6

Brief resume of the intended work:

6.1 Need for the Study:

“Sports injuries “are injuries that happen when playing sports or exercising. Some are

from accidents. Others can result from poor training practices or improper gear.1,2,3

Sports injuries can be classified into: - (a) Acute (b) Chronic injury. Acute injuries

occur suddenly when playing or exercising. Sprained ankles, strained backs, and

fractured hands. Signs of acute injury include: - sudden severe pain, swelling, not being

able to place weight on leg, knee, ankle, foot, arm, elbow wrist, hand and finger.1

Chronic injuries happen after you play a sport or exercise for a long time. Signs of

chronic injury include: - pain when you play, pain when you exercise, a dull ache when

you rest and swelling.1

Hamstring muscle strain injury is one of the most commonly seen injuries in sports that

involve sprinting such as track and field.4 Many predisposing factors for hamstrings

strain have been suggested in literature, including insufficient warm up, poor flexibility,

muscle imbalances, muscle weakness, fatigued – synergic contraction of muscle group

and previous injury.5-6 Most studies suggest that hamstrings strain occurs during the

later part of swing phase when the hamstrings are working to decelerate knee extension

and the muscle develops tension while lengthening.4-6 The biceps femoris (53%) was the

most commonly strained muscle of the hamstrings complex.4-5 Recent MRI studies on

hamstrings strain injuries demonstrated that over 90% of hamstrings strain injuries

occurred at the muscle belly or musculo-tendinous junction.4, 6

Rates of hamstrings injury vary by differing injury definitions and sporting

populations.Prevalance rates vary from 8% to 25 %.7 Recent studies reported that

hamstrings strain injuries account for 12-16% of all injuries in Australian professional

football (Arnason et al 2004), 12% of all injuries in soccer (Woods et al 2004), and 6-

1

15% in rugby (Brooks et al 2006).4

Clinically hamstrings injuries are usually characterized by a history of a sudden onset of

posterior thigh pain associated with localized tenderness and loss of function. On

examination there may be localized swelling, tenderness and possibly a palpable

defect .Ecchymosis is highly indicative of a significant injury. Athletes with chronic

injuries often describe a feeling of tightness or an impending pull. There is also a

reduced straight leg raise when compared with uninjured side.8 Grade 1 injuries signify

a small tear of the muscle or tendon, minor swelling, and pain. Grade II strains are more

complete partial tears, with definite loss of strength and pain. Grade III are complete

ruptures of the musculotendinous unit with a complete loss of muscle function.7

Management of hamstrings strain is divided into five phases:- Phase I (Acute) 1-7

days:-the most used treatment in muscle strains, including hamstrings strains, in the

acute phase is rest , ice, compression and elevation regimen. The goal of this treatment

is to control hemorrhaging and minimize inflammation and pain. Other non –operative

measures include the use of non-steroidal anti inflammatory medication, intramuscular

injection of corticosteroid, electrical stimulation and ultrasound. Surgery is occasionally

indicated where there is complete avulsion. Phase II (sub acute) day 3 to 3 weeks:-This

phase begins when the signs of inflammation (swelling, redness, heat and pain) begin to

resolve.

In this phase it is important to continue muscle action to prevent atrophy, maintain

flexibility and promote healing. Regular concentric strength exercises can begin in this

phase when the athlete has achieved full range of motion without pain. 6, 7

Stretching is a technique used to lengthen shortened soft tissues at the musculotendinous

units to facilitate an increase in ROM. Stretching has an impact on both contractile and

non-contractile soft tissues. Types are Static, Dynamic, Ballistic, PNF (Contract relax,

2

Hold relax, Slow reversal –contract relax, rhythmic initiation).9 Hamstrings stretching

are popular among physical therapists, athletic trainer and coaching professionals, who

all have interest in improving flexibility in both symptomatic and asymptomatic

clientele.10 Conventionally Dynamic stretching is better than static stretching –

According to Trent J. Herda et al that results of study indicated that the static stretching

decreased isometric PT of the hamstrings muscles at the knee joint angles of 101o and

81o but there were no changes in strength as a result of the Dynamic stretching.11 Jose

