Assessment of Hamstring Muscle

8/7/2019 Assessment of Hamstring Muscle

1/6

Assessment of Hamstring MuscleLength in School-aged Children Usingthe Sit-and-Reach Test and theInclinometer Measure ofHip Joint Angle

Background and Purpose. The sit-and-reach test (SRT) is commonlyused to assess flexibility of the spine and length of the hamstringmuscles. The purposes of this study were (1) to describe hamstringmuscle length as reflected by use of the SRT an d the hip joint angle(HJA) in children, (2) to examine the correlation between SRT andHJA measurements, and (3 ) to examine gender differences for bothmeasures. Subjects. The participants were 410 school-aged children(211 girls, 199 boys). Methods. Each child performed the SRT. In thefinal position, the SRT score was obtained an d the HJA was measuredusing an inclinometer placed over the sacrum. Results. A mean SRTvalue of 24 cm and a mean HJA value of 81 degrees were obtained forall subjects. The re was a strong correlation between the SRT an d HJAmeasurements ( ~ . 7 6 ) .There was a difference between boys an d girlsfor both measures. Conclusion and Discussion. The results suggestdifferences in expectations for hamstring muscle length in boys andgirls. Although scores for the SRT and HJA were correlated, we preferto assess hamstring muscle length using HJA scores because thesescores are not influenced by anthropometric factors or spinal mobility.Th e results of this study suggest that HJA measurements guidetreatment more effectively than d o SRT measurements. [Cornbleet SL,Woolsey NB. Assessment of hamstring muscle length in school-agedchildren using the sit-and-reach test and the inclinometer measure ofhip joint angle. Phys Ther. 1996;76:850-855.1

KeyWords: Fitness tests an d m easurements, Flexibility, Ha ms tri ng m u sc b length, Sit-and-reach test.

Suxy L CornbleetNancy B Woolsty

Physical Therapy . Volume 76 . Number 8 . August 1996


2/6

hysical fitness testing is a routine component ofphysical education classes in elementary andsecondary schools throughout the UnitedStates. One area routinely addressed in most

fitness tests is flexibility. The sit-and-reach test (SRT)' ora modified version of the SRT2 is typically used toevaluate flexibility of the low back and hamstring mus-cles. A score is given based on the most distant pointreached by both hands on a standardized box as thechild beiing tested leans forward in a long-sitting position(Fig. 1) . Passing scores are given when children canreach at least 2 cm beyond their t oes1 According to theAmerica.n Alliance for Health, Physical Education, Rec-reation, and Dance (AAHPERD), this flexibility test isimportant because decreased flexibility, particularly inthe hamstring muscles and the back, is thought tocontr ibute to the development of low back pain,' butdata confirming this supposition have not beenprovided.In the literature, the terms "flexibility" and "musclelength" are often used synonymously when referring tothe ability of the hamstring muscles to be lengthened totheir end range.'-'' For the purposes of this article, theterm "muscle length" will be used to refer to the endrange of the hamstring muscles.

ing activity. Jackson and colleagues3.12 investigated therelationships between the SRT and measures of ham-string muscle length (passive straight leg raise) and backflexibility. They reported that the SRT has moderatecriterion-related validity when used to reflect hamstringmuscle length but does not appear to provide a validassessment of back motion. Several authors4-"~~flJ3-16contend that anthropometric factors, such as dispropor-tionate length of the limbs relative to the trunk, mayinfluence the results of the SRT. Children with long legsand a short trunk, for example, may fail the test eventhough they have acceptable hamstring musclelength.8~11,1Wopkins15estimated that scapular abduc-tion during the SRT may account for 3 to 5 cm ofvariation in the final score. A passing score on the SRT,therefore, may be the result of a variety of factors. Thesefactors include various combinations of back motion andhamstring muscle length such as normal or increasedmotion in the back and increased hamstring musclelength (Fig. I ) , decreased or normal back motion corn-bined with increased hamstring muscle length (Fig. 2 ) ,or increased back motion combined with decreasedhamstring muscle length (Fig. 3) ; anthropometric fac-tors such as long arms or short legs relative to the trunk;and scapular abduction, which increases the reachingdistance of the arms.

