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Pedicle ScrewODYSSEENCT05565131

Performance Measurement and Safety Evaluation of the PYTHEAS® ODYSSEE Angular Assistance System for Intra-pedicular Screw Placement in Adult Spine Surgery

A study testing Guided placement with PYTHEAS® ODYSSEE in people with Pedicle Screw and Surgical Navigation Systems, run by Centre Hospitalier Universitaire de Nīmes at 2 sites in France.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
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Trial summary

Pedicle screw malposition is a common problem for spine surgeons. A poorly placed screw can lead to potentially serious complications (hemorrhage, paralysis) in the short- or medium-term. Accurate images during surgery facilitates preoperative planning and aids the placement of pedicle screws. Read more about this study

Who is it for?
Ages 18 years and older
Conditions the study is for
Pedicle Screw, Surgical Navigation Systems
What is being tested?
Guided placement with PYTHEAS® ODYSSEE
Type of treatment
Medical device
Could I receive a placebo?
No, everyone receives an active treatment
How many people
14 participants
Where
2 sitesFrance
Study dates
23 Sep 2022to 14 Mar 2023
Phase
Interventional
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
  • No healthy volunteers
  • Adult, Older adult

Who may be able to join

  • Patient with indication for posterior arthrodesis of at least 2 lumbar or thoracic vertebrae with placement of pedicle screws at vertebral level for :
  • Traumatology: fracture with significant vertebral compression or major kyphosis deformity, ligament and/or disc injury resulting in instability, with the need to free the marrow or nerve roots, OR
  • Deformity: idiopathic scoliosis with surgical indication for increased curvature, thoracic curvature greater than 45° or lumbar curvature greater than 35°, OR
  • Revision surgery for extension of the assembly in the presence of a possible adjacent syndrome responsible for instability and/or central or foraminal stenosis, OR
  • Degenerative: symptomatic spondylolisthesis, degenerative scoliotic deformity, narrow lumbar canal with canal release leading to instability, syndrome adjacent to a previously performed montage.
  • The patient must have given their free and informed consent and signed the consent form
  • The patient must be a member or beneficiary of a health insurance plan

Who cannot join

  • Patients with contraindication to screw placement
  • Patients with contraindication to CT scan
  • Silicon allergy
  • The subject is participating in a category 1 interventional study, or is in a period of exclusion determined by a previous study
  • The patient is unable to express their consent
  • It is impossible to give the subject informed information
  • The patient is under safeguard of justice or state guardianship
  • Pregnant, parturient or breastfeeding

Trial locations and contacts

2 sites in 1 country.

France2 sites
  • Hôpital Saint Joseph

    Marseille

  • CHU de Nimes

    Nîmes

Other trials in France

About this study

Official title: Performance Measurement and Safety Evaluation of the PYTHEAS® ODYSSEE Angular Assistance System for Intra-pedicular Screw Placement in Adult Spine Surgery. First-in-human Study

Pedicle screw malposition is a common problem for spine surgeons. A poorly placed screw can lead to potentially serious complications (hemorrhage, paralysis) in the short- or medium-term. Accurate images during surgery facilitates preoperative planning and aids the placement of pedicle screws.

Surgical navigation covers all techniques and equipment (hardware and software) needed to perform a computer-assisted procedure with 3D image visualization of the surgical act.

Read more

Surgical navigation systems have been on the market for about 15 years. Surgical navigation increases the accuracy of pedicle screw placement. Many technologies are available, but they are expensive and often require extensive instrumentation.

The PYTHEAS® ODYSSEE angular assistance system has many advantages over more widely used systems. Indeed, this system provides surgeons with the necessary information to correctly insert pedicle screws during posterior spondylodesis procedures for the treatment of deformity, osteoarthritis (degenerative spine) and trauma.

Compared to competing solutions, the purpose of this device is to reduce pedicle screw malpositioning while offering minimal radiation exposure and the least possible impact on the conventional surgical workflow. It is a lightweight, efficient and easy-to-use medical device with 2-step functionality: 1) Surgical planning of pedicle screws based on a preoperative scan; 2) Angular assistance tool during surgery.

The study investigators wish to evaluate the performance and safety of the PYTHEAS® ODYSSEE medical device (not CE marked) as well as its usability in a pilot study of first use in humans.

Without a navigation system, the literature reports that on average 9 to 10% of perforations are incorrectly positioned by the "free hand" method. With the PYTHEAS® ODYSSEE angular assistance device, the study hypothesis is that this rate will be 5%, i.e. a 50% improvement.