Shelton et al stated that dynamic stretching increases core muscle temperature elongates

muscle and stimulates the nervous system and decreases chances of injury and dynamic

stretching increases flexibility as well as muscle power.12 Thomas Little et al stated that

dynamic stretching is beneficial than static stretching for professional soccer players in

vertical jump tests, pre competition warm ups, and probably optimal for high speed

performances such as soccer.13

Dynamic stretching consists of functional based exercises which use sport specific

movements to prepare the body for movement. It consists of controlled arm and leg

swings that are taken gently to the limits of (range of motion) ROM.The effectiveness

of dynamic stretching, as it increases core temperature, muscle temperature, elongation

of muscles and stimulates nervous system and decreases chances of injury.12-13 This

technique is most controversial stretching method because it can cause the most

soreness and injury, increases muscular tension and it fails to produce adequate time for

the tissues to adapt to the stretch.

Muscle energy technique (MET) is a manual technique developed by osteopaths and

now used in many different manual therapy professionals. This is also known as active

muscular relaxation technique. It is claimed to be effective for a variety of purposes

including lengthening a shortened muscles, as a lymphatic or venous pump to aid the

drainage of fluid or blood and increasing the range of motion.14 Leon Chaitow et al

3

MET is quite safe. Occasionally some muscle stiffness and soreness after treatment. If

the area being treated is not localized well or if too much contractile force is used pain

may be increased.

Mohd. Waseem et al. concluded that MET is significantly improving the hamstrings

flexibility. (Range of motion) in collegiate males. Gary Fryer et al demonstrated that a

single application of Muscle energy Technique (MET) produced an increase in passive

stretch of the hamstring muscle. This observed change in range of motion is possibly

due to an increased tolerance to stretch.14

If beginners to MET: Stay within the very simple guideline which states categorically

cause no pain when using MET stick to light (20% of strength) contraction do not

stretch over- enthusiastically , but only take muscles a short way past their restriction

barrier when stretching have the patient assist in this stretch.

Studies have shown that Dynamic stretching is effective in increasing the vertical jump

height.12 Another study showed that dynamic stretching is also optimal for high-speed

performances required in sports such as soccer. Dynamic stretching increases flexibility,

increases blood flow, elevates core or peripheral temperature, increase the sensitivity of

nerve receptors and increase the speed of nerve impulses, potentially encouraging

muscle contractions to be more rapid and powerful.12-13 Moreover studies have shown

that muscle energy technique is effective in increasing Hamstring muscle flexibility

however the study was done in normal collegiate males.14 Another study has shown that

Muscle Energy Technique produced an immediate increase in passive knee extension in

normal subjects.15 It is also effective in reducing low back ache, effective in lumbar

strain, increasing range of motion.14,15 However it is not yet known that whether Muscle

energy technique and Dynamic stretching can increase flexibility in footballers with

4

hamstring strain. Although Dynamic stretching is easy to perform and consists of

functional based exercises which use sports specific movements to prepare body for

movement.11-12,16 Muscle energy Technique relatively is a new concept but this technique

requires thorough knowledge to perform. So, there exists a need to find out which is

effective in improving flexibility in footballers with hamstring strain.

Hypothesis :

Null hypothesis: There will be no significant difference between the Effectiveness of Muscle

energy Technique and dynamic stretching on flexibility of footballers with hamstring strain.

6.2 Review of Literature:

Review On Sports Injuries:-

Marcus C. C. W.Elliott, Bertram Zarins, John W. Powell, Charles D. Kenyon (2011)

conducted a study to investigate hamstring strain injuries at the elite level exist in sports such as

Australian Rules football, Rugby, and soccer. Author concluded that hamstring strain is a

considerable cause of disability in football, with the majority of injuries occurring during short

preseason. In particular, the speed position players, such as the wide receivers and defensive

secondary, as well as players on the special teams units, are at elevated risk for injury.17

Julie A. Rechel, Ellen E. Yard, R. Dawn Comstock (2008) conducted a study To compare

practice and competition injury rates and patterns in 5 boys’ sports (football, soccer, basketball,

wrestling, and baseball) and 4 girls’ sports (soccer, volleyball, basketball, and softball) during

the 2005–2006 school years. Author concluded that Rates and patterns of high school sport

injuries differed between practice and competition. Providing athletic trainers with this

information is a crucial step in Developing the targeted, evidence-based interventions required

to effectively reduce injury rates among the millions of high school student-athletes.18

