<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/NCT03044106</url>
  </required_header>
  <id_info>
    <org_study_id>16-0898</org_study_id>
    <nct_id>NCT03044106</nct_id>
  </id_info>
  <brief_title>Cranial Laser Reflex Technique for Hamstring Function</brief_title>
  <acronym>CLRTHam</acronym>
  <official_title>The Effects of Cranial Laser Reflex Technique on Hamstring Flexibility, Strength, and Pain Pressure Threshold: a Pilot Study</official_title>
  <sponsors>
    <lead_sponsor>
      <agency>University of North Carolina, Chapel Hill</agency>
      <agency_class>Other</agency_class>
    </lead_sponsor>
    <collaborator>
      <agency>North Carolina Translational and Clinical Sciences Institute</agency>
      <agency_class>Other</agency_class>
    </collaborator>
    <collaborator>
      <agency>National Institutes of Health (NIH)</agency>
      <agency_class>NIH</agency_class>
    </collaborator>
  </sponsors>
  <source>University of North Carolina, Chapel Hill</source>
  <oversight_info>
    <has_dmc>No</has_dmc>
    <is_fda_regulated_drug>No</is_fda_regulated_drug>
    <is_fda_regulated_device>Yes</is_fda_regulated_device>
    <is_us_export>No</is_us_export>
  </oversight_info>
  <brief_summary>
    <textblock>
      Purpose: To conduct a pilot study of the effect of Cranial Laser Reflex Technique (CLRT)&#xD;
      compared with sham laser on hamstring muscle flexibility, strength, and pain pressure&#xD;
      threshold.&#xD;
&#xD;
      Participants: Active, young adults ages 18 to 35.&#xD;
&#xD;
      Procedures: A two-visit, assessor and participant-blinded crossover study with 1-week&#xD;
      washout. Subjects will complete three functional hamstring tests before and after CLRT and&#xD;
      sham laser treatment. Subjects will also complete questionnaires to assess their expectations&#xD;
      and perceptions of the interventions.&#xD;
    </textblock>
  </brief_summary>
  <detailed_description>
    <textblock>
      First Visit: Subjects who met the inclusion criteria and gave consent completed a brief&#xD;
      questionnaire on their activity level, history of hamstring injuries, and perceived hamstring&#xD;
      tightness and were randomized to one of the following for the first treatment period: 1)&#xD;
      active CLRT; or 2) sham laser.&#xD;
&#xD;
      After randomization, subjects were asked to complete the three functional hamstring tests:&#xD;
      90-90 Knee Extension Angle (KEA) to assess flexibility, handheld dynamometry (HHD) for&#xD;
      strength, and pain pressure threshold (PPT).&#xD;
&#xD;
      Assessments. KEA: The 90-90 Knee Extension Angle test is a functional assessment designed to&#xD;
      assess lower extremity flexibility and is considered the gold standard for hamstring length.&#xD;
      The participant began in the supine position on a treatment table. The tested extremity (the&#xD;
      right leg in each subject) was placed in a 90° hip and 90° knee position with the&#xD;
      contralateral lower extremity placed flat on the table. A digital inclinometer was&#xD;
      consistently placed at the level of the medial malleoli and the superior pole of the patella.&#xD;
      The examiner maintained 90° of hip flexion. Pelvic position was monitored by palpation of the&#xD;
      anterior superior iliac spine and lumbar spinous processes to maintain a neutral pelvic&#xD;
      position. The examiner passively extended the knee to the point of a ''strong, but tolerable&#xD;
      stretch,&quot; as reported by the subject. The examiner read the angle of the inclinometer and&#xD;
      recorded the mean value of three attempts. A greater angle indicates greater degree of&#xD;
      flexibility.&#xD;
&#xD;
      Hand held Dynamometry (HHD) is currently considered a reliable and valid measurement of peak&#xD;
      muscle contraction. The subject began prone on the table with right leg bent to 90°. The&#xD;
      tester placed the dynamometer (microFET2; Hoggan Health Industries, Salt Lake City, UT) at&#xD;
      the heel of the participant and applied force to the heel, gradually increasing in 3 to 5&#xD;
      seconds. Participants was instructed to resist the applied force and maximally contract the&#xD;
      hamstring muscle against the HHD device. The test ended once they are no longer able to&#xD;
      resist the force and the leg begins to move (break point). The investigator recorded the mean&#xD;
      value of three attempts.&#xD;
&#xD;
      Pain Pressure Threshold (PPT) is a reliable, accurate and valid method for measuring muscle&#xD;
      pain sensitivity and response to treatment. The digital algometer (FDX, Wagner Instruments,&#xD;
      Greenwich, CT) is a hand-held muscle tester with a range of 0-100 lbf that consists of a&#xD;
      padded disc with a diameter of 0.5&quot; attached to a microprocessor-control unit that measures&#xD;
      peak force (pounds or kilograms). The unit has a digital readout for peak-applied pressure&#xD;
      and provides a built-in calibration routine that verifies a valid calibration. In order to&#xD;
      determine PPT, the researcher applied the tip of the algometer to a tender spot in the&#xD;
      participant's hamstrings and increased the amount of pressure until the participant verbally&#xD;
      informed the researcher when the sensation of pressure became pain. At this point the&#xD;
      algometer was removed and the peak force recorded. The mean of three repeated measures was&#xD;
      reported.&#xD;
&#xD;
      Intervention: Cranial Laser Reflex Technique (CLRT) is a novel complementary and alternative&#xD;
      (CAM) medicine intervention for musculoskeletal conditions that incorporates principles of&#xD;
      laser acupuncture with chiropractic cranial reflexology. Subjects wore protective eyewear.&#xD;
      The hamstring reflexes are two lines on the posterior portion of the top of the head,&#xD;
      approximately 2 cm long and 2 cm apart, running parallel to the sagittal suture. The&#xD;
      posterior end of the reflexes can be located by finding the vertex, or CZ point in the&#xD;
      standardized 10-20 EEG system, and moving laterally approximately 1 cm.&#xD;
&#xD;
      The aperture of the laser probe was placed at the posterior end of the reflex (b), turned on&#xD;
      and moved anteriorly to point (a) at a speed of approximately 2 cm/s. The laser was turned&#xD;
      off and quickly returned to the starting point, turned on and moved again. This was repeated&#xD;
      for a total of 30 times. The probe skimmed the surface of the scalp, moving aside as much&#xD;
      hair as possible.&#xD;
&#xD;
      Device: The treatment device used in this study is a Class IIIB 810nm 200 milliwatts (mW)&#xD;
      near-infrared diode laser (THOR Photomedicine Ltd, Great Britain) that is currently marketed&#xD;
      in the US. The laser probe is FDA-cleared and classified as a non-significant risk device.&#xD;
      The spot size is 0.0364 cm^2, and the treatment time is 30 seconds. Current best-practice&#xD;
      recommendations for laser acupuncture recommend a dosage between 1-4 J/cm^2 per point. Since&#xD;
      the CRP is a line of 2 cm, for the purposes of calculating dosage, it was treated as a series&#xD;
      of 10 connected points each with a diameter of 2mm. With the scanning rate of 2cm/s, each&#xD;
      &quot;point&quot; on the line received 1/10 of each pass, totaling 3s (out of 30s total) exposure time&#xD;
      per point. The dose per point for this intervention is calculated to be approximately 1.65&#xD;
      J/cm^2.&#xD;
&#xD;
      There was a one-week washout and the subject will return for the second treatment period.&#xD;
&#xD;
      Primary Outcome: Hamstring flexibility (90-90 Knee Extension Angle, KEA) A clinically&#xD;
      significant effect size is an increase of 5 degrees. The investigator recorded the mean value&#xD;
      of three attempts. Hypothesis: CLRT will increase hamstring flexibility.&#xD;
&#xD;
      Secondary Outcomes:&#xD;
&#xD;
        1. Hamstring Strength as assessed by Handheld Dynamometry. HHD . The investigator recorded&#xD;
           the mean value of three attempts. Hypothesis: CLRT will have a neutral to positive&#xD;
           effect on hamstring strength.&#xD;
&#xD;
        2. Pain Pressure Threshold. The mean of three repeated measures was reported. An increase&#xD;
           in PPT signifies an increase in pain tolerance. Hypothesis: CLRT will increase pain&#xD;
           tolerance.&#xD;
&#xD;
        3. Age, gender, activity level, perceived hamstring tightness, perceived hamstring&#xD;
           flexibility and perceived hamstring strength were assessed at baseline and subsequent&#xD;
           follow up visit. Results were stratified by these variables to assess interaction with&#xD;
           treatment.&#xD;
&#xD;
      Sample Size and Power: Based on previously published results, a mean increase of 5º on the&#xD;
      KEA (e.g., from 135º to 140º) is considered to be clinically meaningful, assuming a common&#xD;
      standard deviation of 15º. It is also assumed that correlation between repeated measurements&#xD;
      from the same individual will be at least 0.75 (likely a conservative assumption). Under&#xD;
      these assumptions, enrolling 38 participants would provide at least 80% power using a&#xD;
      two-sided test at the 0.05 level.&#xD;
    </textblock>
  </detailed_description>
  <overall_status>Completed</overall_status>
  <start_date type="Actual">March 4, 2017</start_date>
