<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/NCT02201966</url>
  </required_header>
  <id_info>
    <org_study_id>IRB14-00229</org_study_id>
    <nct_id>NCT02201966</nct_id>
  </id_info>
  <brief_title>Regional Interdependence of the Shoulders and Hips in Gymnasts With Low Back Pain</brief_title>
  <official_title>Regional Interdependence of the Shoulders and Hips in Gymnasts With Low Back Pain</official_title>
  <sponsors>
    <lead_sponsor>
      <agency>Nationwide Children's Hospital</agency>
      <agency_class>Other</agency_class>
    </lead_sponsor>
  </sponsors>
  <source>Nationwide Children's Hospital</source>
  <oversight_info>
    <has_dmc>No</has_dmc>
  </oversight_info>
  <brief_summary>
    <textblock>
      Low back pain is a common condition in children who perform gymnastics. Commonly, the injury&#xD;
      is not the result of a specific injury, but is a stress injury to the lumbar spine. Regional&#xD;
      interdependence is a theory that suggests when adjacent joints and muscles are not working&#xD;
      properly increased stress is placed on a particular joint. This theory would suggest that if&#xD;
      a patient did not have enough hip extension to perform a back bend increased motion would&#xD;
      occur in the lumbar spine allowing the gymnast to complete the technique. Currently, no&#xD;
      research links impairments in other joints to low back pain in gymnasts.&#xD;
&#xD;
      This is a cross sectional study assessing the relationship between gymnast with back pain and&#xD;
      flexibility and strength of the shoulder and hip joints. Investigators will travel to a local&#xD;
      gymnastics training centers and assess the gymnasts' strength and flexibility of the the hips&#xD;
      and shoulders. The gymnast will also fill our a questionnaire assessing if they have had back&#xD;
      pain in the past month and how much has it limited their ability to participate in&#xD;
      gymnastics. Investigators will be blinded to the results of this survey.&#xD;
&#xD;
      The goal of this research study is to see if there are any link between strength and&#xD;
      flexibility of the hips, and shoulders and gymnasts with low back pain. The investigators&#xD;
      hypothesize that gymnasts who demonstrates impairments in strength and flexibility of the&#xD;
      hips, or shoulders will be more likely to have complaints of low back pain.&#xD;
    </textblock>
  </brief_summary>
  <detailed_description>
    <textblock>
      Female gymnasts will fill out a survey prior having their strength and flexibility tested.&#xD;
      The investigators will be blinded to the results of the survey.&#xD;
&#xD;
      The questionaire asked the gymnasts several questions:&#xD;
&#xD;
        1. Age&#xD;
&#xD;
        2. Years in Gymnastics&#xD;
&#xD;
        3. At what level did you last compete?&#xD;
&#xD;
        4. On average how many hours per week do you participate in gymnastics?&#xD;
&#xD;
        5. Have you had any back pain in the past month that has affected your ability to&#xD;
           participate in gymnastics?&#xD;
&#xD;
        6. If you answered yes to the last question: please rate your ability to participate in&#xD;
           gymnastics with back pain?(0 represents unable to perform gymnastics and 100 represents&#xD;
           no difficulty participating in gymnastics&#xD;
&#xD;
      After the gymnast complete the survey the investigators will assess the flexibility and&#xD;
      strength of their shoulder and hip muscles. Investigators will be blinded to survey results.&#xD;
      Evaluation measures will be performed in a randomized manner. Subjects will randomly perform&#xD;
      shoulder or hip testing first (determined by flip of coin). Flexibility and strength testing&#xD;
      will also be determined randomly (determined by flip of coin).&#xD;
&#xD;
      Evaluation measures&#xD;
&#xD;
      Shoulder Flexibility Passive Motion test:&#xD;
&#xD;
        -  Prior to shoulder flexibility testing, the gymnast's arm length is measured from the tip&#xD;
           of the acromion process to a ½ inch wooden dowel grasped by both hands while holding&#xD;
           their shoulders flexed to 90 degrees.&#xD;
&#xD;
        -  For testing, the gymnast lies prone on a firm floor with their chin and nose touching&#xD;
           the floor.&#xD;
&#xD;
        -  Both arms are held parallel to the body with the shoulders flexed to 180 degrees.&#xD;
&#xD;
        -  The gymnast grasps the ½ inch dowel with and overhand grip and the tips of her thumbs&#xD;
           are touching.&#xD;
&#xD;
        -  The evaluator maximally flexes the gymnasts shoulders while maintaining wrist in neutral&#xD;
           position, elbows extended and their nose and chin in contact with the floor.&#xD;
