Migration and Survival of All-polyethylene Tibial All Poly Components Compared to the Metal-backed Modular Components of the Triathlon CS Total Knee System. A Single Center RSA Study

NCT04358575 | Completed DMC

• 1 other identifier: Allpoly Triathlon CS
• Study Type: interventional
• Target: 60
• Locations: 0 countries
• Sites: N/A

Brief Summary

The primary objective is the assessment of prosthetic migration results after two years of the Triathlon CS Knee System with all-polyethylene tibial components compared to the Triathlon CS Knee System with metal-backed modular components by means of Roentgen Stereophotogrammetry.

Conditions

Arthritis

Outcome Measures

Primary Outcomes (1)

• Migration, measured by means of RSA

  Migration (MTPM in mm) of the prosthesis with respect to the host bone measured by means of roentgen stereophotogrammetric analysis (RSA)

  2 years

Secondary Outcomes (6)

• Migration, measured by means of RSA

  10 years

• Investigation of clinical performance and patient outcome with the Knee Society Score (KSS)

  pre-operative, 3 months, 1, 2, 5, 7 and 10 years

• Investigation of clinical performance and patient outcome with the Knee Injury and Osteoarthritis Outcome Score (KOOS) patient questionnaire

  pre-operative, 3 months, 1, 2, 5, 7 and 10 years

• Investigation of clinical performance and patient outcome with EuroQuol-5 dimension (EQ-5D) patient questionnaire

  pre-operative, 3 months, 1, 2, 5, 7 and 10 years

• Investigation of clinical performance and patient outcome with the Forgotten Joint Score (FJS) patient questionnaire.

  pre-operative, 3 months, 1, 2, 5, 7 and 10 years

Study Arms (2)

All-polyethylene tibial components

EXPERIMENTAL

Triathlon CS Knee System with all-polyethylene tibial components

Device: Triathlon CS Knee System with all-polyethylene tibial components

Metal-backed modular components

ACTIVE COMPARATOR

Triathlon CS Knee System with metal-backed modular components

Device: Triathlon CS Knee System with metal-backed modular components

Interventions

Triathlon CS Knee System with all-polyethylene tibial components DEVICE

Primary Total Knee Replacement

Also known as: Stryker Orthopaedics

All-polyethylene tibial components

Triathlon CS Knee System with metal-backed modular components DEVICE

Primary Total Knee Replacement

Also known as: Stryker Orthopaedics

Metal-backed modular components

Eligibility Criteria

• Age: 40 Years - 75 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

1\. The subject is morbidly obese, defined as Body Mass Index (BMI) of \> 40. 2. Patient has a flexion contracture of 15° and more. 3. Patient has a varus/valgus contracture of 15° and more. 4. Patients with a pre-operative knee score of \>70. 5. The subject has a history of total or unicompartmental reconstruction of the affected joint. 6. The subject will be operated bilaterally. 7. Patients who had a Total Hip Arthroplasty (THA) on contralateral and/or ipsilateral side within the last year that is considered to have an unsatisfactory outcome (Patients with contralateral and/or ipsilateral THA \> 1 year ago with good outcome can be included in the study). 8. Patients who had a Total Knee Arthroplasty (TKA) on contralateral side within the last 6 months that is considered to have an unsatisfactory outcome. (Patients with contralateral TKA \> 6 months ago with good outcome can be included in the study). 9. The subject has an active or suspected latent infection in or about the knee joint. 10. Osteomyelitis 11. Sepsis 12. Patient who is expected to need lower limb joint replacement for another joint within one year. 13. The subject has a neuromuscular or neurosensory deficiency, which would limit the ability to assess the performance of the device. 14. The subject has a systemic or metabolic disorder leading to progressive bone deterioration. 15. The subject is immunologically suppressed or receiving steroids in excess of normal physiological requirements. 16. The subject's bone stock in compromised by disease or infection which cannot provide adequate support and/or fixation to the prosthesis. 17. The subject has had a knee fusion to the affected joint. 18. Female patients planning a pregnancy during the course of the study. 19. The patient is unable or unwilling to sign the Informed Consent specific to this study

Contact the study team to discuss eligibility requirements. They can help determine if this study is right for you.

Sponsors & Collaborators

• Region Skane: lead
• Stryker SA: collaborator

MeSH Terms

Conditions

Arthritis

Condition Hierarchy (Ancestors)

Joint Diseases; Musculoskeletal Diseases

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: April 20, 2020
• First Posted: April 24, 2020
• Study Start: February 1, 2014
• Primary Completion: October 1, 2014
• Study Completion: April 29, 2025
• Last Updated: September 4, 2025

Record last verified: 2025-09