deformity surgery. OBJECTIVE: To compare the rate of rod fracture, pseudoarthrosis, proximal junctional kyphosis and re-operation between 2-RC and M-RC. METHODS: MEDLINE/Pubmed, Web of Science and Embase were searched without language restrictions for relevant articles from inception until October 2021. All observational cohort studies assessing patients with ADS undergoing 3-column osteotomy and comparing 2-RC with M-RC procedures on pseudarthrosis, rod fracture, kyphosis or reoperation were included. Data were independently extracted by 2 authors. Random-effects and Bayesian meta-analysis were used. RESULTS: Six primary studies met inclusion criteria, yielding a total of 448 participants, with 223 receiving 2-RC and 225 M-RC. The random-effects meta-analysis pointed to a significantly lower risk of rod fracture associated with M-RC (RR = 0.43, 95 %CI = 0.28-0.66), with moderate heterogeneity being observed (I2 = 20 %, p = 0.28). The random-effects meta-analysis pointed to a lower risk of pseudoarthrosis with M-RC than with 2-RC (RR = 0.49, CI = 0.28-0.84, to a lower rate of re-operation with M-RC than with 2-RC (RR = 0.52, CI = 0.28-0.97) and to a similar rate of proximal junctional kyphosis between 2-RC and M-RC patients (RR = 0.91, CI = 0.60-1.39). Low heterogeneity was observed for studies comparing pseudoarthrosis (I2 = 9 %, p = 0.35), re-operation (I2 = 0 %, p = 0.41) and proximal junctional kyphosis (I2 = 0 %, p = 0.85). DISCUSSION: These findings suggest that multiple rod-fracture constructs are associated with lower rates of rod fracture, re-operation rates, pseudoarthrosis but not proximal junctional kyphosis. Future studies should address the impact of other modulators of heterogeneity such as body mass index, metal alloys and length of the constructs.

Postoperative coronal malalignment after adult spinal deformity surgery: incidence, risk factors, and impact on 2-year outcomes.

PURPOSE: To evaluate the incidence, risk factors, and patient-reported outcomes (PROs) of adult spinal deformity (ASD) patients with postoperative coronal malalignment. METHODS: A single-institution, retrospective cohort study of ASD patients undergoing ≥ 6 level fusions from 2015 to 2019 was undertaken. The primary outcome was postoperative coronal malalignment, defined as C7-coronal vertical axis (CVA) > 3 cm. Secondary outcomes included: complications, readmissions, reoperations, and 2-year PROs. RESULTS: A total of 243 ASD patients undergoing spinal surgery had preoperative and immediate postoperative measurements, and 174 patients (72%) had 2-year follow-up. Mean age was 49.3 ± 18.3yrs and mean instrumented levels was 13.5 ± 3.9. Mean preoperative CVA was 2.9 ± 2.7 cm, and 90 (37%) had preoperative coronal malalignment. Postoperative coronal malalignment occurred in 43 (18%) patients. Significant risk factors for postoperative coronal malalignment were: preoperative CVA (OR 1.21, p = 0.001), preoperative SVA (OR 1.05, p = 0.046), pelvic obliquity (OR 1.21; p = 0.008), Qiu B vs. A (OR 4.17; p = 0.003), Qiu C vs. A (OR 7.39; p < 0.001), lumbosacral fractional (LSF) curve (OR 2.31; p = 0.021), max Cobb angle concavity opposite the CVA (OR 2.10; p = 0.033), and operative time (OR 1.16; p = 0.045). Postoperative coronal malalignment patients were more likely to sustain a major complication (31% vs. 14%; p = 0.01), yet no differences were seen in readmissions (p = 0.72) or reoperations (p = 0.98). No significant differences were seen in 2-year PROs (p > 0.05). CONCLUSIONS: Postoperative coronal malalignment occurred in 18% of ASD patients and was most associated with preoperative CVA/SVA, pelvic obliquity, Qiu B/C curves, LSF curve concavity to the same side as the CVA, and maximum Cobb angle concavity opposite side of the CVA. Postoperative coronal malalignment was significantly associated with increased complications but not readmission, reoperation, or 2-year PROs.

Do Adult Spinal Deformity Patients Undergoing Surgery Continue to Improve From 1-Year to 2-Years Postoperative?

