Proximal Junctional KyphosisMSKNCT04422288
MSK Validation Study
An observational study of Proximal Junctional Kyphosis and Spino-pelvic Alignment, run by NuVasive at 2 sites in United States.
Trial summary
Spinal posture and imbalance are known to be related to increased muscle expenditure, with narrow "cone of economy" of muscle effort defining the most comfortable postures. Therefore, it is hypothesized that predicting the posture of the lowest muscle effort available for a patient with a given spinal alignment and… Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Proximal Junctional Kyphosis, Spino-pelvic Alignment, Thoracolumbar Spinal Fusion
- How many people
- 200 participants
- Where
- 2 sitesUnited States
- Study dates
- 15 May 2020to 1 Oct 2022
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- Adult, Older adult
Study population: At least 186 patients will be enrolled in this multicenter combined observational / in silico study, recruited into 3 groups (at least 62 cases each) according to the number of levels instrumented: 1. local fusion, 1-2 segments; 2. short fusion, 3-4 segments; 3. long fusion, 5+ segments.
Who may be able to join
- Male or female patients
- Any ethnicity
- At least 18 years of age
- Has undergone a thoracolumbar spinal fusion procedure
Who cannot join
- Patient has had a prior spinal surgery in the thoracic and/or lumbar spine;
- Patient presents scoliosis greater or equal to 20° T4-T12 Cobb angle;
- Patient has been diagnosed with idiopathic adolescent scoliosis (treated or untreated);
- Patient has other implants that obstruct the spine and/or pelvis in the lateral view;
- Patient presents any of the following complications: pseudoarthrosis, instrumentation failure, instrumentation pull-out and/or requires a revision surgery at any time following the primary surgery and prior to 3 months post-op;
- Patient is a prisoner.
Trial locations and contacts
2 sites in 1 country.
United States2 sites
University of Colorado
Aurora, Colorado, 80045
Univerisity of Pittsburgh Medical Center
Pittsburgh, Pennsylvania, 15213
About this study
Official title: Prediction of Postoperative Global Sagittal Alignment Using Musculoskeletal Modeling - Validation Study
Spinal posture and imbalance are known to be related to increased muscle expenditure, with narrow "cone of economy" of muscle effort defining the most comfortable postures. Therefore, it is hypothesized that predicting the posture of the lowest muscle effort available for a patient with a given spinal alignment and body properties will correspond to the posture the patient will most likely assume. Based on established musculoskeletal models, a model application was configured to allow prediction of this optimal posture. This study aims to assess the validity of this approach and the value of using biomechanical modeling for pre-operative planning.
Read the detailed description
The objective of this study is to validate a novel method of post-operative posture prediction - a full-body biomechanical model based on an established technology and physiological reasoning. Specifically, the model ability to predict postoperative global sagittal alignment, including compensatory and reciprocal changes, from pre-operative radiographic imaging and the information about planned posture correction will be evaluated. This will be realized by comparing model-predicted radiographic measures and overall balance to follow-up patient radiographs.
Having demonstrated model validity to predict postoperative posture will allow to use this method for simulating various "what-if" scenarios to empower surgical planning by predicting expected outcomes. This can be used to optimizing preoperative planning, which has a potential to substantially improved surgery predictability and patient outcomes.
Furthermore, validated model will allow scientific investigation of the principles governing human posture and biomechanics of the pathological spine. Generated scientific knowledge of biomechanical factors influencing sagittal posture and surgery outcomes (e.g. number of levels fused, amount and distribution of posture correction, etc.) can lead to improvements in clinical management of spinal disorders.
What is being measured
The primary outcome is the main question the study is designed to answer.
Difference between model-predicted and observed postural measures - Thoracic Kyphosis (TK)
The simulation-predicted posture will be compared against the posture observed at follow-up, using the thoracic kyphosis (TK) angle.
Measured: 3 months
Difference between model-predicted and observed postural measures - Lumbar Lordosis (LL)
The simulation-predicted posture will be compared against the posture observed at follow-up, using the LL - lumbar lordosis (LL) angle.
Measured: 3 Months
Difference between model-predicted and observed postural measures - T1 Pelvic Angle (TPA)
The simulation-predicted posture will be compared against the posture observed at follow-up, using the T1 pelvic angle (TPA).
Measured: 3 Months
Difference between model-predicted and observed postural measures - Pelvic Incidence-Lumbar Lordosis Mismatch (∆PILL)
The simulation-predicted posture will be compared against the posture observed at follow-up, using the pelvic incidence-lumbar lordosis mismatch (∆PILL).
Measured: 3 Months
Secondary outcomes (1)
Model sensitivity and specificity in predicting posture imbalance
A McNemar's test (a paired Chi-squared test) will be used to test the null hypothesis that the balance prediction is due to chance, allowing to assess if the model predictive power is better than random.
