Corrective Surgery For Adult Spinal Deformity Research Articles

Long-term Postural Stability Changes After Correction of Spinal Deformity: A prospective, controlled pilot study.

Prospective cohort study. This study aimed to investigate the durability of postural stability after ASD correction surgery and its' association with clinical outcomes. The prevalence of symptomatic adult spinal deformity (ASD) necessitates surgical intervention, aiming to correct global spinal balance and spinopelvic parameters. Short-term studies have shown improvements in postural control following surgery, but the long-term impact remains unclear. This single-center prospective cohort study included adult patients undergoing long-segment fusion surgery between November 2019 and July 2021. Preoperative and postoperative balance assessments, radiographic analyses, and patient-reported outcome measures (PROMs) were conducted. Statistical analyses evaluated changes in postural stability and clinical outcomes. Fifteen ASD patients were analyzed. Significant improvements were observed in the early postoperative period in coronal center of pressure (COP) sway (P=0.048) and amplitude (P=0.027), total COP sway (P=0.042), coronal center of gravity (COG) amplitude (P=0.013), total COG sway (P=0.044), and head sway in the coronal plane (P=0.025). These improvements were maintained at the final postoperative visit for all measurements except coronal COG amplitude (early vs. last postoperative visit, P=0.040). Radiographic parameters, including pelvic incidence - lumbar lordosis mismatch (P=0.041) and sagittal vertical axis (P=0.032), also significantly improved postoperatively. PROMs revealed significant enhancements in VAS back pain (P=0.045), RAND SF-36 pain (P=0.016), RAND SF-36 physical functioning (P=0.008), and PROMIS pain interference (P=0.032) scores at the last follow-up. These results demonstrate that the postural stability improvements seen after ASD correction are durable and correlate with enhanced clinical outcomes, such as reduced back pain and improved physical functioning. These findings underscore the clinical importance of achieving sagittal alignment in ASD patients. Further research with larger cohorts and extended follow-up periods is warranted to confirm these associations and establish postural stability assessment as a vital parameter in evaluating patients' quality of life postoperatively. Level 3.

The predictive power of the Roussouly classification on mechanical complications after surgery for adult spinal deformity: systematic review and meta-analysis.

With the increasing prevalence of adult spinal deformity (ASD) in the aging population, the need for corrective surgery has surged, highlighting the importance of preventing mechanical complications (MC) such as junctional kyphosis/failure and rod breakage. The Roussouly classification, which categorizes natural variations in spinal posture, may hold predictive value in assessing the risk of these complications, as it guides the restoration of sagittal alignment based on a patient's preoperative spinal shape. PubMed, Cochrane, and Google Scholar (pages 1-20) were searched through August 2024 to find articles comparing the incidence of mechanical complications between patients who were matched and mismatched to their ideal Roussouly shape after surgery for ASD. Extracted data consisted of the risk of mechanical complications, and the risk of reoperations. 10 retrospective studies were included in this meta-analysis, with 1454 patients divided into 2 groups, the first group matching Roussouly classification (716 patients, 49%) and the second unmatched (738 patients, 51%). A 5-times lower rate of mechanical complication (Odds-Ratio = 0.22; 95% CI: 0.12-0.41, p < 0.001) was found in the matched group at an average follow-up of 3.6 years. Furthermore, when examining specific mechanical complications, there were higher rates of both PJK (Odds-Ratio = 1.59; 95% CI: 1.07-2.38, p = 0.02) and rod breakages (Odds-Ratio = 1.75; 95% CI: 1.15-2.66, p = 0.01) in the unmatched group. However, no difference in the rate of reoperations was observed between the two groups (Odds-Ratio = 0.48; 95% CI: 0.18-1.28, p = 0.14). Matching patients to their ideal Roussouly type in adult spinal deformity surgery significantly reduces mechanical complications making it a secure and efficient method. Future studies should compare the Roussouly classification to other alignment models to determine optimal alignment for ASD correction surgery. III.

