ClinicalTrials.gg
Sign In
RecruitingNCT04194138CADSUpdated Feb 17, 2026

Complex Adult Deformity Surgery (CADS)

An observational study in Adult Spinal Deformity, Scoliosis and Kyphosis, sponsored by International Spine Study Group Foundation. Recruiting at 18 sites in 2 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-02-17.

Sponsored by International Spine Study Group Foundation · Observational

From the registry’s dates

  • Started Jul 2018; still recruiting 8 years 3 months later.
Study type
Observational
Model
Cohort
Time perspective
Prospective
Enrollment
1,500
Ages
18 Years and older
Sex
All
01

Study summary

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.

Read the detailed description

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
02

Conditions studied

  • Adult Spinal Deformity
  • Scoliosis
  • Kyphosis
  • Sagittal Imbalance

Browse trials for

Keywords

  • Scoliosis
  • Kyphosis
  • Sagittal Imbalance
  • Spinal deformity
03

In context

Scoliosis

660 studies on the registry are indexed under Scoliosis; 186 are open to participants now.

This study's planned enrollment of 1,500 is above the median of 84 across 256 observational studies indexed under Scoliosis.

Browse Scoliosis studies →

Lead sponsor

International Spine Study Group Foundation is the lead sponsor of 7 studies on the registry; 4 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years and older
Sexes eligible
All
Accepts healthy volunteers
No
Sampling method
Non-probability sample

Study population

Multi-center, prospective, non-randomized analysis of surgically treated complex adult spinal deformity (ASD) patients.

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Criteria:

Inclusion criteria

Inclusion Criteria:

  1. Diagnosis of adult congenital, degenerative, idiopathic or iatrogenic spinal deformity
  2. Full body EOS radiographic assessment (sagittal and coronal visualization from skull to foot)

  3. Complex patients are defined as and meeting any one of the subsequent criteria:

    1. Radiographic criteria:

      • PI-LL ≥ 25 degrees
      • TPA ≥ 30 degrees
      • SVA>15cm
      • Thoracic scoliosis ≥ 70 degrees
      • Thoracolumbar/lumbar scoliosis ≥ 50 degrees
      • Global coronal malalignment >7cm

    2. Procedural criteria:

      • Posterior spinal fusion > 12 levels
      • 3 column osteotomy or ACR

    3. Geriatric criteria:

      • Age >65 years and minimum 7 levels of spinal instrumentation during surgery

Exclusion criteria

Exclusion Criteria:

  1. Age \<18 years of age
  2. Active spine tumor or infection
  3. Deformity due to acute trauma
  4. Neuromuscular conditions/diseases (Parkinson's, Multiple Sclerosis, Post-polio syndrome)
  5. Syndromic scoliosis
  6. Inflammatory arthritis/auto immune diseases (Rheumatoid arthritis, Lupus, Ankylosing Spondylitis)
  7. Prisoners
  8. Women who are pregnant
  9. Non English speaking patients
05

Study design

Observational model
Cohort
Time perspective
Prospective
Enrollment
1,500 participants (estimated)
Target follow-up
10 Years
Patient registry
Yes

Groups and cohorts

  • Operative

    A. Multicenter, prospective, nonrandomized analysis of operatively treated complex ASD patients meeting the following Inclusion Criteria 1. 18 years of age or greater at the time of treatment 2. Diagnosis of adult congenital, degenerative, idiopathic or iatrogenic spinal deformity 3. Full body EOS radiographic assessment (sagittal and coronal visualization from skull to foot) 4. Complex patients are defined as and meeting any one of the subsequent criteria: a. Radiographic criteria: i. PI-LL ≥ 25 degrees ii. TPA ≥ 30 degrees iii. SVA\>15cm iv. Thoracic scoliosis ≥ 70 degrees v. Thoracolumbar/lumbar scoliosis ≥ 50 degrees vi. Global coronal malalignment \>7cm b. Procedural criteria: i. Posterior spinal fusion \> 12 levels ii. 3 column osteotomy or ACR c. Geriatric criteria: i. Age \>65 years and minimum 7 levels of spinal instrumentation during surgery

    Procedure: Index or spine revision surgery for complex adult spinal deformity

Interventions

  • ProcedureIndex or spine revision surgery for complex adult spinal deformity

    Surgical interventions will be patient specified by treating surgeon.

