Mechanics Analysis of Patients Having a Sigma Mobile Bearing TKA (Sigma MB TKA)

This study has been completed.
Sponsor:
Collaborator:
DePuy Orthopaedics
Information provided by (Responsible Party):
The University of Tennessee Knoxville
ClinicalTrials.gov Identifier:
NCT01714492
First received: October 23, 2012
Last updated: January 21, 2014
Last verified: January 2014
  Purpose

Utilize previously developed mathematical model to determine in vivo knee mechanics (kinematics, forces, stresses, areas and sound) for subjects having a Sigma Posterior Stabilizing (PS) mobile bearing (MB) total knee arthroplasty (TKA). There are several hypotheses for this study, although the most prominent is: Subjects having a Sigma RP PS TKA will experience polyethylene bearing rotation at 10 years post-operative, similar to their previous evaluations at six months, two years and five years.


Condition Intervention
Knee Prosthesis
Knee Replacement Arthroplasty
Device: Sigma Posterior Stabilizing Rotating Platform TKA Beaded Poly

Study Type: Observational
Study Design: Observational Model: Cohort
Time Perspective: Cross-Sectional
Official Title: In Vivo Mechanics Analysis of Patients Having a Sigma Mobile Bearing TKA

Resource links provided by NLM:


Further study details as provided by The University of Tennessee Knoxville:

Primary Outcome Measures:
  • In Vivo Linear Knee Kinematics From Fluoroscopy Evaluation During Deep Knee Bend Activity [ Time Frame: 10 yrs post-operative ] [ Designated as safety issue: No ]
    The values that were reported indicate the motion of the contact point from full extension to patient's maximum flexion. Throughout flexion, if the point translated forward (anteriorly) atop the tibial tray, the number was reported as positive. If the point traveled backwards (posteriorly) atop the tibial tray, the number was reported as negative.

  • Femoral Axial Rotation With Respect to the Tibia During Deep Knee Bend Activity [ Time Frame: 10 yrs post-operative ] [ Designated as safety issue: No ]
  • Range of Motion During Flexion of Deep Knee Bend Activity [ Time Frame: 10 yrs post-operative ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • In Vivo Knee Force Values From Fluoroscopy Evaluation During Deep Knee Bend Activity [ Time Frame: 10 yrs post-operative ] [ Designated as safety issue: No ]
    The intended unit of measure is "times Body Weight" (or xBW), relating to a ratio.

  • Condyle Contact Area at Maximum Flexion During Deep Knee Bend Activity [ Time Frame: 10 yrs post-operative ] [ Designated as safety issue: No ]
  • Condyle Contact Stress at Maximum Flexion During Deep Knee Bend Activity [ Time Frame: 10 yrs post-operative ] [ Designated as safety issue: No ]

Enrollment: 8
Study Start Date: April 2012
Study Completion Date: November 2012
Primary Completion Date: November 2012 (Final data collection date for primary outcome measure)
Groups/Cohorts Assigned Interventions
Sigma Posterior Stabilizing Rotating Platform TKA Beaded Poly
subjects implanted with the Sigma Posterior Stabilizing Rotating Platform TKA including a polyethylene insert with 4 beads
Device: Sigma Posterior Stabilizing Rotating Platform TKA Beaded Poly
Sigma PS RP TKA including a polyethylene insert with 4 beads

Detailed Description:

Additional hypotheses:

  • Subjects having a Sigma RP PS TKA will experience full ideal femorotibial contact mechanics.
  • Subjects having a Sigma RP PS TKA will experience optimal cam/post mechanics.
  • Subjects having a Sigma RP PS TKA will experience continuous axial rotation in deep flexion.
  • Subjects having a Sigma RP PS TKA will experience optimal distribution of tibio-femoral and cam/post contact forces over a broad area on the post.
  • Subjects having a Sigma RP PS TKA will experience a smooth transition of the cam on the post, not an abrupt slide as seen with fixed bearing PS TKA.
  • The use of the sound sensors will detect cam/post contact mechanics under in vivo conditions.
  Eligibility

Ages Eligible for Study:   40 Years to 85 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Sampling Method:   Probability Sample
Study Population

Patients are eight mobile bearing subjects that were implanted over 10 years ago with a custom polyethylene insert that has four beads rigidly inserted into the polyethylene component.

Criteria

Inclusion Criteria:

  • At least six months post-operative
  • Between 40-85 years of age
  • Have a body weight of less than 250 lbs.
  • Judged clinically successful with a AKS greater than 90
  • Have the DePuy Sigma mobile bearing TKA
  • Good-to-excellent post-operative passive flexion
  • Must be willing to sign the IC and HIPAA forms.

Exclusion Criteria:

  • Pregnant females
  • Those not willing to sign the IC and HIPAA forms
  Contacts and Locations
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, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01714492

Locations
United States, Colorado
Porter Adventist Hospital, Colorado Joint Replacement
Denver, Colorado, United States, 80210
United States, Tennessee
Perkins Hall, The University of Tennessee
Knoxville, Tennessee, United States, 37996
Science and Engineering Research Facility, The University of Tennessee
Knoxville, Tennessee, United States, 37996
Sponsors and Collaborators
The University of Tennessee Knoxville
DePuy Orthopaedics
Investigators
Principal Investigator: Richard D Komistek, Ph. D. The University of Tennessee
Principal Investigator: Dennis A Douglas, MD Colorado Joint Replacement
  More Information

No publications provided

Responsible Party: The University of Tennessee Knoxville
ClinicalTrials.gov Identifier: NCT01714492     History of Changes
Other Study ID Numbers: 11019, R01 1373 424
Study First Received: October 23, 2012
Results First Received: May 23, 2013
Last Updated: January 21, 2014
Health Authority: United States: Institutional Review Board

Keywords provided by The University of Tennessee Knoxville:
Total Knee Arthroplasty (TKA)
in vivo mechanics
kinematics
fluoroscopy

ClinicalTrials.gov processed this record on October 22, 2014