Which components of the global alignment proportionality score have the greatest impact on outcomes in adult spinal deformity corrective surgery?

To investigate the impact of the Global Alignment and Proportion (GAP) score components on patient outcomes in Adult Spine Deformity (ASD) surgery. Patients included underwent assessment via the GAP score and its individual components: pelvic version (GAP PV), lumbar lordosis (GAP LL), lumbar distribution index (GAP LDI) and spinopelvic component (GAP SP). Multivariable analyses assessed the association between alignment in these components and clinical outcomes in ASD patients. 762 ASD patients met inclusion criteria. Alignment in GAP SP independently predicted meeting MCID for SR-22S and ODI and was associated with a lower likelihood of developing mechanical complications. Patients aligned in GAP SP were less likely to develop proximal junctional kyphosis (OR 0.42, 0.26-0.73, p = 0.01) and PJF (OR 0.3, 0.13-0.74, p = 0.01). Proportioned alignment in GAP SP with disproportioned alignment in GAP LDI contributed to an increased risk of PJK and PJF (OR 2.67, 95% CI 1.95-6.82, p = 0.045). There was no significant association of GAP SP proportionality and GAP RPV (OR 1.1, 0.86-2.15, p = 0.253) or GAP LL (OR 1.34, 0.78-4.23, p = 0.673) disproportionality with outcomes. Disproportioned alignment in GAP SP but proportioned alignment in both GAP LL and GAP LDI was associated with decreased likelihood of PJK (OR 0.53, 95% CI 0.39-0.94, p = 0.02) and PJF (OR 0.31, 95% CI 0.19-0.67, p = 0.001). The spinopelvic component of the GAP score is the most significant independent predictor of clinical outcomes. Its interaction with the other components of the GAP score also aids assessment of the risk for mechanical complications.

Do Obese Patients Have Worse Outcomes in Adult Spinal Deformity Surgeries?: A Meta-analysis.

A meta-analysis study. This meta-analysis evaluates the difference in surgical outcomes between obese and nonobese patients undergoing adult spinal deformity (ASD) corrective surgery. ASD encompasses a wide range of debilitating spinal abnormalities. Concurrently, obesity is on the rise globally and has been shown to influence the outcomes of ASD management. The relationship between obesity and surgical outcomes in ASD has been the focus of recent studies, yielding various results. We conducted a comprehensive search of PubMed, Cochrane, and Google Scholar (pages 1-20) through June of 2024. The surgical outcomes assessed included postoperative complications, revision rates, wound infections, thromboembolic events, implant-related complications, and nonhome discharge. Surgical parameters such as operative time, length of stay (LOS), and estimated blood loss (EBL), as well as functional outcomes like the Oswestry Disability Index (ODI) and pain scores were analyzed. Nine studies met the inclusion criteria. Nonobese patients exhibited a lower rate of implant-related complications [odds ratio (OR)=0.25; 95% CI: 0.12-0.52, P =0.0002] and nonhome discharge (OR=0.52; 95% CI: 0.32-0.84, P =0.007). In addition, nonobese patients had reduced LOS (MD=-0.29; 95% CI: -0.53 to -0.05, P =0.02) and EBL (SMD=-0.68; 95% CI: -1.19 to -0.18, P =0.008). No statistically significant differences were observed for the remaining outcomes. Nonobese patients undergoing ASD corrective surgery are associated with fewer implant-related complications, a lower EBL, shorter LOS, and a higher likelihood of being discharged home compared with their obese counterparts.

Machine learning applications in adult spinal deformity corrective surgery: a narrative review

Machine learning applications in adult spinal deformity corrective surgery: a narrative review

Machine Learning Applications in Adult Spinal Deformity Corrective Surgery: A Narrative Review

Machine Learning Applications in Adult Spinal Deformity Corrective Surgery: A Narrative Review

P132. Alignment schematic impact on complications and outcomes in adult spinal deformity corrective surgery

P132. Alignment schematic impact on complications and outcomes in adult spinal deformity corrective surgery

P176. Waiting on a response: a full-body analysis of patients maintaining pelvic compensation following adult spinal deformity corrective surgery

P176. Waiting on a response: a full-body analysis of patients maintaining pelvic compensation following adult spinal deformity corrective surgery

P149. Optimal octogenarians: which elderly patients best tolerate adult spinal deformity corrective surgery?