&#xD;
        -  Once the gymnast's arms are raised to maximum height, the distance from the dowel, where&#xD;
           the thumbs are touching, to the floor is measured and recorded to the nearest ½&#xD;
           centimeter using a rigid measuring stick.&#xD;
&#xD;
        -  The Shoulder flexibility Passive Motion test raw score is calculated my dividing the&#xD;
           dowel height attained by the length of the gymnast's arm.&#xD;
&#xD;
      Shoulder Flexibility Active Motion test:&#xD;
&#xD;
        -  Prior to shoulder flexibility testing, the gymnast's arm length is measured from the tip&#xD;
           of the acromion process to a ½ inch wooden dowel grasped by both hands while holding&#xD;
           their shoulders flexed to 90 degrees.&#xD;
&#xD;
        -  For testing, the gymnast lies prone on a firm floor with their chin and nose touching&#xD;
           the floor.&#xD;
&#xD;
        -  Both arms are held parallel to the body with the shoulders flexed to 180 degrees.&#xD;
&#xD;
        -  The gymnast grasps the ½ inch dowel with and overhand grip and the tips of her thumbs&#xD;
           are touching.&#xD;
&#xD;
        -  The gymnast is asked to maximally flex their shoulders while maintaining wrist in&#xD;
           neutral position, elbows extended and their nose and chin in contact with the floor.&#xD;
&#xD;
        -  Once the gymnast has raised their arms to the maximum height, the distance from the&#xD;
           dowel, where the thumbs are touching, to the floor is measured and recorded to the&#xD;
           nearest ½ centimeter using a rigid measuring stick.&#xD;
&#xD;
        -  The Shoulder flexibility test raw score is calculated my dividing the dowel height&#xD;
           attained by the length of the gymnast's arm.&#xD;
&#xD;
      Hip Extension Flexibility test (Thomas test):&#xD;
&#xD;
        -  Prior to hip extension flexibility testing, the gymnast lays flat on the examination&#xD;
           table with legs extended. The examiner places the digital inclinometer on the anterior&#xD;
           portion of the mid-thigh and zeros the inclinometer. The examiner marks the gymnast's&#xD;
           skin at the distal most portion of the inclinometer in contact with the gymnast.&#xD;
&#xD;
        -  Hip extension flexibility will be measured by using the modified Thomas test.&#xD;
&#xD;
        -  The gymnast is instructed to sit as close to the edge of the examination table as&#xD;
           possible.&#xD;
&#xD;
        -  The gymnast supports their contralateral thigh with their arms and, with the assistance&#xD;
           of the examiner, slowly rolls backward onto the table.&#xD;
&#xD;
        -  The contralateral hip is flexed to the point that the gymnast's lumbar lordosis is&#xD;
           flattened, and the right limb is allowed to hang unsupported off the table.&#xD;
&#xD;
        -  The examiner palpates the lumbar spine to confirm that it remains in contact with the&#xD;
           table.&#xD;
&#xD;
        -  Thigh position is also monitored to prevent abduction of the thigh.&#xD;
&#xD;
        -  When the final test position is achieved the examiner places the inclinometer on the&#xD;
           gymnast's anterior thigh in line made prior to testing.&#xD;
&#xD;
        -  0 degrees indicates the gymnast's thigh is parallel to the horizon. If the thigh was&#xD;
           above horizontal the number from the digital inclinometer will be read as negative. If&#xD;
           the thigh is below horizontal the number will be positive.&#xD;
&#xD;
      Dynamometer Testing:&#xD;
&#xD;
      After having received standardized instructions, subjects will perform a series of&#xD;
      familiarization trials consisting of three submaximal contractions per side. Then maximal&#xD;
      voluntary contraction strength will be measured. The side tested first will be randomized&#xD;
      within each test session. All maximal voluntary contraction strength data provided by the&#xD;
      dynamometer (in kilograms) will be normalized to body weight.&#xD;
&#xD;
      Shoulder Flexion Strength test:&#xD;
&#xD;
        -  Strength testing will be performed with hand held dynamometer stabilized by the&#xD;
           examiner.&#xD;
&#xD;
        -  For testing, the gymnast lies prone on a firm floor with their chin and nose touching&#xD;
           the floor.&#xD;
&#xD;
        -  Both arms are held parallel to the body with the shoulders flexed to 180 degrees.&#xD;
&#xD;
        -  The gymnast grasps the ½ inch dowel with and overhand grip and the tips of her thumbs&#xD;
           are touching.&#xD;
&#xD;
        -  The dynamometer pad will be will located on the ½ inch dowel where the gymnasts thumbs&#xD;
           meet.&#xD;