  <completion_date type="Actual">July 31, 2017</completion_date>
  <primary_completion_date type="Actual">July 31, 2017</primary_completion_date>
  <phase>N/A</phase>
  <study_type>Interventional</study_type>
  <has_expanded_access>No</has_expanded_access>
  <study_design_info>
    <allocation>Randomized</allocation>
    <intervention_model>Crossover Assignment</intervention_model>
    <intervention_model_description>Subjects who meet the inclusion criteria and give consent were randomized to one of the following for the first treatment period: 1) active CLRT; or 2) sham laser. At the first intervention visit, the research assistant entered the subject's assigned identification into an online computer program (selected by study biostatistician) to determine assignment to one of the two periods. The study biostatistician used computer-generated random numbers to generate the allocation sequence using random blocks of random sizes. A one-week washout period minimized carryover effects.</intervention_model_description>
    <primary_purpose>Treatment</primary_purpose>
    <masking>Double (Participant, Outcomes Assessor)</masking>
    <masking_description>Subjects and assessors were blinded to treatment allocation. The subject was face down, eyes closed, and wearing protective eyewear that blocks the specific wavelength of the laser light during the intervention.&#xD;
After each treatment session, the participants completed a de-blinding questionnaire administrated by the assessor providing a dichotomous 'yes' or 'no' answer as to whether active treatment was received. This response was followed by a second question regarding how certain they were that active treatment was received on a 0-10 numeric rating scale (NRS), where 0 represents absolutely uncertain and 10 represents absolutely certain.</masking_description>
  </study_design_info>
  <primary_outcome>
    <measure>90-90 Knee Extension Angle Test</measure>
    <time_frame>At baseline and immediately after intervention</time_frame>
    <description>Knee Extension Angle (KEA) test is a functional test designed to assess lower extremity flexibility and is considered the gold standard test for assessing hamstring length. Results will be recorded as degrees of knee flexion angle. A clinically significant effect size is an increase of 5 degrees.</description>
  </primary_outcome>
  <secondary_outcome>
    <measure>Handheld Dynamometry</measure>
    <time_frame>At baseline and immediately after intervention</time_frame>
    <description>Handheld Dynamometry (HHD) is measures peak muscle contraction. The measurements will be recorded as kilograms (kg) and higher scores indicate higher muscle strength. The subject will be prone on the table with right leg bent to 90° and will maximally contract the hamstring muscle for 4-5 seconds against the HHD device. The investigator will record the mean value of three attempts. Higher scores indicate greater strength.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Pain Pressure Threshold</measure>
    <time_frame>At baseline and immediately after intervention</time_frame>
    <description>PPT is a reliable, accurate and valid method for measuring muscle pain sensitivity and response to treatment. In order to determine PPT, the researcher will apply the tip of the algometer to a tender spot in the participant's hamstrings and increase the amount of pressure until the participant verbally informs the researcher when the sensation of pressure became pain. At this point the algometer is removed and the peak force recorded. The mean of three repeated measures will be reported. An increase in PPT signifies an increase in pain tolerance and a decrease in pain sensitivity.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Mean Difference Pre/Post KEA, Stratified by History of Prior Hamstring Strain</measure>
    <time_frame>At baseline and immediately after intervention</time_frame>
    <description>Mean difference between active CLRT and Sham in hamstring flexibility (KEA) stratified by a history of prior hamstring injury. 8 participants reported prior injuries, 36 reported having no prior hamstring strain.</description>
  </secondary_outcome>
  <number_of_arms>2</number_of_arms>
  <enrollment type="Actual">44</enrollment>
  <condition>Hamstring Injury</condition>
  <condition>Muscle Tone Increased</condition>
  <condition>Muscle Pain</condition>
  <condition>Muscle Weakness</condition>
  <arm_group>
    <arm_group_label>CLRT, Then Sham</arm_group_label>
    <arm_group_type>Active Comparator</arm_group_type>
    <description>Subjects performed the KEA, HHD, PPT functional tests on their right hamstring before and after the CLRT intervention.</description>
  </arm_group>
  <arm_group>
    <arm_group_label>Sham, Then CLRT</arm_group_label>
    <arm_group_type>Sham Comparator</arm_group_type>
    <description>The Sham procedure was identical to CLRT except the laser device was placed in placebo mode: all device indicator lights and sounds will be functional but no laser light will be emitted from probe aperture.</description>
  </arm_group>
  <intervention>
    <intervention_type>Device</intervention_type>
    <intervention_name>CLRT</intervention_name>
    <description>CLRT is a novel method of laser stimulation on specific cranial reflex points that modulate muscle tone.</description>
    <arm_group_label>CLRT, Then Sham</arm_group_label>
    <arm_group_label>Sham, Then CLRT</arm_group_label>
    <other_name>Cranial Laser Reflex Technique</other_name>
  </intervention>
  <eligibility>
    <criteria>
      <textblock>
        Inclusion Criteria:&#xD;
&#xD;
          1. Between 18-35 years of age&#xD;
&#xD;
          2. All genders&#xD;
&#xD;
          3. Willing to complete two study visits over 2-3 weeks&#xD;
&#xD;
          4. Able to read and communicate in English&#xD;
&#xD;
        Exclusion Criteria:&#xD;
&#xD;
          1. Current lower back condition with pain, numbness or tingling that radiates down the&#xD;
             legs&#xD;
&#xD;
          2. Active treatment for a major medical illness, such as heart disease, uncontrolled&#xD;
             diabetes or hypertension, malignancy, autoimmune, or immune deficiency disorder&#xD;
&#xD;
          3. History of vasculitis, intracranial mass, clotting disorder (including&#xD;
             medication-induced, e.g., warfarin)&#xD;
&#xD;
          4. Current skin malignancy on scalp&#xD;
&#xD;
          5. Cognitive dysfunction preventing informed consent&#xD;
&#xD;
          6. Pending or currently receiving benefits from personal injury litigation, including&#xD;
             worker's compensation&#xD;
&#xD;
          7. Chronic long-term disability related to lumbosacral injury/symptoms&#xD;
&#xD;
          8. Epilepsy&#xD;
      </textblock>
    </criteria>
    <gender>All</gender>
    <minimum_age>18 Years</minimum_age>
    <maximum_age>35 Years</maximum_age>
    <healthy_volunteers>Accepts Healthy Volunteers</healthy_volunteers>
  </eligibility>
  <overall_official>
    <last_name>Nicholas A Wise, D.C.</last_name>
    <role>Principal Investigator</role>
    <affiliation>University of North Carolina, Chapel Hill</affiliation>
  </overall_official>
  <location>
    <facility>
      <name>UNC- Chapel Hill</name>
      <address>
        <city>Chapel Hill</city>
        <state>North Carolina</state>
        <zip>27514</zip>
        <country>United States</country>
      </address>
    </facility>
  </location>
  <location_countries>
    <country>United States</country>
  </location_countries>
  <verification_date>October 2017</verification_date>
  <study_first_submitted>February 2, 2017</study_first_submitted>
  <study_first_submitted_qc>February 2, 2017</study_first_submitted_qc>
  <study_first_posted type="Estimate">February 6, 2017</study_first_posted>
  <results_first_submitted>October 3, 2018</results_first_submitted>
  <results_first_submitted_qc>January 7, 2019</results_first_submitted_qc>
  <results_first_posted type="Actual">January 29, 2019</results_first_posted>
  <last_update_submitted>January 28, 2019</last_update_submitted>
  <last_update_submitted_qc>January 28, 2019</last_update_submitted_qc>
  <last_update_posted type="Actual">February 12, 2019</last_update_posted>
  <responsible_party>
    <responsible_party_type>Sponsor</responsible_party_type>
  </responsible_party>
  <keyword>hamstrings</keyword>
  <keyword>flexibility</keyword>
  <keyword>strength</keyword>
  <keyword>pain pressure threshold</keyword>
  <keyword>lllt</keyword>
  <keyword>photobiomodulation</keyword>
  <keyword>cranial reflex</keyword>
  <keyword>cranial laser reflex technique</keyword>
  <keyword>CLRT</keyword>
  <condition_browse>
    <!-- CAUTION:  The following MeSH terms are assigned with an imperfect algorithm            -->
    <mesh_term>Muscle Weakness</mesh_term>
    <mesh_term>Myalgia</mesh_term>
    <mesh_term>Muscle Hypertonia</mesh_term>
  </condition_browse>
  <patient_data>
    <sharing_ipd>No</sharing_ipd>
  </patient_data>
  <provided_document_section>
    <provided_document>
      <document_type>Study Protocol and Statistical Analysis Plan</document_type>
      <document_has_protocol>Yes</document_has_protocol>
      <document_has_icf>No</document_has_icf>
      <document_has_sap>Yes</document_has_sap>
      <document_date>January 25, 2017</document_date>
      <document_url>https://ClinicalTrials.gov/ProvidedDocs/06/NCT03044106/Prot_SAP_000.pdf</document_url>
    </provided_document>
  </provided_document_section>

