Knee Replacement Systems for Osteoarthritis

Overseen By Nirav Patel

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: LifeBridge Health

Disqualifiers: Bmi >40, Avascular necrosis, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 8

100 Participants Needed

Trial Summary

What is the purpose of this trial?

Patients with degenerative joint disease can effectively be treated with a primary total knee replacement to reduce pain and improve function in their daily lives. Theoretically, achievement of normal knee motion using a medial pivot design in total knee replacements can be recreated in comparison to single radius designs, which could lead to an improvement in post-surgical outcomes and satisfaction with the procedure. The aim of this study is to compare two types of implant designs (medial pivot and single radius) in a total knee replacement using clinical outcomes, patient reported outcomes, and overall function assessed by a specialized gait laboratory.

Will I have to stop taking my current medications?

The trial information does not specify whether you need to stop taking your current medications. It's best to discuss this with the trial coordinator or your doctor.

What data supports the effectiveness of the treatment Knee Replacement Systems for Osteoarthritis?

Research shows that medial-pivot knee systems, like the ones used in this trial, are designed to mimic natural knee movement, which may improve stability and patient satisfaction. Studies have reported high success rates and positive mid- to long-term outcomes for these systems, suggesting they can be effective for knee replacement. ^{1 2 3 4 5}

Is the knee replacement system generally safe for humans?

The medial pivot knee replacement design aims to mimic normal knee movement and has shown satisfactory mid-term safety outcomes, but more studies are needed to confirm long-term safety. The design has been used in various studies, and while it shows promise, comprehensive long-term safety data is still required. ^{1 6 7 8 9}

How does the MicroPort Evolution Medial-Pivot Knee System differ from other knee replacement treatments for osteoarthritis?

The MicroPort Evolution Medial-Pivot Knee System is unique because it uses a 'ball-in-socket' design to mimic natural knee movement, aiming to improve stability and function by closely replicating the knee's natural motion. This design contrasts with traditional knee replacements that may not replicate the knee's natural kinematics as effectively. ^{1 2 4 5 10}

Research Team

James Nace, MD

Principal Investigator

LifeBridge Health

Eligibility Criteria

This trial is for men and non-pregnant women aged 18-75 who need a knee replacement due to degenerative joint disease. They must be able to walk, attend follow-up visits, and not have had previous knee replacements or conditions that would affect walking tests.

Inclusion Criteria

You have a prosthetic device on the operative knee.

I can walk and have no issues with my other limb that would affect walking tests.

Subject is willing to provide informed consent to participate in the research study

Exclusion Criteria

You have a mental or neuromuscular condition that could make it risky for you to have surgery or could cause problems with the artificial body part after the surgery.

Subject has a Body Mass Index (BMI) >40

Subject has any condition, in the opinion of the Investigator that might interfere with the evaluation of the study objectives.

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Pre-operative

Pre-operative assessments and baseline measurements are conducted

1-2 weeks

1 visit (in-person)

Operative

Total Knee Arthroplasty is performed using either the Medial Pivot or Single Radius design

1 day

1 visit (in-person)

Post-operative Follow-up

Participants are monitored for post-surgical outcomes and complications

60 months

6 week, 6 month, 12 month, 24 month, 36 month, and 60 month follow-up visits

Treatment Details

Interventions

• MicroPort Evolution Medial-Pivot Knee System (Cruciate-substituting)
• Stryker Triathlon Tritanium Knee System (Condylar Stabilizing)

Trial Overview The study compares two types of knee implants: the MicroPort Evolution Medial-Pivot Knee System and the Stryker Triathlon Tritanium Knee System. It will assess which design better improves pain relief, function, and patient satisfaction after surgery.

Participant Groups

Group I: Single Radius Design Total Knee System Active Control 1 Intervention

Total Knee Arthroplasty will be done by implanting the Stryker Triathlon Tritanium Knee System into subjects.

Group II: Medial-Pivot Knee System Active Control 1 Intervention

Total Knee Arthroplasty will be done by implanting the MicroPort Medial Pivot Knee System into subjects.