&#xD;
        -  The gymnast is asked to maximally flex their shoulders pressing the dowel into the&#xD;
           dynamometer pad as hard as they can while maintaining wrist in neutral position, elbows&#xD;
           extended and their nose and chin in contact with the floor.&#xD;
&#xD;
        -  Two to three maximal voluntary contraction trials will be permitted. A third trial is&#xD;
           completed only if the difference between the first two maximal voluntary contractions is&#xD;
           &gt;10%.&#xD;
&#xD;
        -  The duration of these contractions will be 5 seconds, and thirty seconds of rest will be&#xD;
           given between trials.&#xD;
&#xD;
        -  If gymnast is unable to actively flex shoulders to 180 degrees the strength test will be&#xD;
           scored as 0.&#xD;
&#xD;
      Isometric maximal voluntary contraction strength of the hip muscles will be measured with a&#xD;
      portable dynamometer fixed to a custom made frame. The custom-made frame is firmly fixed to a&#xD;
      physical therapy treatment table with use of screw clamps. The frame consisted of two&#xD;
      vertical bars and 1 horizontal bar attached to the vertical bars so as to be perpendicular to&#xD;
      the extremities. The dynamometer is fixed to the horizontal bar so as the testing pad can be&#xD;
      positioned properly for testing.&#xD;
&#xD;
      .&#xD;
&#xD;
      Hip Extension Strength Dynamometer Test:&#xD;
&#xD;
        -  Gymnast is in prone position on examination table with tested leg knee fully extended.&#xD;
           Tested hip is in 5 degrees of extension with the knee in full extension.&#xD;
&#xD;
        -  The dynamometer is fixed using the custom made frame&#xD;
&#xD;
        -  The center of the dynamometer pad will be on the posterior aspect of the calcaneus&#xD;
&#xD;
        -  Gymnast is told to stabilize themselves by holding onto the examination table&#xD;
&#xD;
        -  Gymnasts is instructed to push as hard as they can against the dynamometer testing pad.&#xD;
&#xD;
        -  Two to three maximal voluntary contraction trials will be permitted. A third trial is&#xD;
           completed only if the difference between the first two maximal voluntary contractions is&#xD;
           &gt;10%.&#xD;
&#xD;
        -  The duration of these contractions will be 5 seconds, and thirty seconds of rest will be&#xD;
           given between trials.&#xD;
&#xD;
      Hip Abduction Strength Dynamometer test:&#xD;
&#xD;
        -  Gymnast is in sidelying position on examination table with tested leg knee fully&#xD;
           extended.&#xD;
&#xD;
        -  The contralateral hip and knee joints will be positioned at approximately 30 degrees of&#xD;
           flexion for stability and comfort.&#xD;
&#xD;
        -  Tested hip is in 10 degrees of abduction with the knee in full extension.&#xD;
&#xD;
           •. The center of the dynamometer pad will be located 5 cm proximal to the lateral&#xD;
           femoral condyle.&#xD;
&#xD;
        -  Gymnast is told to stabilize themselves by holding onto the examination table.&#xD;
&#xD;
        -  Gymnast is instructed to push as hard as they can against the dynamometer testing pad.&#xD;
&#xD;
        -  The examiner will inspect the whole body position during the maximal voluntary&#xD;
           contraction trials to ensure minimal compensation from pelvic rotation and flexion and&#xD;
           rotation about the hip. If the examiner judges too much compensation, that test will not&#xD;
           be recorded and the subject will be reinstructed in proper testing form.&#xD;
&#xD;
        -  Two to three maximal voluntary contraction trials will be permitted. A third trial is&#xD;
           completed only if the difference between the first two maximal voluntary contractions is&#xD;
           &gt;10%.&#xD;
&#xD;
        -  The duration of these contractions will be 5 seconds, and thirty seconds of rest will be&#xD;
           given between trials.&#xD;
    </textblock>
  </detailed_description>
  <overall_status>Withdrawn</overall_status>
  <start_date>August 2014</start_date>
  <completion_date type="Anticipated">December 2015</completion_date>
  <primary_completion_date type="Anticipated">August 2015</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>Presence of low back pain in past month</measure>
    <time_frame>Baseline</time_frame>
    <description>Presence of significant low back pain that has affected gymnastics ability at time of evaluation</description>
  </primary_outcome>
  <number_of_groups>2</number_of_groups>
  <enrollment type="Actual">0</enrollment>
  <condition>Low Back Pain</condition>
  <arm_group>
    <arm_group_label>Female gymnasts with low back pain</arm_group_label>
