Mechanics Analysis of Patients Having a Sigma Mobile Bearing TKA
- Conditions
- Knee ProsthesisKnee Replacement Arthroplasty
- Interventions
- Device: Sigma Posterior Stabilizing Rotating Platform TKA Beaded Poly
- Registration Number
- NCT01714492
- Lead Sponsor
- The University of Tennessee, Knoxville
- Brief 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.
- 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.
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- All
- Target Recruitment
- 8
- 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.
- Pregnant females
- Those not willing to sign the IC and HIPAA forms
Study & Design
- Study Type
- OBSERVATIONAL
- Study Design
- Not specified
- Arm && Interventions
Group Intervention Description Sigma Posterior Stabilizing Rotating Platform TKA Beaded Poly 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
- Primary Outcome Measures
Name Time Method Range of Motion During Flexion of Deep Knee Bend Activity 10 yrs post-operative In Vivo Linear Knee Kinematics From Fluoroscopy Evaluation During Deep Knee Bend Activity 10 yrs post-operative 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 10 yrs post-operative
- Secondary Outcome Measures
Name Time Method In Vivo Knee Force Values From Fluoroscopy Evaluation During Deep Knee Bend Activity 10 yrs post-operative The intended unit of measure is "times Body Weight" (or xBW), relating to a ratio.
Condyle Contact Stress at Maximum Flexion During Deep Knee Bend Activity 10 yrs post-operative Condyle Contact Area at Maximum Flexion During Deep Knee Bend Activity 10 yrs post-operative
Trial Locations
- Locations (3)
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, United States