P149. Optimal octogenarians: which elderly patients best tolerate adult spinal deformity corrective surgery?

Durability of substantial clinical benefit leading to optimal outcomes in adult spinal deformity corrective surgery: a minimum 5-year analysis.

The objective was to evaluate factors associated with the long-term durability of outcomes in adult spinal deformity (ASD) patients. Operative ASD patients fused from at least L1 to the sacrum with baseline (BL) to 5-year (5Y) follow-up were included. Substantial clinical benefit (SCB) in Oswestry Disability Index (ODI), numeric rating scale (NRS)-back, NRS-leg, and Scoliosis Research Society (SRS)-22r scores and physical component score were assessed on the basis of previously published values. Factors were evaluated on the basis of meeting optimal outcomes (OO) at 2 years (2+) and 5 years (5+). Furthermore, 2+ patients were isolated and evaluated on the basis of meeting OO at 5 years (2+5+) or not at 5 years (2+5-). OO were defined as follows: no reoperation, major mechanical failure, proximal junctional failure, and meeting either 1) SCB in terms of ODI score (decrease > 18.8) or 2) ODI < 15 and SRS-22r total > 4.5. In total, 330 ASD patients met the inclusion criteria, with 45.5% meeting SCB for ODI at 2 years, while 46.0% met SCB at 5 years; 79% of those who achieved 2-year (2Y) SCB went on to achieve 5Y SCB. This rate was lower for OO, with 41% achieving 2Y OO (2+), while 37% met 5Y OO (5+) and 80% of 2+ patients had durable outcomes until 5+ (32% of the total cohort). Of the patient factors, frailty was significantly different among groups at 2 years, while comorbidity burden was significantly different at 5 years and the combination thereof differed in those with durable outcomes. Those who regained their level of activity postoperatively had 4 times higher odds of maintaining OO from 2 years to 5 years (p < 0.05). Osteoporosis rates, although equivocal at BL, were higher at the last follow-up in those who met 2Y OO but failed to meet 5Y OO. The odds of achieving OO at 5 years in 2+ patients decreased by 47% for each additional comorbidity and decreased by 74% in those who had lower-extremity paresthesias at BL (both p < 0.05). Controlling for patient factors and BL disability found fewer levels fused, decreased correction of sagittal vertical axis, and increased correction of pelvic incidence-lumbar lordosis mismatch to be predictive of maintaining 2Y OO until 5 years (p < 0.05). SCB was met in 46% of ASD patients at 5 years. The durability of OO was seen in a third of patients until 5 years postoperatively. Higher rates of medical complications were seen in those who failed to achieve and maintain OO until 5 years. Frailty and comorbidity burden were significant factors associated with the achievement and durability of OO until 5 years.

The Incremental Clinical Benefit of Adding Layers of Complexity to the Planning and Execution of Adult Spinal Deformity Corrective Surgery.

