Mechanics Analysis of Patients Having a Sigma Mobile Bearing TKA

Knee Prosthesis Clinical Trial

— Sigma MB TKA  

Official title:

In Vivo Mechanics Analysis of Patients Having a Sigma Mobile Bearing TKA

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01714492
• Other study ID #: 11019
• Secondary ID: R01 1373 424
• Status: Completed
• Start date: April 2012
• Est. completion date: November 2012

Study information

• Verified date: October 2019
• Source: The University of Tennessee, Knoxville
• Contact: n/a
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

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.

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.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 8
• Est. completion date: November 2012
• Est. primary completion date: November 2012
• Accepts healthy volunteers: No
• Gender: All
• Age group: 40 Years to 85 Years

Eligibility

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

Related Conditions & MeSH terms

• Knee Prosthesis
• Knee Replacement Arthroplasty

Intervention

Device:
• Sigma Posterior Stabilizing Rotating Platform TKA Beaded Poly
Sigma PS RP TKA including a polyethylene insert with 4 beads

Locations

Country	Name	City	State
United States	Porter Adventist Hospital, Colorado Joint Replacement	Denver	Colorado
United States	Perkins Hall, The University of Tennessee	Knoxville	Tennessee
United States	Science and Engineering Research Facility, The University of Tennessee	Knoxville	Tennessee

Sponsors (2)

Lead Sponsor	Collaborator
The University of Tennessee, Knoxville	DePuy Orthopaedics

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	In Vivo Linear Knee Kinematics From Fluoroscopy Evaluation During Deep Knee Bend Activity	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.	10 yrs post-operative
Primary	Femoral Axial Rotation With Respect to the Tibia During Deep Knee Bend Activity		10 yrs post-operative
Primary	Range of Motion During Flexion of Deep Knee Bend Activity		10 yrs post-operative
Secondary	In Vivo Knee Force Values From Fluoroscopy Evaluation During Deep Knee Bend Activity	The intended unit of measure is "times Body Weight" (or xBW), relating to a ratio.	10 yrs post-operative
Secondary	Condyle Contact Area at Maximum Flexion During Deep Knee Bend Activity		10 yrs post-operative
Secondary	Condyle Contact Stress at Maximum Flexion During Deep Knee Bend Activity		10 yrs post-operative