<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/NCT03248011</url>
  </required_header>
  <id_info>
    <org_study_id>17-003905</org_study_id>
    <nct_id>NCT03248011</nct_id>
  </id_info>
  <brief_title>Hamstring Strain in High School Athletes</brief_title>
  <official_title>Comparative Effectiveness of Hamstring Muscle Strain Injury Prevention Programs</official_title>
  <sponsors>
    <lead_sponsor>
      <agency>Mayo Clinic</agency>
      <agency_class>Other</agency_class>
    </lead_sponsor>
    <collaborator>
      <agency>General Electric</agency>
      <agency_class>Industry</agency_class>
    </collaborator>
    <collaborator>
      <agency>TRIA Orthopaedic Center</agency>
      <agency_class>Other</agency_class>
    </collaborator>
  </sponsors>
  <source>Mayo Clinic</source>
  <oversight_info>
    <has_dmc>No</has_dmc>
    <is_fda_regulated_drug>No</is_fda_regulated_drug>
    <is_fda_regulated_device>No</is_fda_regulated_device>
  </oversight_info>
  <brief_summary>
    <textblock>
      The purpose of the current study is, 1) Determine the effectiveness of injury prevention&#xD;
      programs for prevention of hamstring muscle strains, 2) Identify how these programs impact&#xD;
      athletes' flexibility, muscle stiffness, strength, and power, and 3) Determine the ability of&#xD;
      a state-of-the-art imaging technology, shear wave elastography to predict future hamstring&#xD;
      muscle strain injury.&#xD;
    </textblock>
  </brief_summary>
  <detailed_description>
    <textblock>
      Hamstring strains are a significant problem for basketball athletes across levels of play for&#xD;
      both sexes. The impact of hamstring muscle strains (HSMS) is significant. Injuries typically&#xD;
      result in persistent symptoms and lengthy recovery periods which limit the athlete's practice&#xD;
      and play time. Even more significantly, HSMS have high rates of reinjury. It is estimated&#xD;
      that approximately one-third of hamstring strains are recurrent. Given the high incidence of&#xD;
      HSMS and the substantial tendency for injuries to recur, it has been advocated the greatest&#xD;
      impact may be achieved by the development of improved techniques for prevention of initial&#xD;
      injury.&#xD;
&#xD;
      Multiple risk factors for HSMS have been identified. Perhaps the strongest modifiable risk&#xD;
      factor associated with HSMS is an imbalance between quadriceps and hamstring strength,&#xD;
      specifically the eccentric hamstrings and concentric quadriceps strength ratio. The rationale&#xD;
      is that sufficient eccentric capacity of the hamstring muscles is necessary to offset the&#xD;
      concentric quadriceps contraction during the terminal swing phase of running. Not&#xD;
      surprisingly, prevention programs that emphasize eccentric hamstring strengthening have been&#xD;
      effective in reduction of HSMS injury rates.Prospective studies have demonstrated mixed&#xD;
      results regarding the relationship between hamstring flexibility and hamstring injury, and&#xD;
      the effectiveness of a flexibility program for reduction of the incidence of HSMS remains&#xD;
      controversial. Stretching duration, frequency, timing of stretching relative to sports&#xD;
      activities and the type of stretch being performed have been suggested as important factors&#xD;
      in the effectiveness of a flexibility program at reducing injury occurrence. In addition,&#xD;
      reduced hip flexor and quadriceps flexibility has been identified as a risk factor for HSMS.&#xD;
      Further investigation is necessary to determine if a flexibility program that addresses both&#xD;
      anterior and posterior thigh musculature reduces injury risk. The role of neuromuscular (NM)&#xD;
      deficits as a risk factor in HSMS injuries is unclear. Inclusion of NM exercises in a six&#xD;
      week training period improved lower extremity control and movement discrimination, which has&#xD;
      been suggested to contribute to HSMS injury prevention. However, the impact of a NM injury&#xD;
      prevention program on HSMS rates has not been established.&#xD;
&#xD;
      Sheer wave elastography (SWE) represents an emerging imaging technology. This real-time&#xD;
      imaging technique evaluates the local mechanical properties of muscles. Thus, SWE has the&#xD;
      potential to provide more sensitive insight into muscle stiffness than flexibility&#xD;
      assessment. Recent studies have utilized this technique to evaluate the effect of lower&#xD;
      extremity positioning on hamstring stiffness. The relationship between stiffness measures&#xD;
      obtained using SWE and HSMS has not, however, been established.&#xD;
&#xD;
      Key gaps in knowledge regarding HSMS injury prevention programs remain. Most critically, the&#xD;
      effectiveness of HSMS prevention programs among basketball athletes is unknown. Furthermore,&#xD;
      the comparative effectiveness of eccentric, flexibility, and NM training for reduction of&#xD;
      HSMS injuries is also unknown. Assessment of lower extremity strength, rate of power&#xD;