  <clinical_results>

    <participant_flow>
      <group_list>
        <group group_id="P1">
          <title>CLRT, Then SHAM</title>
          <description>Subject will perform KEA (knee extension angle), HHD (handheld dynamometry), PPT (pain pressure threshold) functional tests. Investigator will record the mean of 3 attempts for each test. Subject will don protective eyewear. CLRT (Cranial Laser Reflex Technique) will be performed: the aperture of the laser probe will be placed at one end of the reflex (a), turned on and moved to the end of the reflex (b) at a speed of approximately 2 cm/s. The laser will be turned off and quickly returned to point (a), turned on and moved to point (b) again. This will be repeated for a total of 30 times. After CLRT is completed, the KEA, PPT and HHD tests will be repeated and the mean of 3 attempts for each will be recorded.</description>
        </group>
        <group group_id="P2">
          <title>SHAM, Then CLRT</title>
          <description>The identical procedures will be followed as in the other arm. The only difference is the the laser device will be in sham mode: all lights and sounds are operational with no laser emission from the aperture.</description>
        </group>
      </group_list>
      <period_list>
        <period>
          <title>Visit 1</title>
          <milestone_list>
            <milestone>
              <title>STARTED</title>
              <participants_list>
                <participants group_id="P1" count="22"/>
                <participants group_id="P2" count="22"/>
              </participants_list>
            </milestone>
            <milestone>
              <title>COMPLETED</title>
              <participants_list>
                <participants group_id="P1" count="22"/>
                <participants group_id="P2" count="22"/>
              </participants_list>
            </milestone>
            <milestone>
              <title>NOT COMPLETED</title>
              <participants_list>
                <participants group_id="P1" count="0"/>
                <participants group_id="P2" count="0"/>
              </participants_list>
            </milestone>
          </milestone_list>
        </period>
        <period>
          <title>Washout (1 Week)</title>
          <milestone_list>
            <milestone>
              <title>STARTED</title>
              <participants_list>
                <participants group_id="P1" count="22"/>
                <participants group_id="P2" count="22"/>
              </participants_list>
            </milestone>
            <milestone>
              <title>COMPLETED</title>
              <participants_list>
                <participants group_id="P1" count="22"/>
                <participants group_id="P2" count="20"/>
              </participants_list>
            </milestone>
            <milestone>
              <title>NOT COMPLETED</title>
              <participants_list>
                <participants group_id="P1" count="0"/>
                <participants group_id="P2" count="2"/>
              </participants_list>
            </milestone>
          </milestone_list>
          <drop_withdraw_reason_list>
            <drop_withdraw_reason>
              <title>Withdrawal by Subject</title>
              <participants_list>
                <participants group_id="P1" count="0"/>
                <participants group_id="P2" count="2"/>
              </participants_list>
            </drop_withdraw_reason>
          </drop_withdraw_reason_list>
        </period>
        <period>
          <title>Visit 2</title>
          <milestone_list>
            <milestone>
              <title>STARTED</title>
              <participants_list>
                <participants group_id="P1" count="22"/>
                <participants group_id="P2" count="20"/>
              </participants_list>
            </milestone>
            <milestone>
              <title>COMPLETED</title>
              <participants_list>
                <participants group_id="P1" count="22"/>
                <participants group_id="P2" count="20"/>
              </participants_list>
            </milestone>
            <milestone>
              <title>NOT COMPLETED</title>
              <participants_list>
                <participants group_id="P1" count="0"/>
                <participants group_id="P2" count="0"/>
              </participants_list>
            </milestone>
          </milestone_list>
        </period>
      </period_list>
    </participant_flow>

