Complex Adult Deformity Surgery (CADS)

Specific Aims:

• Evaluate surgical treatment outcomes and identify best practice guidelines for complex adult spinal deformity (ASD) patients, including radiographic and clinical outcomes, surgical and postoperative complications, risk factors for and revision surgery rates, and the role of standard work to improve patient outcomes and reduce surgical and postoperative complications.

a. Complex ASD patients will be defined based upon clinical, radiographic and/or procedural criteria identified in an analysis of the existing ISSG ASD database: i. Magnitude of coronal and/or sagittal spinal deformity ≥75th percentile of patients in the ISSG database.

ii. Clinical or Radiographic parameters that corresponded to patients in the ISSG database that had complications requiring revision spine surgery and/or patients that had hospital length of stay \>9 days.

iii. Procedures involving 3 column osteotomies and/or anterior column reconstruction (ACR) of the spine

* Develop and validate a standardized, universal complications classification system for spine surgery * Evaluate perioperative blood management approaches, transfusion requirements, including variance in thresholds for blood transfusion and associated complications for adult spinal deformity surgery * Assess impact of opioid use and pain management on patient cost, complications and outcomes * Evaluate optimal opioid and analgesic usage and protocols for standard work development * Evaluate clinical outcomes utilizing legacy patient reported outcome measures (PROMs) including modified Oswestry Disability Index (mODI), Scoliosis Research Society Questionnaire 22r (SRS-22r), Veterans RAND-12 (VR-12), and numeric pain rating scale (NRS) and compare the results of these legacy PROMs to outcomes scores as measured by the NIH Patient Reported Outcomes Measurement Information System (PROMIS) - PROMIS Anxiety, Depression, Pain Interference, Physical Function, and Social Satisfaction. Secondary aims for PROM research for this study include

1. Validation of the PROMIS tool for ASD 2. Establish a core set of PROMs for best practice guidelines for ASD 3. Evaluate patient reported outcome variance for ASD according to SRS-Schwab spine deformity type including variance in baseline PROM domains impacted and variance in improvement in PROM domains 4. Evaluate ASD outcomes compared to population norms and investigate/develop appropriate measures of clinically significant improvement * Evaluate clinical outcomes stratifying by patient chronological and physiological age * Evaluate measures to quantify patient physiological age including patient frailty for ASD and validate a frailty measurement system for ASD * Evaluate the role of functional tests in patient's baseline frailty assessment including hand manometer and Edmonton Frail Scale. See appendix, pages 17 \& 18 for details. * Evaluate the contribution of patient frailty to patient outcomes, cost of care, disability, and complications * Evaluate if patient frailty is a static measure or if frailty is a dynamic measure that can be improved through "pre-habilitation" and if the according associations with reductions in frailty correlate with reductions of cost, complications, and improvement in outcomes * Evaluate cost variance for ASD surgery according to patient, institution, and geographical region and evaluate the cost effectiveness of surgical intervention for ASD * Evaluate incidence of and risk factors for mental health (MH) compromise among ASD patients and establish best practice guidelines for assessing MH for ASD patients * Evaluate the association of MH with surgical complications, outcomes, hospital length of stay and cost for ASD surgery * Evaluate the association of social health surgical complications, outcomes, hospital length of stay and cost for ASD surgery and risk factors for routine (home) discharge vs. skilled nursing facility (SNF)/rehabilitation facility * Broaden the evaluation of the surgically treated ASD patient to maximize evaluation of the entirety of the episode of care to include steps that can be taken prior to surgery including "prehabilitation," pain management, and MH care to improve treatment outcomes, reduce cost, reduce hospital length of stay, reduce non-routing discharge and reduce early and late complications * Establish a core set of standard work guidelines to clinically and radiographically evaluate and treat ASD patients and evaluate the utility of standard work to improve outcomes for ASD and formulate best practice guidelines for surgical treatment of ASD * Develop predictive analytic algorithms to risk stratify for best/worst outcomes, complications, sentinel events, and economic loss for ASD surgery

• Edmonton Frail Scale [Time frame: Change from Preop to 3months and 1, 2, 5 & 10 year follow-up]
• Canadian Study of Health and Aging (CSHA) [Time frame: Change from Preop to 3months and 1, 2, 5 & 10 year follow-up]
• Adverse Events [Time frame: 3 months and 1, 2, 5 & 10 year post treatment]