<clinical_study>
  <!-- This xml conforms to an XML Schema at:
    https://clinicaltrials.gov/ct2/html/images/info/public.xsd -->
  <required_header>
    <download_date>ClinicalTrials.gov processed this data on September 20, 2023</download_date>
    <link_text>Link to the current ClinicalTrials.gov record.</link_text>
    <url>https://clinicaltrials.gov/ct2/show/NCT01714492</url>
  </required_header>
  <id_info>
    <org_study_id>11019</org_study_id>
    <secondary_id>R01 1373 424</secondary_id>
    <nct_id>NCT01714492</nct_id>
  </id_info>
  <brief_title>Mechanics Analysis of Patients Having a Sigma Mobile Bearing TKA</brief_title>
  <acronym>Sigma MB TKA</acronym>
  <official_title>In Vivo Mechanics Analysis of Patients Having a Sigma Mobile Bearing TKA</official_title>
  <sponsors>
    <lead_sponsor>
      <agency>The University of Tennessee, Knoxville</agency>
      <agency_class>Other</agency_class>
    </lead_sponsor>
    <collaborator>
      <agency>DePuy Orthopaedics</agency>
      <agency_class>Industry</agency_class>
    </collaborator>
  </sponsors>
  <source>The University of Tennessee, Knoxville</source>
  <oversight_info>
    <has_dmc>No</has_dmc>
  </oversight_info>
  <brief_summary>
    <textblock>
      Utilize previously developed mathematical model to determine in vivo knee mechanics&#xD;
      (kinematics, forces, stresses, areas and sound) for subjects having a Sigma Posterior&#xD;
      Stabilizing (PS) mobile bearing (MB) total knee arthroplasty (TKA). There are several&#xD;
      hypotheses for this study, although the most prominent is: Subjects having a Sigma RP PS TKA&#xD;
      will experience polyethylene bearing rotation at 10 years post-operative, similar to their&#xD;
      previous evaluations at six months, two years and five years.&#xD;
    </textblock>
  </brief_summary>
  <detailed_description>
    <textblock>
      Additional hypotheses:&#xD;
&#xD;
        -  Subjects having a Sigma RP PS TKA will experience full ideal femorotibial contact&#xD;
           mechanics.&#xD;
&#xD;
        -  Subjects having a Sigma RP PS TKA will experience optimal cam/post mechanics.&#xD;
&#xD;
        -  Subjects having a Sigma RP PS TKA will experience continuous axial rotation in deep&#xD;
           flexion.&#xD;
&#xD;
        -  Subjects having a Sigma RP PS TKA will experience optimal distribution of tibio-femoral&#xD;
           and cam/post contact forces over a broad area on the post.&#xD;
&#xD;
        -  Subjects having a Sigma RP PS TKA will experience a smooth transition of the cam on the&#xD;
           post, not an abrupt slide as seen with fixed bearing PS TKA.&#xD;
&#xD;
        -  The use of the sound sensors will detect cam/post contact mechanics under in vivo&#xD;
           conditions.&#xD;
    </textblock>
  </detailed_description>
  <overall_status>Completed</overall_status>
  <start_date>April 2012</start_date>
  <completion_date type="Actual">November 2012</completion_date>
  <primary_completion_date type="Actual">November 2012</primary_completion_date>
  <study_type>Observational</study_type>
  <has_expanded_access>No</has_expanded_access>
  <study_design_info>
    <observational_model>Cohort</observational_model>
    <time_perspective>Cross-Sectional</time_perspective>
  </study_design_info>
  <primary_outcome>
    <measure>In Vivo Linear Knee Kinematics From Fluoroscopy Evaluation During Deep Knee Bend Activity</measure>
    <time_frame>10 yrs post-operative</time_frame>
    <description>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.</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Femoral Axial Rotation With Respect to the Tibia During Deep Knee Bend Activity</measure>
    <time_frame>10 yrs post-operative</time_frame>
  </primary_outcome>
  <primary_outcome>
    <measure>Range of Motion During Flexion of Deep Knee Bend Activity</measure>
    <time_frame>10 yrs post-operative</time_frame>
  </primary_outcome>
  <secondary_outcome>
    <measure>In Vivo Knee Force Values From Fluoroscopy Evaluation During Deep Knee Bend Activity</measure>
    <time_frame>10 yrs post-operative</time_frame>
    <description>The intended unit of measure is &quot;times Body Weight&quot; (or xBW), relating to a ratio.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Condyle Contact Area at Maximum Flexion During Deep Knee Bend Activity</measure>
    <time_frame>10 yrs post-operative</time_frame>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Condyle Contact Stress at Maximum Flexion During Deep Knee Bend Activity</measure>
    <time_frame>10 yrs post-operative</time_frame>
  </secondary_outcome>
  <number_of_groups>1</number_of_groups>
  <enrollment type="Actual">8</enrollment>
  <condition>Knee Prosthesis</condition>
