A Comparison of Wear Among Mobile and Fixed Bearing Knee Replacements

NCT01165957 | Completed

• 2 other identifiers: AORI2010-0102Study #09010
• Study Type: observational
• Target: 24
• Locations: 1 country
• Sites: 1

Brief Summary

The purpose of this study is to determine the amount of polyethylene wear associated with knee replacement designs that incorporate either a fixed or mobile bearing. Tibial polyethylene inserts retrieved from modular total knee replacements during revision operations will be analyzed by obtaining micro-CT images of the retrieved inserts. The components of total volumetric polyethylene loss, including wear associated with the medial articular, lateral articular and backside regions of the insert be quantified by comparing the worn insert with an unworn control. The investigators hypothesize that the fixed bearing inserts where the polyethylene is locked to the metal baseplate will demonstrate more volumetric wear than the mobile bearing inserts that are designed to slide or rotate on the metal baseplate.

Conditions

Osteoarthritis

Keywords

Knee replacement; Mobile and fixed bearings; Volumetric wear; Micro-CT analysis; Articular and backside wear

Outcome Measures

Primary Outcomes (1)

• Total Volumetric Wear

  Total volumetric polyethylene wear will be measured among mobile and fixed bearing tibial inserts retrieved during a revision surgery.

  At time of revision (average 46 months)

Secondary Outcomes (1)

• Local Volumetric Wear

  At time of revision (average 46 months)

Study Arms (2)

Mobile bearings

Tibial polyethylene inserts retrieved from total knee replacements where the insert is designed to slide or rotate on the metal baseplate.

Fixed bearings

Tibial polyethylene inserts retrieved from total knee replacements where the insert is locked to the metal baseplate.

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Retrieved polyethylene tibial inserts archived as part the Anderson Orthopaedic Research Institute's implant retrieval program.

You may qualify if:

• DePuy mobile and fixed bearing polyethylene tibial inserts retrieved after at least 12 months in vivo.
• Inserts terminally sterilized by gas plasma or with gamma radiation in oxygen-free barrier packaging.

You may not qualify if:

• Inserts that were sterilized by gamma radiation and exposed to oxygen in packaging.

Sponsors & Collaborators

• Anderson Orthopaedic Research Institute: lead
• DePuy Orthopaedics: collaborator

Study Sites (1)

Anderson Orthopaedic Research Institute

Alexandria, Virginia, 22306, United States

Location

Related Publications (2)

• McEwen HM, Barnett PI, Bell CJ, Farrar R, Auger DD, Stone MH, Fisher J. The influence of design, materials and kinematics on the in vitro wear of total knee replacements. J Biomech. 2005 Feb;38(2):357-65. doi: 10.1016/j.jbiomech.2004.02.015.

  PMID: 15598464 BACKGROUND

• Jennings LM, Bell CI, Ingham E, Komistek RD, Stone MH, Fisher J. The influence of femoral condylar lift-off on the wear of artificial knee joints. Proc Inst Mech Eng H. 2007 Apr;221(3):305-14. doi: 10.1243/09544119JEIM215.

  PMID: 17539585 BACKGROUND

Related Links

• Website for Anderson Orthopaedic Research Institute

MeSH Terms

Conditions

Osteoarthritis

Condition Hierarchy (Ancestors)

Arthritis; Joint Diseases; Musculoskeletal Diseases; Rheumatic Diseases

Study Officials

• Robert H Hopper, Jr., PhD

  Anderson Orthopaedic Research Institute

  STUDY DIRECTOR

Study Design

• Study Type: observational
• Observational Model: CASE CONTROL
• Time Perspective: RETROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: July 13, 2010
• First Posted: July 20, 2010
• Study Start: June 1, 2010
• Primary Completion: May 1, 2012
• Study Completion: May 1, 2012
• Last Updated: August 1, 2012

Record last verified: 2012-07

Locations

US (1)