OBJECTIVE: Evaluate clinical improvement as measured by patient-reported outcomes (PROs) during the 1 to 2-year interval. STUDY DESIGN: Retrospective Cohort. METHODS: A single-institution registry of ASD patients undergoing surgery was queried for patients with ≥6 level fusions. Demographics and radiographic variables were collected. PROs collected were the ODI and SRS-22r scores at: preoperative, 1-year and 2-years. Outcome measures of clinical improvement during the 1-2 year time interval were: 1) group medians, 2) percent minimum clinically important difference (MCID), and 3) percent minimal symptom scale (MSS)(ODI < 20 or SRS-pain + function >8). Wilcoxon rank-sum tests, chi-squared tests, Kruskal-Wallis tests, and logistic regression were performed. RESULTS: 157 patients undergoing ASD surgery with minimum of 1-year follow-up were included. Mean age was 53.2 and mean instrumented levels was 13.1. Preoperative alignment was: Neutral Alignment (NA) 49%, Coronal Malalignment (CM) 17%, Sagittal Malalignment (SM 17%), and Combined Coronal/Sagittal Malalignment (CCSM) 18%. Preoperative to 1-year, and preoperative to 2-years, all ODI/SRS-22r significantly improved (P < .001). In all patients, the only significant improvement in PROs between 1-and 2-year postoperative were those reaching ODI MCID (69% 1-year vs. 84% 2-years; P < .001). Subgroup analysis: ≥55 years had an improved median ODI (18 vs. 8; P = .047) and an improved percent achieving ODI MCID (73% vs. 84%, P = .048). CCSM patients experienced significant improvement in SRS-appearance score (75% vs. 100%; P = .050), along with those with severe preoperative SM >7.5 cm (73% vs. 100%; P = .032). CONCLUSIONS: Most ASD patients experience the majority of PRO improvement by 1-year postoperative. However, subsets of patients that may continue to improve up to 2-years postoperative include patients ≥55 years, combined coronal/sagittal malalignment, and those with severe sagittal malalignment ≥7.5 cm.

The Relationship Among Surgeon Experience, Complications, and Radiographic Outcomes in Spine Deformity Surgery: The Experience of a Junior Surgeon.

OBJECTIVE: To examine complication rates and radiographic outcomes in patients undergoing surgery for adult spinal deformity (ASD) by a junior surgeon. METHODS: A study was conducted of a retrospective cohort of patients who underwent an open posterior interbody fusion of the thoracic and/or lumbar regions by a single surgeon for ASD between 2018 and 2022. Patient characteristics, complications, and common radiographic parameters of spinopelvic alignment were collated. RESULTS: A total of 112 patients with an average of 4.2 comorbidities underwent surgical correction of ASD. Thirty-seven patients (33.0%) experienced 52 major complications and 50 patients (44.6%) experienced 66 minor complications. Twenty-three patients (20.5%) required a revision operation. Both sagittal vertical axis (P < 10-14) and pelvic incidence-lumbar lordosis mismatch (P < 10-7) significantly improved postoperatively. Number of levels (P < 0.05), operative time >650 minutes (P < 0.01), estimated blood loss >1500 mL (P < 0.01), length of intensive care unit stay >1 day (P < 0.05), and hospitalization length >5 days (P < 0.05) all significantly increased the risk of a major complication. No patient factors significantly increased the risk of minor complications or revision surgery. CONCLUSIONS: Observed complication and revision rates in this cohort were consistent with rates reported in the literature. No preoperative patient risk factors significantly increased risk of complications or need for revision, suggesting that no patient population is at increased risk undergoing surgery by a junior surgeon. The relatively high rate of complications observed in this cohort may be a result of high baseline morbidity.

Long spine fusions to the sacrum-pelvis are associated with greater post-operative proximal junctional kyphosis angle in sitting position.