For patients with surgical adult spinal deformity (ASD), our understanding of alignment has evolved, especially in the last 20 years. Determination of optimal restoration of alignment and spinal shape has been increasingly studied, yet the assessment of how these alignment schematics have incrementally added benefit to outcomes remains to be evaluated. Patients with ASD with baseline and 2-year were included, classified by 4 alignment measures: Scoliosis Research Society (SRS)-Schwab, Age-Adjusted, Roussouly, and Global Alignment and Proportion (GAP). The incremental benefits of alignment schemas were assessed in chronological order as our understanding of optimal alignment progressed. Alignment was considered improved from baseline based on SRS-Schwab 0 or decrease in severity, Age-Adjusted ideal match, Roussouly current (based on sacral slope) matching theoretical (pelvic incidence-based), and decrease in proportion. Patients separated into 4 first improving in SRS-Schwab at 2-year, second Schwab improvement and matching Age-Adjusted, third two prior with Roussouly, and fourth improvement in all four. Comparison was accomplished with means comparison tests and χ 2 analyses. Sevenhundredthirty-two. patients met inclusion. SRS-Schwab BL: pelvic incidence-lumbar lordosis mismatch (++:32.9%), sagittal vertical axis (++: 23%), pelvic tilt (++:24.6%). 640 (87.4%) met criteria for first, 517 (70.6%) second, 176 (24%) third, and 55 (7.5%) fourth. The addition of Roussouly (third) resulted in lower rates of mechanical complications and proximal junctional kyphosis (48.3%) and higher rates of meeting minimal clinically important difference (MCID) for physical component summary and SRS-Mental ( P < .05) compared with the second. Fourth compared with the third had higher rates of MCID for ODI (44.2% vs third: 28.3%, P = .011) and SRS-Appearance (70.6% vs 44.8%, P < .001). Mechanical complications and proximal junctional kyphosis were lower with the addition of Roussouly ( P = .024), while the addition of GAP had higher rates of meeting MCID for SRS-22 Appearance ( P = .002) and Oswestry Disability Index ( P = .085). Our evaluation of the incremental benefit that alignment schemas have provided in ASD corrective surgery suggests that the addition of Roussouly provided the greatest reduction in mechanical complications, while the incorporation of GAP provided the most significant improvement in patient-reported outcomes.

Highest Achievable Outcomes for Adult Spinal Deformity Corrective Surgery: Does Frailty Severity Exert a Ceiling Effect?

Retrospective single-center study. To assess the influence of frailty on optimal outcome following ASD corrective surgery. Frailty is a determining factor in outcomes after ASD surgery and may exert a ceiling effect on the best possible outcome. ASD patients with frailty measures, baseline, and 2-year ODI included. Frailty was classified as Not Frail (NF), Frail (F) and Severely Frail (SF) based on the modified Frailty Index, then stratified into quartiles based on two-year ODI improvement (most improved designated "Highest"). Logistic regression analyzed relationships between frailty and ODI score and improvement, maintenance, or deterioration. A Kaplan-Meier survival curve was used to analyze differences in time to complication or reoperation. A total of 393 ASD patients were isolated (55.2% NF, 31.0% F, and 13.7% SF), then classified as 12.5% NF-Highest, 17.8% F-Highest, and 3.1% SF-Highest. The SF group had the highest rate of deterioration (16.7%, P =0.025) in the second postoperative year, but the groups were similar in improvement (NF: 10.1%, F: 11.5%, SF: 9.3%, P =0.886). Improvement of SF patients was greatest at six months (ΔODI of -22.6±18.0, P <0.001), but NF and F patients reached maximal ODI at 2 years (ΔODI of -15.7±17.9 and -20.5±18.4, respectively). SF patients initially showed the greatest improvement in ODI (NF: -4.8±19.0, F: -12.4±19.3, SF: -22.6±18.0 at six months, P <0.001). A Kaplan-Meier survival curve showed a trend of less time to major complication or reoperation by 2 years with increasing frailty (NF: 7.5±0.381 yr, F: 6.7±0.511 yr, SF: 5.8±0.757 yr; P =0.113). Increasing frailty had a negative effect on maximal improvement, where severely frail patients exhibited a parabolic effect with greater initial improvement due to higher baseline disability, but reached a ceiling effect with less overall maximal improvement. Severe frailty may exert a ceiling effect on improvement and impair maintenance of improvement following surgery. Level III.

