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Updated: Jan 25, 2026
07:33
In Vitro Application of a Wireless Sensor in Flexion-Extension Gap Balance of Unicompartmental Knee Arthroplasty
Published on: May 5, 2023
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Modular junction fractures in a modern rotating-platform knee arthroplasty system
Ugonna Ihekweazu1, P Maxwell Courtney2, Elexis C Baral3
1Adult Reconstruction & Joint Replacement Division, Hospital for Special Surgery, New York, NY, USA.
Arthroplasty Today
|April 26, 2019
Summary
This study details four cases of DePuy Sigma TC3 RP knee prosthesis failure after revision surgery. Fatigue fractures at the femoral adapter bolt and sleeve caused component failure, leading to pain and mechanical symptoms.
Area of Science:
- Orthopedic Surgery
- Biomaterials Engineering
- Failure Analysis
Background:
- Revision total knee arthroplasty (TKA) aims to restore function but can be complicated by implant failure.
- The DePuy Sigma TC3 RP prosthesis is used in TKA procedures.
Observation:
- Four patients experienced pain and mechanical symptoms post-revision TKA with the DePuy Sigma TC3 RP prosthesis.
- Radiographs revealed femoral component failure at the modular junction.
- Retrieved implants showed fractures at the femoral adapter bolt and sleeve.
Findings:
- Microscopic analysis indicated fatigue fractures in the femoral locking bolt and adapter sleeve.
- These fractures are attributed to cyclic loading, a common stress in joint replacements.
- This is the first case series to document this specific failure mechanism in the DePuy Sigma TC3 RP prosthesis.
Implications:
- Understanding this failure mode is crucial for improving the design and longevity of TKA components.
- Highlights the need for careful patient selection and surgical technique in revision TKA.
- Informs future research into fatigue resistance of modular junctions in orthopedic implants.
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