5

Review On Hamstring Strain In Footballers:-

Hui Liu ,William E.Garrett, Claude T. Moorman, Bing Yu (2012) conducted a literature

review is to summarize studies on hamstring strain injury rate, mechanism, and risk factors in

sports .Author concluded that hamstrings strain injury is likely to occur during the late swing

and late stance phase of sprint running. Shortened muscle length, lack of muscle flexibility,

strength imbalance, insufficient warm up, fatigue poor lumbar posture and increased muscle

neural tension have been identified as modifiable risk factors while muscle compositions, age,

race, and previous injuries are non modifiable risk factors.19

Jan Ekstrand, Jeremiah C Healy, Markus Walden, Justin C Lee, Bryan English, Martin

Hagglund (2011) conducted a study to evaluate the use of MRI as a prognostic tool for lay-off

after hamstrings injuries in professional football players and to study the association between

MRI findings and injury circumstances. Author concluded that MRI can be helpful in verifying

and diagnosis of a hamstrings injury and to prognosticate the lay- off time. Radiological

grading is associated with lay-off times after injury. Seventy per cent of hamstrings injuries

seen in professional football are of radiological grade 0 or 1, meaning no signs of fiber

disruption on MRI, but still cause the majority of absence days.20

Anders Hauge Engebretsen, Grethe Myklebust, Ingar Holme, Lars Engebretsen, Roald

Bahr (2010) conducted a study to see if we could identify risk factors for hamstring injuries

among male soccer players. Author concluded that in a multivariate analysis, previous acute

hamstrings injury was found to be a significant risk factor for new hamstring injuries.

Previously injured players have more than twice as high a risk of sustaining a new hamstring

injury.21

Review on Stretching and other treatment modality effect on hamstring flexibility:-

Marc A. Sherry, Thomas M. Best (2004) conducted a study to compare the effectiveness of 2

rehabilitation programs for acute hamstring strain. He concluded that a rehabilitation program

6

consisting of progressive agility and trunk stabilization exercises is more effective than a

program emphasizing isolated hamstring stretching and strengthening in promoting return to

sports and preventing injury recurrence in athletes suffering an acute hamstring strain.22

David O. Draper, Jennifer L. Castro, Brent Feland, Shane Schulthies, Dennis Egge (2004)

conducted a study to compare changes in hamstring flexibility after treatments of pulsed

shortwave diathermy and prolonged stretch, sham diathermy and prolonged stretch, and control.

Author concluded that hamstring flexibility can be greatly improved when shortwave diathermy

is used in conjunction with prolonged stretching.23

Review on Comparison between dynamic and Static stretching in hamstrings strain:-

Kieran O’ Sullivan, Elaine Murray and David Sainsbury (2009) conducted a study to

examine the short term effects of warm- up, static stretching and dynamic stretching on

hamstring flexibility in individuals with previous hamstring injury and uninjured controls.

Author concluded that Warm- up significantly increased hamstrings flexibility. Static stretching

also increased hamstrings flexibility, whereas dynamic stretching did not, in agreement with

previous findings on uninjured controls. The effect of warm-up and static stretching on

flexibility was greater in those with reduced flexibility post- injury.24

Review on Effect of Muscle Energy Technique on Any other muscular strain:-

Captain Eric Wilson, Wilson, E., Payton.O., Donegan-Shoaf (2003) Conducted a study

Effectiveness of Muscle Energy Technique (MET) in improving outcomes for acute low back

pain. Author concluded that MET combined with supervised neuromuscular reeducation and

resistance training exercises may be superior to supervised neuromuscular reeducation and

resistance training exercises alone for decreasing disability and improving function in patients

with acute low back pain with a lumbar flexion restriction.25

Review on Reliability and validity of Visual Analog Scale(VAS):-

7

Veronica Rachelle Avery, University of Toledo (2010) Conducted a study to compare the

numerical rating scale (NRS) and the visual analog scale (VAS) on their assessment of

traumatic and non-traumatic pain in the emergency department, as this has not been well

studied. Author concluded that The NRS and the VAS are both reliable and accurate measures

of pain

Assessment in the emergency department and can accurately measure both traumatic and non

traumatic pain.26

Amelia Williamson, Barbara Hogg art (2004) conducted a study to review aims to explore

the research available relating to three commonly used pain rating scales, the Visual Analogue

Scale, the Verbal Rating Scale and the Numerical Rating Scale. Author concluded that All

three pain-rating scales are valid, reliable and appropriate for use in clinical practice.27

PollyE. Bijur, Wendy Silver, E. John Gallagher (2001) The objective of the Study was to

assess the reliability of the VAS for measurement of acute pain. Author concluded that

Reliability of the VAS for acute pain measurement as assessed by the ICC appears to be high.