    <description>Subset of competitive female gymnasts who report significant low back pain that affects their ability to perform gymnastics.</description>
  </arm_group>
  <arm_group>
    <arm_group_label>Female gymnasts without low back pain</arm_group_label>
    <description>Subset of competitive female gymnasts who deny significant low back pain that affects their ability to perform gymnastics.</description>
  </arm_group>
  <eligibility>
    <study_pop>
      <textblock>
        Competitive female gymnasts. Females who perform gymnastics at local gymnastics training&#xD;
        centers.&#xD;
      </textblock>
    </study_pop>
    <sampling_method>Non-Probability Sample</sampling_method>
    <criteria>
      <textblock>
        Inclusion Criteria:&#xD;
&#xD;
          -  At least 7 years old&#xD;
&#xD;
          -  Level 5 or higher gymnast&#xD;
&#xD;
          -  Female&#xD;
&#xD;
        Exclusion Criteria:&#xD;
&#xD;
          -  Patient with a injury to the shoulder, or hips that prevents them from performing&#xD;
             gymnastics.&#xD;
&#xD;
          -  Patients who are unable to follow directions.&#xD;
      </textblock>
    </criteria>
    <gender>Female</gender>
    <minimum_age>7 Years</minimum_age>
    <maximum_age>N/A</maximum_age>
    <healthy_volunteers>Accepts Healthy Volunteers</healthy_volunteers>
  </eligibility>
  <overall_official>
    <last_name>Mitchell C Selhorst, DPT</last_name>
    <role>Principal Investigator</role>
    <affiliation>Nationwide Childrens Hospital</affiliation>
  </overall_official>
  <location>
    <facility>
      <name>Buckeye Gymnastics</name>
      <address>
        <city>Powell</city>
        <state>Ohio</state>
        <zip>43065</zip>
        <country>United States</country>
      </address>
    </facility>
  </location>
  <location_countries>
    <country>United States</country>
  </location_countries>
  <reference>
    <citation>Thorborg K, Petersen J, Magnusson SP, Holmich P. Clinical assessment of hip strength using a hand-held dynamometer is reliable. Scand J Med Sci Sports. 2010 Jun;20(3):493-501. doi: 10.1111/j.1600-0838.2009.00958.x. Epub 2009 Jun 23.</citation>
    <PMID>19558384</PMID>
  </reference>
  <reference>
    <citation>Sleeper MD, Kenyon LK, Casey E. Measuring fitness in female gymnasts: the gymnastics functional measurement tool. Int J Sports Phys Ther. 2012 Apr;7(2):124-38.</citation>
    <PMID>22530187</PMID>
  </reference>
  <reference>
    <citation>Widler KS, Glatthorn JF, Bizzini M, Impellizzeri FM, Munzinger U, Leunig M, Maffiuletti NA. Assessment of hip abductor muscle strength. A validity and reliability study. J Bone Joint Surg Am. 2009 Nov;91(11):2666-72. doi: 10.2106/JBJS.H.01119.</citation>
    <PMID>19884441</PMID>
  </reference>
  <verification_date>July 2015</verification_date>
  <study_first_submitted>July 23, 2014</study_first_submitted>
  <study_first_submitted_qc>July 24, 2014</study_first_submitted_qc>
  <study_first_posted type="Estimate">July 28, 2014</study_first_posted>
  <last_update_submitted>July 2, 2015</last_update_submitted>
  <last_update_submitted_qc>July 2, 2015</last_update_submitted_qc>
  <last_update_posted type="Estimate">July 7, 2015</last_update_posted>
  <responsible_party>
    <responsible_party_type>Principal Investigator</responsible_party_type>
    <investigator_affiliation>Nationwide Children's Hospital</investigator_affiliation>
    <investigator_full_name>Mitchell Selhorst</investigator_full_name>
    <investigator_title>Principle Investigator</investigator_title>
  </responsible_party>
  <keyword>low back pain</keyword>
  <keyword>pediatric</keyword>
  <keyword>gymnasts</keyword>
  <condition_browse>
    <!-- CAUTION:  The following MeSH terms are assigned with an imperfect algorithm            -->
    <mesh_term>Back Pain</mesh_term>
    <mesh_term>Low Back Pain</mesh_term>
  </condition_browse>
  <!-- Results have not yet been posted for this study                                          -->
</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/NCT02201966
org study id: IRB14-00229
nct id: NCT02201966
lead sponsor: 
has dmc: No
Low back pain is a common condition in children who perform gymnastics. Commonly, the injury
      is not the result of a specific injury, but is a stress injury to the lumbar spine. Regional
      interdependence is a theory that suggests when adjacent joints and muscles are not working
      properly increased stress is placed on a particular joint. This theory would suggest that if
      a patient did not have enough hip extension to perform a back bend increased motion would
      occur in the lumbar spine allowing the gymnast to complete the technique. Currently, no
      research links impairments in other joints to low back pain in gymnasts.

