Study of Surgical Technique With Use of Single-radius Prosthesis in Total Knee Replacement

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: NCT01505452
Recruitment Status : Completed
First Posted : January 6, 2012
Last Update Posted : December 19, 2017
Stryker Orthopaedics
Information provided by (Responsible Party):
Ormonde M. Mahoney, MD, Athens Orthopedic Clinic, P.A.

Brief Summary:
The purpose of this study is to clinically demonstrate a phenomenon of measurement error that can occur during placement of a specific type of total knee replacement prosthesis (single radius femoral component) using a certain type of surgical technique (flexion/extension gap balancing).

Condition or disease
Arthritis of Knee

Study Type : Observational
Actual Enrollment : 43 participants
Observational Model: Other
Time Perspective: Cross-Sectional
Official Title: Translational Error in Flexion-extension Gap Balancing With Singe Radius Total Knee Arthroplasty
Study Start Date : November 2011
Actual Primary Completion Date : February 2014
Actual Study Completion Date : February 2014

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Knee Replacement
U.S. FDA Resources

Primary Outcome Measures :
  1. Difference in varus/vagus laxity of the knee joint measured with the knee positioned at a 90 degree angle with posteriorly stabilized vs. cruciate retaining trails in place. [ Time Frame: At the time of the surgical procedure ]
    During the surgical procedure each participant will undergo measurement of varus/valgus laxity (in degrees) at 90 degrees knee flexion using both types of trial implants in sequence. We will evaluate whether the difference of varus/valgus laxity between the two surgical conditions is correlated to change in anterior/posterior relative position of the tibia (relative to femur) measured between the two conditions. A positive correlation between these two variables (change of position to change of laxity) would demonstrate a potential for measurement error that could occur during surgical procedures if position change of the tibia is not accounted for. All outcomes for this study are measured during the surgical procedure.

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Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population
Clinic based population (patients undergoing total knee replacement at an orthopedic surgery clinic).

Inclusion Criteria:

  • Scheduled to undergo primary total knee arthroplasty performed by the principal investigator
  • Use of a single radius posterior-stabilized TKA prosthesis is planned
  • Spinal anesthetic is planned
  • Diagnosis of osteoarthritis
  • Has normal knee ligaments with no history of previous injury or surgery to ligaments, or other pathologic condition
  • Has at least 100 degrees knee flexion preoperatively (measured by long goniometer)
  • Gives valid informed consent
  • Age 18 years or older

Exclusion Criteria:

  • Patient receives general anesthetic
  • Diagnosis other than osteoarthritis (e.g., rheumatoid arthritis, avascular necrosis, post-traumatic arthritis)
  • History of any prior knee ligament injury, or any surgery to ligaments
  • Any connective tissue disease affecting integrity of the ligaments (must have normal ligaments)
  • History of long bone fracture in the affected leg
  • Flexion contracture that would interfere with ability to establish extension gap reliably (judgment of investigator)
  • Maximum pre-operative knee flexion is less than 100 degrees.
  • Patient is non-ambulatory
  • Any preclusion or inability to use navigation
  • Treatment with single radius posterior stabilized TKA prosthesis is not indicated
  • Participation is not in best interest of patient for any reason
  • Cannot or does not give valid informed consent
  • Female patient who is currently pregnant
  • Age less than 18 years
  • Body mass index greater than 40 kg/(m*m)
  • Incarcerated

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): NCT01505452

United States, Georgia
Athens Orthopedic Clinic
Athens, Georgia, United States, 30606
St Mary's Hospital
Athens, Georgia, United States, 30606
Sponsors and Collaborators
Athens Orthopedic Clinic, P.A.
Stryker Orthopaedics
Principal Investigator: Ormonde M Mahoney, MD Athens Orthopedic Clinic

Responsible Party: Ormonde M. Mahoney, MD, Principal Investigator, Athens Orthopedic Clinic, P.A. Identifier: NCT01505452     History of Changes
Other Study ID Numbers: AOC-OM-Stryker-2009-0019
First Posted: January 6, 2012    Key Record Dates
Last Update Posted: December 19, 2017
Last Verified: December 2017