Ninety percent of the pain ratings were reproducible within 9 mm. These data suggest that the

VAS is sufficiently reliable to be used to assess acute pain. 28

Review on Reliability and Validity of Active Knee Extension Test (AKET):-

C.M. Norris, M. Matthews (2005) The purpose of this study was to assess inter-tester

reliability of two testers using a novel self-monitored active knee extension (AKE) test in the

clinic Setting. Author concluded that The AKE test when used in conjunction with goniometry,

accurate Surface marking and manual monitoring of the test leg is a reliable measure of

hamstring muscle length.29

Belinda J. Gabbea, Kim L. Bennell, Henry Wajswelner, Caroline F. Fincha (2004) The

purpose of this study was to establish the reliability of eight, musculoskeletal screening tests,

commonly used in the screening protocols of elite-level Australian football clubs. The tests of

interest were Sit and Reach, Active Knee Extension, Passive Straight Leg Raise, slump, active

8

hip internal rotation range of movement (ROM), active hip external rotation ROM, lumbar

spine extension ROM and the Modified Thomas Test. Author concluded that All tests

demonstrated very well to excellent (Interclass correlation coefficient, ICC 0.88–0.97) inter-

rater reliability. Test–retest reliability was also shown to be good for these tests (ICC 0.63–

0.99). His findings suggest that these simple, clinical measures of flexibility and ROM are

reliable and support their use as pre-participation screening tools for sports participants.30

Review on Reliability and Validity Of Goniometric Measurement At the Knee:-

Prem P. Gogia James H. Braatz, Steven J. Rose, and Barbara J. Norton (1987) Conducted

a study to test the intertester reliability of goniometric measurements at the knee and 2) the

validity of the clinical measurements by comparing them to measurements taken from

roentgenograms. Author concluded that The data analysis revealed that the intertester reliability

(r = .98; ICC = .99) and validity (r = .97-.98; ICC = .98-.99) were high. The results of this study

indicate that goniometric measurements of the knee joint are both reliable and valid.31

6.3 Objectives of the study:

1. To find out the effectiveness of Muscle Energy Technique on flexibility of footballers with

Hamstring strain

2. To find out the Effectiveness of Dynamic Stretching on flexibility of footballers with

Hamstring Strain

3. To Compare that which Technique has better effect on Flexibility of Footballers with

Hamstring Strain.

7 Materials and Methods:

7.1 Source of Data

9

Sports Authority of India, Bangalore

ESI Hospital, Rajajinagar, Bangalore.

Padmashree Clinic, Near Nagarbhavi Circle Bangalore.

7.2 Method of collection of data:

Population :- Subjects with Sub Acute Hamstrings strain

Sampling :- Convenient

Sample size :- 30

Type of Study :- Experimental with pre- post test design

Duration of the study:- 6 months

Inclusion Criteria:

Age Group 18-27 years;

Male subjects

Subjects with Sub Acute hamstrings strain(grade II)

Subjects with lack of hamstrings flexibility(Inability to achieve greater than 160o of

knee extension with hip at 90o flexion in popliteal angle)

Exclusion Criteria:

Subjects with lower limb fractures

Hamstrings Contusion

Visible swelling in the region of hamstring muscle

Material used:

Couch

Permanent Skin Marker

Paper

Pen

Goniometer

10

Strap

Measuring tools:

Visual Analogue Scale(VAS)

Active Knee Extension Test (AKET), Popliteal Angle

Methodology

Intervention to be conducted on the participants:

Subjects with Hamstrings strain will be recruited from outpatient Department. Informed

Consent will be taken by the Subjects. The Subjects will be included based on the inclusion and

exclusion criteria .Following an initial assessment the subjects will be divided into two groups:

- Before going for the intervention (Pre measurement will be done). The subjects would be

assessed for the Pain by measuring VAS and for knee Joint ROM and hamstring Muscle length

by measuring (Active Knee Extension Test).