STUDY DESIGN: A single-centre retrospective study. BACKGROUND AND PURPOSE: Although adult patients spend most of their time in sitting positions, the assessment of spinopelvic parameters in adult deformity surgery is commonly performed in standing X-rays. Our study compares the standing and sitting sagittal alignment parameters in subjects who underwent thoracolumbar fusion. METHODS: Patients who underwent corrective surgery for adult scoliosis with at least five instrumented vertebra were stratified according to the upper instrumented vertebra (UIV) and pelvic fixation. Group A:UIV proximal to T6 with pelvis fixation. B:UIV lower than T6 and pelvic fixation. Group C: thoracolumbar fusion without pelvic fixation. Post-operative spinopelvic sagittal parameters were measured in both standing and sitting X-rays. RESULTS: A total of 51 patients were enrolled in the study (11:Males and 40:Females). The mean age was 52.3 ± 21.7y/o. The comparison of post-operative standing and sitting X-ray within the group A and B showed that a significant change was observed in terms of JA-Junctional Angle-(Group A 6.3 ± 4.3 vs. 8.1 ± 3.3, p value = 0.03) (Group B 8.5 ± 6.4 vs. 10.9 ± 6.4, p value = 0.02). Group C showed statistically significant difference in terms of PT (15.6 ± 11.2 vs. 19.3 ± 9.2, p value = 0.04), AVA-Acetabular Version Angle-(41.1 ± 5.9 vs. 48.3 ± 6.6, p value < 0.01) and LL (- 51.3 ± 16.0 vs. - 42.6 ± 10.7, p value < 0.01). CONCLUSION: In our series, the post-operative sagittal alignment showed peculiar behaviours and adaptations in sitting position, depending on the length and the site of the instrumented area. If the pelvis is included, the JA tends to significantly increase in sitting position. These findings can improve the knowledge of pathologies as proximal junctional kyphosis or specific cases of anterior hip impingement. LEVEL OF EVIDENCE: IV.

Systematic review and meta-analysis for the impact of rod materials and sizes in the surgical treatment of adult spine deformity.

PURPOSE: To assess clinical and safety outcomes associated with different rod materials and diameters in adult spinal deformity (ASD) surgery. METHODS: A systematic literature review and meta-analysis evaluated ASD surgery using pedicle screw fixation systems with rods of different materials and sizes. Postoperative outcomes (i.e., Cobb, sagittal vertical axis, and pelvic tilt angle) and complications (i.e., pseudarthrosis and rod breakage) were assessed. Random effects models (REMs) pooled data for outcomes reported in ≥ 2 studies. RESULTS: Among 50 studies evaluating ASD surgery using pedicle screw fixation systems, 17 described rod material/diameter. Postoperative outcomes did not statistically differ between cobalt-chromium (CoCr) vs. titanium (Ti) rods (n = 2 studies; mean [95% confidence interval (CI)] sagittal vertical axis angle: CoCr 37.00° [18.58°-55.42°] and Ti 32.58° [24.62°-40.54°]; mean [95% CI] pelvic tilt angle: CoCr 26.20° [22.87°-29.53°] and Ti 20.15° [18.0°-22.31°]). The pooled proportion (95% CI) of pseudarthrosis was 15% (7-22%) for CoCr and 12% (- 8-32%) for stainless steel (SS) (n = 2 studies each; Chi2 = 0.07, p = 0.79). The pooled proportion (95% CI) of broken rods was 12% (1-22%) for Ti (n = 3 studies) and 10% (2-19) for CoCr (n = 1 study). Among 6.0-6.35 mm rods, the pooled (95% CI) postoperative Cobb angle (n = 2) was 12.01° (9.75°-14.28°), sagittal vertical axis angle (n = 4) was 35.32° (30.02°-40.62°), and pelvic tilt angle was 21.11° (18.35°-23.86°). CONCLUSIONS: For ASD patients undergoing posterior fixation and fusion, there are no statistically significant differences in postoperative outcomes or complications among rods of varying materials and diameters. Benchmark postsurgical outcomes and complication rates by rod material and diameter are provided. LEVEL OF EVIDENCE: III.

Determining the relationship between preoperative mental health scores and postoperative outcomes in adult spinal deformity surgeries.