The SR'T has been the subject of many st u d i e ~ . " ~ , l ~ - ~ ~A We contend that a standard SRT test position can becritique written by KendallH and studies performed by used and, if the final hi pj oi nt angle (HJA) is measuredJackson and colleagues3,12suggest that the SRT score rather than the final position of the hands on the SRTdoes not distinguish between the contributions of the box, this provides a better reflection of hamstring mus-low back and the hamstring muscles during this reach- cle length. Measuring the HJA rather than the distanceSL Cornhleet, PT, is Instruc tor and Academic Coordin ator of Clinical Education, Program in Physical Therapy , Washington UniversitySchool of' Medicine, Box 8502, 4444 Forest Park Ave, St Louis, MO 63108 (US.4) ([email protected]).Address all correspondence to Ms Cornbleet.

NB Woolsep. OT,PT, is Instructor, Program in Physical Therapv. Washington University School of Medicine.This study was approved by the Instit~ltionalReview Board of Washington University.

Th~ surl~cleu~rrrsubmztted on ]U?LP 19, 1993, an d wa s occrpted Febehnca~27 , 1996.

Physical 'Therapy . Volume 7 6 . Number 8 . Augus t 1996 Cornbleet and Wo olsey . 851


3/6

Fi ure 3.Per3ormance of the sit-and-reach test, demonstrating increased backflexibility combined with decreased hamstring muscle length.

Fi ure 1.3Per ormance of the sit-and-reach test, demonstrating normal back flexi-bility and normal hamstring muscle length. must monitor the pelvic position throughout the test.

For example, hip flexor shortness may pull the pelvis inposition could result in an inaccurate assessment of

ithe direction of anterior tilt. Use of this faulty startingshort hamstring muscle length. The use of the long-sitting position allows both hips to move in the samedirection and eliminates the need to stabilize the pelvisor consider the influence of hip flexor shortnes~.~

Fi ure 2.Per3ormance of the sit-and-reach test, demonstrating normal back flexi-bility combined with increased hamstring muscle length.

of the fingertips to the toes eliminates some anthropo-metric factors or scapular abduction from influencingthe score. We realize that this method excludes a mea-sure of back motion. We contend, however, that if backmotion is considered important for the assessment offitness, it could be measured with a more appropriatetest.I 7-19For the purpose of our study, hamstring muscle lengthwas reflected by the angle of inclination of the sacrumand pelvis relative to thc horizontal at the point ofmaximal forward reach in the SRT. This represents anindirect measure of the hip joint angle (HJA). Althoughseveral other methods of assessing hamstring musclelength have been re p0 rt ed ,~ ~~ .~ . ' ~- -2 ~we contend that thismethod is preferable. When compared with the standingtoe-touch test, we believe tha t the long-sitting positioneliminates posterior sway and allows for better control ofthe knee joint position and for bet ter control of thepelvis in terms of rotation or lateral Th e supinepassive straight-leg-raising test and the supine kneeextension test with the hip in 90 degrees of flexion areperformed on one lower extremity while the other lowerextremity is resting in hip and knee extension. Toachieve accurate results, we believe that the examiner

Another aspect of the SRT that needs to be considered isthe criteria for passing t he test. Currently, boys and girlsare required to meet the same standard.' Our clinicalexperience, however, suggests that boys and girls maynormally have differences in hamstring muscle length.The purposes of our study were (1 ) to characterizehamstring muscle length by use of the HJA and SRTscores in a sample of school-aged children and (2 ) to testthree hypotheses related to these measures. Thesehypotheses were:1. The re would be a correlat ion between SRT scores and

HJA scores.2. There would be no difference between SRT scores for

boys and girls.3. There would be no difference be~wee nHJA scores for

boys and girls.MethodSubjectsA total of 410 children (2 1 1 girls and 199 boys) withoutknown impairment of the musculoskeletal system affect-ing the spine o r the lower extremities participated in thestudy. The subjects were students in kindergartenthrough sixth grade from public and private elementaryschools in St Louis County, Illinois. Th e subjects' agesranged from 5 to 12 years, with a mean age of 7 years 10months. Informed consent was obtained from the par-ents of all subjects.

