Working... Menu

iAssist vs. Conventional Instrumentation in Total Knee Arthroplasty

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT03111407
Recruitment Status : Active, not recruiting
First Posted : April 12, 2017
Last Update Posted : June 21, 2018
Information provided by (Responsible Party):
Zimmer Biomet ( Zimmer, GmbH )

Brief Summary:
The purpose of this prospective study is to evaluate Zimmer® iASSIST™ with respect to radiographic, clinical and economic outcomes and compared to conventional instrumentation in primary total knee arthroplasty (NexGen or Persona knee implants).

Condition or disease Intervention/treatment Phase
Avascular Necrosis Post-traumatic; Arthrosis Knee Osteoarthritis Procedure: total knee arthroplasty Not Applicable

Detailed Description:

The study design is a prospective, multicenter, comparative outcome study. The study requires each site to obtain IRB (Institutional Review Board) approval prior to study enrollment. All potential study subjects will be required to participate in the Informed Consent Process.

All study subjects will undergo preoperative clinical evaluations prior to their total knee arthroplasty. Investigators will collect clinical data for 12 months. Follow-up clinical visits include 3 and 12 months post-operatively.

The primary endpoint of this study is defined as component alignment as determined using long leg X-Rays. The secondary endpoint will be to evaluate the Knee Society Score, EQ-5D (EuroQol-5Dimensions) scoring system, operating room time, blood loss and complications

Layout table for study information
Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 100 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Intervention Model Description: 2 groups of patients: 1 will have the knee prosthesis implanted with iAssist and the other with conventional instrumentation.
Masking: Single (Participant)
Masking Description: Study patients will not know if their knee prosthesis will be implanted with iAssist or with conventional instrumentation
Primary Purpose: Treatment
Official Title: Evaluation of Zimmer® iASSIST™ vs. Conventional Instrumentation in Total Knee Arthroplasty: Radiographic, Clinical and Economic Outcomes
Actual Study Start Date : April 2014
Estimated Primary Completion Date : September 2019
Estimated Study Completion Date : December 2019

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Knee Replacement

Arm Intervention/treatment
iAssist group
patients will have primary total knee arthroplasty with the iAssist. The iAssist Knee System is a computer assisted stereotaxic surgical instrument system to assist the surgeon in the positioning of orthopedic implant system components intra-operatively. It involves surgical instruments and position sensors to determine alignment axes in relation to anatomical landmarks and to precisely position alignment instruments and implant components relative to these axes.
Procedure: total knee arthroplasty
surgical procedure in which damaged parts of the knee joint are replaced with an implant.

conventional instrumentation
patients will have primary total knee arthroplasty with the conventional instrumentation.
Procedure: total knee arthroplasty
surgical procedure in which damaged parts of the knee joint are replaced with an implant.

Primary Outcome Measures :
  1. component alignment [ Time Frame: 1 year ]
    Assess the differences in component alignment, between iASSIST™ and conventional instrumentation in primary total knee arthroplasty (TKA) procedures.

Secondary Outcome Measures :
  1. Knee Society Score and EQ-5D [ Time Frame: 1 year ]
    Assess the differences in Knee Society Score and EQ-5D between iASSIST™ and conventional instrumentation in primary TKA procedures.

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

Layout table for eligibility information
Ages Eligible for Study:   18 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Patient is male or female
  • Patient needs a primary total knee replacement using the NexGen LPS Flex or Persona knee implant
  • Patient is diagnosed with non-inflammatory degenerative joint disease (e.g., osteoarthritis, post-traumatic arthritis, avascular necrosis, etc.)
  • Patient is over 18 years old
  • Patient is able to:

    • Understand what participation in the study entails and willing to consent (patient or his/her legal guardian) to participate in the study by signing and dating an IRB/EC (ethics committee) approved inform consent form, and
    • Follow surgeon/staff instructions, and
    • Return for all follow-up evaluations, and
    • Able and willing to undergo a preoperative full-leg, standing radiographs and/or CT-scan
  • Patient meets an acceptable preoperative medical clearance and is free of or treated for cardiac, pulmonary, hematological or other conditions that would pose excessive operative risk.
  • Patient has a presence of varus or valgus deformity of 15 degrees or less.

Exclusion Criteria:

  • Patient is currently enrolled in an investigational new drug or device study.
  • Patient has an active infection (including septic knee, distant infection, or osteomyelitis).
  • Patient has severe hip arthrosis.
  • Patient has neurological disorders (including, but not limited to Parkinson's disease).
  • Patient has had a prior ipsilateral unicompartmental knee arthroplasty, TKA, knee fusion or patellectomy.
  • Patient has hip or knee ankylosis.
  • Patient has inflammatory joint disease.
  • Patient has rheumatoid knee arthritis.
  • Patient has indications of intra- and/or extra-articular deformations that would eliminate or tend to eliminate adequate implant support or prevent the use of an appropriately sized implant, such as polio, history of tibial plateau fracture, etc.
  • Patient has any metal within 150 mm of the joint line for the operative-side knee.
  • Patient has knee deformities greater than 15 degrees of fixed varus, valgus, or flexion contracture on initial physical examination.
  • Female who is pregnant or lactating.
  • Patient currently involved in any personal injury litigation, medical-legal or worker's compensation claims.
  • Patient has arterial disease or stents that would exclude the use of a tourniquet.
  • Patient has insufficient quality or quantity of bone to support the implant due to prior knee surgery (or surgeries), cancer, metabolic bone disease, osteoporosis/osteopenia (diagnosed or treated with medication), active/old/remote infection, etc.
  • Patient has a mental condition that may interfere with his/her ability to give an informed consent or interfere with his/her ability or willingness to fulfill the requirements of the study.
  • Patient has a condition that would place excessive demands on the implant (e.g., Charcot's joints, muscle deficiencies, multiple joint disabilities, skeletal immaturity, etc.).
  • Patient has collateral ligament insufficiency.
  • Patient has an immunosuppressive disorder (e.g., AIDS, etc.) that would require cytotoxic drugs, corticosteroids, large dose of irradiation, or antilymphocytic serum.
  • Patient has an existing condition that would, in the opinion of the investigator, compromise participation or follow-up in this study.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT03111407

Layout table for location information
Hospital El Angel, S.A.
Malaga, Spain, 29007
Hospital Unviersitario Son Espases
Palma de Mallorca, Spain, 07010
Universitätsklinik Balgrist
Zurich, Switzerland, 8008
Sponsors and Collaborators
Zimmer, GmbH
Layout table for investigator information
Study Director: Paola Vivoda, Ass.Direct Zimmer Biomet

Layout table for additonal information
Responsible Party: Zimmer, GmbH Identifier: NCT03111407     History of Changes
Other Study ID Numbers: CSE2012-05K
First Posted: April 12, 2017    Key Record Dates
Last Update Posted: June 21, 2018
Last Verified: June 2018
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No

Layout table for additional information
Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No

Keywords provided by Zimmer Biomet ( Zimmer, GmbH ):
primary total knee arthroplasty

Additional relevant MeSH terms:
Layout table for MeSH terms
Osteoarthritis, Knee
Joint Diseases
Musculoskeletal Diseases
Rheumatic Diseases
Pathologic Processes