OBJECTIVE: The objective of this study was to examine the relationship between the mental health domain of the refined 22-item Scoliosis Research Society Outcome Questionnaire (SRS) and various postoperative outcome measures in the adult spinal deformity (ASD) population. Given the scale and involved nature of deformity surgery, some surgeons have proposed that preoperative mental health scores (MHSs) may assist in screening out poor surgical candidates. In this study, the authors aimed to further assess the SRS MHS as a preoperative metric and its association with postoperative outcomes and to comment on its potential use in patient selection and optimization for ASD surgery. METHODS: The authors conducted a retrospective study of 100 consecutive patients who had undergone primary or revision ASD surgery at a single academic institution between 2015 and 2019. Each patient had a minimum 2-year follow-up. Patients were categorized on the basis of their baseline mental health per the SRS mental health domain, with a score < 4 indicating low baseline mental health (LMH) and a score ≥ 4 indicating high baseline mental health (HMH). Baseline and follow-up SRS and Oswestry Disability Index scores, surgical procedures, lengths of stay, discharge locations, intraoperative or postoperative complications, and other outcome metrics were then compared between the HMH and LMH groups, as well as these groups stratified by an age ≤ 45 and > 45 years. RESULTS: Among patients aged ≤ 45 and those aged > 45, the LMH group had significantly worse baseline health-related quality-of-life (HRQOL) metrics in nearly all domains. The LMH group also had an increased median estimated blood loss (EBL; 1200 vs 800 ml, p = 0.0026) and longer average surgical duration (8.3 ± 2.8 vs 6.9 ± 2.6 hours, p = 0.014). Both LMH and HMH groups had significant improvements in nearly all HRQOL measures postoperatively. Despite their worse preoperative HRQOL baseline, patients in the LMH group actually improved the most and reached the same HRQOL endpoints as those in the HMH group. CONCLUSIONS: While patients with lower baseline MHSs may require slightly longer hospital courses or more frequent discharges to rehabilitation facilities, these patients actually attain greater absolute improvements from their preoperative baseline and surprisingly have the same postoperative HRQOL metrics as the patients with high MHSs, despite their poorer starting point. This finding suggests that patients with LMH may be uniquely positioned to substantially benefit from surgical intervention and improve their HRQOL scores and thus should be considered for ASD surgery to an extent similar to patients with HMH.

Late spinal infections are more common after pediatric than after adult spinal deformity surgery.

PURPOSE: To compare the incidence, timing, and microbiologic factors associated with late spinal infection (onset ≥ 6 months after index operation) in pediatric versus adult spinal deformity patients who underwent instrumented posterior spinal fusion (PSF). METHODS: We retrospectively queried our institutional database for pediatric (aged ≤ 21 years) and adult patients who underwent instrumented PSF from 2000 to 2015. Inclusion criteria were > 12-month follow-up, spinal arthrodesis spanning 4 or more levels, and idiopathic or degenerative spinal deformity. We included 1260 patients (755 pediatric, 505 adult). Incidence, timing, and microbiologic and operative parameters of late spinal infections were compared using chi-squared and Fisher exact tests. Alpha = 0.05. RESULTS: Late spinal infection occurred in 28 (3.7%) pediatric and 2 (0.39%) adult patients (p = 0.009). Mean onset of infection was 4.2 years (range 0.7-12) in pediatric patients and 4.0 years (range 0.7-7.3) in adults (p = 0.93). Pediatric patients underwent arthrodesis spanning more levels (mean ± standard deviation, 10 ± 2.0) compared with adults (8.4 ± 3.3) (p < 0.001). Adults experienced greater intraoperative blood loss (2085 ± 1491 mL) compared with pediatric patients (796 ± 452 mL) (p < 0.001). Culture samples yielded positive growth in 11 pediatric and 2 adult cases. Propionibacterium and coagulase-negative staphylococci were the most commonly detected microorganisms in both cohorts. CONCLUSION: Late spinal infections were significantly more common in pediatric patients than in adults after instrumented PSF for spinal deformity. Skin and indolent microorganisms were the primary identifiable causative bacteria in both cohorts. LEVEL OF EVIDENCE: III.

The Effect of Discharging Patients with Low Hemoglobin Levels on Hospital Readmission and Quality of Life after Adult Spinal Deformity Surgery.

STUDY DESIGN: Retrospective cohort. PURPOSE: This study aims to evaluate the impact of anemia on functional outcomes, health-related quality of life (HRQoL), and early hospital readmission (EHR) rates after adult spinal deformity (ASD) surgery at the time of discharge from the hospital. OVERVIEW OF LITERATURE: Concerns with risks of transfusion, insufficient evidence for its benefits, and the possibility of associated adverse outcomes have led to restrictive transfusion practices. Therefore, patients are discharged according to patient blood management programs that are implemented in hospitals nationwide to reduce unnecessary blood transfusions. However, not many comprehensive kinds of studies exist on the effect of postoperative anemia on functional life and complications. METHODS: Anemia severity was defined following the 2011 World Health Organization guidelines. All patients had HRQoL tests as well as complete blood counts pre- and postoperatively. EHR is the admission within 30 days of discharge and was used as the dependent parameter. RESULTS: This study comprised 225 surgically treated ASD patients with a median age of 62.0 years, predominantly women (80%). Of the 225 patients, 82, 137, and six had mild, moderate, and severe anemia at the time of discharge, respectively. Seventeen of the patients (mild [11, 64.7%]; moderate [5, 29.4%]; severe [1, 5.9%]) were readmitted within 30 days. The mean hemoglobin values were higher in readmitted patients (p=0.071). Infection was the leading cause of readmission (n=12), but a low hemoglobin level was not observed in any of these patients at the time of discharge. Except for Scoliosis Research Society-22 questionnaire, HRQoL improvements did not reach statistical significance in early readmitted patients in the first year after surgery. CONCLUSIONS: The results of this study demonstrated that the occurrence and the severity of postoperative anemia are not associated with EHR in surgically treated patients with ASD. The findings of the current research suggested that clinical awareness of the parameters other than postoperative anemia may be crucial. Thus, improvements in HRQoL scores were poor in early readmitted patients 1 year after surgery.