MicroPort Evolution Medial-Pivot Knee System (Cruciate-substituting) is already approved in United States, European Union, Canada, Japan, Switzerland for the following indications:

Approved in United States as MicroPort Evolution Medial-Pivot Knee System for:

• Degenerative joint disease
• Primary total knee replacement

Approved in European Union as MicroPort Evolution Medial-Pivot Knee System for:

• Degenerative joint disease
• Primary total knee replacement

Approved in Canada as MicroPort Evolution Medial-Pivot Knee System for:

• Degenerative joint disease
• Primary total knee replacement

Approved in Japan as MicroPort Evolution Medial-Pivot Knee System for:

• Degenerative joint disease
• Primary total knee replacement

Approved in Switzerland as MicroPort Evolution Medial-Pivot Knee System for:

• Degenerative joint disease
• Primary total knee replacement

Who Is Running the Clinical Trial?

LifeBridge Health

Lead Sponsor

Trials

32

Recruited

4,500+

MicroPort Orthopedics Inc.

Industry Sponsor

Trials

33

Recruited

3,700+

Rubin Institute for Advanced Orthopedics

Collaborator

Trials

2

Recruited

180+

Findings from Research

The medial pivot TKA design showed a higher risk of revision compared to cruciate-retaining designs in Australia, with a hazard ratio of 1.4, indicating potential concerns about its long-term effectiveness.

Specific brands of the medial pivot design, such as the Advance II MP and GMK Sphere, had significantly higher revision rates, suggesting that not all medial pivot implants perform equally well in terms of survivorship.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Decreased Survival of Medial Pivot Designs Compared with Cruciate-retaining Designs in TKA Without Patellar Resurfacing. Øhrn, FD., Gøthesen, Ø., Låstad Lygre, SH., et al.[2022]

A systematic review of 8 randomized controlled trials involving 725 knees found no significant differences in clinical outcomes between medial pivot (MP) designs and posterior-stabilized (PS) designs in total knee arthroplasty, suggesting that both designs perform similarly.

The analysis indicated that while some measures favored PS or MP at different time points, none reached statistical significance, highlighting the need for more research to compare MP with other bearing types.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Medial Pivot Designs Versus Conventional Bearing Types in Primary Total Knee Arthroplasty: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Hoskins, W., Smith, G., Spelman, T., et al.[2023]

The medial-pivot total knee replacement (TKR) system demonstrated excellent survivorship rates of 99.2% at five years and 97.6% at eight years, which are comparable or superior to other cemented TKR systems.

Post-operative Knee Society Scores (KSS) averaged 87.9, indicating a high level of patient satisfaction and function, similar across various international centers.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Mid- to long-term outcomes of a medial-pivot system for primary total knee replacement: a systematic review and meta-analysis. Fitch, DA., Sedacki, K., Yang, Y.[2022]

In a study of 224 patients who underwent total knee replacement (TKR) using a second generation medial-pivot system, 94.6% reported being very satisfied or satisfied at the 2-month follow-up, indicating high patient satisfaction with this specific implant design.

Satisfaction rates improved to 99.4% after the first 50 surgeries, suggesting that surgeon experience with the system may enhance outcomes, and overall functional scores and range of motion were also satisfactory.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Patient satisfaction at 2 months following total knee replacement using a second generation medial-pivot system: follow-up of 250 consecutive cases. Van Overschelde, PP., Fitch, DA.[2020]

In a study of 1128 total knee arthroplasties (TKAs) using the ADVANCE® medial-pivot design, excellent mid-term clinical outcomes were observed, with high scores in range of motion and patient-reported outcomes after an average follow-up of five years.

The overall survivorship of the ADVANCE® MP TKAs was 99.2% at seven years, indicating a strong long-term success rate, although when accounting for lost follow-ups as failures, the survivorship dropped to 50.6% at seven years.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Mid-term clinical outcomes and survivorship of medial-pivot total knee arthroplasty-a mean five year follow-up based on one thousand, one hundred and twenty eight cases. Xiang, S., Wang, Y., Lv, C., et al.[2022]

In a study of 161 patients who underwent 179 total knee arthroplasties (TKAs), the survival rate of the third-generation TKA system was 97.7% at a minimum of 10 years, with no revisions needed for patellar component issues, indicating high efficacy and safety of the design.