    <baseline>
      <group_list>
        <group group_id="B1">
          <title>All Participants</title>
          <description>This is the total of all participants that began the trial and completed at least one visit.</description>
        </group>
      </group_list>
      <analyzed_list>
        <analyzed>
          <units>Participants</units>
          <scope>Overall</scope>
          <count_list>
            <count group_id="B1" value="44"/>
          </count_list>
        </analyzed>
      </analyzed_list>
      <measure_list>
        <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="24.02" spread="3.14"/>
                  </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="36"/>
                  </measurement_list>
                </category>
                <category>
                  <title>Male</title>
                  <measurement_list>
                    <measurement group_id="B1" value="8"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
        <measure>
          <title>Ethnicity (NIH/OMB)</title>
          <units>Participants</units>
          <param>Count of Participants</param>
          <class_list>
            <class>
              <category_list>
                <category>
                  <title>Hispanic or Latino</title>
                  <measurement_list>
                    <measurement group_id="B1" value="3"/>
                  </measurement_list>
                </category>
                <category>
                  <title>Not Hispanic or Latino</title>
                  <measurement_list>
                    <measurement group_id="B1" value="41"/>
                  </measurement_list>
                </category>
                <category>
                  <title>Unknown or Not Reported</title>
                  <measurement_list>
                    <measurement group_id="B1" value="0"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
        <measure>
          <title>Race (NIH/OMB)</title>
          <units>Participants</units>
          <param>Count of Participants</param>
          <class_list>
            <class>
              <category_list>
                <category>
                  <title>American Indian or Alaska Native</title>
                  <measurement_list>
                    <measurement group_id="B1" value="0"/>
                  </measurement_list>
                </category>
                <category>
                  <title>Asian</title>
                  <measurement_list>
                    <measurement group_id="B1" value="1"/>
                  </measurement_list>
                </category>
                <category>
                  <title>Native Hawaiian or Other Pacific Islander</title>
                  <measurement_list>
                    <measurement group_id="B1" value="0"/>
                  </measurement_list>
                </category>
                <category>
                  <title>Black or African American</title>
                  <measurement_list>
                    <measurement group_id="B1" value="3"/>
                  </measurement_list>
                </category>
                <category>
                  <title>White</title>
                  <measurement_list>
                    <measurement group_id="B1" value="38"/>
                  </measurement_list>
                </category>
                <category>
                  <title>More than one race</title>
                  <measurement_list>
                    <measurement group_id="B1" value="2"/>
                  </measurement_list>
                </category>
                <category>
                  <title>Unknown or Not Reported</title>
                  <measurement_list>
                    <measurement group_id="B1" value="0"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
        <measure>
          <title>Injury, either leg, last 6 months</title>
          <units>Participants</units>
          <param>Count of Participants</param>
          <class_list>
            <class>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="B1" value="4"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
        <measure>
          <title>surgery to either leg, ever</title>
          <units>participants</units>
          <param>Number</param>
          <class_list>
            <class>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="B1" value="5"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
        <measure>
          <title>Prior hamstring strain history</title>
          <units>Participants</units>
          <param>Count of Participants</param>
          <class_list>
            <class>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="B1" value="8"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
        <measure>
          <title>Subjective hamstring tightness</title>
          <units>Participants</units>
          <param>Count of Participants</param>
          <class_list>
            <class>
              <category_list>
                <category>
                  <title>Very tight</title>
                  <measurement_list>
                    <measurement group_id="B1" value="5"/>
                  </measurement_list>
                </category>
                <category>
                  <title>Somewhat tight</title>
                  <measurement_list>
                    <measurement group_id="B1" value="20"/>
                  </measurement_list>
                </category>
                <category>
                  <title>A little tight</title>
                  <measurement_list>
                    <measurement group_id="B1" value="11"/>
                  </measurement_list>
                </category>
                <category>
                  <title>Not at all tight</title>
                  <measurement_list>
                    <measurement group_id="B1" value="4"/>
                  </measurement_list>
                </category>
                <category>
                  <title>Unknown</title>
                  <measurement_list>
                    <measurement group_id="B1" value="4"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </measure_list>
    </baseline>

