Biomaterials Expert Barred from Testifying About Corporate Knowledge and Intent
Posted on August 5, 2025 by Expert Witness Profiler
Connie Thacker is one of tens of thousands of individuals who have filed suit against Ethicon for injuries after treatment with Ethicon’s pelvic mesh devices.
Plaintiff Connie Thacker filed a motion asking the Court to preclude defense expert Dr. Uwe Klinge from offering testimony on certain subjects.
Biomaterial Expert Witness
Dr. Uwe Klinge is a former abdominal surgeon with specialized expertise in biomaterial science and surgical mesh design. His research has focused on mesh-tissue interactions, complications, and material performance.
He previously served as a consultant to Ethicon, advising on mesh development, including pore size, weight, and composition. Klinge is widely recognized for his contributions to improving the safety and design of implantable mesh devices.
Discussion by the Court
Klinge’s testimony on PVDF mesh as an alternative design
Thacker offered Klinge’s opinion that PVDF mesh was a safer alternative design. The Court excluded this testimony as irrelevant. Since Klinge is a general expert, his opinion needed support from a case-specific expert showing PVDF mesh would have prevented Thacker’s injuries. No such testimony was offered. Without that link, the Court held the opinion did not “fit” the facts of the case under Rule 702.
Klinge’s testimony on Ultrapro mesh as an alternative design
Klinge also opined that Ultrapro mesh was a safer alternative for the TVT-S device. The Court found the opinion relevant—since Dr. Rosenzweig, a case-specific expert, supported the feasibility of Ultrapro mesh. However, the Court excluded Klinge’s opinion as unreliable under Daubert. He cited no testing, peer-reviewed studies, or scientific basis. Ethicon’s internal documents and a Turkish study (not disclosed in his report) were deemed insufficient.
Klinge’s testimony on fraying and particle loss in Prolene Soft mesh
Defendants challenged Klinge’s opinion that Prolene Soft mesh frays and sheds particles, arguing it was based on data from a different mesh type (Prolene). The Court allowed the testimony. It found insufficient evidence to determine if the distinction between Prolene and Prolene Soft rendered his opinion unreliable. Defendants may revisit the issue at trial.
Klinge’s testimony on Ethicon’s state of mind and corporate conduct
Defendants sought to bar Klinge from testifying about Ethicon’s knowledge or corporate behavior. Thacker did not oppose the motion. The Court granted it, precluding Klinge from offering such testimony.
Held
The Court granted in part and denied in part the Plaintiff’s motion to exclude the testimony of the defense expert Uwe Klinge.
Key Takeaways:
The Court partially excluded Dr. Uwe Klinge’s expert testimony, barring his opinions on PVDF and Ultrapro mesh as safer alternative designs due to lack of case-specific support and scientific reliability. However, it allowed his testimony on Prolene Soft mesh fraying and particle loss. The Court also prohibited him from discussing Ethicon’s corporate intent or state of mind.
Please refer to the blogs previously published about this case:
Obstetrics and Gynecology Expert’s Testimony on Mesh Porosity and Stiffness Admitted
Urogynecology Expert’s Opinion on Continuum of Care Admitted
Biomedical Engineering Expert’s Testimony on Product Warnings Admitted
Case Details:
| Case Caption: | Thacker V. Ethicon Inc. |
| Docket Number: | 5:20cv50 |
| Court Name: | United States District Court, Kentucky Eastern |
| Order Date: | July 08, 2025 |