      This is a cross sectional study assessing the relationship between gymnast with back pain and
      flexibility and strength of the shoulder and hip joints. Investigators will travel to a local
      gymnastics training centers and assess the gymnasts' strength and flexibility of the the hips
      and shoulders. The gymnast will also fill our a questionnaire assessing if they have had back
      pain in the past month and how much has it limited their ability to participate in
      gymnastics. Investigators will be blinded to the results of this survey.

      The goal of this research study is to see if there are any link between strength and
      flexibility of the hips, and shoulders and gymnasts with low back pain. The investigators
      hypothesize that gymnasts who demonstrates impairments in strength and flexibility of the
      hips, or shoulders will be more likely to have complaints of low back pain.
Female gymnasts will fill out a survey prior having their strength and flexibility tested.
      The investigators will be blinded to the results of the survey.

      The questionaire asked the gymnasts several questions:

        1. Age

        2. Years in Gymnastics

        3. At what level did you last compete?

        4. On average how many hours per week do you participate in gymnastics?

        5. Have you had any back pain in the past month that has affected your ability to
           participate in gymnastics?

        6. If you answered yes to the last question: please rate your ability to participate in
           gymnastics with back pain?(0 represents unable to perform gymnastics and 100 represents
           no difficulty participating in gymnastics

      After the gymnast complete the survey the investigators will assess the flexibility and
      strength of their shoulder and hip muscles. Investigators will be blinded to survey results.
      Evaluation measures will be performed in a randomized manner. Subjects will randomly perform
      shoulder or hip testing first (determined by flip of coin). Flexibility and strength testing
      will also be determined randomly (determined by flip of coin).

      Evaluation measures

      Shoulder Flexibility Passive Motion test:

        -  Prior to shoulder flexibility testing, the gymnast's arm length is measured from the tip
           of the acromion process to a ½ inch wooden dowel grasped by both hands while holding
           their shoulders flexed to 90 degrees.

        -  For testing, the gymnast lies prone on a firm floor with their chin and nose touching
           the floor.

        -  Both arms are held parallel to the body with the shoulders flexed to 180 degrees.

        -  The gymnast grasps the ½ inch dowel with and overhand grip and the tips of her thumbs
           are touching.

        -  The evaluator maximally flexes the gymnasts shoulders while maintaining wrist in neutral
           position, elbows extended and their nose and chin in contact with the floor.