852 . Cornbleet and Woolsey Physical Therapy. Volume 76 . Number 8 . August 1996


4/6

Figure 4.Superior view of the ruler on the sitand-reach box.

!

InstrumentationA standard sit-and-reach box* was used to position thesubjects for the test, and the sliding ruler that is centeredon the top of the box was used to obtain the SRT scores.The markings on the ruler were positioned so that the23-crn mark represented the point at which the subjects'fingertips were in line with their toes (Fig. 4) . In this way,the SRT score was always a positive number, even for thechildren who were unable to reach their toes. Theminimal acceptable score to pass, as determined byAAHPERD," is 25 cm, or 2 cm beyond the toes, for allages and both genders and without consideration ofanthropometric variables.

80;.-1-

Figure 5.Normal hamstring rnuscle length but failing performance of the sit-and-reach test due to anthropometric factors (long legs relative to trunk andarms).

An inclinometert (a circular, fluid-filled goniometer)was usetl to measure the HJA. The inclinometer was setso that 0 degrees represented the horizontal, or 0degrees of hip joint flexion. The inclinometer wasplaced vertically on the sacrum so that the center of theinclinometer was aligned at the level of the posteriorsuperiol- iliac spines.Interrater reliability, using an inclinometer to measurethe HJA, was examined for the first 20 subjects betweentester 1 and tester 2. An intraclass correlation coefficient(2 ,l ) of .98 indicated to us an acceptable level ofinterrater reliability for the HJA scores.A passing HJA score was determined by the examiners tobe 80 degrees or more of hip joint flexion. This valuecorresponds to what Kendalls considers normal if ham-string rnuscle length is normal, as determined by thefinal po'sition of the hip joint during straight leg raising

'Amer-icar~.Uliance for Hralt t~ ,Physical Education. Recreation, and Da nce, 1900Association Dr, Reston, VA 22091.

Biokine~icsInc. 1 710 W esuninstel- Way, Arulapolis, MD 21401.

or the angle between the sacrum and the table duringforward bending in the long-sitting position. Otherinvestigatorsg~" also have used this value as a guidelinefor normal hamstring muscle length.ProcedureEach child was seated on the floor with knees fullyextended and ankles in neutral dorsiflexion against thebox (Fig. 1).Th e child was instructed to place one handon top of the other and slowly reach forward as far aspossible while keeping the knees extended. The handswere kept aligned evenly as the subject reached forwardalong the surface of the box. Each child practiced themovement twice, and, on the third repetition, the SRTscore (in centimeters) was recorded as the final positionof the fingertips on the ruler. During the same trial, theinclinometer was placed over the sacrum and the HJAwas measured and recorded.Data AnalysisThe mean for all subjects and the means for boys andgirls were calculated for the HJA and the SRT.A t test forindependent samples was used to examine differencesbetween boys and girls for the HJA and the SRT. ThePearson product-moment correlation coefficient wasused to examine the relationship between the SRT andthe HJA. Raw scores were examined to determine the-number of cases in which the scores on the two testsappeared to be contradictory. For example, some chil-dren were able to reach at least 25 cm on the SRT boxbut had decreased hamstring muscle length as definedby the HJA (Fig. 3), whereas othe r children could notreach the 25-cm mark but ha d normal hamstring musclelength (Fig. 5).ResultsThe Table presents the means and standard deviationsfor the SRT and HJA. There was a difference betweenthe scores for boys and girls on the HJA test (t=7.81,df=408, P