    <outcome_list>
      <outcome>
        <type>Primary</type>
        <title>90-90 Knee Extension Angle Test</title>
        <description>Knee Extension Angle (KEA) test is a functional test designed to assess lower extremity flexibility and is considered the gold standard test for assessing hamstring length. Results will be recorded as degrees of knee flexion angle. A clinically significant effect size is an increase of 5 degrees.</description>
        <time_frame>At baseline and immediately after intervention</time_frame>
        <population>Analysis was conducted on intention to treat.</population>
        <group_list>
          <group group_id="O1">
            <title>CLRT</title>
            <description>Subject will don protective eyewear. The hamstring reflexes are two lines on the posterior portion of the top of the head. The treatment device to be used in this study is a Class 3B, 810 nanometer (nm), 200 milliwatt (mW) near-infrared diode laser (THOR Photomedicine Ltd, Great Britain) that is currently marketed in the US.The aperture of the laser probe will be placed at the posterior end of the reflex, turned on and moved to the anterior end of the reflex at a speed of approximately 2 cm/s. The laser will be turned off and quickly returned to point (a), turned on and moved to point (b) again. This will be repeated for a total of 30 times.</description>
          </group>
          <group group_id="O2">
            <title>SHAM</title>
            <description>The Sham procedure will be identical to CLRT except the laser device will be in placebo mode: all device indicator lights and sounds will be functional but no laser light will be emitted from probe aperture.</description>
          </group>
        </group_list>
        <measure>
          <title>90-90 Knee Extension Angle Test</title>
          <description>Knee Extension Angle (KEA) test is a functional test designed to assess lower extremity flexibility and is considered the gold standard test for assessing hamstring length. Results will be recorded as degrees of knee flexion angle. A clinically significant effect size is an increase of 5 degrees.</description>
          <population>Analysis was conducted on intention to treat.</population>
          <units>degrees</units>
          <param>Mean</param>
          <dispersion>Standard Deviation</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="42"/>
                <count group_id="O2" value="44"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>KEA at baseline/pre-intervention</title>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="167.3" spread="8.4"/>
                    <measurement group_id="O2" value="166.4" spread="8.8"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>KEA immediately post-intervention</title>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="168.5" spread="9.3"/>
                    <measurement group_id="O2" value="168.8" spread="7.5"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Secondary</type>
        <title>Handheld Dynamometry</title>
        <description>Handheld Dynamometry (HHD) is measures peak muscle contraction. The measurements will be recorded as kilograms (kg) and higher scores indicate higher muscle strength. The subject will be prone on the table with right leg bent to 90° and will maximally contract the hamstring muscle for 4-5 seconds against the HHD device. The investigator will record the mean value of three attempts. Higher scores indicate greater strength.</description>
        <time_frame>At baseline and immediately after intervention</time_frame>
        <population>Intention to treat.</population>
        <group_list>
          <group group_id="O1">
            <title>CLRT</title>
            <description>Subject will don protective eyewear. The hamstring reflexes are two lines on the posterior portion of the top of the head. The aperture of the laser probe will be placed at the posterior end of the reflex (a), turned on and moved to the anterior end of the reflex (b) at a speed of approximately 2 cm/s. The laser will be turned off and quickly returned to point (a), turned on and moved to point (b) again. This will be repeated for a total of 30 times.&#xD;
The spot size is 0.0364 cm², and the treatment time is 30 seconds. Since the CRP is a line of 2 cm, for the purposes of calculating dosage, we will treat it as a series of 10 connected points each with a diameter of 2mm. With the scanning rate of 2 cm/s, each &quot;point&quot; on the line will receive 1/10 of each pass, totaling 3s (out of 30s total) exposure time per point. The dose per &quot;point&quot; for this intervention is calculated to be approximately 1.65 J/cm².</description>
          </group>
          <group group_id="O2">
            <title>Sham</title>
            <description>The Sham procedure will be identical to CLRT except the laser device will be in placebo mode: all device indicator lights and sounds will be functional but no laser light will be emitted from probe aperture.</description>
          </group>
        </group_list>
        <measure>
          <title>Handheld Dynamometry</title>
          <description>Handheld Dynamometry (HHD) is measures peak muscle contraction. The measurements will be recorded as kilograms (kg) and higher scores indicate higher muscle strength. The subject will be prone on the table with right leg bent to 90° and will maximally contract the hamstring muscle for 4-5 seconds against the HHD device. The investigator will record the mean value of three attempts. Higher scores indicate greater strength.</description>
          <population>Intention to treat.</population>
          <units>Kilograms</units>
          <param>Mean</param>
          <dispersion>Standard Deviation</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="42"/>
                <count group_id="O2" value="44"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>HHD at baseline/pre-intervention</title>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="17.2" spread="4.7"/>
                    <measurement group_id="O2" value="17.4" spread="4.6"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>HHD immediately post-intervention</title>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="16.9" spread="4.5"/>
                    <measurement group_id="O2" value="17.0" spread="4.7"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Secondary</type>
        <title>Pain Pressure Threshold</title>
        <description>PPT is a reliable, accurate and valid method for measuring muscle pain sensitivity and response to treatment. In order to determine PPT, the researcher will apply the tip of the algometer to a tender spot in the participant's hamstrings and increase the amount of pressure until the participant verbally informs the researcher when the sensation of pressure became pain. At this point the algometer is removed and the peak force recorded. The mean of three repeated measures will be reported. An increase in PPT signifies an increase in pain tolerance and a decrease in pain sensitivity.</description>
        <time_frame>At baseline and immediately after intervention</time_frame>
        <population>Intention to treat.</population>
        <group_list>
          <group group_id="O1">
            <title>CLRT</title>
            <description>Subject will don protective eyewear. The hamstring reflexes are two lines on the posterior portion of the top of the head. The aperture of the laser probe will be placed at the posterior end of the reflex (a), turned on and moved to the anterior end of the reflex (b) at a speed of approximately 2 cm/s. The laser will be turned off and quickly returned to point (a), turned on and moved to point (b) again. This will be repeated for a total of 30 times.&#xD;
The spot size is 0.0364 cm², and the treatment time is 30 seconds. Since the CRP is a line of 2 cm, for the purposes of calculating dosage, we will treat it as a series of 10 connected points each with a diameter of 2mm. With the scanning rate of 2cm/s, each &quot;point&quot; on the line will receive 1/10 of each pass, totaling 3s (out of 30 s total) exposure time per point. The dose per &quot;point&quot; for this intervention is calculated to be approximately 1.65 J/cm².</description>
          </group>
          <group group_id="O2">
            <title>Sham</title>
            <description>The Sham procedure will be identical to CLRT except the laser device will be in placebo mode: all device indicator lights and sounds will be functional but no laser light will be emitted from probe aperture.</description>
          </group>
        </group_list>
        <measure>
          <title>Pain Pressure Threshold</title>
          <description>PPT is a reliable, accurate and valid method for measuring muscle pain sensitivity and response to treatment. In order to determine PPT, the researcher will apply the tip of the algometer to a tender spot in the participant's hamstrings and increase the amount of pressure until the participant verbally informs the researcher when the sensation of pressure became pain. At this point the algometer is removed and the peak force recorded. The mean of three repeated measures will be reported. An increase in PPT signifies an increase in pain tolerance and a decrease in pain sensitivity.</description>
          <population>Intention to treat.</population>
          <units>kgf</units>
          <param>Mean</param>
          <dispersion>Standard Deviation</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="42"/>
                <count group_id="O2" value="44"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>PPT at baseline/pre-intervention</title>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="10.6" spread="3.6"/>
                    <measurement group_id="O2" value="11.0" spread="3.9"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>PPT immediately post-intervention</title>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="11.3" spread="4.6"/>
                    <measurement group_id="O2" value="11.5" spread="4.5"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Secondary</type>
        <title>Mean Difference Pre/Post KEA, Stratified by History of Prior Hamstring Strain</title>
        <description>Mean difference between active CLRT and Sham in hamstring flexibility (KEA) stratified by a history of prior hamstring injury. 8 participants reported prior injuries, 36 reported having no prior hamstring strain.</description>
        <time_frame>At baseline and immediately after intervention</time_frame>
        <population>Mean difference in pre/post KEA after receiving active CLRT and Sham in hamstring flexibility (KEA), stratified by a history of prior hamstring injury.</population>
        <group_list>
          <group group_id="O1">
            <title>Active CLRT, History of Hamstring Strain</title>
            <description>Participants receiving active treatment who reported a prior history of hamstring strain (n=8). This group approximates a clinical population.</description>
          </group>
          <group group_id="O2">
            <title>Sham CLRT With History of Hamstring Strain</title>
            <description>Participants receiving sham treatment who reported a prior history of hamstring strain (n=8)</description>
          </group>
          <group group_id="O3">
            <title>Active CLRT With no Prior Hamstring Strain</title>
            <description>Participants receiving active treatment who reported no prior history of hamstring strain (n=36)</description>
          </group>
          <group group_id="O4">
            <title>Sham CLRT With no History of Hamstring Strain</title>
            <description>Participants receiving sham CLRT with no history of hamstring strain</description>
          </group>
        </group_list>
        <measure>
          <title>Mean Difference Pre/Post KEA, Stratified by History of Prior Hamstring Strain</title>
          <description>Mean difference between active CLRT and Sham in hamstring flexibility (KEA) stratified by a history of prior hamstring injury. 8 participants reported prior injuries, 36 reported having no prior hamstring strain.</description>
          <population>Mean difference in pre/post KEA after receiving active CLRT and Sham in hamstring flexibility (KEA), stratified by a history of prior hamstring injury.</population>
          <units>degrees</units>
          <param>Mean</param>
          <dispersion>Standard Deviation</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="8"/>
                <count group_id="O2" value="8"/>
                <count group_id="O3" value="36"/>
                <count group_id="O4" value="36"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>PRE KEA</title>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="167.825" spread="7.925141"/>
                    <measurement group_id="O2" value="168.4875" spread="8.898384"/>
                    <measurement group_id="O3" value="167.1778" spread="8.58657"/>
                    <measurement group_id="O4" value="165.9235" spread="8.778143"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>POST KEA</title>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="171.65" spread="6.762501"/>
                    <measurement group_id="O2" value="169.4875" spread="8.092225"/>
                    <measurement group_id="O3" value="167.8417" spread="9.658316"/>
                    <measurement group_id="O4" value="168.6118" spread="7.420887"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
        <analysis_list>
          <analysis>
            <group_id_list>
              <group_id>O1</group_id>
            </group_id_list>
            <groups_desc>This is the difference between pre and post KEA in those receiving the active treatment with a history of hamstring strain.</groups_desc>
            <non_inferiority_type>Superiority</non_inferiority_type>
            <p_value>0.0068</p_value>
            <method>t-test, 2 sided</method>
            <param_type>Mean Difference (Final Values)</param_type>
            <param_value>3.825</param_value>
            <dispersion_type>Standard Deviation</dispersion_type>
            <dispersion_value>3.308759</dispersion_value>
            <ci_percent>95</ci_percent>
            <ci_n_sides>2-Sided</ci_n_sides>
            <ci_lower_limit>1.058809</ci_lower_limit>
            <ci_upper_limit>6.591192</ci_upper_limit>
          </analysis>
          <analysis>
            <group_id_list>
              <group_id>O2</group_id>
            </group_id_list>
            <groups_desc>This is the difference in pre /post KEA means after receiving the sham treatment in those with a history of hamstring strains.</groups_desc>
            <non_inferiority_type>Superiority</non_inferiority_type>
            <p_value>0.2185</p_value>
            <method>t-test, 2 sided</method>
            <param_type>Median Difference (Final Values)</param_type>
            <param_value>1.0</param_value>
            <dispersion_type>Standard Deviation</dispersion_type>
            <dispersion_value>3.431784</dispersion_value>
            <ci_percent>95</ci_percent>
            <ci_n_sides>2-Sided</ci_n_sides>
            <ci_lower_limit>-1.869044</ci_lower_limit>
            <ci_upper_limit>3.869044</ci_upper_limit>
          </analysis>
          <analysis>
            <group_id_list>
              <group_id>O3</group_id>
            </group_id_list>
            <groups_desc>This is the difference in pre/post KEA means in those receiving the active treatment with no history of hamstring strain.</groups_desc>
            <non_inferiority_type>Superiority</non_inferiority_type>
            <p_value>0.1281</p_value>
            <method>t-test, 2 sided</method>
            <param_type>Mean Difference (Final Values)</param_type>
            <param_value>.6638904</param_value>
            <dispersion_type>Standard Deviation</dispersion_type>
            <dispersion_value>3.450892</dispersion_value>
            <ci_percent>95</ci_percent>
            <ci_n_sides>2-Sided</ci_n_sides>
            <ci_lower_limit>-.5037233</ci_lower_limit>
            <ci_upper_limit>1.831504</ci_upper_limit>
          </analysis>
          <analysis>
            <group_id_list>
              <group_id>O4</group_id>
            </group_id_list>
            <groups_desc>This is the difference in pre/post KEA means in those receiving the sham treatment who have no history of hamstring strain.</groups_desc>
            <non_inferiority_type>Superiority</non_inferiority_type>
            <p_value>0.00</p_value>
            <method>t-test, 2 sided</method>
            <param_type>Mean Difference (Final Values)</param_type>
            <param_value>2.688237</param_value>
            <dispersion_type>Standard Deviation</dispersion_type>
            <dispersion_value>3.241751</dispersion_value>
            <ci_percent>95</ci_percent>
            <ci_n_sides>2-Sided</ci_n_sides>
            <ci_lower_limit>1.557137</ci_lower_limit>
            <ci_upper_limit>3.819337</ci_upper_limit>
          </analysis>
          <analysis>
            <group_id_list>
              <group_id>O1</group_id>
              <group_id>O2</group_id>
            </group_id_list>
            <groups_desc>This is the mean difference in effect between active and sham in those with a history of hamstring strain</groups_desc>
            <non_inferiority_type>Superiority</non_inferiority_type>
            <p_value>0.090</p_value>
            <method>Mixed Models Analysis</method>
            <param_type>Mean Difference (Final Values)</param_type>
            <param_value>2.825</param_value>
            <ci_percent>95</ci_percent>
            <ci_n_sides>2-Sided</ci_n_sides>
            <ci_lower_limit>-0.4543</ci_lower_limit>
            <ci_upper_limit>6.0581</ci_upper_limit>
          </analysis>
          <analysis>
            <group_id_list>
              <group_id>O3</group_id>
              <group_id>O4</group_id>
            </group_id_list>
            <groups_desc>This is the mean difference of effect between active and sham in those without a history of hamstring strain.</groups_desc>
            <non_inferiority_type>Superiority</non_inferiority_type>
            <p_value>0.018</p_value>
            <method>Mixed Models Analysis</method>
            <param_type>Mean Difference (Final Values)</param_type>
            <param_value>-2.024</param_value>
            <ci_percent>95</ci_percent>
            <ci_n_sides>2-Sided</ci_n_sides>
            <ci_lower_limit>-3.4474</ci_lower_limit>
            <ci_upper_limit>-0.3406</ci_upper_limit>
          </analysis>
        </analysis_list>
      </outcome>
    </outcome_list>

