In Vivo Determination of 3D Patellofemoral Mechanics

NCT01290627 | Completed Results

• 2 other identifiers: 10035/IIS-000126R011373372
• Study Type: observational
• Target: 30
• Locations: 1 country
• Sites: 4

Brief Summary

This study will analyze the tibio-femoral and patellofemoral (motion) and mechanics (forces) of participants having a normal knee or a total knee arthroplasty (TKA) using one or two different (TKA) devices Low Contract Stress (LCS) Posterior Stabilizing (PS) Rotating Platform (RP) Total Knee Arthroplasty (TKA). All knees will be analyzed using an image matching technique that will convert a two-dimensional (2D) fluoroscopic image into a three-dimensional (3D) image. In conjunction with the fluoroscopic analysis, electromyography (EMG) data, and ground reaction force (GRF) data will all be allow for a complete analysis of the knee joints. These results will help the orthopaedic community better understand knee motion so they can improve testing on existing implants and develop future implants that will further enhance patients' lives.

Conditions

Arthroplasty Replacement Knee; Knee Prosthesis

Outcome Measures

Primary Outcomes (5)

• Patella Flexion With Respect to Femur

  Full extension to maximum flexion. Degrees of flexion analyzed for participants with and without implants.

  Average post-operative time for LCS-PS group was 56 months. Average post-operative time for PS RP group was 55.7 months.

• Patella Rotation With Respect to Femur

  Patellar rotation from full extension to maximum flexion for subjects with and without implants. A positive measurement of patellar rotation refers to positive flexion of the patella about the medial-lateral axis, where the patella component rotates so that the top of the patella rotates toward the femur and the bottom rotates away. Conversely, a negative measurement refers to negative flexion of the patella about this axis, where the patellar component rotates so that the top of the patella moves away from the femur and the bottom moves towards.

  Average post-operative time for LCS-PS group was 56 months. Average post-operative time for PS RP group was 55.7 months.

• Patella Tilt With Respect to Femur

  full extension to maximum flexion for participants with and without implants.

  Average post-operative time for LCS-PS group was 56 months. Average post-operative time for PS RP group was 55.7 months.

• Normalized Medial Patella Contact Point Translation

  full extension to maximum flexion for participants with and without implants. Position of the patellar contact point was determined by locating the closest point to the femur on the patella throughout flexion. There are 2 patello-femoral contact points: a point on the medial aspect of the patella and a point on the lateral aspect of the patella. Throughout flexion, the medial contact point generally moves closer to the top of the patella (hence the positive value for the results). The translation of this contact point is normalized to report a ratio between -1 and 1. In other words, the distance the point has traveled compared to the total height of the patella. For example, if the patella is 8 cm in height and the point travels approximately 2 cm upwards during flexion, the value would be reported as +2/8 = +0.25. Definition of normalized: "multiply (a series, function, or item of data) by a factor that makes the norm or some associated quantity such as an integral equal

  Average post-operative time for LCS-PS group was 56 months. Average post-operative time for PS RP group was 55.7 months.

• Normalized Lateral Patella Contact Point Translation

  full extension to maximum flexion for participants with and without implants. Position of patellar contact point was determined by locating closest point to femur on patella throughout flexion. There are 2 patello-femoral contact points: 1 point on the medial aspect of the patella and 1 point on the lateral aspect of the patella. Throughout flexion, lateral contact point generally moves closer to the top of the patella (hence, the positive value for the results). The translation of this contact point is normalized to report a ratio between -1 and 1. The distance the point has traveled compared to the total height of the patella. For example, if the patella is 8 cm in height and the point travels approximately 2 cm upwards during flexion, the value would be reported as +2/8 = +0.25. Definition of normalized: "multiply (a series, function, or item of data) by a factor that makes the norm or some associated quantity such as an integral equal to a desired value (usually 1)."

  Average post-operative time for LCS-PS group was 56 months. Average post-operative time for PS RP group was 55.7 months.

Study Arms (3)

Knee Prosthesis LCS PS RP TKA

Subjects implanted with DePuy Low Contact Stress (LCS) Poster Stabilizing (PS) Rotating Platform (RP) Total Knee Arthroplasty (TKA)

Device: Subjects implanted with DePuy LCS PS RP TKA

Knee Prosthesis Sigma PS RP TKA

Subjects implanted with a DePuy Sigma Posterior Stabilizing (PS) Rotating Platform (RP) Total Knee Arthroplasty (TKA)

Device: Subjects implanted with DePuy Sigma PS RP TKA

Control

Subjects with normal knees

Interventions

Subjects implanted with DePuy LCS PS RP TKA DEVICE

Subjects implanted with DePuy Low Contact Stress (LCS) Poster Stabilizing (PS) Rotating Platform (RP) Total Knee Arthroplasty (TKA)

Knee Prosthesis LCS PS RP TKA

Subjects implanted with DePuy Sigma PS RP TKA DEVICE

Subjects implanted with a DePuy Sigma Posterior Stabilizing (PS) Rotating Platform (RP) Total Knee Arthroplasty (TKA)

Knee Prosthesis Sigma PS RP TKA

Eligibility Criteria

• Age: 20 Years - 85 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Subjects recruited from patients chosen from practice of Dr.'s Dennis and Haas at Colorado Joint Replacement for implanted knee, having either one of the two kinds of implants specified.

You may qualify if:

• Patients must be at least six months post-operative.
• Potential subjects will have a body weight of less than 250 lbs.
• Candidates must have an AKS score \>70 post-operatively.
• Patients must have passive flexion of at least 100.
• Implanted group must have either an LCS PS RP TKA, having an anatomical patella, or Sigma PS RP TKA; or normal knee group must have normal knee.
• Must be willing to sign both Informed Consent and HIPAA forms.

You may not qualify if:

• Pregnant females.
• Subjects not meeting study requirements.

Sponsors & Collaborators

• The University of Tennessee, Knoxville: lead
• DePuy Orthopaedics: collaborator

Study Sites (4)

Colorado Joint Replacement

Denver, Colorado, 80210, United States

Location

Porter Adventist Hospital

Denver, Colorado, 80210, United States

Location

Perkins Hall

Knoxville, Tennessee, 37996, United States

Location

Science and Engineering Research Facility

Knoxville, Tennessee, 37996, United States

Location

Limitations and Caveats

No adverse effects, events or unexpected risks occurred The sample size per group was small Age of the TKA groups were matched, the age of the normal subjects were not Cartilage thickness for normals had to be assumed as MRIs could not be obtained

Results Point of Contact

• Title: Richard Komistek, Ph. D.
• Organization: The University of Tennessee

rkomiste@utk.edu

86598744159

Study Officials

• Richard D. Komistek, Ph D

  The University of Tennessee

  PRINCIPAL INVESTIGATOR

• Douglas Dennis, MD

  Colorado Joint Replacement, Porter Adventist Hosp

  PRINCIPAL INVESTIGATOR

Publication Agreements

• PI is Sponsor Employee: Yes
• Restrictive Agreement: No

Study Design

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

Study Record Dates

• First Submitted: February 3, 2011
• First Posted: February 7, 2011
• Study Start: February 1, 2011
• Primary Completion: September 1, 2011
• Study Completion: September 1, 2011
• Last Updated: October 29, 2019
• Results First Posted: January 13, 2014

Record last verified: 2019-10

Locations

US (4)