Hamstring Tightness

Study Overview
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Brief Summary
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The purpose of this study is to find out if individuals with tight hamstring muscles who receive dry needling in addition to a standard stretching exercise program, show an improvement in hamstring tightness and function compared to individuals with tight hamstrings who receive either sham dry needling or no needling (blunt needle) in addition to a standard stretching program.

Detailed Description
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Tightness of the hamstring muscles is a risk factor for injury. Currently, there is no data on the effect of dry needling on hamstring extensibility or functional performance measures among asymptomatic individuals with hamstring muscle tightness. The investigator wants to assess if individuals with tight hamstring muscles who receive dry needling in addition to a standard stretching exercise program, exhibit reduced hamstring tightness and improved functional performance compared to individuals with tight hamstrings who receive either sham dry needling or no needling (blunt needle) in addition to a standard stretching program.

Official Title
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Clinical Effects of Dry Needling Among Asymptomatic Individuals With Hamstring Tightness

Conditions
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Hamstring Tightness

Intervention / Treatment
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* Procedure: Dry needling
* Procedure: Sham needling
* Procedure: Blunt needle placement
* Other: Standard hamstring stretching exercise


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Hamstring 90/90 extensibility goniometric measurement of more than 20 degrees of knee flexion bilaterally Ability to perform a squat to 90 degrees of knee flexion without assistance of the upper extremities Asymptomatic during walking Exclusion Criteria: History of systemic neurological or arthritic condition History of bony or peripheral nerve trauma or surgery lower extremities History of treatment with dry needling No contraindications to dry needling

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Dry needling group<br>Subjects with tight hamstrings will receive dry needling to the hamstrings with the needle inserted into the muscle tissue in addition to a standard hamstring stretching exercise program. | Procedure: Dry needling<br>* Dry needling will be performed on two points over the hamstring muscles on the randomly determined side. Points 2 cm distal to the ischial tuberosity and halfway between the ischial tuberosity and popliteal crease within the medial and lateral muscle bellies will be identified and the skin cleansed with rubbing alcohol. A Seirin L- type 50 mm needle will be inserted into each of the two points to a depth no greater than three-quarters length of the needle into the hamstring muscle for 30 seconds using a vertical pistoning technique and then statically up to 10 minutes.<br>Other: Standard hamstring stretching exercise<br>* Subjects will be instructed to stretch the back of their thighs, once a day for 3 repetitions, holding for 30 seconds each time performed bilaterally.<br>|
| Sham Comparator: Sham dry needling group<br>Subjects with tight hamstrings will receive sham dry needling to the hamstrings with the needle inserted into the subcutaneous tissue in addition to a standard hamstring stretching exercise program. | Procedure: Sham needling<br>* Sham dry needling will be performed on two points over the hamstring muscles on the randomly determined side. Points 2 cm distal to the ischial tuberosity and halfway between the ischial tuberosity and popliteal crease within the medial and lateral muscle bellies will be identified and the skin cleansed with rubbing alcohol. The plastic tube of a Seirin L- type 50 mm needle will be placed against the skin and the needle will be tapped once so that it is inserted subcutaneously no deeper than 5 mm for 30 seconds using a vertical pistoning technique and then statically up to 10 minutes in each location.<br>Other: Standard hamstring stretching exercise<br>* Subjects will be instructed to stretch the back of their thighs, once a day for 3 repetitions, holding for 30 seconds each time performed bilaterally.<br>|
| Placebo Comparator: No needling group<br>Subjects with tight hamstrings will receive no needling but have the tip of a blunt needle handle placed on the skin over the hamstrings in addition to a standard hamstring stretching exercise program. | Procedure: Blunt needle placement<br>* Blunt needle placement will be performed on two points over the hamstring muscles on the randomly determined side. Points 2 cm distal to the ischial tuberosity and halfway between the ischial tuberosity and popliteal crease within the medial and lateral muscle bellies will be identified and the skin cleansed with rubbing alcohol. A blunt needle handle is inserted into a plastic tube which will be placed over the identified points for 30 seconds and then for an additional 10 minutes each. The blunt needle handle only touches the skin without puncturing it.<br>Other: Standard hamstring stretching exercise<br>* Subjects will be instructed to stretch the back of their thighs, once a day for 3 repetitions, holding for 30 seconds each time performed bilaterally.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in hamstring muscle extensibility | Bilateral 90/90 hamstring muscle extensibility passive range of motion (PROM) measurements will be assessed using a goniometer. The goniometer measures the angle of the joint at both extremes of the range of motion (ROM). An increase in the passive range of motion (PROM) indicates increased hamstring muscle extensibility. | Baseline, at 5 weeks from baseline | 
| Change in unilateral hop for distance test scores | The functional performance of the hamstring muscles will be assessed by using the unilateral hop for distance test. The subjects will be instructed to stand on the leg to be tested and hop and land on the same limb. The distance hopped, measured at the level of the great toe, will be measured (centimeters). Scores will be recorded as absolute distance (in centimeters). An increase in the score (distance covered) from baseline to 5 weeks from baseline indicates better functional performance of the hamstrings. | Baseline, at 5 weeks from baseline | 
| Change in crossover hop for distance tests scores | The functional performance of the hamstring muscles will be assessed by using the crossover hop for distance test. The subjects will be instructed to hop forward 3 times while alternately crossing over a marking. The total distance hopped forward will be recorded. The heel of the hop leg will be used to determine the length of the jump. Crossover hop limb symmetry index (LSI) scores for knee function within normal ranges are generally greater than 95%. An increase in the crossover hop limb symmetry index (LSI) from baseline to 5 weeks from baseline indicates better functional performance of the hamstrings. | Baseline, at 5 weeks from baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in dynamometry pressure readings | The strength of the hamstrings will be assessed using a hand-held dynamometer.The subjects will be asked to exert maximal force against the dynamometer and the reading is recorded. Scores are based on force production in kilograms or pounds; kilograms (0-90), pounds (0-200). Higher pressure scores indicate better muscle strength of the hamstring muscles. | Baseline, at 5 weeks from baseline | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Dry needling