Evaluation of 5-year Survival and Clinical Outcomes in Patients Undergoing Total Knee Arthroplasty With a Polyethylene Tibial Component (ALLPOLY-TKA)

April 15, 2026 updated by: Stefano Zaffagnini, Istituto Ortopedico Rizzoli

Total knee arthroplasty (TKA) is one of the most successful procedures in orthopedic surgery for treating advanced knee osteoarthritis, providing pain relief, functional recovery, and improved quality of life. Advances in implant design and materials have further enhanced joint kinematics and patient satisfaction.

An aging population has increased the number of elderly patients with comorbidities, potentially affecting surgical outcomes and implant longevity. Polyethylene has long been used in knee prostheses; early all-polyethylene tibial components were abandoned due to high wear and failure rates, in favor of metal-backed designs, which became the gold standard.

Recently, highly cross-linked ultra-high-molecular-weight polyethylene (UHMWPE) has renewed interest in all-polyethylene tibial components, although their use remains limited. These implants offer potential advantages, including elimination of locking mechanism failures, reduced backside wear, lower costs, and possibly better load distribution.

Evidence from registries, systematic reviews, and meta-analyses shows that 15-year survival of all-polyethylene tibial components is comparable or even superior to metal-backed designs, with no significant differences in clinical-functional outcomes. Additionally, all-poly components are significantly less expensive.

Given these findings, increasing their use and evaluating outcomes in Italy is warranted. The aim of the present study is to assess implant survival of the Link Symphoknee prosthesis with an all-polyethylene tibial component, along with clinical-functional outcomes and post-discharge readmission rates in patients treated at the Rizzoli Orthopaedic Institute.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Not yet recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
78

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Locations

  • Italy
      • Bologna, Italy, 40136
        • IRCCS Rizzoli Orthopedic Institute

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  1. Male and female subjects aged ≥50 and ≤85 years who are candidates for primary cemented total knee arthroplasty based on physical examination and medical history, including a diagnosis of severe knee pain and disability due to at least one of the following conditions:

    1. Primary or secondary osteoarthritis
    2. Collagen disorders and/or avascular necrosis of the femoral condyle
    3. Moderate valgus, varus, or flexion deformities (Hip-Knee-Ankle angle within ±15°).
  2. Patients who provide consent and are able to complete the scheduled study procedures and follow-up assessments.
  3. Patients who sign the informed consent approved by the Ethics Committee.

Exclusion Criteria:

  1. Patients under 50 years of age and over 85 years of age;
  2. Diagnosis of rheumatoid arthritis;
  3. Patients with a contralateral joint prosthesis on the same side;
  4. Coronal plane deformity with a Hip-Knee-Ankle (HKA) angle greater than 15 degrees in varus or valgus.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: TKA
Implantation of the Link Symphoknee prosthesis with an all-polyethylene tibial component.
Device: Total knee arthroplasty
Implantation of the Link Symphoknee prosthesis with an all-polyethylene tibial component

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Implant failure
Time Frame: Up to 5 years post-surgery
It is defined as revision of the prosthesis for any reason-septic, aseptic, or traumatic.
Up to 5 years post-surgery

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Knee injury and Osteoarthritis Outcome Score (KOOS)
Time Frame: Up to 5 years post-surgery
It is a subjective score consisting of 42 questions divided into 5 main domains. These domains assess different aspects of symptoms and daily activities, as well as knee-related quality of life.
Up to 5 years post-surgery
Forgotten Joint Score (FJS)
Time Frame: Up to 5 years post-surgery
The Forgotten Joint Score (FJS-12) is a patient-reported outcome measure consisting of 12 questions that assesses how frequently a patient forgets they have a joint prosthesis during daily activities. It measures the patient's perception of the artificial joint rather than pain or function alone, with higher scores (0-100) indicating better "forgetting" of the joint
Up to 5 years post-surgery
Visual Analog Scale (VAS) pain
Time Frame: Up to 5 years post-surgery
A 10-point unidimensional visual analog scale (VAS) for pain assessment, consisting of a 10 cm horizontal line ranging from "no pain" (0) to "worst imaginable pain" (10). The patient marks their perceived pain intensity on the line, and the distance from zero is measured to quantify pain. It is also used pre- and post-operatively to assess lateral knee pain; a score >2 is considered the presence of lateral compartment pain, while ≤2 indicates its absence
Up to 5 years post-surgery
VAS Satisfaction
Time Frame: Up to 5 years post-surgery
Intraoperative and postoperative complications will be recorded. Any hospital readmissions within 90 days of discharge after the arthroplasty procedure will also be documented
Up to 5 years post-surgery
Hip-Knee-Ankle angle (HKA)
Time Frame: Up to 5 years post-surgery
It is the angle that measures the mechanical alignment of the lower limb, drawn between the hip, knee, and ankle axes on a weight-bearing radiograph. It is used to assess whether the leg is neutrally aligned or shows varus or valgus deformity
Up to 5 years post-surgery

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Istituto Ortopedico Rizzoli

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
May 1, 2026

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
October 1, 2032

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
October 1, 2032

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
April 15, 2026

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
April 15, 2026

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
April 22, 2026

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
April 22, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
April 15, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
April 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • ALLPOLY-TKA

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Arthropathy of Knee

Clinical Trials on Total knee arthroplasty

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Cookie Settings

We use cookies to ensure that we give you the best experience on our website. For more details carefully read our Privacy and Cookies Policy. ...>>>You can change your preferences or withdraw your consent at any time by deleting the cookies from your website or computer as described in the policy. Please accept it and choose your preferences by ticking the corresponding boxes in the "Manage Settings" section below. Please carefully read our Terms of Service before you proceed with using any part of this website.
«Manage Settings