        -  Once the gymnast's arms are raised to maximum height, the distance from the dowel, where
           the thumbs are touching, to the floor is measured and recorded to the nearest ½
           centimeter using a rigid measuring stick.

        -  The Shoulder flexibility Passive Motion test raw score is calculated my dividing the
           dowel height attained by the length of the gymnast's arm.

      Shoulder Flexibility Active Motion test:

        -  Prior to shoulder flexibility testing, the gymnast's arm length is measured from the tip
           of the acromion process to a ½ inch wooden dowel grasped by both hands while holding
           their shoulders flexed to 90 degrees.

        -  For testing, the gymnast lies prone on a firm floor with their chin and nose touching
           the floor.

        -  Both arms are held parallel to the body with the shoulders flexed to 180 degrees.

        -  The gymnast grasps the ½ inch dowel with and overhand grip and the tips of her thumbs
           are touching.

        -  The gymnast is asked to maximally flex their shoulders while maintaining wrist in
           neutral position, elbows extended and their nose and chin in contact with the floor.

        -  Once the gymnast has raised their arms to the maximum height, the distance from the
           dowel, where the thumbs are touching, to the floor is measured and recorded to the
           nearest ½ centimeter using a rigid measuring stick.

        -  The Shoulder flexibility test raw score is calculated my dividing the dowel height
           attained by the length of the gymnast's arm.

      Hip Extension Flexibility test (Thomas test):

        -  Prior to hip extension flexibility testing, the gymnast lays flat on the examination
           table with legs extended. The examiner places the digital inclinometer on the anterior
           portion of the mid-thigh and zeros the inclinometer. The examiner marks the gymnast's
           skin at the distal most portion of the inclinometer in contact with the gymnast.

        -  Hip extension flexibility will be measured by using the modified Thomas test.

        -  The gymnast is instructed to sit as close to the edge of the examination table as
           possible.

        -  The gymnast supports their contralateral thigh with their arms and, with the assistance
           of the examiner, slowly rolls backward onto the table.

        -  The contralateral hip is flexed to the point that the gymnast's lumbar lordosis is
           flattened, and the right limb is allowed to hang unsupported off the table.

        -  The examiner palpates the lumbar spine to confirm that it remains in contact with the
           table.

        -  Thigh position is also monitored to prevent abduction of the thigh.

        -  When the final test position is achieved the examiner places the inclinometer on the
           gymnast's anterior thigh in line made prior to testing.

        -  0 degrees indicates the gymnast's thigh is parallel to the horizon. If the thigh was
           above horizontal the number from the digital inclinometer will be read as negative. If
           the thigh is below horizontal the number will be positive.

      Dynamometer Testing:

      After having received standardized instructions, subjects will perform a series of
      familiarization trials consisting of three submaximal contractions per side. Then maximal
      voluntary contraction strength will be measured. The side tested first will be randomized
      within each test session. All maximal voluntary contraction strength data provided by the
      dynamometer (in kilograms) will be normalized to body weight.

      Shoulder Flexion Strength test:

        -  Strength testing will be performed with hand held dynamometer stabilized by the
           examiner.

        -  For testing, the gymnast lies prone on a firm floor with their chin and nose touching
           the floor.

        -  Both arms are held parallel to the body with the shoulders flexed to 180 degrees.

        -  The gymnast grasps the ½ inch dowel with and overhand grip and the tips of her thumbs
           are touching.

        -  The dynamometer pad will be will located on the ½ inch dowel where the gymnasts thumbs
           meet.

        -  The gymnast is asked to maximally flex their shoulders pressing the dowel into the
           dynamometer pad as hard as they can while maintaining wrist in neutral position, elbows
           extended and their nose and chin in contact with the floor.

        -  Two to three maximal voluntary contraction trials will be permitted. A third trial is
           completed only if the difference between the first two maximal voluntary contractions is
           >10%.

        -  The duration of these contractions will be 5 seconds, and thirty seconds of rest will be
           given between trials.

        -  If gymnast is unable to actively flex shoulders to 180 degrees the strength test will be
           scored as 0.

