Hamstring Strain in High School Athletes

Comparative Effectiveness of Hamstring Muscle Strain Injury Prevention Programs

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.

Study Overview

• Status: Completed
• Conditions: Strains Thigh
• Intervention / Treatment: Other: Stretching; Other: Strengthening; Other: Neuromuscular

Detailed Description

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.

• Study Type: Interventional
• Enrollment (Actual): 196
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Minnesota
    • Rochester, Minnesota, United States, 55405
      • Mayo Clinic in Rochester

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 14 years to 18 years (ADULT, CHILD)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion criteria:

• member of high school basketball team
• school agreement to participate in study

Exclusion criteria:

• inability to ambulate independently
• lower extremity or back surgery within 1 year of study enrollment
• presence of neurological disease

Study Plan

How is the study designed?

Design Details

• Primary Purpose: PREVENTION
• Allocation: RANDOMIZED
• Interventional Model: PARALLEL
• Masking: SINGLE

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
EXPERIMENTAL: Flexibility; Stretching exercise	Other: Stretching; Lower extremity flexibility exercises will be performed
EXPERIMENTAL: Strength; Eccentric hamstring strengthening exercise	Other: Strengthening; Eccentric hamstring strengthening exercises will be performed
EXPERIMENTAL: Neuromuscular; Balance exercise	Other: Neuromuscular; Dynamic lower extremity balance and movement control exercises will be performed
NO_INTERVENTION: Control; No exercise

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of subjects who sustain a hamstring strain	Physician based diagnosis	Duration of school basketball season, approximately 4 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in thigh strength	This will be measured using an isokinetic dynamometer	Baseline and post school basketball season, approximately 4 months
Change in hamstring stiffness	This will be measured using sheer wave elastography	Baseline, post school basketball season, approximately 4 months
Change in lower extremity power	This will be measured using force plates	Baseline, post school basketball season, approximately 4 months
Change in lower extremity hamstring flexibility	Measured using a goniometer	Baseline, post school basketball season, approximately 4 months

Collaborators and Investigators

• Sponsor: Mayo Clinic
• Collaborators: General Electric; TRIA Orthopaedic Center
• Investigators: Principal Investigator: Nathan Schilaty, DC, PhD, Mayo Clinic

Publications and helpful links

Helpful Links

• Mayo Clinic Clinical Trials

Study record dates

Study Major Dates

• Study Start (ACTUAL): September 27, 2017
• Primary Completion (ACTUAL): June 10, 2020
• Study Completion (ACTUAL): August 31, 2021

Study Registration Dates

• First Submitted: August 10, 2017
• First Submitted That Met QC Criteria: August 10, 2017
• First Posted (ACTUAL): August 14, 2017

Study Record Updates

• Last Update Posted (ACTUAL): October 4, 2021
• Last Update Submitted That Met QC Criteria: September 27, 2021
• Last Verified: September 1, 2021

More Information

Terms related to this study

• Keywords: ultrasound; intervention; hamstring
• Additional Relevant MeSH Terms: Wounds and Injuries; Sprains and Strains
• Other Study ID Numbers: 17-003905

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Subject identification (ID) and study data (test results, injuries) will be shared with study co-investigators at TRIA Orthopaedics
• IPD Sharing Time Frame: Co-Investigators will have access to the data as it is collected, for the duration of the study.
• IPD Sharing Access Criteria: Secured file transfer protocols will be utilized to transfer files between investigators. Only study co-investigators may access study data.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; ICF; CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No