    <reported_events>
      <time_frame>Data was collected on two visits separated by at least 1 week washout period. On the second visit, participants were asked about any adverse events. A survey on adverse events was sent 2 weeks after second visit asking for any information on adverse everts as well.</time_frame>
      <group_list>
        <group group_id="E1">
          <title>CLRT</title>
          <description>Subject will don protective eyewear. The hamstring reflexes are two lines on the posterior portion of the top of the head. The aperture of the laser probe will be placed at posterior end of the reflex (a), turned on and moved to the anterior end of the reflex (b) at a speed of approximately 2 cm/s. The laser will be turned off and quickly returned to point (a), turned on and moved to point (b) again. This will be repeated for a total of 30 times.</description>
        </group>
        <group group_id="E2">
          <title>SHAM</title>
          <description>The laser is inactive, all other descriptions are the same as active.</description>
        </group>
      </group_list>
      <serious_events>
        <category_list>
          <category>
            <title>Total</title>
            <event_list>
              <event>
                <sub_title>Total, all-cause mortality</sub_title>
                <counts group_id="E1" subjects_affected="0" subjects_at_risk="44"/>
                <counts group_id="E2" subjects_affected="0" subjects_at_risk="44"/>
              </event>
              <event>
                <sub_title>Total, serious adverse events</sub_title>
                <counts group_id="E1" subjects_affected="0" subjects_at_risk="44"/>
                <counts group_id="E2" subjects_affected="0" subjects_at_risk="44"/>
              </event>
            </event_list>
          </category>
        </category_list>
      </serious_events>
      <other_events>
        <frequency_threshold>0</frequency_threshold>
        <default_assessment>Systematic Assessment</default_assessment>
        <category_list>
          <category>
            <title>Total</title>
            <event_list>
              <event>
                <sub_title>Total, other adverse events</sub_title>
                <counts group_id="E1" subjects_affected="1" subjects_at_risk="44"/>
                <counts group_id="E2" subjects_affected="2" subjects_at_risk="44"/>
              </event>
            </event_list>
          </category>
          <category>
            <title>Musculoskeletal and connective tissue disorders</title>
            <event_list>
              <event>
                <sub_title>Mild soreness in Hamstring</sub_title>
                <counts group_id="E1" events="0" subjects_affected="0" subjects_at_risk="44"/>
                <counts group_id="E2" events="2" subjects_affected="2" subjects_at_risk="44"/>
              </event>
              <event>
                <sub_title>Mild Headache</sub_title>
                <counts group_id="E1" events="1" subjects_affected="1" subjects_at_risk="44"/>
                <counts group_id="E2" events="1" subjects_affected="1" subjects_at_risk="44"/>
              </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>The high baseline flexibility of the population may have a ceiling effect on the intervention. Further examination of the effects of CLRT in a clinical population is warranted.</limitations_and_caveats>
    <point_of_contact>
      <name_or_title>Nicholas Wise, DC</name_or_title>
      <organization>University of North Carolina at Chapel Hill</organization>
      <phone>(864) 494-1001</phone>
      <email>nicholas_wise@med.unc.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/NCT03044106
org study id: 16-0898
nct id: NCT03044106
lead sponsor: 
collaborator: 
collaborator: 
has dmc: No
is fda regulated drug: No
is fda regulated device: Yes
is us export: No
Purpose: To conduct a pilot study of the effect of Cranial Laser Reflex Technique (CLRT)
      compared with sham laser on hamstring muscle flexibility, strength, and pain pressure
      threshold.

