Estudio Transversal Sind Banda Iliotibial
-
Upload
tomas-parraguez -
Category
Documents
-
view
227 -
download
0
Transcript of Estudio Transversal Sind Banda Iliotibial
-
8/12/2019 Estudio Transversal Sind Banda Iliotibial
1/23
1
Assessment of Strength, Flexibility, and Running Mechanics in Males with Iliotibial BandSyndrome
Brian Noehren, P, Ph!"
Anne Schmit#, Ph!"
Ross $em%el, BS
"
&arolyn 'estla(e, MS"
'illiam Blac(, M!)
"!i*ision of Physical hera%y, +ni*ersity of entuc(y, -exington, ., +SA)!e%artment of S%orts Medicine, +ni*ersity of entuc(y, -exington, ., +SA
here are no funding sources to disclose/ he study %rotocol was a%%ro*ed by theInstitutional Re*iew Board at the +ni*ersity of entuc(y/
Address corres%ondence to Brian Noehren, )01! 'ethington Building, 200 South-imestone Street, -exington, . 10345/ 67mail8 b/noehren9u(y/edu/
Copyright${year}JournalofOrthopaedic&Spo
rtsPhysicalTherapy.Allrightsreserved.
mailto:[email protected]:[email protected] -
8/12/2019 Estudio Transversal Sind Banda Iliotibial
2/23
2
Study Design8 &ross7sectional laboratory study/
Objectives8 o assess differences in hi% strength, iliotibial band length, and hi% and
(nee mechanics during running between male runners with iliotibial band syndrome and
healthy controls/
Background8 Flexibility, strength, and running mechanics are commonly assessed in
%atients with iliotibial band syndrome :IBS;/ $owe*er, these *ariables ha*e not been
e*aluated concurrently in this %o%ulation/
Methods8 hirty7four males %artici%ated :"< healthy, "< IBS;/ $i% strength was
measured with a hand held dynamometer and iliotibial band flexibility was assessed
using an inclinometer while %erforming the =ber>s test/ inetic and three7dimensional
(inematic data were obtained during running/ inematic *ariables of interest included
frontal and trans*erse %lane hi% and (nee ?oint angles during early stance/ Inde%endent
sam%le t7tests as well as effect si#es were used to assess grou% differences/
Results8 &om%ared to the control grou%, %ersons with IBS had a significantly lower
=ber>s measurement :"/)@;, wea(er hi% external rotators :"/) Nm(g;, greater hi%
internal rotation :4/
-
8/12/2019 Estudio Transversal Sind Banda Iliotibial
3/23
3
%o%ulation/4) !es%ite its high %re*alence, little is (nown about the etiology of this
condition/ !e*elo%ment of IBS is thought to include extrinsic factors :e/g/ training
*olume, shoe wear; as well as intrinsic factors :e/g/ flexibility, strength, running
mechanics, etc/;/
Physical thera%y %rograms ty%ically focus on addressing the intrinsic factors that
contribute to IBS/ 'hile there ha*e been limited re%orts on the role of these intrinsic
factors indi*idually, there has been no com%rehensi*e analysis of these factors within
the same grou%/ Moreo*er, %re*ious studies ha*e consisted of males and females, or
females only/ &onsidering males with IBS as a se%arate grou% may be im%ortant as
%re*ious research has shown that men and women differ in terms of muscular strength
and running mechanics// In addition, establishing an in?ury %rofile in men with IBS is
im%ortant since males com%rise 30 to C" of those suffering from IBS/ 4)
$i% strength and iliotibial band :IB; flexibility are commonly assessed as %art of
the e*aluation of an in?ured runner with IBS/ For exam%le, hi% abductor wea(ness has
been demonstrated in trac( athletes with IBS/")$owe*er, this is in contrast to more
recent research in which no differences in hi% abductor strength in %ersons with IBS
were re%orted/"1 he conflicting results between %re*ious studies could be the result of
different testing %rocedures :isometric *ersus iso(inetic assessment of muscle strength;
and grou% demogra%hics :high le*el athletes *ersus recreational runners;/
'hile there ha*e been a limited number of re%orts on hi% abductor strength in
runners with IBS, there ha*e been no studies e*aluating hi% external rotation strength
in this %o%ulation/ $i% external rotation strength %lays an im%ortant role in %ro*iding
rotary control of the hi% and wea(ness of the external rotators may contribute to greater
Copyright${year}JournalofOrthopaedic&Spo
rtsPhysicalTherapy.Allrightsreserved.