326 Factors Associated With the Maintenance of Cost-Effectiveness at 5 Years in Adult Spinal Deformity Corrective Surgery

INTRODUCTION: Substantial increase of costs in the surgical treatment of adult spinal deformity has given precedence to scrutinize the value it can provide hence cost-effectiveness (CE) is a vital analytical constituent. The analysis of factors associated with the durability of cost-effectiveness at 5 years has not been previously evaluated. METHODS: Adult spinal deformity (ASD) patients with baseline (BL) to 5-year (5Y) data were included. Cost calculation using PearlDiver database and CMS.gov definitions was used. Cost analysis was based on average DRG reimbursement rates. ODI was converted to SF-6D, with a 3% discount applied for residual decline in life expectancy. Cost per QALY gained at 2Y and 5Y was calculated. Threshold value for cost per QALY was $100,000. Patients that met 2Y (CE2+) were grouped based on meeting CE at 5Y(CE5+) or not(CE5-). Analysis based on meeting cost-effectiveness (CE) at 2Y and 5Y was conducted. Conditional-inference-tree (CIT) established cutoffs values for HRQLs. RESULTS: 299 patients with 5Y data were included. Major and minor complication rates were 11% and 47% respectively, while 26% underwent reoperation by 5Y. The mean cost of surgery was $91,095 ± $47,003, utility-gain of 0.091 ± 0.086, and QALY of 0.171 ± 0.183, CE of $118,976 ± $208,323. 85.5% of the cohort met CE at 2Y, 79.2% at 5Y, whereas 59.6% met both. Frailty was comparable at baseline but was worse in CE5- at 2Y. CIT depicted 2Y ODI &lt; 18 and SRS-22r &gt; 3.3 (both p &lt; 0.03) being associated with higher rates of C5+. Multivariable-regression depicted higher baseline CCI and pelvic tilt (PT) to be the strongest baseline predictors of not maintaining CE at 5Y (CCI OR: 1.821, p = 0.009) (PT OR: 1.079, p = .030). CONCLUSIONS: The majority that met cost-effectiveness at the 2 year went on to maintain it at 5 years. Lower baseline CCI and PT were strong predictive factors.

168 Sustenance of Substantial Clinical Benefit in Adult Spinal Deformity Corrective Surgery Patients: A Minimum 5-Year Outcomes Analysis

INTRODUCTION: Clinical outcomes for adult spinal deformity patients has been extensively reported on, however factors associated with sustaining two year (2Y) substantial clinical benefit (SCB) till five year (5Y) remains unclear. METHODS: ASD patients fused from at least L1 to sacrum with 5Y postoperative data were included. Good Outcome(GO) was defined as: no reoperation, mechanical failure, proximal junctional failure(PJF) based on Lafage criteria, and [meeting either: (1) SCB for Oswestry Disability Index(ODI)(decrease of &gt;18.8), or (2) ODI &lt;15 and Scoliosis Research Society(SRS-22r) Total&gt;4.5]. Multivariable analysis controlled for age, BMI, CCI, frailty, deformity, HRQLs, and surgical variations. RESULTS: 330 ASD patients were included. 42% achieved GO at 2Y(2+) while 47% at 5Y(5+) did. 71% of 2+ cohort attained 5+. In 2- cohort, 29% achieved 5+. Isolating 2+ cohort, assessing 5+ vs 5-: 5- had greater SVA deformity at 5Y (p &lt; .05). Regaining the level of activity postoperatively was associated with 4x higher odds of maintaining GO from 2Y to 5Y (p &lt; .05). The odds of achieving GO at 5Y in 2+ decreased by 47% for each additional comorbidity and decreased by 74% in those that had lower extremity paresthesias at BL (both p &lt; .05). Decreased number of levels fused, decreased correction in SVA and increased correction in PI-LL to be predictive of sustaining 2Y GO till 5Y (all p &lt; 0.05). CONCLUSIONS: Overall, 47% had substantial clinical benefit till 5Y. While 71% of patients at 2Y sustained good clinical outcome till 5Y, major contributors to its loss were adjacent segment changes and rod fracture. The odds of achieving SCB till 5Y decreased by nearly 50% for each additional comorbidity. Decreased levels fused along with decreased correction of SVA and increased correction in PI-LL were predictive of optimal sustaining of clinical outcomes.