Being tested
Guided placement with PYTHEAS® ODYSSEE
Keywords
Spinal deformity

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • Guided placement with PYTHEAS® ODYSSEEDevice

    Pre-surgery, the surgeon generates a 3D model of the spine from a preoperative CT scan During the perforation and insertion of the implant, the system indicates the orientation of the pedicle path and the current orientation of the instruments (perforation tool) with the orientation sensor (inertial sensor). The system also displays the position of the entry point of the planned pedicle path on the views.

Study groups in NCT05565131
Study groupRoleWhat they receive
PAtients requiring pedicle screw implantationExperimentalNot described
Receives: Device: Guided placement with PYTHEAS® ODYSSEE

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Accuracy of the PYTHEAS® ODYSSEE angular assistance device for directing the pedicle

    Number of perforations with the correct direction/Total number of perforations performed. The correct direction will be determined using a palpator guide before screw placement, and considered satisfactory when the internal, external, superior and inferior walls of the intra-pedicular path are respected

    Measured: Day 0

Secondary outcomes (7)
  1. Correct screw positioning rate

    Number of correctly positioned screws (in trans-pedicular) / Number of screws placed. Correct placement determined by CT scan performed immediately postoperatively

    Measured: Day 0

  2. Adverse events

    No adverse events are anticipated directly linked to the device

    Measured: Day 0

  3. Operating time according to the calibration mode performed (specific mode/global mode)

    Operating time (minutes): time from incision until closing indicated on the management software.

    Measured: Day 0

  4. Surgeon's satisfaction with the calibration (specific/global)

    5-level Likert scale + one item with open-ended. The questions asked will be:

    • Are you satisfied with the specific calibration?
    • Are you satisfied with the overall calibration?
    • What type of calibration would you prefer to use in practice? In which cases?

    Measured: Day 0

  5. Surgeon's satisfaction with technical quality of the transfer between the PYTHEAS tablet and the computer for each procedure

    5-level Likert scale + one item with open-ended. The questions asked will be:

    • Are you satisfied with the transfer time between the tablet and the computer?
    • Are you satisfied with the ease of transfer between the tablet and the computer?

    Measured: Day 0

  6. Surgeon's satisfaction with tablet interaction

    5-level Likert scale + suggestions for improvement. The questions asked will be:

    • Are you satisfied with the responsiveness of the tablet?
    • Are you satisfied with the interactivity of the tablet?
    • Are you satisfied with the quality of the images displayed by the tablet?
    • Suggestions for improvement.

    Measured: Day 0

  7. Surgeon's reported overall usability of the PYTHEAS® ODYSSEE

    The System Usability Scale (SUS): a 10-item questionnaire where a score of 75 or more is generally considered "good", and 50 to 75 is considered "fair" or "adequate". A score below 50 indicates major problems in terms of satisfaction.

    Measured: Day 0

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted4 Oct 2022
  2. Study start23 Sep 2022
  3. Primary completion14 Mar 2023
  4. Study completion14 Mar 2023

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase N/A
Primary purpose
Other
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrolment
14 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT05565131
Sponsor's protocol ID
IDIL/2021/VH-01
Acronym
ODYSSEE
Status last verified
Sep 2022
First submitted
27 Sep 2022
Last updated
21 Apr 2026
Results posted
No
FDA-regulated drug
No
FDA-regulated device
No

Publications

  • Haignere V, Faure A, Giorgi H, Afonso D, Luquiens G, Kabani S, Chevallier T, Kouyoumdjian P. Performance and safety of the PYTHEAS Your Guided Trajectory(R) for intra-pedicular screw placement in spine surgery. J Orthop Surg Res. 2026 Apr 11;21(1):332. doi: 10.1186/s13018-026-06749-9.

    PubMed 41963965

Questions about this trial

What is this clinical trial studying?

A study testing Guided placement with PYTHEAS® ODYSSEE in people with Pedicle Screw and Surgical Navigation Systems, run by Centre Hospitalier Universitaire de Nīmes at 2 sites in France.

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 7 inclusion and 8 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 21 Apr 2026. 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 France. 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?

Accuracy of the PYTHEAS® ODYSSEE angular assistance device for directing the pedicle (time frame: Day 0). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT05565131, which also lists 1 linked publication.

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 21 Apr 2026.

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