  <condition>Knee Replacement Arthroplasty</condition>
  <arm_group>
    <arm_group_label>Sigma Posterior Stabilizing Rotating Platform TKA Beaded Poly</arm_group_label>
    <description>subjects implanted with the Sigma Posterior Stabilizing Rotating Platform TKA including a polyethylene insert with 4 beads</description>
  </arm_group>
  <intervention>
    <intervention_type>Device</intervention_type>
    <intervention_name>Sigma Posterior Stabilizing Rotating Platform TKA Beaded Poly</intervention_name>
    <description>Sigma PS RP TKA including a polyethylene insert with 4 beads</description>
    <arm_group_label>Sigma Posterior Stabilizing Rotating Platform TKA Beaded Poly</arm_group_label>
  </intervention>
  <eligibility>
    <study_pop>
      <textblock>
        Patients are eight mobile bearing subjects that were implanted over 10 years ago with a&#xD;
        custom polyethylene insert that has four beads rigidly inserted into the polyethylene&#xD;
        component.&#xD;
      </textblock>
    </study_pop>
    <sampling_method>Probability Sample</sampling_method>
    <criteria>
      <textblock>
        Inclusion Criteria:&#xD;
&#xD;
          -  At least six months post-operative&#xD;
&#xD;
          -  Between 40-85 years of age&#xD;
&#xD;
          -  Have a body weight of less than 250 lbs.&#xD;
&#xD;
          -  Judged clinically successful with a AKS greater than 90&#xD;
&#xD;
          -  Have the DePuy Sigma mobile bearing TKA&#xD;
&#xD;
          -  Good-to-excellent post-operative passive flexion&#xD;
&#xD;
          -  Must be willing to sign the IC and HIPAA forms.&#xD;
&#xD;
        Exclusion Criteria:&#xD;
&#xD;
          -  Pregnant females&#xD;
&#xD;
          -  Those not willing to sign the IC and HIPAA forms&#xD;
      </textblock>
    </criteria>
    <gender>All</gender>
    <minimum_age>40 Years</minimum_age>
    <maximum_age>85 Years</maximum_age>
    <healthy_volunteers>No</healthy_volunteers>
  </eligibility>
  <overall_official>
    <last_name>Richard D Komistek, Ph. D.</last_name>
    <role>Principal Investigator</role>
    <affiliation>The University of Tennessee</affiliation>
  </overall_official>
  <overall_official>
    <last_name>Dennis A Douglas, MD</last_name>
    <role>Principal Investigator</role>
    <affiliation>Colorado Joint Replacement</affiliation>
  </overall_official>
  <location>
    <facility>
      <name>Porter Adventist Hospital, Colorado Joint Replacement</name>
      <address>
        <city>Denver</city>
        <state>Colorado</state>
        <zip>80210</zip>
        <country>United States</country>
      </address>
    </facility>
  </location>
  <location>
    <facility>
      <name>Perkins Hall, The University of Tennessee</name>
      <address>
        <city>Knoxville</city>
        <state>Tennessee</state>
        <zip>37996</zip>
        <country>United States</country>
      </address>
    </facility>
  </location>
  <location>
    <facility>
      <name>Science and Engineering Research Facility, The University of Tennessee</name>
      <address>
        <city>Knoxville</city>
        <state>Tennessee</state>
        <zip>37996</zip>
        <country>United States</country>
      </address>
    </facility>
  </location>
  <location_countries>
    <country>United States</country>
  </location_countries>
  <verification_date>October 2019</verification_date>
  <study_first_submitted>October 23, 2012</study_first_submitted>
  <study_first_submitted_qc>October 25, 2012</study_first_submitted_qc>
  <study_first_posted type="Estimate">October 26, 2012</study_first_posted>
  <results_first_submitted>May 23, 2013</results_first_submitted>
  <results_first_submitted_qc>January 21, 2014</results_first_submitted_qc>
  <results_first_posted type="Estimate">February 17, 2014</results_first_posted>
  <last_update_submitted>October 8, 2019</last_update_submitted>
  <last_update_submitted_qc>October 8, 2019</last_update_submitted_qc>
  <last_update_posted type="Actual">October 10, 2019</last_update_posted>
  <responsible_party>
    <responsible_party_type>Principal Investigator</responsible_party_type>
    <investigator_affiliation>The University of Tennessee, Knoxville</investigator_affiliation>
    <investigator_full_name>Richard Komistek</investigator_full_name>
    <investigator_title>Principal Investigator</investigator_title>
  </responsible_party>
  <keyword>Total Knee Arthroplasty (TKA)</keyword>
  <keyword>in vivo mechanics</keyword>
  <keyword>kinematics</keyword>
  <keyword>fluoroscopy</keyword>

  <clinical_results>

    <participant_flow>
      <recruitment_details>hospital, medical clinic</recruitment_details>
      <group_list>
        <group group_id="P1">