1073 Prone Transpsoas (PTP)-LLIF Approach Versus Standard LLIF in Patients Undergoing Surgical Revision Following Adult Spinal Deformity Correction Surgery

INTRODUCTION: Both the prone transpsoas (PTP) and standard LLIF have been developed to facilitate minimally invasive (MIS) indirect decompression, alignment correction, and posterior instrumentation. METHODS: A multi-center cohort of all patients was identified and all relevant data were retrospectively collected. Preoperative standing 36” scoliosis radiographs were retrospectively reviewed for pelvic incidence (PI), lumbar lordosis (LL), and PI minus LL (PI-LL mismatch). Postoperative regional sagittal alignment parameters were measured using the first postoperative standing 36” scoliosis radiographs. Finally, multivariable analysis was performed to assess the primary outcome measure: postoperative change in regional sagittal alignment (PI-LL mismatch). RESULTS: Two-hundred and two (n = 202) patients were retrospectively identified and included for formal analysis. One-hundred and fifty one (n = 151, 74.8%) of the patients underwent PTP revision while 51 (25.2%) underwent standard LLIF revision. Univariate analysis demonstrated a greater value for baseline mean pre-operative PI-LL mismatch in the PTP versus standard LLIF cohort (21.4 vs. 10.45°; p = 0.0001). Furthermore, multiple linear regression demonstrated that the PTP approach enabled significantly greater PI-LL mismatch change (p = 0.0017) and that this change was associated with the number of levels fused (p = 0.0481) as well as percutaneous (vs. open) screw placement (p = 0.0193). Finally, multiple logistic regression identified standard LLIF (p = 0.0378), female sex (p &lt; 0.0001), non-osteoporotic bone density (p &lt; 0.0001), and younger age (p &lt; 0.0001) as predictive of postoperative PI-LL mismatch &lt; 10° (the threshold under which such mismatch is no longer regarded as clinically significant deformity). CONCLUSIONS: Ultimately, PTP-LLIF was associated with greater net improvement in postoperative PI-LL mismatch, the primary outcome measure of this study. The present retrospective analysis therefore corroborated results of previous studies in suggesting that the utility of PTP-LLIF is translatable to ASD revision surgery.

Causes of Intraoperative Neuromonitoring Events in Adult Spine Deformity Surgery: A Systematic Review.

Systematic review. Intraoperative neuromonitoring (IOMN) has become a standard practice in the detection and prevention of nerve damage and postoperative deficit. While multicenter studies have addressed this inquiry, there have been no systematic reviews to date. This systematic review identifies the leading causes of IONM alerts during adult spinal deformity (ASD) surgeries. Following PRISMA guidelines, a literature search was performed in PubMed and Embase. IONM alert causes were grouped by equivalent terms used across different studies and binned into larger categories, including surgical maneuver, Changes in blood pressure/temperature, Oxygenation, Anesthesia, Patient position, and Unknown. Inclusion criteria were studies on adult patients receiving ASD correction surgery using IONM with documented alert causes. 1544 references were included in abstract review, 128 in full text review, and 16 studies qualified for data extraction. From those studies, there was a total of 3945 adult patients with 299 IONM alerts. Surgical maneuver led the alert causes (258 alerts/86.3%), with signal loss most commonly occurring at correction or osteotomy (101/33.8% and 95/31.8% respectively). Pedicle screw placement caused 35 alerts (11.7%). Changes in temperature and blood pressure were the third largest category (34/11.4%). The most frequent causes of IONM alerts in ASD surgery were surgical maneuvers such as correction, osteotomy, and pedicle screw placement. This information provides spine surgeons with a quantitative perspective on the causes of IONM changes and show that most occur at predictable times during ASD surgery.

Factors Associated With the Maintenance of Cost-effectiveness at Five Years in Adult Spinal Deformity Corrective Surgery.