The study showed significant improvement in patient function, with Hospital for Special Surgery scores increasing from an average of 47.7 preoperatively to 85.4 postoperatively, demonstrating effective functional outcomes after surgery.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Cruciate-retaining TKA using a third-generation system with a four-pegged tibial component: a minimum 10-year followup note. Schwartz, AJ., Della Valle, CJ., Rosenberg, AG., et al.[2021]

The study found that the asymmetric tibial insert design allows for better knee kinematics, showing a more posterior position and greater external rotation of the femoral component compared to the symmetric design during movement.

Despite these kinematic advantages, both designs resulted in low peak contact stresses (less than 9 MPa), indicating that the asymmetric design does not negatively impact joint stress and may offer clinical benefits.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

How does asymmetric tibial insert affect tibiofemoral kinematics and contact stresses in total knee Arthroplasty? Song, YD., Nakamura, S., Kuriyama, S., et al.[2022]

The medial pivot design in total knee arthroplasty (TKA) aims to replicate natural knee movement, potentially leading to better clinical outcomes and reduced stress on the knee joint.

Current mid-term clinical and radiographic results are promising, but further research is necessary to assess the long-term effectiveness and suitability of this design for atypical cases.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Medial pivot knee in primary total knee arthroplasty. Atzori, F., Salama, W., Sabatini, L., et al.[2022]

The study demonstrated that after anterior cruciate-sacrificing total knee arthroplasty (TKA), restoring proper tension in the ligaments can bring both rotational and varus-valgus stability of the knee back to near-normal levels.

It was found that achieving normal rotational stability does not require additional rotational constraints in the TKA system, as long as varus-valgus stability is effectively restored.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Varus-valgus and rotational stability in rotationally unconstrained total knee arthroplasty. Whiteside, LA., Kasselt, MR., Haynes, DW.[2005]

In a study of 74 Medial-Pivot knee implants followed for an average of 10 years, the average knee range of motion achieved was 110°, which was lower than the hypothesized 120° flexion.

The survivorship rate of the Medial-Pivot knee was 93% overall, indicating good long-term durability, with no cases of aseptic loosening observed, suggesting satisfactory clinical and radiological outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Total knee arthroplasty with the Medial-Pivot knee system: Clinical and radiological outcomes at 9.5 years' mean follow-up. Dehl, M., Bulaïd, Y., Chelli, M., et al.[2019]

References

1. United States pubmed.ncbi.nlm.nih.gov

Decreased Survival of Medial Pivot Designs Compared with Cruciate-retaining Designs in TKA Without Patellar Resurfacing. [2022]

2. United States pubmed.ncbi.nlm.nih.gov

Medial Pivot Designs Versus Conventional Bearing Types in Primary Total Knee Arthroplasty: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. [2023]

3. England pubmed.ncbi.nlm.nih.gov

Mid- to long-term outcomes of a medial-pivot system for primary total knee replacement: a systematic review and meta-analysis. [2022]

4. China pubmed.ncbi.nlm.nih.gov

Patient satisfaction at 2 months following total knee replacement using a second generation medial-pivot system: follow-up of 250 consecutive cases. [2020]

5. Germany pubmed.ncbi.nlm.nih.gov

Mid-term clinical outcomes and survivorship of medial-pivot total knee arthroplasty-a mean five year follow-up based on one thousand, one hundred and twenty eight cases. [2022]

6. United States pubmed.ncbi.nlm.nih.gov

Cruciate-retaining TKA using a third-generation system with a four-pegged tibial component: a minimum 10-year followup note. [2021]

7. Netherlands pubmed.ncbi.nlm.nih.gov

How does asymmetric tibial insert affect tibiofemoral kinematics and contact stresses in total knee Arthroplasty? [2022]

8. China pubmed.ncbi.nlm.nih.gov

Medial pivot knee in primary total knee arthroplasty. [2022]

9. United States pubmed.ncbi.nlm.nih.gov

Varus-valgus and rotational stability in rotationally unconstrained total knee arthroplasty. [2005]

10. France pubmed.ncbi.nlm.nih.gov

Total knee arthroplasty with the Medial-Pivot knee system: Clinical and radiological outcomes at 9.5 years' mean follow-up. [2019]