          <title>Sigma Posterior Stabilizing Rotating Platform TKA Beaded Poly</title>
          <description>subjects implanted with the Sigma Posterior Stabilizing Rotating Platform TKA including a polyethylene insert with 4 beads that allow for determination of polyethylene rotation.</description>
        </group>
      </group_list>
      <period_list>
        <period>
          <title>Overall Study</title>
          <milestone_list>
            <milestone>
              <title>STARTED</title>
              <participants_list>
                <participants group_id="P1" count="8"/>
              </participants_list>
            </milestone>
            <milestone>
              <title>COMPLETED</title>
              <participants_list>
                <participants group_id="P1" count="8"/>
              </participants_list>
            </milestone>
            <milestone>
              <title>NOT COMPLETED</title>
              <participants_list>
                <participants group_id="P1" count="0"/>
              </participants_list>
            </milestone>
          </milestone_list>
        </period>
      </period_list>
    </participant_flow>

    <baseline>
      <group_list>
        <group group_id="B1">
          <title>Sigma Posterior Stabilizing Rotating Platform TKA Beaded Poly</title>
          <description>subjects implanted with the Sigma Posterior Stabilizing Rotating Platform TKA including a polyethylene insert with 4 beads that allow for determination of polyethylene rotation.</description>
        </group>
      </group_list>
      <analyzed_list>
        <analyzed>
          <units>Participants</units>
          <scope>Overall</scope>
          <count_list>
            <count group_id="B1" value="8"/>
          </count_list>
        </analyzed>
      </analyzed_list>
      <measure_list>
        <measure>
          <title>Age</title>
          <units>Participants</units>
          <param>Count of Participants</param>
          <class_list>
            <class>
              <category_list>
                <category>
                  <title>&lt;=18 years</title>
                  <measurement_list>
                    <measurement group_id="B1" value="0"/>
                  </measurement_list>
                </category>
                <category>
                  <title>Between 18 and 65 years</title>
                  <measurement_list>
                    <measurement group_id="B1" value="1"/>
                  </measurement_list>
                </category>
                <category>
                  <title>&gt;=65 years</title>
                  <measurement_list>
                    <measurement group_id="B1" value="7"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
        <measure>
          <title>Age</title>
          <units>years</units>
          <param>Mean</param>
          <dispersion>Standard Deviation</dispersion>
          <class_list>
            <class>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="B1" value="74" spread="8.6"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
        <measure>
          <title>Sex: Female, Male</title>
          <units>Participants</units>
          <param>Count of Participants</param>
          <class_list>
            <class>
              <category_list>
                <category>
                  <title>Female</title>
                  <measurement_list>
                    <measurement group_id="B1" value="6"/>
                  </measurement_list>
                </category>
                <category>
                  <title>Male</title>
                  <measurement_list>
                    <measurement group_id="B1" value="2"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
        <measure>
          <title>Region of Enrollment</title>
          <units>participants</units>
          <param>Number</param>
          <class_list>
            <class>
              <title>United States</title>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="B1" value="8"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </measure_list>
    </baseline>

    <outcome_list>
      <outcome>
        <type>Primary</type>
        <title>In Vivo Linear Knee Kinematics From Fluoroscopy Evaluation During Deep Knee Bend Activity</title>
        <description>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.</description>
        <time_frame>10 yrs post-operative</time_frame>
        <population>Subjects implanted with the Sigma Posterior Stabilizing Rotating Platform TKA including a polyethylene insert with 4 beads that allow for determination of polyethylene rotation.</population>
        <group_list>
          <group group_id="O1">