Visual Analog Scale: -

The VAS consists of a 10-cm horizontal line bordered by verbal descriptors of pain intensity.

The descriptor “no pain” is placed to the left of the line, while a phrase describing an upper

pain intensity limit such as “worst pain possible” is placed to the right of the line. The patient is

asked to draw a line perpendicular to the VAS at his/her perceived level of pain intensity. The

examiner will then measure the distance, in millimetres, from the “no pain” anchor that is left

of the line to the patient’s mark to interpret the patient’s pain level.26

Active Knee Extension Test: -

The subject will be in Supine position with hips flexed 90o and knee flexed. A cross bar was

used to maintain the proper position of hip and thigh. The testing was done on the right lower

extremity and subsequently the left lower extremity and the pelvis were strapped down to the 11

table for stabilization and control on accessory movements. Landmarks used to measure hip and

knee range of motion were greater trochanter, lateral condyle of femur and the lateral malleolus

which were marked by a skin permanent marker. The fulcrum of the goniometer was centered

over the lateral condyle of femur with the proximal arm secured along the femur using greater

trochanter as a reference. The distal arm was aligned with the lower leg. The hip and knee of

the

Extremity being tested was placed into 90o flexion. The subject was then asked to extend the

testing lower extremity as far as possible until a stretch sensation will felt. A full circle

goniometer was then used to measure the angle of knee flexion. Three readings were performed

and an average of three was taken as the final reading.14

Group A will receive Muscle Energy Technique

Group B will receive (Conventional)Dynamic Stretching

After 5 days of completion of intervention (Post measurement will be done) again VAS and

Hamstring Muscle length (Active Knee Extension Test) will be assessed and the Data will be

Evaluated.

Group A(Muscle Energy Technique) (n=15):-

This group will receive Muscle energy Technique. The subjects’ knee will be extended to the

position where the subject first reported of any hamstring discomfort and moderate Isometric

contraction (approx 75% of maximal) of the hamstring muscle will be elicited for a period of

five seconds. After a period of three seconds relaxation, the technique would be repeated three

times (for a total of four contractions).The treatment would be given for five consecutive

days.14, 15

Group B (Dynamic stretching) (n=15):-This group will receive (Conventional) Dynamic

stretching. For the dynamic stretch (D), each participant would be instructed to actively swing

the leg to be stretched forward into hip flexion until a stretch was felt in the posterior thigh

12

whilst keeping their knee extended and their ankle plantar flexed. The leg would then allow

swinging back into slight hip extension. This would be repeated for 30 seconds, such that the

dynamic stretch consisted of repeated hip flexion/extension swinging movements. This stretch

would be carried out for 30 seconds and repeated three times. The treatment would be given for

5 consecutive days.24, 32

Outcome measures:

Visual Analogue Scale(VAS)

Active Knee Extension Test (AKET), Popliteal Angle

Statistics:

Data analysis will be performed by SPSS (version 17) for windows. alpha value will be

set as 0.05

Descriptive statistics will be used to find out mean, standard deviation and range for

demographic and outcome variable.

Mann Whitney U test will be used to find out the difference in baseline data for

outcome variable such as VAS

Paired t test will be used to find out significant differences for the Popliteal angle

(AKET) within the groups.

Unpaired t test will be used to find out significant differences for popliteal angle

between the groups.

Wilcoxon Signed Rank Sum test will be used to find out significant differences for VAS

with in groups.

Mann Whitney U test will be used to find out significant differences for VAS between

the groups.

13

Microsoft word, excel will be used to generate graph and tables etc.

7.3 Does the study require any investigation or intervention to be conducted on patients

or other humans or animals? If so, please describe briefly.

Yes , the study will be carried out on human male subjects with the age group 18-27 years

to compare the effectiveness of muscle energy technique versus dynamic stretching on

flexibility of footballers with hamstring strain.

7.4 Has the ethical clearance been obtained from your institution in case of 7.3

As this study involve human subjects, the ethical clearance has been obtained from the

Ethical Committee of Padmashree Institute of Physiotherapy, Nagarbhavi, Bangalore, as per

ethical guidelines research from biomedical research on human subjects, 2000, ICMR, New

Delhi.

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18