Retrospective cohort. To evaluate factors associated with the long-term durability of cost-effectiveness (CE) in ASD patients. A substantial increase in costs associated with the surgical treatment for adult spinal deformity (ASD) has given precedence to scrutinize the value and utility it provides. We included 327 operative ASD patients with five-year (5yr) follow-up. Published methods were used to determine costs based on CMS.gov definitions and were based on the average DRG reimbursement rates. The utility was calculated using quality-adjusted life-years (QALY) utilizing the Oswestry Disability Index (ODI) converted to Short-Form Six-Dimension (SF-6D), with a 3% discount applied for its decline in life expectancy. The CE threshold of $150,000 was used for primary analysis. Major and minor complication rates were 11% and 47%, respectively, with 26% undergoing reoperation by five years. The mean cost associated with surgery was $91,095±$47,003, with a utility gain of 0.091±0.086 at one years, QALY gained at 2 years of 0.171±0.183, and at five years of 0.42±0.43. The cost per QALY at two years was $414,885, which decreased to $142,058 at five years.With the threshold of $150,000 for CE, 19% met CE at two years and 56% at five years. In those in which revision was avoided, 87% met cumulative CE till life expectancy. Controlling analysis depicted higher baseline CCI and pelvic tilt (PT) to be the strongest predictors for not maintaining durable CE to five years [CCI OR: 1.821 (1.159-2.862), P =0.009] [PT OR: 1.079 (1.007-1.155), P =0.030]. Most patients achieved cost-effectiveness after four years postoperatively, with 56% meeting at five years postoperatively. When revision was avoided, 87% of patients met cumulative cost-effectiveness till life expectancy. Mechanical complications were predictive of failure to achieve cost-effectiveness at two years, while comorbidity burden and medical complications were at five years.

Decisional regret following corrective adult spinal deformity surgery: a single institution study of incidence and risk factors.

To assess the characteristics and risk factors for decisional regret following corrective adult spinal deformity (ASD) surgery at our hospital. This is a retrospective cohort study of a single-surgeon ASD database. Adult patients (> 40years) who underwent ASD surgery from May 2016 to December 2020 with minimum 2-year follow-up were included (posterior-only, ≥ 4 levels fused to the pelvis) (n = 120). Ottawa decision regret questionnaires, a validated and reliable 5-item Likert scale, were sent to patients postoperatively. Regret scores were defined as (1) low regret: 0-39 (2) medium to high regret: 40-100. Risk factors for medium or high decisional regret were identified using multivariate models. Ninety patients were successfully contacted and 77 patients consented to participate. Nonparticipants were older, had a higher incidence of anxiety, and higher ASA class. There were 7 patients that reported medium or high decisional regret (9%). Ninety percentage of patients believed that surgery was the right decision, 86% believed that surgery was a wise choice, and 87% would do it again. 8% of patients regretted the surgery and 14% believed that surgery did them harm. 88% of patients felt better after surgery. On multivariate analysis, revision fusion surgery was independently associated with an increased risk of medium or high decisional regret (adjusted odds ratio: 6.000, 95% confidence interval: 1.074-33.534, p = 0.041). At our institution, we found a 9% incidence of decisional regret. Revision fusion was associated with increased decisional regret. Estimates for decisional regret should be based on single-institution experiences given differences in patient populations.

Should realignment goals vary based on patient frailty status in adult spinal deformity?