            <title>In Vivo Knee Kinematics From Fluoroscopy Evaluation During Dee</title>
            <description>subjects implanted with the Sigma Posterior Stabilizing Rotating Platform TKA including a polyethylene insert with 4 beads that allow for determination of polyethylene rotation.</description>
          </group>
        </group_list>
        <measure>
          <title>In Vivo Linear Knee Kinematics From Fluoroscopy Evaluation During Deep Knee Bend Activity</title>
          <description>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.</description>
          <population>Subjects implanted with the Sigma Posterior Stabilizing Rotating Platform TKA including a polyethylene insert with 4 beads that allow for determination of polyethylene rotation.</population>
          <units>mm</units>
          <param>Mean</param>
          <dispersion>Standard Deviation</dispersion>
          <units_analyzed>Implants</units_analyzed>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="8"/>
              </count_list>
            </analyzed>
            <analyzed>
              <units>Implants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="8"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>Lateral Anterior Posterior Deep Knee Bend</title>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="-4.1" spread="2.4"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Medial Anterior Posterior Deep Knee Bend</title>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.2" spread="2.8"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Secondary</type>
        <title>In Vivo Knee Force Values From Fluoroscopy Evaluation During Deep Knee Bend Activity</title>
        <description>The intended unit of measure is &quot;times Body Weight&quot; (or xBW), relating to a ratio.</description>
        <time_frame>10 yrs post-operative</time_frame>
        <population>Subjects implanted with the Sigma Posterior Stabilizing Rotating Platform TKA including a polyethylene insert with 4 beads that allow for determination of polyethylene rotation</population>
        <group_list>
          <group group_id="O1">
            <title>Sigma Posterior Stabilizing Rotating Platform TKA Beaded Poly</title>
            <description>subjects implanted with the Sigma Posterior Stabilizing Rotating Platform TKA including a polyethylene insert with 4 beads that allow for determination of polyethylene rotation.</description>
          </group>
        </group_list>
        <measure>
          <title>In Vivo Knee Force Values From Fluoroscopy Evaluation During Deep Knee Bend Activity</title>
          <description>The intended unit of measure is &quot;times Body Weight&quot; (or xBW), relating to a ratio.</description>
          <population>Subjects implanted with the Sigma Posterior Stabilizing Rotating Platform TKA including a polyethylene insert with 4 beads that allow for determination of polyethylene rotation</population>
          <units>times body weight</units>
          <param>Mean</param>
          <dispersion>Standard Deviation</dispersion>
          <units_analyzed>Implants</units_analyzed>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="8"/>
              </count_list>
            </analyzed>
            <analyzed>
              <units>Implants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="8"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>Medial Condyle Knee Force at Maximum Flexion</title>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.57" spread="0.53"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Lateral Condyle Knee Force at Maximum Flexion</title>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.39" spread="0.36"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Primary</type>
        <title>Femoral Axial Rotation With Respect to the Tibia During Deep Knee Bend Activity</title>
        <time_frame>10 yrs post-operative</time_frame>
        <group_list>
          <group group_id="O1">
            <title>In Vivo Knee Kinematics From Fluoroscopy Evaluation During Dee</title>
            <description>subjects implanted with the Sigma Posterior Stabilizing Rotating Platform TKA including a polyethylene insert with 4 beads that allow for determination of polyethylene rotation.</description>
          </group>
        </group_list>
        <measure>
          <title>Femoral Axial Rotation With Respect to the Tibia During Deep Knee Bend Activity</title>
          <units>degrees</units>
          <param>Mean</param>
          <dispersion>Standard Deviation</dispersion>
          <units_analyzed>Implants</units_analyzed>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="8"/>
              </count_list>
            </analyzed>
            <analyzed>