      production, flexibility, and stiffness (captured with SWE) may elucidate the mechanisms&#xD;
      underlying the effectiveness of injury prevention training, and aid in enhancement of injury&#xD;
      prevention programs. Thus, the potential impact of this proposal is profound as our&#xD;
      investigative team aims to fill these gaps in knowledge. Ultimately, the results of this&#xD;
      study have the potential to 1) reduce injuries among basketball athletes and consequently&#xD;
      enhance and lengthen athletic careers, 2) provide scientific rationale underlying the effects&#xD;
      of HSMS injury prevention training, and 3) determine if a novel ultrasound imaging technique&#xD;
      may be effective in determining risk for HSMS.&#xD;
    </textblock>
  </detailed_description>
  <overall_status>Completed</overall_status>
  <start_date type="Actual">September 27, 2017</start_date>
  <completion_date type="Actual">August 31, 2021</completion_date>
  <primary_completion_date type="Actual">June 10, 2020</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>Parallel Assignment</intervention_model>
    <intervention_model_description>This is a prospective, randomized, repeated measures single- blind clinical trial.</intervention_model_description>
    <primary_purpose>Prevention</primary_purpose>
    <masking>Single (Investigator)</masking>
    <masking_description>Group assignment will be masked to investigator.</masking_description>
  </study_design_info>
  <primary_outcome>
    <measure>Number of subjects who sustain a hamstring strain</measure>
    <time_frame>Duration of school basketball season, approximately 4 months</time_frame>
    <description>Physician based diagnosis</description>
  </primary_outcome>
  <secondary_outcome>
    <measure>Change in thigh strength</measure>
    <time_frame>Baseline and post school basketball season, approximately 4 months</time_frame>
    <description>This will be measured using an isokinetic dynamometer</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Change in hamstring stiffness</measure>
    <time_frame>Baseline, post school basketball season, approximately 4 months</time_frame>
    <description>This will be measured using sheer wave elastography</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Change in lower extremity power</measure>
    <time_frame>Baseline, post school basketball season, approximately 4 months</time_frame>
    <description>This will be measured using force plates</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Change in lower extremity hamstring flexibility</measure>
    <time_frame>Baseline, post school basketball season, approximately 4 months</time_frame>
    <description>Measured using a goniometer</description>
  </secondary_outcome>
  <number_of_arms>4</number_of_arms>
  <enrollment type="Actual">196</enrollment>
  <condition>Strains Thigh</condition>
  <arm_group>
    <arm_group_label>Flexibility</arm_group_label>
    <arm_group_type>Experimental</arm_group_type>
    <description>Stretching exercise</description>
  </arm_group>
  <arm_group>
    <arm_group_label>Strength</arm_group_label>
    <arm_group_type>Experimental</arm_group_type>
    <description>Eccentric hamstring strengthening exercise</description>
  </arm_group>
  <arm_group>
    <arm_group_label>Neuromuscular</arm_group_label>
    <arm_group_type>Experimental</arm_group_type>
    <description>Balance exercise</description>
  </arm_group>
  <arm_group>
    <arm_group_label>Control</arm_group_label>
    <arm_group_type>No Intervention</arm_group_type>
    <description>No exercise</description>
  </arm_group>
  <intervention>
    <intervention_type>Other</intervention_type>
    <intervention_name>Stretching</intervention_name>
    <description>Lower extremity flexibility exercises will be performed</description>
    <arm_group_label>Flexibility</arm_group_label>
  </intervention>
  <intervention>
    <intervention_type>Other</intervention_type>
    <intervention_name>Strengthening</intervention_name>
    <description>Eccentric hamstring strengthening exercises will be performed</description>
    <arm_group_label>Strength</arm_group_label>
  </intervention>
  <intervention>
    <intervention_type>Other</intervention_type>
    <intervention_name>Neuromuscular</intervention_name>
    <description>Dynamic lower extremity balance and movement control exercises will be performed</description>
    <arm_group_label>Neuromuscular</arm_group_label>
  </intervention>
  <eligibility>
    <criteria>
      <textblock>
        Inclusion criteria:&#xD;
&#xD;
          -  member of high school basketball team&#xD;
&#xD;
          -  school agreement to participate in study&#xD;
&#xD;
        Exclusion criteria:&#xD;
&#xD;
          -  inability to ambulate independently&#xD;
&#xD;
          -  lower extremity or back surgery within 1 year of study enrollment&#xD;
&#xD;
          -  presence of neurological disease&#xD;
      </textblock>
    </criteria>
    <gender>All</gender>
    <minimum_age>14 Years</minimum_age>
    <maximum_age>18 Years</maximum_age>