      Participants: Active, young adults ages 18 to 35.

      Procedures: A two-visit, assessor and participant-blinded crossover study with 1-week
      washout. Subjects will complete three functional hamstring tests before and after CLRT and
      sham laser treatment. Subjects will also complete questionnaires to assess their expectations
      and perceptions of the interventions.
First Visit: Subjects who met the inclusion criteria and gave consent completed a brief
      questionnaire on their activity level, history of hamstring injuries, and perceived hamstring
      tightness and were randomized to one of the following for the first treatment period: 1)
      active CLRT; or 2) sham laser.

      After randomization, subjects were asked to complete the three functional hamstring tests:
      90-90 Knee Extension Angle (KEA) to assess flexibility, handheld dynamometry (HHD) for
      strength, and pain pressure threshold (PPT).

      Assessments. KEA: The 90-90 Knee Extension Angle test is a functional assessment designed to
      assess lower extremity flexibility and is considered the gold standard for hamstring length.
      The participant began in the supine position on a treatment table. The tested extremity (the
      right leg in each subject) was placed in a 90° hip and 90° knee position with the
      contralateral lower extremity placed flat on the table. A digital inclinometer was
      consistently placed at the level of the medial malleoli and the superior pole of the patella.
      The examiner maintained 90° of hip flexion. Pelvic position was monitored by palpation of the
      anterior superior iliac spine and lumbar spinous processes to maintain a neutral pelvic
      position. The examiner passively extended the knee to the point of a ''strong, but tolerable
      stretch," as reported by the subject. The examiner read the angle of the inclinometer and
      recorded the mean value of three attempts. A greater angle indicates greater degree of
      flexibility.

      Hand held Dynamometry (HHD) is currently considered a reliable and valid measurement of peak
      muscle contraction. The subject began prone on the table with right leg bent to 90°. The
      tester placed the dynamometer (microFET2; Hoggan Health Industries, Salt Lake City, UT) at
      the heel of the participant and applied force to the heel, gradually increasing in 3 to 5
      seconds. Participants was instructed to resist the applied force and maximally contract the
      hamstring muscle against the HHD device. The test ended once they are no longer able to
      resist the force and the leg begins to move (break point). The investigator recorded the mean
      value of three attempts.

      Pain Pressure Threshold (PPT) is a reliable, accurate and valid method for measuring muscle
      pain sensitivity and response to treatment. The digital algometer (FDX, Wagner Instruments,
      Greenwich, CT) is a hand-held muscle tester with a range of 0-100 lbf that consists of a
      padded disc with a diameter of 0.5" attached to a microprocessor-control unit that measures
      peak force (pounds or kilograms). The unit has a digital readout for peak-applied pressure
      and provides a built-in calibration routine that verifies a valid calibration. In order to
      determine PPT, the researcher applied the tip of the algometer to a tender spot in the
      participant's hamstrings and increased the amount of pressure until the participant verbally
      informed the researcher when the sensation of pressure became pain. At this point the
      algometer was removed and the peak force recorded. The mean of three repeated measures was
      reported.

      Intervention: Cranial Laser Reflex Technique (CLRT) is a novel complementary and alternative
      (CAM) medicine intervention for musculoskeletal conditions that incorporates principles of
      laser acupuncture with chiropractic cranial reflexology. Subjects wore protective eyewear.
      The hamstring reflexes are two lines on the posterior portion of the top of the head,
      approximately 2 cm long and 2 cm apart, running parallel to the sagittal suture. The
      posterior end of the reflexes can be located by finding the vertex, or CZ point in the
      standardized 10-20 EEG system, and moving laterally approximately 1 cm.