              <units>Implants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="8"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="6.1" spread="5.8"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Primary</type>
        <title>Range of Motion During Flexion of Deep Knee Bend Activity</title>
        <time_frame>10 yrs post-operative</time_frame>
        <group_list>
          <group group_id="O1">
            <title>In Vivo Knee Kinematics From Fluoroscopy Evaluation During Dee</title>
            <description>subjects implanted with the Sigma Posterior Stabilizing Rotating Platform TKA including a polyethylene insert with 4 beads that allow for determination of polyethylene rotation.</description>
          </group>
        </group_list>
        <measure>
          <title>Range of Motion During Flexion of Deep Knee Bend Activity</title>
          <units>degrees</units>
          <param>Mean</param>
          <dispersion>Standard Deviation</dispersion>
          <units_analyzed>Implants</units_analyzed>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="8"/>
              </count_list>
            </analyzed>
            <analyzed>
              <units>Implants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="8"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="103" spread="11.2"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Secondary</type>
        <title>Condyle Contact Area at Maximum Flexion During Deep Knee Bend Activity</title>
        <time_frame>10 yrs post-operative</time_frame>
        <group_list>
          <group group_id="O1">
            <title>In Vivo Knee Kinematics From Fluoroscopy Evaluation During Dee</title>
            <description>subjects implanted with the Sigma Posterior Stabilizing Rotating Platform TKA including a polyethylene insert with 4 beads that allow for determination of polyethylene rotation.</description>
          </group>
        </group_list>
        <measure>
          <title>Condyle Contact Area at Maximum Flexion During Deep Knee Bend Activity</title>
          <units>mm^2</units>
          <param>Mean</param>
          <dispersion>Standard Deviation</dispersion>
          <units_analyzed>Implants</units_analyzed>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="8"/>
              </count_list>
            </analyzed>
            <analyzed>
              <units>Implants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="8"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>Medial</title>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="109.16" spread="2.82"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Lateral</title>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="104.78" spread="21.22"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Secondary</type>
        <title>Condyle Contact Stress at Maximum Flexion During Deep Knee Bend Activity</title>
        <time_frame>10 yrs post-operative</time_frame>
        <group_list>
          <group group_id="O1">
            <title>In Vivo Knee Kinematics From Fluoroscopy Evaluation During Dee</title>
            <description>subjects implanted with the Sigma Posterior Stabilizing Rotating Platform TKA including a polyethylene insert with 4 beads that allow for determination of polyethylene rotation.</description>
          </group>
        </group_list>
        <measure>
          <title>Condyle Contact Stress at Maximum Flexion During Deep Knee Bend Activity</title>
          <units>MPa</units>
          <param>Mean</param>
          <dispersion>Standard Deviation</dispersion>
          <units_analyzed>Implants</units_analyzed>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="8"/>
              </count_list>
            </analyzed>
            <analyzed>
              <units>Implants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="8"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>Average Medial Condyle Contact Stress</title>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="10.66" spread="1.75"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Average Lateral Condyle Contact Stress</title>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="10.05" spread="1.45"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
    </outcome_list>

    <reported_events>
      <desc>There were no adverse effects or events encountered for any subjects for this study.</desc>
      <group_list>
        <group group_id="E1">
          <title>Sigma Posterior Stabilizing Rotating Platform TKA Beaded Poly</title>
          <description>subjects implanted with the Sigma Posterior Stabilizing Rotating Platform TKA including a polyethylene insert with 4 beads that allow for determination of polyethylene rotation.</description>