    <healthy_volunteers>No</healthy_volunteers>
  </eligibility>
  <overall_official>
    <last_name>Nathan Schilaty, DC, PhD</last_name>
    <role>Principal Investigator</role>
    <affiliation>Mayo Clinic</affiliation>
  </overall_official>
  <location>
    <facility>
      <name>Mayo Clinic in Rochester</name>
      <address>
        <city>Rochester</city>
        <state>Minnesota</state>
        <zip>55405</zip>
        <country>United States</country>
      </address>
    </facility>
  </location>
  <location_countries>
    <country>United States</country>
  </location_countries>
  <link>
    <url>https://www.mayo.edu/research/clinical-trials</url>
    <description>Mayo Clinic Clinical Trials</description>
  </link>
  <verification_date>September 2021</verification_date>
  <study_first_submitted>August 10, 2017</study_first_submitted>
  <study_first_submitted_qc>August 10, 2017</study_first_submitted_qc>
  <study_first_posted type="Actual">August 14, 2017</study_first_posted>
  <last_update_submitted>September 27, 2021</last_update_submitted>
  <last_update_submitted_qc>September 27, 2021</last_update_submitted_qc>
  <last_update_posted type="Actual">October 4, 2021</last_update_posted>
  <responsible_party>
    <responsible_party_type>Principal Investigator</responsible_party_type>
    <investigator_affiliation>Mayo Clinic</investigator_affiliation>
    <investigator_full_name>Nathan D. Schilaty</investigator_full_name>
    <investigator_title>Principal Investigator</investigator_title>
  </responsible_party>
  <keyword>hamstring</keyword>
  <keyword>ultrasound</keyword>
  <keyword>intervention</keyword>
  <condition_browse>
    <!-- CAUTION:  The following MeSH terms are assigned with an imperfect algorithm            -->
    <mesh_term>Sprains and Strains</mesh_term>
  </condition_browse>
  <patient_data>
    <sharing_ipd>Yes</sharing_ipd>
    <ipd_description>Subject identification (ID) and study data (test results, injuries) will be shared with study co-investigators at TRIA Orthopaedics</ipd_description>
    <ipd_info_type>Study Protocol</ipd_info_type>
    <ipd_info_type>Informed Consent Form (ICF)</ipd_info_type>
    <ipd_info_type>Clinical Study Report (CSR)</ipd_info_type>
    <ipd_time_frame>Co-Investigators will have access to the data as it is collected, for the duration of the study.</ipd_time_frame>
    <ipd_access_criteria>Secured file transfer protocols will be utilized to transfer files between investigators. Only study co-investigators may access study data.</ipd_access_criteria>
  </patient_data>
  <!-- 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/NCT03248011
org study id: 17-003905
nct id: NCT03248011
lead sponsor: 
collaborator: 
collaborator: 
has dmc: No
is fda regulated drug: No
is fda regulated device: No
The purpose of the current study is, 1) Determine the effectiveness of injury prevention
      programs for prevention of hamstring muscle strains, 2) Identify how these programs impact
      athletes' flexibility, muscle stiffness, strength, and power, and 3) Determine the ability of
      a state-of-the-art imaging technology, shear wave elastography to predict future hamstring
      muscle strain injury.
Hamstring strains are a significant problem for basketball athletes across levels of play for
      both sexes. The impact of hamstring muscle strains (HSMS) is significant. Injuries typically
      result in persistent symptoms and lengthy recovery periods which limit the athlete's practice
      and play time. Even more significantly, HSMS have high rates of reinjury. It is estimated
      that approximately one-third of hamstring strains are recurrent. Given the high incidence of
      HSMS and the substantial tendency for injuries to recur, it has been advocated the greatest
      impact may be achieved by the development of improved techniques for prevention of initial
      injury.

      Multiple risk factors for HSMS have been identified. Perhaps the strongest modifiable risk
      factor associated with HSMS is an imbalance between quadriceps and hamstring strength,
      specifically the eccentric hamstrings and concentric quadriceps strength ratio. The rationale
      is that sufficient eccentric capacity of the hamstring muscles is necessary to offset the
      concentric quadriceps contraction during the terminal swing phase of running. Not
      surprisingly, prevention programs that emphasize eccentric hamstring strengthening have been
      effective in reduction of HSMS injury rates.Prospective studies have demonstrated mixed
      results regarding the relationship between hamstring flexibility and hamstring injury, and
      the effectiveness of a flexibility program for reduction of the incidence of HSMS remains
      controversial. Stretching duration, frequency, timing of stretching relative to sports
      activities and the type of stretch being performed have been suggested as important factors
      in the effectiveness of a flexibility program at reducing injury occurrence. In addition,
      reduced hip flexor and quadriceps flexibility has been identified as a risk factor for HSMS.
