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Preface

Preface. This presentation and pilot study was conducted for a customer to assess the in-vivo implant performance and the effect of the implantation on the adjacent segments over a follow-up time between 12 and 60 months post-op.

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Preface

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  1. Preface This presentation and pilot study was conducted for a customer to assess the in-vivo implant performance and the effect of the implantation on the adjacent segments over a follow-up time between 12 and 60 months post-op. The presentation summarizes a small study cohort of 10 patients and shows one sample analysis. In order to protect the customers’ privacy, several details and key findings were deleted. The goal of this blinded presentation is to demonstrate some of the capabilities of the FXA software and to give an example of a presentation as it was given to surgeons in order to show the scientific, data driven and evidence based company philosophy of this client. For a dedicated presentation of the FXA method, or if you have any further questions, please contact us: Frank Trautwein, ft@acesgmbh.de, orDr. Frank Heuer, frank.heuer@acesgmbh.de, +49 711 34238223 (Director R&D) ACES GmbH, Kanalstrasse 12/1, 73728 Esslingen, Germany

  2. Introduction • Q: What is “Functional X-Ray Analysis”? • A: A scientific software tool, based on radiographic images, to • Analyze spinal kinematics • Investigate patient pathologies and different treatment options • Evaluate and document safety and efficacyin clinical trials, studies and post-market surveillance

  3. Introduction • Q: How does it work? • Radiographic images are feed into the analysis software • Software detects and precisely measures relative motion • Rates instability, degeneration, Range of Motion (ROM), Center of Rotation (COR/ICR), Subsidence, Migration… • Generates report with relevant information and analysis confidence • Static measurements also available: Disc Height, Foraminal Height, Spinal Canal Cross Section, Cobb Angle…

  4. Introduction • Q: What is the difference to other methods, such as RSA? • The FXA software does not need any Tantalum or other markers • Lower x-ray exposure – works with standard flexion/extension images as they are routinely taken for diagnosis and follow/up • Software uses a unique, patent pending matching algorithm which does not rely on edge identification like some other research or commercial projects. The algorithm is operator-independent. • Advantage: Superior accuracy, built-in out-of-plane compensation and 100% reproducible measurements.

  5. Validation (Synthetic Images) Validation Example: Pre-defined rotation centers on synthetic images • Goal and Method : • Software shall locate Centers of Rotation (COR) • They should match the centers that were used to create the synthetic images • Difference between actual and measured location is recorded Actual COR

  6. Validation (Synthetic Images) • Variation of intersegmental angles on synthetic images: • CAD model with defined angular rotations and COR locations was generated • Synthetic Flexion and Extension images generated • Images were processed and analyzed by the FXA software exactly the same way as X-ray images • Measured results were compared with actual values L1-2 L2-3 0.1° 0.5° 1.0° 2.0° 3.0° 5.0° L3-4 L4-5

  7. Validation (Synthetic Images) Example Result: Deviation of the measuredCOR (center of rotation) from the actual COR location Note: Synthetic images are ideal for algorithms utilizing edge detection, but rather challenging for our algorithm ROM = 5.00° L5-L4

  8. Results (Synthetic Images) Mean values of the measured ROM Deviation of the measured COR from the actual COR location 30.7 mm ± 36.8 mm 1.6 mm ± 0.7 mm 0.9 mm ± 0.7 mm 0.6 mm ± 0.3 mm 0.3 mm ± 0.1 mm 0.2 mm ± 0.1 mm 0.10° ± 0.03° 0.50° ± 0.03° 1.00° ± 0.01° 2.00° ± 0.02° 3.00° ± 0.02° 5.00° ± 0.01°

  9. Results (Synthetic Images) • “Real World” accuracy depends alsoon image quality: • Clarity and Contrast • Visibility of object to be evaluated • Out-of plane deviation • In-Vitro experiments conducted to assess FXA accuracy on actual x-ray images. Biomech. Lab at the University of Münster

  10. Functional X-Ray Analysisof the sample Implant An analysis of 9 patients (12 months follow-up)1 patient (5 years follow-up) Frank Trautwein, Dr. Frank Heuer, ACES Ing.-GmbH

  11. FXA - Study of the Sample™ Implant 08-Jun-2010 Date of Evaluation: Version: Functional X-Ray Analysis (FXA) V.1.5 Parameters: Range of Motion (ROM) Center of Rotation (COR) Subjects: 10 Patients 12 Implants (2 Patients with 2 Implants) Time Points: Pre-OP Post-OP {0, 3, 6, 12} 2 additional index levels with 18, 36 and 60 months

  12. FXA - Study Summary

  13. FXA - Study Summary 2 Implants, 1 Pat.

  14. FXA - Study Summary Comments: At Pre-OP, the index level has a smaller ROM when compared to the adjacent levels. The adjacent level below the index level tends to yield a slightly larger ROM compared to the adjacent level above the index level. After implantation the overall ROM decreased, which might be caused by the patient maintaining a pain relieving posture during x-ray assessment. The adjacent levels show a nearly symmetrical ROM. Starting at 3 month Post-OP, the ROM of the index level is increasing up to a mean value of 5.4° (12 months).

  15. FXA - Study Summary 2 Implants, 1 Pat.

  16. FXA - Study Summary Comments: Pre-OP, the index level has 90% of ROM in relation to the adjacent level above. After implantation, it can be seen that the motion sharing (independent from the overall ROM in absolute values) remained in a similar range over time. The index level ROM was between 40% and 60% for all time points.

  17. FXA - Study Case Examples Pre-OP s s s ROM = 5.7° ROM = 9.2° ROM = 11.5° C4-5 C5-6 C6-7

  18. FXA - Study Case Examples Post-OP (0 months) s s s ROM = 7.9° ROM = 1.8° ROM = 7.2° C4-5 C5-6 C6-7

  19. FXA - Study Case Examples Post-OP (3 months) s s s ROM = 8.8° ROM = 4.3° ROM = 15.2° C4-5 C5-6 C6-7

  20. FXA - Study Case Examples Post-OP (6 months) s s s ROM = 10.5° ROM = 4.8° ROM = 12.1° C4-5 C5-6 C6-7

  21. FXA - Study Case Examples Post-OP (12 months) s s s ROM = 10.8° ROM = 6.7° ROM = 14.2° C4-5 C5-6 C6-7

  22. FXA - Study Case Examples Change of COR over Time on Adjacent Level (different patient) s s s s Pre-OP Post-OP 6 months 12 months

  23. FXA - Study Summary General Comments and Limitations: • Patients need to get identical instructions in preparation for the x-ray taking • Different x-ray exposure settings were used for flexion and extension movements, which should be avoided • Most of the time the visibility of C7 was limited • In a few cases the x-ray images of various time points were incomplete • For long term follow-up (18+ months) only one patient was available

  24. FXA - Study Summary Further suggestions and ideas: • Definition of an “Surveillance Protocol”, mainly for improving consistency of x-rays • Defining parameters to detect the adjacent segment degeneration, i.e. changes in: • ROM • COR • AP-Translation • Disk Height • Comparison to alternative treatment options like xxx or yyy

  25. FXA - Study Summary Analysis Result Summary: • Index Level remains mobile with a ROM of 40-60% of the adjacent level over all time points • The adjacent level ROM remains mostly unchanged over time (except directly Post-OP) • The COR of the index level moves cranial and slightly posterior • The COR of the adjacent level seems not to be influenced by the Implant and remains constant over time • The ROM of the adjacent segments tends to slowly increase over time by a small amount (2-3°)

  26. With kind regards from Esslingen (Stuttgart, Germany) Thank You!

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