-
8/12/2019 Estudio Transversal Sind Banda Iliotibial
4/23
4
strain on the IB/"-astly, while the =ber>s test is commonly used as an indicator of IB
flexibility, the authors are not aware of any %ublished re%orts e*aluating whether runners
with sym%tomatic IBS exhibit diminished IB length/
Abnormal running (inematics, s%ecifically excessi*e motions of the hi% and (nee
in the frontal and trans*erse %lanes, are often cited as im%ortant contributing factors
with res%ect to the de*elo%ment of IBS/ he attachment sites of the IB ma(e this
structure %articularly *ulnerable to altered secondary %lane running mechanics/
Proximally, the IB is attached to the %el*is through both the tensor fascia latae and
gluteal muscles/ !istally, its insertion includes the lateral femoral e%icondyle and
Derdy>s tubercle/ herefore, greater hi% and (nee adduction, as well as greater hi% and
(nee rotation may increase the tensile strain in the IB/
$amill et al/ ha*e confirmed that runners with sym%toms do ex%erience greater
IB strain rates during the early stance %hase of running/"3 $owe*er, %re*ious
in*estigations e*aluating the (inematic *ariables that may contribute to the de*elo%ment
of IBS ha*e been mixed/ For instance, one study of women with IBS found greater
%ea( hi% adduction and (nee internal rotation whereas another study using a mixed
sam%le of males and female runners with IBS found no differences in hi% or (nee
(inematics/ he lac( of consensus among studies suggests that males with IBS may
ha*e a different (inematic %rofile when com%ared to females/
he %ur%ose of the current study was to assess differences in hi% abduction and
external rotation strength, IB length :=ber>s test;, as well as frontal and trans*erse
%lane (inematics at the hi% and (nee in males with and without IBS/ Based on what is
(nown about the intrinsic factors that may contribute to IBS, it was hy%othesi#ed that
Copyright${year}JournalofOrthopaedic&Spo
rtsPhysicalTherapy.Allrightsreserved.
-
8/12/2019 Estudio Transversal Sind Banda Iliotibial
5/23
5
male runners with IBS would ha*e significantly wea(er hi% abductor and external
rotators, diminished length of the IB, increased hi% and (nee adduction, and increased
hi% internal and (nee external rotation angles com%ared to a %ain7free control grou%/
METHODS
A total of 41 male runners between the ages of "C713 %artici%ated in this study
:"< with IBS and "< %ain7free controls;/ he control and IBS grou%s were similar in
terms of age, distance run %er wee(, mass, and height :able ";/ he number of
sub?ects was chosen to detect a moderate effect si#e :&ohen>s d of 0/3; with reasonable
statistical %ower :E0/C;/
he study was a%%ro*ed by the Institutional Re*iew Board of the +ni*ersity of
entuc(y/ Sub?ects were recruited from local races, %osted flyers, and %hysician offices/
Prior to %artici%ation, all sub?ects %ro*ided written informed consent/ o be considered
for the study, sub?ects in both the IBS and control grou%s had to re%ort running at least
"5 (ilometers %er wee(/ In addition, %ersons with IBS had to re%ort being free from any
other lower extremity in?ury other than IBS for the %ast 5 months/ Similarly, the control
grou% had to be in?ury free for the %ast 5 months/
Indi*iduals with IBS were e*aluated by a %hysical thera%ist to determine if they
Gualified for the study/ Runners in the IBS grou% had to re%ort an insidious onset
lateral (nee %ain while running during the %ast ) months/ Partici%ants were included in
the IBS grou% if they had re%orted %ain of at least 4 out of "0 on the numeric rating
scale during running/ he re%eatability and *alidity of this scale %re*iously has been
re%orted :I&& 0/2470/23;/","s tubercle or the
Copyright${year}JournalofOrthopaedic&Spo
rtsPhysicalTherapy.Allrightsreserved.
-
8/12/2019 Estudio Transversal Sind Banda Iliotibial
6/23
6
lateral femoral e%icondyle, or re%ort %ain during the Noble com%ression test which has
been re%orted to ha*e acce%table inter7rater reliability/5 As %art of the e*aluation,
%ossible ligamentous :*arus stress test; and meniscus in?uries :McMurray test; were
ruled out/"C
6ach sub?ect>s hi% strength was measured with a hand held dynamometer
:-afayette Instruments, -afayette, IN; using %re*iously re%orted %rocedures that ha*e
been shown to be reliable/ o measure hi% abduction strength of the in*ol*ed leg, the
sub?ect was %ositioned in sidelying :non7in*ol*ed side; and %ushed into the
dynamometer using the in*ol*ed leg/ he dynamometer was secured 3 cm %roximal to
the tibiofemoral ?oint line with a stabili#ation stra% around the dynamometer and the
testing table/ $i% external rotation strength was measured in a seated %osition, with the
dynamometer %laced on the inside of the in*ol*ed leg 3 cm su%erior to the an(le ?oint
and held in %lace with a stabili#ation stra%/ "5For both strength tests, the %artici%ants
were instructed to gradually increase how much they %ushed o*er 4 seconds and then
to hold their maximum effort for the next ) seconds/
All indi*iduals %erformed ) %ractice trials followed by 4 testing trials/ he
maximum efforts attained during the 4 testing trials were then a*eraged for each
sub?ect/ he raw force *alues were multi%lied by femur length to %ro*ide a torGue *alue,
normali#ed by mass to account for body si#e, and then multi%lied by "00/ Femur length
was measured as the distance from the greater trochanter to the medial tibiofemoral
?oint line/ A %ost7hoc analysis demonstrated that the normali#ed torGue *alues were not
correlated with mass or height, thus confirming the effecti*eness of the normali#ation
strategy to minimi#e the influence of sub?ect si#e/)
Copyright${year}JournalofOrthopaedic&Spo
rtsPhysicalTherapy.Allrightsreserved.