      The aperture of the laser probe was placed at the posterior end of the reflex (b), turned on
      and moved anteriorly to point (a) at a speed of approximately 2 cm/s. The laser was turned
      off and quickly returned to the starting point, turned on and moved again. This was repeated
      for a total of 30 times. The probe skimmed the surface of the scalp, moving aside as much
      hair as possible.

      Device: The treatment device used in this study is a Class IIIB 810nm 200 milliwatts (mW)
      near-infrared diode laser (THOR Photomedicine Ltd, Great Britain) that is currently marketed
      in the US. The laser probe is FDA-cleared and classified as a non-significant risk device.
      The spot size is 0.0364 cm^2, and the treatment time is 30 seconds. Current best-practice
      recommendations for laser acupuncture recommend a dosage between 1-4 J/cm^2 per point. Since
      the CRP is a line of 2 cm, for the purposes of calculating dosage, it was treated as a series
      of 10 connected points each with a diameter of 2mm. With the scanning rate of 2cm/s, each
      "point" on the line received 1/10 of each pass, totaling 3s (out of 30s total) exposure time
      per point. The dose per point for this intervention is calculated to be approximately 1.65
      J/cm^2.

      There was a one-week washout and the subject will return for the second treatment period.

      Primary Outcome: Hamstring flexibility (90-90 Knee Extension Angle, KEA) A clinically
      significant effect size is an increase of 5 degrees. The investigator recorded the mean value
      of three attempts. Hypothesis: CLRT will increase hamstring flexibility.

      Secondary Outcomes:

        1. Hamstring Strength as assessed by Handheld Dynamometry. HHD . The investigator recorded
           the mean value of three attempts. Hypothesis: CLRT will have a neutral to positive
           effect on hamstring strength.

        2. Pain Pressure Threshold. The mean of three repeated measures was reported. An increase
           in PPT signifies an increase in pain tolerance. Hypothesis: CLRT will increase pain
           tolerance.

        3. Age, gender, activity level, perceived hamstring tightness, perceived hamstring
           flexibility and perceived hamstring strength were assessed at baseline and subsequent
           follow up visit. Results were stratified by these variables to assess interaction with
           treatment.

      Sample Size and Power: Based on previously published results, a mean increase of 5º on the
      KEA (e.g., from 135º to 140º) is considered to be clinically meaningful, assuming a common
      standard deviation of 15º. It is also assumed that correlation between repeated measurements
      from the same individual will be at least 0.75 (likely a conservative assumption). Under
      these assumptions, enrolling 38 participants would provide at least 80% power using a
      two-sided test at the 0.05 level.
allocation: Randomized
intervention model: Crossover Assignment
intervention model description: Subjects who meet the inclusion criteria and give consent were randomized to one of the following for the first treatment period: 1) active CLRT; or 2) sham laser. At the first intervention visit, the research assistant entered the subject's assigned identification into an online computer program (selected by study biostatistician) to determine assignment to one of the two periods. The study biostatistician used computer-generated random numbers to generate the allocation sequence using random blocks of random sizes. A one-week washout period minimized carryover effects.
primary purpose: Treatment
masking: Double (Participant, Outcomes Assessor)
masking description: Subjects and assessors were blinded to treatment allocation. The subject was face down, eyes closed, and wearing protective eyewear that blocks the specific wavelength of the laser light during the intervention.
After each treatment session, the participants completed a de-blinding questionnaire administrated by the assessor providing a dichotomous 'yes' or 'no' answer as to whether active treatment was received. This response was followed by a second question regarding how certain they were that active treatment was received on a 0-10 numeric rating scale (NRS), where 0 represents absolutely uncertain and 10 represents absolutely certain.
measure: 90-90 Knee Extension Angle Test
time frame: At baseline and immediately after intervention
description: Knee Extension Angle (KEA) test is a functional test designed to assess lower extremity flexibility and is considered the gold standard test for assessing hamstring length. Results will be recorded as degrees of knee flexion angle. A clinically significant effect size is an increase of 5 degrees.
measure: Handheld Dynamometry
time frame: At baseline and immediately after intervention
description: Handheld Dynamometry (HHD) is measures peak muscle contraction. The measurements will be recorded as kilograms (kg) and higher scores indicate higher muscle strength. The subject will be prone on the table with right leg bent to 90° and will maximally contract the hamstring muscle for 4-5 seconds against the HHD device. The investigator will record the mean value of three attempts. Higher scores indicate greater strength.
measure: Pain Pressure Threshold
time frame: At baseline and immediately after intervention
description: PPT is a reliable, accurate and valid method for measuring muscle pain sensitivity and response to treatment. In order to determine PPT, the researcher will apply the tip of the algometer to a tender spot in the participant's hamstrings and increase the amount of pressure until the participant verbally informs the researcher when the sensation of pressure became pain. At this point the algometer is removed and the peak force recorded. The mean of three repeated measures will be reported. An increase in PPT signifies an increase in pain tolerance and a decrease in pain sensitivity.
measure: Mean Difference Pre/Post KEA, Stratified by History of Prior Hamstring Strain
time frame: At baseline and immediately after intervention
description: Mean difference between active CLRT and Sham in hamstring flexibility (KEA) stratified by a history of prior hamstring injury. 8 participants reported prior injuries, 36 reported having no prior hamstring strain.
arm group label: CLRT, Then Sham
arm group type: Active Comparator
description: Subjects performed the KEA, HHD, PPT functional tests on their right hamstring before and after the CLRT intervention.
arm group label: Sham, Then CLRT
arm group type: Sham Comparator
description: The Sham procedure was identical to CLRT except the laser device was placed in placebo mode: all device indicator lights and sounds will be functional but no laser light will be emitted from probe aperture.
intervention type: Device
intervention name: CLRT
description: CLRT is a novel method of laser stimulation on specific cranial reflex points that modulate muscle tone.
arm group label: CLRT, Then Sham
arm group label: Sham, Then CLRT
other name: Cranial Laser Reflex Technique
criteria: 
gender: All
minimum age: 18 Years
maximum age: 35 Years
healthy volunteers: Accepts Healthy Volunteers
last name: Nicholas A Wise, D.C.
role: Principal Investigator
affiliation: University of North Carolina, Chapel Hill
facility: 
country: United States
responsible party type: Sponsor
mesh term: Muscle Weakness
mesh term: Myalgia
mesh term: Muscle Hypertonia
sharing ipd: No
provided document: 
participant flow: 
baseline: 
outcome list: 
reported events: 
certain agreements: 
limitations and caveats: The high baseline flexibility of the population may have a ceiling effect on the intervention. Further examination of the effects of CLRT in a clinical population is warranted.
point of contact: 