Measured: 3 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted9 Jun 2020
- Study start15 May 2020
- Primary completion1 Oct 2022
- Study completion1 Oct 2022
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Proximal Junctional KyphosisStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Retrospective
- Enrolment
- 200 participants (actual)
Sponsor and investigators
- Lead sponsor
- NuVasive
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Kyle Malone, MS, Study director, NuVasive
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04422288
- Sponsor's protocol ID
- NUVA.MSK1901
- Acronym
- MSK
- Status last verified
- Dec 2025
- First submitted
- 2 Jun 2020
- Last updated
- 22 Dec 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 22 Dec 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Prediction of Postoperative Global Sagittal Alignment Using Musculoskeletal Modeling - Validation Study
- ClinicalTrials.gov ID
- NCT04422288
- Acronym / sponsor ID
- MSK / NUVA.MSK1901
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 200 participants (actual)
- Lead sponsor
- NuVasiveIndustry (pharma, biotech, devices)
- Study start
- 15 May 2020 (actual)
- Primary completion
- 1 Oct 2022 (actual)
- Study completion
- 1 Oct 2022 (actual)
- First posted
- 9 Jun 2020 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Spinal posture and imbalance are known to be related to increased muscle expenditure, with narrow "cone of economy" of muscle effort defining the most comfortable postures. Therefore, it is hypothesized that predicting the posture of the lowest muscle effort available for a patient with a given spinal alignment and body properties will correspond to the posture the patient will most likely assume. Based on established musculoskeletal models, a model application was configured to allow prediction of this optimal posture. This study aims to assess the validity of this approach and the value of using biomechanical modeling for pre-operative planning.
Detailed description
The objective of this study is to validate a novel method of post-operative posture prediction - a full-body biomechanical model based on an established technology and physiological reasoning. Specifically, the model ability to predict postoperative global sagittal alignment, including compensatory and reciprocal changes, from pre-operative radiographic imaging and the information about planned posture correction will be evaluated. This will be realized by comparing model-predicted radiographic measures and overall balance to follow-up patient radiographs.
Having demonstrated model validity to predict postoperative posture will allow to use this method for simulating various "what-if" scenarios to empower surgical planning by predicting expected outcomes. This can be used to optimizing preoperative planning, which has a potential to substantially improved surgery predictability and patient outcomes.
Furthermore, validated model will allow scientific investigation of the principles governing human posture and biomechanics of the pathological spine. Generated scientific knowledge of biomechanical factors influencing sagittal posture and surgery outcomes (e.g. number of levels fused, amount and distribution of posture correction, etc.) can lead to improvements in clinical management of spinal disorders.
Study design
- Observational model
- Cohort
- Time perspective
- Retrospective
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Age groups
- Adult, Older adult
- Study population
- At least 186 patients will be enrolled in this multicenter combined observational / in silico study, recruited into 3 groups (at least 62 cases each) according to the number of levels instrumented: 1. local fusion, 1-2 segments; 2. short fusion, 3-4 segments; 3. long fusion, 5+ segments.
Key inclusion criteria (4 listed)
- Male or female patients
- Any ethnicity
- At least 18 years of age
- Has undergone a thoracolumbar spinal fusion procedure
Key exclusion criteria (6 listed)
- Patient has had a prior spinal surgery in the thoracic and/or lumbar spine;
- Patient presents scoliosis greater or equal to 20° T4-T12 Cobb angle;
- Patient has been diagnosed with idiopathic adolescent scoliosis (treated or untreated);
- Patient has other implants that obstruct the spine and/or pelvis in the lateral view;
- Patient presents any of the following complications: pseudoarthrosis, instrumentation failure, instrumentation pull-out and/or requires a revision surgery at any time following the primary surgery and prior to 3 months post-op;
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Difference between model-predicted and observed postural measures - Thoracic Kyphosis (TK)
Time frame: 3 months
The simulation-predicted posture will be compared against the posture observed at follow-up, using the thoracic kyphosis (TK) angle.
Difference between model-predicted and observed postural measures - Lumbar Lordosis (LL)
Time frame: 3 Months
The simulation-predicted posture will be compared against the posture observed at follow-up, using the LL - lumbar lordosis (LL) angle.
Difference between model-predicted and observed postural measures - T1 Pelvic Angle (TPA)
Time frame: 3 Months
The simulation-predicted posture will be compared against the posture observed at follow-up, using the T1 pelvic angle (TPA).
Difference between model-predicted and observed postural measures - Pelvic Incidence-Lumbar Lordosis Mismatch (∆PILL)
Time frame: 3 Months
The simulation-predicted posture will be compared against the posture observed at follow-up, using the pelvic incidence-lumbar lordosis mismatch (∆PILL).
1 secondary outcome
Model sensitivity and specificity in predicting posture imbalance
Time frame: 3 months
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 22 Dec 2025.
Related trials for Proximal Junctional Kyphosis
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Efficacy of Sub-laminar and/or Interspinous Tethers to Prevent Proximal Junctional Kyphosis After Surgical Correction of Adult Spinal Deformity
Proximal Junctional Kyphosis
Not yet recruitingObservational study
Retrospective Evaluation of Upper Instrumented Vertebrae (UIV) Screw Loosening Following Spine Surgery
Thoracolumbar Spinal Fusion
RecruitingObservational study
Prospective, Multicenter, Case-Control Analysis of the VersaTie Posterior Fixation System to Prevent Proximal Junctional Failure in Long Posterior Spinal Fusion Constructs for Adult Patients
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RecruitingPhase 4
Post-Operative Thoracolumosacral Orthosis for PJK
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Kyle Malone, MS study director
NuVasive
2 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Proximal Junctional Kyphosis and Spino-pelvic Alignment, run by NuVasive at 2 sites in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 22 Dec 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 2 sites in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Difference between model-predicted and observed postural measures - Thoracic Kyphosis (TK) (time frame: 3 months). The study lists 4 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 22 Dec 2025.