Comparison of Knee Kinematics for Subjects Implanted With Either a ConforMIS or Traditional Knee Implant

NCT ID: NCT01717001

Last Updated: 2023-10-25

Basic Information

• Recruitment Status: COMPLETED
• Total Enrollment: 66 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2012-08-31
• Study Completion Date: 2014-08-31

Brief Summary

A better understanding of knee joint kinematics is important to explain the premature polyethylene wear failures within total knee arthroplasties (TKAs) and to help design a prosthesis that most closely approximates the normal knee. Previously, most experimental studies of knee kinematics have involved cadaveric, in vitro analyses, or have not tested the knee in a weight-bearing mode. Others have used exoskeletal linkages and skin markers that permit error due to undesired motions between markers and the underlying bone. More recently, fluoroscopy has been used to assess in vivo kinematics for subjects having a TKA.

ConforMIS has attempted to follow a clearly different path than the major orthopaedic companies. They have chosen to offer patients a personalized knee implant based off of each patient's femoral and tibial bone geometry. The hypothesis is that these subjects will experience a more normal-like kinematic pattern, eliminating paradoxical anterior sliding during weight-bearing knee flexion. Therefore, the objective for this study is to analyze the in vivo kinematics for 25 patients implanted with a personalized ConforMIS TKA and 25 patients implanted with a traditional TKA design to determine if there are any kinematic differences between these TKA designs.

Detailed Description

Each subject will be asked to perform five activities in one continuous sequence: (1) stand up from a chair, (2) walk up stairs, (3) walk down stairs, (4) level walking, and (5) a deep knee bend. Subjects will be video recorded from the waist down while performing the activities. The speed level of each trial will be based on the comfort level of the patient. The fluoroscopic images will be stored digitally for subsequent analysis on secure servers and workstations at the University of Tennessee.

Conditions

Osteoarthritis

Study Design

• Observational Model Type: CASE_CONTROL
• Study Time Perspective: PROSPECTIVE

Study Groups

ConforMIS

Patients with ConforMIS implants

No interventions assigned to this group

Standard Total Knee Implant

Patients implanted with standard total knee implant

No interventions assigned to this group

Eligibility Criteria

Inclusion Criteria

• At least 6 months post-op with no other surgical procedures conducted within the past 6 months
• Between 40-70 years of age
• Body weight of less than 250lbs
• BMI of less than 38
• Pregnant females will be excluded
• TKA patients will be judged Clinically successful with an American Knee Society score of greater than 90
• Must have 100 degrees post-op passive flexion with no ligamentous laxity or pain
• Participants must be able to walk on level ground without aid of any kind and ascend/descend stairs without assistance.
• All potential subjects will have either a personalized ConforMIS™ TKA or a traditional TKA manufactured by an orthopaedic company other than ConforMIS.
• Patients from the physician's list who do not meet the study requirements will not be considered.
• Patients must be willing to sign the Informed Consent and HIPAA forms to participate in the study.
• Patients must be between 160cm (5'3) and 193cm (6'4) tall.

• Minimum Eligible Age: 40 Years
• Maximum Eligible Age: 70 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Restor3D

INDUSTRY

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Richard D Komistek, PhD

Role: PRINCIPAL_INVESTIGATOR

Univeristy of Tennessee

William Kurtz, MD

Role: PRINCIPAL_INVESTIGATOR

Tennessee Orthopedic Alliance

Locations

University of Tennessee

Knoxville, Tennessee, United States

Tennessee Orthopedic Alliance

Nashville, Tennessee, United States

Countries

United States

Other Identifiers

Komistek 1

Identifier Type: -

Identifier Source: org_study_id