      Further investigation is necessary to determine if a flexibility program that addresses both
      anterior and posterior thigh musculature reduces injury risk. The role of neuromuscular (NM)
      deficits as a risk factor in HSMS injuries is unclear. Inclusion of NM exercises in a six
      week training period improved lower extremity control and movement discrimination, which has
      been suggested to contribute to HSMS injury prevention. However, the impact of a NM injury
      prevention program on HSMS rates has not been established.

      Sheer wave elastography (SWE) represents an emerging imaging technology. This real-time
      imaging technique evaluates the local mechanical properties of muscles. Thus, SWE has the
      potential to provide more sensitive insight into muscle stiffness than flexibility
      assessment. Recent studies have utilized this technique to evaluate the effect of lower
      extremity positioning on hamstring stiffness. The relationship between stiffness measures
      obtained using SWE and HSMS has not, however, been established.

      Key gaps in knowledge regarding HSMS injury prevention programs remain. Most critically, the
      effectiveness of HSMS prevention programs among basketball athletes is unknown. Furthermore,
      the comparative effectiveness of eccentric, flexibility, and NM training for reduction of
      HSMS injuries is also unknown. Assessment of lower extremity strength, rate of power
      production, flexibility, and stiffness (captured with SWE) may elucidate the mechanisms
      underlying the effectiveness of injury prevention training, and aid in enhancement of injury
      prevention programs. Thus, the potential impact of this proposal is profound as our
      investigative team aims to fill these gaps in knowledge. Ultimately, the results of this
      study have the potential to 1) reduce injuries among basketball athletes and consequently
      enhance and lengthen athletic careers, 2) provide scientific rationale underlying the effects
      of HSMS injury prevention training, and 3) determine if a novel ultrasound imaging technique
      may be effective in determining risk for HSMS.
allocation: Randomized
intervention model: Parallel Assignment
intervention model description: This is a prospective, randomized, repeated measures single- blind clinical trial.
primary purpose: Prevention
masking: Single (Investigator)
masking description: Group assignment will be masked to investigator.
measure: Number of subjects who sustain a hamstring strain
time frame: Duration of school basketball season, approximately 4 months
description: Physician based diagnosis
measure: Change in thigh strength
time frame: Baseline and post school basketball season, approximately 4 months
description: This will be measured using an isokinetic dynamometer
measure: Change in hamstring stiffness
time frame: Baseline, post school basketball season, approximately 4 months
description: This will be measured using sheer wave elastography
measure: Change in lower extremity power
time frame: Baseline, post school basketball season, approximately 4 months
description: This will be measured using force plates
measure: Change in lower extremity hamstring flexibility
time frame: Baseline, post school basketball season, approximately 4 months
description: Measured using a goniometer
arm group label: Flexibility
arm group type: Experimental
description: Stretching exercise
arm group label: Strength
arm group type: Experimental
description: Eccentric hamstring strengthening exercise
arm group label: Neuromuscular
arm group type: Experimental
description: Balance exercise
arm group label: Control
arm group type: No Intervention
description: No exercise
intervention type: Other
intervention name: Stretching
description: Lower extremity flexibility exercises will be performed
arm group label: Flexibility
intervention type: Other
intervention name: Strengthening
description: Eccentric hamstring strengthening exercises will be performed
arm group label: Strength
intervention type: Other
intervention name: Neuromuscular
description: Dynamic lower extremity balance and movement control exercises will be performed
arm group label: Neuromuscular
criteria: 
gender: All
minimum age: 14 Years
maximum age: 18 Years
healthy volunteers: No
last name: Nathan Schilaty, DC, PhD
role: Principal Investigator
affiliation: Mayo Clinic
facility: 
country: United States
url: https://www.mayo.edu/research/clinical-trials
description: Mayo Clinic Clinical Trials
responsible party type: Principal Investigator
investigator affiliation: Mayo Clinic
investigator full name: Nathan D. Schilaty
investigator title: Principal Investigator
mesh term: Sprains and Strains
sharing ipd: Yes
ipd description: Subject identification (ID) and study data (test results, injuries) will be shared with study co-investigators at TRIA Orthopaedics
ipd info type: Study Protocol
ipd info type: Informed Consent Form (ICF)
ipd info type: Clinical Study Report (CSR)
ipd time frame: Co-Investigators will have access to the data as it is collected, for the duration of the study.
ipd access criteria: Secured file transfer protocols will be utilized to transfer files between investigators. Only study co-investigators may access study data.