      Isometric maximal voluntary contraction strength of the hip muscles will be measured with a
      portable dynamometer fixed to a custom made frame. The custom-made frame is firmly fixed to a
      physical therapy treatment table with use of screw clamps. The frame consisted of two
      vertical bars and 1 horizontal bar attached to the vertical bars so as to be perpendicular to
      the extremities. The dynamometer is fixed to the horizontal bar so as the testing pad can be
      positioned properly for testing.

      .

      Hip Extension Strength Dynamometer Test:

        -  Gymnast is in prone position on examination table with tested leg knee fully extended.
           Tested hip is in 5 degrees of extension with the knee in full extension.

        -  The dynamometer is fixed using the custom made frame

        -  The center of the dynamometer pad will be on the posterior aspect of the calcaneus

        -  Gymnast is told to stabilize themselves by holding onto the examination table

        -  Gymnasts is instructed to push as hard as they can against the dynamometer testing pad.

        -  Two to three maximal voluntary contraction trials will be permitted. A third trial is
           completed only if the difference between the first two maximal voluntary contractions is
           >10%.

        -  The duration of these contractions will be 5 seconds, and thirty seconds of rest will be
           given between trials.

      Hip Abduction Strength Dynamometer test:

        -  Gymnast is in sidelying position on examination table with tested leg knee fully
           extended.

        -  The contralateral hip and knee joints will be positioned at approximately 30 degrees of
           flexion for stability and comfort.

        -  Tested hip is in 10 degrees of abduction with the knee in full extension.

           •. The center of the dynamometer pad will be located 5 cm proximal to the lateral
           femoral condyle.

        -  Gymnast is told to stabilize themselves by holding onto the examination table.

        -  Gymnast is instructed to push as hard as they can against the dynamometer testing pad.

        -  The examiner will inspect the whole body position during the maximal voluntary
           contraction trials to ensure minimal compensation from pelvic rotation and flexion and
           rotation about the hip. If the examiner judges too much compensation, that test will not
           be recorded and the subject will be reinstructed in proper testing form.

        -  Two to three maximal voluntary contraction trials will be permitted. A third trial is
           completed only if the difference between the first two maximal voluntary contractions is
           >10%.

        -  The duration of these contractions will be 5 seconds, and thirty seconds of rest will be
           given between trials.
observational model: Cohort
time perspective: Cross-Sectional
measure: Presence of low back pain in past month
time frame: Baseline
description: Presence of significant low back pain that has affected gymnastics ability at time of evaluation
arm group label: Female gymnasts with low back pain
description: Subset of competitive female gymnasts who report significant low back pain that affects their ability to perform gymnastics.
arm group label: Female gymnasts without low back pain
description: Subset of competitive female gymnasts who deny significant low back pain that affects their ability to perform gymnastics.
study pop: 
sampling method: Non-Probability Sample
criteria: 
gender: Female
minimum age: 7 Years
maximum age: N/A
healthy volunteers: Accepts Healthy Volunteers
last name: Mitchell C Selhorst, DPT
role: Principal Investigator
affiliation: Nationwide Childrens Hospital
facility: 
country: United States
citation: Thorborg K, Petersen J, Magnusson SP, Holmich P. Clinical assessment of hip strength using a hand-held dynamometer is reliable. Scand J Med Sci Sports. 2010 Jun;20(3):493-501. doi: 10.1111/j.1600-0838.2009.00958.x. Epub 2009 Jun 23.
PMID: 19558384
citation: Sleeper MD, Kenyon LK, Casey E. Measuring fitness in female gymnasts: the gymnastics functional measurement tool. Int J Sports Phys Ther. 2012 Apr;7(2):124-38.
PMID: 22530187
citation: Widler KS, Glatthorn JF, Bizzini M, Impellizzeri FM, Munzinger U, Leunig M, Maffiuletti NA. Assessment of hip abductor muscle strength. A validity and reliability study. J Bone Joint Surg Am. 2009 Nov;91(11):2666-72. doi: 10.2106/JBJS.H.01119.
PMID: 19884441
responsible party type: Principal Investigator
investigator affiliation: Nationwide Children's Hospital
investigator full name: Mitchell Selhorst
investigator title: Principle Investigator
mesh term: Back Pain
mesh term: Low Back Pain