The objective of this study was to adjust the sagittal age-adjusted score (SAAS) to accommodate frailty in alignment considerations and thereby increase the predictability of clinical outcomes and junctional failure. Surgical adult spinal deformity (ASD) patients with 2-year data were included. Frailty was assessed with the continuous ASD modified frailty index (ASD-mFI). Two-year outcomes were proximal junctional kyphosis (PJK), proximal junctional failure (PJF), major mechanical complications, and best clinical outcome (BCO), defined as Oswestry Disability Index (ODI) score < 15 and Scoliosis Research Society outcomes questionnaire total score > 4.5 by 2 years. Linear regression analysis established a 6-week score based on the component scores of SAAS, frailty, and US normal values for ODI score. Logistic regression analysis followed by conditional inference tree run forest analysis generated categorical thresholds. Multivariate analysis, controlling for age, baseline deformity, and history of revision, was used to compare outcome rates, and logistic regression generated odds ratios for the continuous score. Thirty percent of the cohort was used as a random sample for internal validation. In total, 412 patients were included (mean ± SD age 60.1 ± 14.2 years, 80% female, BMI 26.9 ± 5.4 kg/m2). Baseline frailty categories were as follows: 57% not frail, 30% frail, and 14% severely frail. Overall, by 2 years, 39% of patients had developed PJK, 8% PJF, and 21% mechanical complications; 22% had undergone a reoperation; and 15% met BCO. When the cohort as a whole was assessed, the 6-week SAAS had a correlation with the development of PJK and PJF, but not mechanical complications, reoperation, or BCO. Development of mechanical complications, PJF, reoperation, and BCO demonstrated correlations with ASD-mFI (all p < 0.05). Regression analysis modifying SAAS on the basis of ODI norms and frailty generated the following equation: frailty-adjusted SAAS (FAS) = 0.108 × T1 pelvic angle + 0.162 × pelvic tilt - 0.39 × pelvic incidence - lumbar lordosis - 0.03 × ASD-mFI - 1.6771. With conditional inference tree analysis, thresholds were derived for FAS: aligned < 1.7, offset 1.7-2.2, and severely offset > 2.2. Significance between FAS categories was found for PJK, PJF, mechanical complications, reoperation, and BCO by 2 years. Binary logistic regression, controlling for baseline deformity and revision status, demonstrated significance between FAS and all 5 outcome variables (all p < 0.01). Internal validation saw each outcome variable maintain significance between categories, with even greater odds for PJF (OR 13.4, 95% CI 4.7-38.3, p < 0.001). Consideration of physiological age, in addition to chronological age, may be beneficial in the management of operative goals to maximize clinical outcomes while minimizing junctional failure. This combination enables the spine surgeon to fortify a surgical plan for even the most challenging patients undergoing ASD corrective surgery.

Achievement and Maintenance of Optimal Alignment After Adult Spinal Deformity Corrective Surgery: A 5-Year Outcome Analysis

We sought to assess factors contributing to optimal radiographic outcomes. Operative adult spinal deformity (ASD) patients with baseline and 5-year (5Y) data were included. Optimal alignment (O) was defined as improving in at least 1 Scoliosis Research Society-Schwab modifier without worsening in any Scoliosis Research Society-Schwab modifier. A robust outcome was defined as having optimal alignment 2 years (2Y) post operation that was maintained at 5Y. Predictors of robust outcomes were identified using multivariate regression analysis, with a conditional inference tree for continuous variables. Two-hundred and ninety-seven ASD patients met inclusion criteria. Most patients (77.4%) met O at 6W, which decreased to 54.2% at 2Y. The majority of patients (89.4%) that met O at 2Y went on to meet radiographic durability at 5Y (48.5% of total cohort). Rates of junctional failure were higher in O2+5- compared with O2+5- (P= 0.013), with reoperation rates of 17.2% due to loss of alignment. Multivariable regression identified the following independent predictors of optimal alignment at 5Y in those that had O at 2Y: inadequate correction of pelvic tilt and overcorrection of the difference between pelvic incidence and lumbar lordosis (P < 0.05). Increased age, body mass index, and invasiveness were the most significant nonradiographic predictors for not achieving 5Y durability (P < 0.05). The durability of optimal alignment after ASD corrective surgery was seen in about half of the patients at 5Y. While the majority of patients at 2Y maintained their radiographic outcomes at 5Y, major contributors to loss of alignment included junctional failure and adjacent region compensation, with only a minority of patients losing correction through the existing construct. The reoperation rate for loss of alignment was 17.2%. Loss of alignment requiring reoperation had a detrimental effect on 5Y clinical outcomes.