        </group>
      </group_list>
      <serious_events>
        <category_list>
          <category>
            <title>Total</title>
            <event_list>
              <event>
                <sub_title>Total, serious adverse events</sub_title>
                <counts group_id="E1" subjects_affected="0" subjects_at_risk="8"/>
              </event>
            </event_list>
          </category>
        </category_list>
      </serious_events>
      <other_events>
        <frequency_threshold>0</frequency_threshold>
        <category_list>
          <category>
            <title>Total</title>
            <event_list>
              <event>
                <sub_title>Total, other adverse events</sub_title>
                <counts group_id="E1" subjects_affected="0" subjects_at_risk="8"/>
              </event>
            </event_list>
          </category>
        </category_list>
      </other_events>
    </reported_events>

    <certain_agreements>
      <pi_employee>All Principal Investigators ARE employed by the organization sponsoring the study.</pi_employee>
      <restrictive_agreement>There is NOT an agreement between Principal Investigators and the Sponsor (or its agents) that restricts the PI's rights to discuss or publish trial results after the trial is completed. </restrictive_agreement>
    </certain_agreements>
    <limitations_and_caveats>Small study population; only one specific type of mobile bearing implant was analyzed; no definitive way to quantitatively measure level of wear on various implants to determine if there was any influence on the kinematic performance.</limitations_and_caveats>
    <point_of_contact>
      <name_or_title>Richard Komistek, Ph. D.</name_or_title>
      <organization>The University of Tennessee</organization>
      <phone>8659744159</phone>
      <email>rkomiste@utk.edu</email>
    </point_of_contact>
  </clinical_results>
</clinical_study>


download date: ClinicalTrials.gov processed this data on September 20, 2023
link text: Link to the current ClinicalTrials.gov record.
url: https://clinicaltrials.gov/ct2/show/NCT01714492
org study id: 11019
secondary id: R01 1373 424
nct id: NCT01714492
lead sponsor: 
collaborator: 
has dmc: No
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.
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.
observational model: Cohort
time perspective: Cross-Sectional
measure: In Vivo Linear Knee Kinematics From Fluoroscopy Evaluation During Deep Knee Bend Activity
time frame: 10 yrs post-operative
description: 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.
measure: Femoral Axial Rotation With Respect to the Tibia During Deep Knee Bend Activity
time frame: 10 yrs post-operative
measure: Range of Motion During Flexion of Deep Knee Bend Activity
time frame: 10 yrs post-operative
measure: In Vivo Knee Force Values From Fluoroscopy Evaluation During Deep Knee Bend Activity
time frame: 10 yrs post-operative
description: The intended unit of measure is "times Body Weight" (or xBW), relating to a ratio.
measure: Condyle Contact Area at Maximum Flexion During Deep Knee Bend Activity
time frame: 10 yrs post-operative
measure: Condyle Contact Stress at Maximum Flexion During Deep Knee Bend Activity
time frame: 10 yrs post-operative
arm group label: Sigma Posterior Stabilizing Rotating Platform TKA Beaded Poly
description: subjects implanted with the Sigma Posterior Stabilizing Rotating Platform TKA including a polyethylene insert with 4 beads
intervention type: Device
intervention name: Sigma Posterior Stabilizing Rotating Platform TKA Beaded Poly
description: Sigma PS RP TKA including a polyethylene insert with 4 beads
arm group label: Sigma Posterior Stabilizing Rotating Platform TKA Beaded Poly
study pop: 
sampling method: Probability Sample
criteria: 
gender: All
minimum age: 40 Years
maximum age: 85 Years
healthy volunteers: No
last name: Richard D Komistek, Ph. D.
role: Principal Investigator
affiliation: The University of Tennessee
last name: Dennis A Douglas, MD
role: Principal Investigator
affiliation: Colorado Joint Replacement
facility: 
facility: 
facility: 
country: United States
responsible party type: Principal Investigator
investigator affiliation: The University of Tennessee, Knoxville
investigator full name: Richard Komistek
investigator title: Principal Investigator
participant flow: 
baseline: 
outcome list: 
reported events: 
certain agreements: 
limitations and caveats: Small study population; only one specific type of mobile bearing implant was analyzed; no definitive way to quantitatively measure level of wear on various implants to determine if there was any influence on the kinematic performance.
point of contact: 