5/6


6/6

References1 Physical Best. Reston, Va: American Alliance for Health, PhysicalEducat ion, Recreation , and Dance. 1988:14, 28-29.2 The Prudential Fitnessgram. Dallas, Tex: Cooper Institute for AerobicsResearch. 1992:28-30.3 Jackson AW, Baker AA. Th e relationship of the sit and reach test tocriterion measures of hamstring and back flexibility in young females.Rer Q Ex m Sport . 1986;57:183-186.4 Wells KF, Dillon EK. The sit and reach: a test of back and legflexibility. I& Q. 1952;23:115-118.5 Hoeger WWK, Hopkins DR, Button S, Palmer TA. Comparing the sitand reach with the modified sit and reach in measuring flexibility inadolescents,. Ped iatric Exercise Science. 1990;2:156-162.6 Hopkins DR, Hoeger WWK. A comparison of the sit-and-reach testand the modified sit-and-reach test in the measurement of flexibilityfor males. Journal of Applied Sports Science Research. 1992;6(1) :7-10.7 Bohann on RW. Cinematographic analysis of the passive straight-leg-raising test for hamstring muscle length. Phys Ther 1982;62:1269-1274.8 Kendall FP, McCrealy EK. Muscles: Testing and Function. 3rd ed.Baltimore, Md: Williams & Wilkins; 1983:38-48.9 Gajdosik RL, Giuliani CA, Bohannon RW. Passive compliance andlength of the hamstring muscles of healthy men and women. ClinBiomech. 1990;5:23-29.10 Shephard RJ, Berridge M, Montelpare W. On the generality of the"sit and reach" test: an analysis of flexibility data for an agingpopulation. Res QExerc Sport. 1990;61:326-330.11 Kendall FP. A criticism of current tests and exercises for physicalfitness. Phys Ther. 1965;45:187-197.12Jackson A, Langford NJ. The criterion-related validity of the sit-and-reach test: replication and extension of previous findings. Res Q ExercSpurt. 1989;60:384-387.13 Kendall HO, Kendall FP. Normal flexibility according to agegroups. ]Bone Joint Surg [Am]. 1948;30:690-694.14 Broer MR, Galles NRG. Importance of relationship between variousbody measurements in performance of the toe-touch test. Res Q.1958;29:253-263.

15 Hopkins DR. The relationship between selected anthropometricmeasures and sit-and-reach performance. Presented at the AmericanAlliance for Health, Physical Education, Recreation, and DanceNational Measurement Symposium; 1981; Houston , Tex.16 Wilmore JH, Costill DL. Athletic Tra ining for Sport and Activity.Dubuque, Iowa: William C Brown; 1988.17 Boline PD, Keating JC, Haas M, Anderson AV. Interexaminerreliability a nd discriminant validity of inclinometric meas urement oflumbar rotation in chronic low-back pain patients and subjects withoutlow-back pain . Spine. 1992;17:335-338.18 Haley MH, Tada WL , Carmichael EM. Spinal mobility in youngchildren. Phys Ther. 1986;66:1697-1703.19 Mayer TG, Tenc er AF, Kristoferson S, Mooney V. Use of noninvasivetechniques for quantification of spinal range-of-motion in normalsubjects and chronic low-back dysfunction patients. Spine. 1984;9:588-595.20 FiskJW.The passive hamstring stretch test: clinical evaluation. N ZMedJ. 1979;88:209-211.21 KippersV, Parker AW. Toe-touch test: a measure of its validity. PhysTher. 1987;67:1680-1684.22 Gajdosik RL, Lusin G. Hamst ring muscle tightness: reliability of anactive-kneeextension test. Phys Ther. 1983;63:1085-1088.23 Gajdosik RL.,Hatcher CK, Whitsell S. Influence of short hamstringmuscles on the pelvis and lumbar spine in standing and during thetoe-touch test. Clin Biomech. 1992;7:38-42.24 Sallis JF, McKenzie TL, Alcaraz JE. Habitua l physical activity andhealth-related physical fitness in fourth-grade children. American Jour-nal ofDiseases of Children. 1993;147:890-896.25 Burton PK, Tillotson KM, Tro up JDG. Variation in lu mbar sagittalnobility with low-back trouble. Spine. 1989;14:584-590.26 Salaimen J, Maki P, Oksanen A, Pentti J. Spinal mobility an d trunkmuscle stre ngth in 15-year-old schoolchildren with and without low-back pain. Spine. 1992;17:405-410.27 Stokes IAF, Wilder DG, Frymoyer JW, Pope MH. Assessment ofpatients with low back pain by biplanar radiographic measurement ofintervertebral motion. Spine. 1981;6:233-240.

Physical Therapy . Volume 76 . Number 8 . August 1996 Cornbleet and Woolsey . 855

Documents

Assessment of Hamstring Muscle