-
8/12/2019 Estudio Transversal Sind Banda Iliotibial
7/23
7
he length of the IB was assessed using the =ber>s test using %re*iously
established %rocedures/ he indi*idual was %laced in sidelying with the examiner
standing %osteriorly/ he in*estigator>s (nee was %laced on the sub?ect>s bac( for
stabili#ation and to %re*ent the s%ine from rolling bac(wards during the e*aluation/
'hile maintaining the (nee in a slightly flexed %osition :"07"3@;, the sub?ect>s u%%er
thigh was then brought into hi% extension and adduction until the %el*is started to tilt or
when there was no additional hi% adduction mo*ement/ his techniGue has been
%re*iously shown to be reliable :I&& 0/20;/)
-
8/12/2019 Estudio Transversal Sind Banda Iliotibial
8/23
8
tra?ectories were recorded at )00$# with a "3 camera motion analysis system :Motion
Analysis &or%, Santa Rosa, +SA;/ Force data was collected at ")00 $#/
Hisual 4! software :&7motion, Dermantown, M!, +SA; was used to filter the
data, identify the functional hi% ?oint center, and calculate ?oint angles for 3 running
cycles/ Mar(er tra?ectory data was filtered at C $# and force data was filtered at 43 $#
using a 1th order Butterworth low %ass filter with #ero lag/ he cutoff freGuencies were
selected using the results of a residual analysis of the data/45$eel stri(e and toe off for
a running cycle occurred when the *ertical ground reaction force was 40 N/
oint coordinate systems were defined in the Hisual 4! software using %re*iously
%ublished %rocedures/)1he %el*is coordinate system was %laced at the mid%oint of the
line connecting the iliac crests, the J7axis was oriented along the line connecting the
mid%oint of the iliac crests and the mid%oint of the greater trochanters, and the KJ7%lane
was established through a %lane best fit to the iliac crests and greater trochanters *ia
least7sGuares/ A segment fixed coordinate system for the femur was %laced at the
functional hi% ?oint center)Cwith the J7axis defined along a line connecting the hi% ?oint
center and the mid%oint of the femoral e%icondyles and the KJ7%lane established by the
e%icondyles and greater trochanter/ he shan( coordinate system was %ositioned at the
mid%oint of the tibial %lateaus, the J7axis was oriented along a line connecting the origin
and mid%oint of the malleoli, and the KJ7%lane was established by minimi#ing the sum
of sGuares distance between e%icondyles, malleoli, and a %lane/ For all segments, the
.7axis was oriented forward and %er%endicular to the frontal :KJ; %lane and the K7axis
as the cross7%roduct of the J and .7axes/
Copyright${year}JournalofOrthopaedic&Spo
rtsPhysicalTherapy.Allrightsreserved.
-
8/12/2019 Estudio Transversal Sind Banda Iliotibial
9/23
9
oint angles were determined using a &ardan rotation seGuence of flexion,
adduction, and internal rotation, referencing the distal segment to the %roximal segment/
A custom -ab*iew code :National instruments, Austin, exas; was used to extract frontal
and trans*erse %lane hi% and (nee ?oint angles at the time of the initial im%act %ea( for
each trial/ Halues were then a*eraged across the 3 trials for each sub?ect/ oint angles
were obtained during early stance since IBS sym%toms ha*e been re%orted to occur
during this %eriod of time/
Means and standard de*iations of the following *ariables of interest were
calculated for each grou%8 hi% strength, IB length, and frontal and trans*erse %lane hi%
and (nee ?oint angles at the time of the im%act force %ea(/ o assess grou% differences
between these *ariables, inde%endent t7tests were %erformed using SPSS *ersion "C/0
:IBM SPSS, &hicago, Illinois;/ he in?ured limb in the IBS sub?ect was com%ared to the
same limb in the matched control %artici%ant/ !ifferences were considered significant if
%L0/03/
If a *ariable was shown to be statistically significant, clinical rele*ance was
established using the effect si#e and M!&/ 6ffect si#es were calculated in DPower/