The 90-Day Reoperations and Readmissions in Complex Adult Spinal Deformity Surgery.

STUDY DESIGN: Retrospective review. OBJECTIVE: Identify surgical complex adult spine deformity patients who are at increased risk for an unplanned postoperative 90-day readmission and/or reoperation. METHODS: A total of 227 consecutive records of complex adult (≥18 years old) spine deformity surgeries from 2015 to 2018 were reviewed. Demographics, comorbidities, operative details, and postoperative complication data was collected. Chi-square/Fisher's exact test and t tests were used for bivariate analysis. To determine independent predictors for readmissions/reoperations, stepwise multivariate logistic regressions were employed. The C-statistic and Hosmer-Lemeshow (HL) value was used to measure concordance and goodness of fit. RESULTS: Average age was 50.5 ± 17.8 years and 67.8% were female. Ninety-day readmission and reoperation rates were 7.0% and 5.3%, respectively. Median number of days after index discharge date resulting in readmission and reoperation were 16.5 and 28, respectively. The multivariate regression for 90-day readmissions included pulmonary comorbidity, depression, history of deep vein thrombosis/pulmonary embolism (DVT/PE), and gastrointestinal comorbidity (C-statistic = 0.82; HL = 0.79). Pulmonary comorbidity, depression, and history of DVT/PE increased risk for 90-day readmission by 5-, 3.5-, and 10.2-fold, respectively. The multivariate regression for 90-day reoperations was similar to readmissions (C-statistic = 0.89; HL = 0.31). Operative time>7 hours and history of DVT/PE increased risk for early reoperation by 5.8- and 8.7-fold, respectively. CONCLUSIONS: An emphasis on medically optimizing patients with preexisting pulmonary comorbidities, depression, and history of DVT/PE may have a substantial impact on improving short-term outcomes in this population. The present study provides benchmark data and may serve as an initial model to predict unplanned reoperations and readmissions.

Minimum 2-Year Analysis of S2-Alar-Iliac Screw Fixation for Adult Spinal Deformity.

STUDY DESIGN: Retrospective cohort. OBJECTIVE: Determine the rate and risk factors for S2AI screw-related pain after adult spinal deformity surgery with a minimum 2-year follow-up. METHODS: A consecutive 83 spinal deformity patients undergoing surgical treatment between August 2015 and December 2017 with minimum 2-year follow-up for S2AI screw complication and screw-related pain were included. Linear regression was performed on various risk factors and postoperative S2AI screw-related pain. Subset analysis of 53 patients was performed on preoperative and postoperative SRS and ODI scores, operative data, and radiographic data. RESULTS: The overall proportion of S2AI screw-related pain was 9.6%. An S2AI screw complication was identified radiographically in 10.8% of patients; among these, 22.2% experienced S2AI screw-related pain. 3.4% of all patients underwent S2A1 screw removal. The SRS, ODI, sagittal vertical axis (SVA), and coronal alignment scores/measurements improved following treatment in all patients. However, the mean difference for the pre and postoperative SRS function score (1.2 ± 0.5 vs 0.9 ± 0.8) and SVA (4.0 ± 4.9 cm vs 2.1 ± 4.8 cm) were higher for the pain group. CONCLUSIONS: A minimum 2-year analysis of S2AI screw fixation in adult spinal deformity patients showed that 9.6% of patients experienced S2AI screw-related pain and 3.4% of patients had S2A1 screws removed. The size and the number of S2AI screws did not predict postoperative pain, nor were radiographic findings correlated with clinical outcomes. The patient outcome scores, coronal alignment, and SVA improved for all patients, but within the pain group there was an overall larger change in the SVA and SRS function score.