06

What researchers measure

Primary outcomes

  1. Scoliosis Research Society (SRS) 22r

    Scoliosis specific patient reported outcome

    Time frame: Change from Preop to 3 months and 1, 2, 5 & 10 year follow-up

  2. Oswestry Disability Index (ODI)

    Spine specific patient reported outcome

    Time frame: Change from Preop to 3 months and 1, 2, 5 & 10 year follow-up

  3. Veterans RAND 12 Item Health Survey (VR-12)

    Patient reported outcome

    Time frame: Change from Preop to 3 months and 1, 2, 5 & 10 year follow-up

  4. Radiographic Evaluation

    Cobb angles, Coronal \& Sagittal balance, spinopelvic measures

    Time frame: Change from Preop to 3 months and 1, 2, 5 & 10 year follow-up

  5. Patient-Reported Outcome Measurement Information System (PROMIS) - Anxiety

    Computer adaptive PROs

    Time frame: Change from Preop to 3 months and 1, 2, 5 & 10 year follow-up

  6. Patient-Reported Outcome Measurement Information System (PROMIS) - Depression

    Computer adaptive PRO

    Time frame: Change from Preop to 3 months and 1, 2, 5 & 10 year follow-up

  7. Patient-Reported Outcome Measurement Information System (PROMIS) - Pain Interference

    Computer adaptive PRO

    Time frame: Change from Preop to 3 months and 1, 2, 5 & 10 year follow-up

  8. Patient-Reported Outcome Measurement Information System (PROMIS) - Physical Function

    Computer adaptive PRO

    Time frame: Change from Preop to 3 months and 1, 2, 5 & 10 year follow-up

  9. Patient-Reported Outcome Measurement Information System (PROMIS) - Social Role Satisfaction

    Computer adaptive PRO

    Time frame: Change from Preop to 3 months and 1, 2, 5 & 10 year follow-up

  10. Patient-Reported Outcome Measurement Information System (PROMIS) - Social Satisfaction (DSA)

    Computer adaptive PRO

    Time frame: Change from Preop to 3 months and 1, 2, 5 & 10 year follow-up

  11. Visual Analog Scale - Back Pain

    Self-reported back pain on scale of 0 (No pain) to 10 (severe pain)

    Time frame: Change from Preop to 3 months and 1, 2, 5 & 10 year follow-up

  12. Visual Analog Scale - Leg Pain

    Self-reported leg pain on scale of 0 (No pain) to 10 (severe pain)

    Time frame: Change from Preop to 3 months and 1, 2, 5 & 10 year follow-up

Secondary outcomes

  1. Edmonton Frail Scale

    Evaluate frailty on scale of 0 to 17 where higher scores mean more frail

    Time frame: Change from Preop to 3months and 1, 2, 5 & 10 year follow-up

  2. Canadian Study of Health and Aging (CSHA)

    Frailty scale of 1 to 8; higher scores mean more frail

    Time frame: Change from Preop to 3months and 1, 2, 5 & 10 year follow-up

  3. Adverse Events

    Occurrence of Adverse events meeting reporting criteria and their relationship to intervention throughout the study

    Time frame: 3 months and 1, 2, 5 & 10 year post treatment

07

Study locations

17 of 18 sites recruiting
08

References and documents

Publications

  • Boutros M, Assi A, Diebo BG, Prince G, Karam M, Daher M, Ames CP, Bess S, Daniels AH, Gupta MC, Hostin R, Kim HJ, Klineberg EO, Lenke LG, Nunley PD, Passias PG, Schwab FJ, Shaffrey CI, Smith JS, Lafage R, Lafage V; International Spine Study Group. A New Normative Zone for Acetabular Anteversion Positioning in ASD Patients. J Orthop Res. 2026 Mar;44(3):e70171. doi: 10.1002/jor.70171. PubMed 41761562 ↗
  • Passias PG, Tretiakov P, Onafowokan OO, Das A, Lafage R, Smith JS, Line BG, Nayak P, Diebo B, Daniels AH, Gum JL, Hamilton DK, Buell TJ, Soroceanu A, Scheer JK, Eastlack RK, Mullin JP, Schoenfeld AJ, Mundis GM, Hosogane N, Yagi M, Mummaneni PV, Chou D, Fu KM, Than KD, Anand N, Okonkwo DO, Wang MY, Klineberg E, Kebaish KM, Lewis S, Hostin R, Gupta M, Lenke L, Kim HJ, Ames CP, Shaffrey CI, Bess S, Schwab F, Lafage V, Burton D. When is staging complex adult spinal deformity advantageous? Identifying subsets of patients who benefit from staged interventions. J Neurosurg Spine. 2024 Nov 22;42(2):185-192. doi: 10.3171/2024.8.SPINE24365. Print 2025 Feb 1. PubMed 39576989 ↗

Individual participant data

Plan to share: No

09

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reachedSimilar studies: half by the dot; the band is the middle halfHalf of similar studies reached it by the dot; the band is the middle half, from a quarter to three quarters

Started Jul 2018 (actual). Primary completion is estimated for Dec 2028, 125 months after the start.

Of 94 non-industry observational studies under Scoliosis, half reached primary completion within 29 months of starting (the median), counting those still running; a quarter within 9 and three quarters within 99. This study's planned 125 months is above that.

Counting every sponsor, half of 106 studies reached it within 36 months; a quarter within 9 and three quarters within 92.

How these figures are worked out, and which studies are left out of them.

Registered
Nov 25, 2019
First posted
Dec 11, 2019
StartActual
Jul 30, 2018
Primary completionEst.
Dec 31, 2028
CompletionEst.
Jul 31, 2032
Last update
Feb 17, 2026
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on Feb 17, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT04194138
Lead sponsor
International Spine Study Group Foundation
Collaborators
Medtronic, Globus Medical Inc, SI-BONE, Inc.
Responsible party
Sponsor
First posted
Dec 11, 2019
Start date
Jul 30, 2018
Primary completion
Dec 31, 2028 (estimated)
Completion
Jul 31, 2032 (estimated)
Last update
Feb 17, 2026

Study contacts

Christine Baldus, MS
Contact
baldusc@wustl.edu
618-444-4130
Ray Pinteric
Contact
ray.pinteric@outlook.com
Shay Bess, MD
principal investigator
Lawrence Lenke, MD
principal investigator · Columbia University, Department of Orthopedic Surgery
Christopher Shaffrey, MD
principal investigator · Duke University, Departments of Neurosurgery and Orthopaedic Surgery

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Interested in this study?

Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.

Contact study team

Follow this study

Get an email when the registry record changes — status, dates, results — or when someone posts here.

Sign in to follow

Discussion

Questions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.

Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.

Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.

Other studies in this condition

Scoliosis →

Other studies from this sponsor

International Spine Study Group Foundation

Start the discussion