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NCT Number: NCT04636190

Triathlon All-Polyethylene Tibia Outcomes Study

The purpose of this study is to evaluate the clinical functional results of the Triathlon All-Polyethylene Tibia Knee Device.

Active, Not Recruiting

This study is active but is not currently recruiting participants.

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Key information

Age range

18 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Michigan Orthopaedic Center, Lansing, Michigan, United States

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About this study

This study is a retrospectively enrolled, prospective evaluation of the Triathlon All-Polyethylene Tibia (APT) for patients who meet the eligibility criteria. The enrolled cases will be followed for outcomes measured to 10 years. A modular, Triathlon metal-backed tibia (MBT) and polyethylene insert construct will be used as a historical control.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusions:

  • Patient underwent primary TKA and is currently implanted with the Triathlon All-Polyethylene Tibia as well as compatible Stryker femoral and patellar components with no pending revision or removal.
  • Patient has signed an IRB-approved, study specific Informed Patient Consent Form.
  • Patient is a male or non-pregnant female and is 18 years of age or older at the time of study device implantation.
  • Patient is willing and able to comply with postoperative scheduled clinical and radiographic evaluations.

Exclusions:

  • Patient had an active or suspected latent infection in or about the affected knee joint at time of study device implantation.
  • Patient had distant foci of infection which could have caused hematogenous spread to the implant site at time of study device implantation.
  • Patient was skeletally immature at time of study device implantation.
  • Patient has a mental or neuromuscular disorder which would create an unacceptable risk of prosthesis instability, prosthesis fixation failure, or complications in postoperative care.
  • Patient's bone stock was compromised by disease, infection, or prior implantation which cannot provide adequate support and/or fixation to the prosthesis.
  • Patient had severe instability of the knee joint secondary to the absence of collateral ligament integrity and function.
  • Patient was immunologically suppressed or receiving steroids in excess of normal physiological requirements at the time of surgery (e.g. > 30 days duration of treatment).
  • Patient is a prisoner.

Treatment and study plan

Triathlon All-Polyethylene Tibia Knee

Device

Triathlon All-Polyethylene Tibia Knee is an all polyethylene resurfacing knee device using either a condylar stabilizing (CS) and posterior stabilizing (PS) device.

Primary outcomes

  1. Knee Society Score (KSS) Function

    Time frame: 10-years postoperative

    The Knee Society Clinical Rating System is comprised of two distinct sub-scores: one for pain, range of motion (ROM) and joint stability, and one for functional parameters. Sub-scores range from a potential minimum score of 0 to a maximum score of 100 points. Although the specific scores are not distinguished as "excellent," "good," "fair," or "poor," a higher value represents a better outcome postoperative.

Secondary outcomes

  1. Kaplan-Meier Survival Analysis

    Time frame: 10-years postoperative

    To present 10-year Kaplan-Meier survival analysis for the Triathlon APT

Sponsors and collaborators

Lead sponsor

Stryker Orthopaedics

Industry

Registry information

Official study title

A Retrospectively Enrolled and Prospectively Followed, Post-market, Multi-center Evaluation of the Clinical Outcomes of the Triathlon All-Polyethylene Tibia

Acronym: APT

Important dates

Study start
2021
Primary completion
2033
Study completion
2033
First posted
Nov 19, 2020
Registry last updated
Feb 27, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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