the natural history of hip deformity in myelomeningocele
TRANSCRIPT
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7/25/2019 The Natural History of Hip Deformity in Myelomeningocele
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76 0 T H E JO U R N A L O F B O N E A N D JO IN T SU R G E R Y
THE NATURAL H ISTORY OF H IP DEFORM ITY IN
MYELOMEN INGOCELE
N IG E L S . B R O U G H T O N , M A L C O L M B . M E N E L A U S , W IL L IA M G . C O L E ,
D A V ID B . S H U R T L E FF
F rom th e R oya l C h ild ren s H osp ita l, M e lbo urne , A ustra lia an d the C h ild ren s H osp ita l an d M ed ica l
C en ter , S ea ttle , U SA
W estu d ied 1 06 1 child ren w ith
m y e lom en in goce le, rev iew ing
3 84 pe lv ic rad iog raph s from 80 2 pat i ents . H ip d islocat ion
had occurred by th e ag e o f
iu
years in 28 o f ch ild ren w ith
a tho ra cic n eu ro segm en ta l leve l, 3 0 o f those w ith an Lu
2
lev el, 36 o f L 3 , 2 2 of LA , 7 of L 5 an d on ly 1 of
th ose w ith sac ral levels . H ip d isloca tion w as not in ev ita b le
even w hen th ere w as m axim a l m u sc le im ba lance ab ou t the
h ip . T he averag e h ip flex io n con tra c tu re in ch ild ren aged 9
to
uu
year s w a s s ig n ifican tly g rea ter in th ose w ith tho ra cic
(22 {176 })n d L 1 /2 (3 3 {17 6})ev els than in tho se w ith LA (9 {1 76} ),5
(5 {176} )
r sacra l (4 {1 76 })evels .
O ur find ing s in d ica te tha t m usc le im ba lance is n o t a
s ign if ican t fac tor in th e prod uc tion of fle xio n d efo rm ity o r
d islo ca tion o f the hip;
both
a re co m m o nly seen in th e
abs ence of im ba lance . T he restora tion of m usc le ba lance
s hould no long er b e con s id ered to be th e pr in c ipa l a im of
th e m anagem en t o f th e h ip in ch i ld ren
with m yelom eningo-
cele .
J B on e Join t Surg [B r]
19 93 ; 75 -B
:760- 3 .
R ece ived 20 D ecem ber 1991
;
Accepteda fte r rev isio ns 22 Ap ril 1993
C h ild ren w ith m y elo m ening ocele com m only d eve lop
con tractu res o f th e h ip
;
som e m ay suffe r d is lo ca tio n , an d
th e n atu ra l h is to ry of th ese de form itie s is im p ortan t in
m anagem ent. S h arra rd (19 64 ) rep orted the d efo rm ities
p resen t a t th e age of o ne yea r in 1 83 ch ild ren w ith
m ye lo m eningo cele . H e foun d n o h ip d is loca tion s or
flex io n d efo rm ities in lim b s w ith no in ne rva tio n be lo w
T 12 and the re fo re n o ac tive m usc le s arou nd the h ip . In
h ip s w ith inn erva tion to L i and L 2 , h ip addu ctio n an d
N . S . B rou gh ton , F R C S, F R C S E d , FR A C S, C onsulta nt O rth opa ed ic
Surgeon
M . B .
M e ne lau s, M D , F R C S, F R A C S , Se nio r O rth op aed ic S urgeo n
W . 0.
C ole, M Sc, P hD , F R A C S , P rofessor o f O rtho pa edic S urg ery ,
Me l b o u r n e
D epar tm ent
o f O rth opa edics, R oya l C hildre ns H o spital, F le m ington
R oa d, Parkville , V icto ria 3 05 2, A ustralia .
D . B .
S hu rtle ff, M D, Profe sso r of Pa ediatrics
D ivisio n o f E m b ryo log y, T e rato lo gy an d C on ge nita l D e fec ts, U niver-
sity of W a shington S cho ol o f M e dic ine, C hild ren s H ospital an d
M ed ica l C enter, Se attle , W a shington 98 105 -03 71 , U SA .
C orrespon den ce sho uld be sen t to D r N . S . B rou ghton.
19 93 B ritish E dito ria l S ociety ofB on e an d Join t S urg ery
030 1-6 20 X /9 3/S 6S 3 $2 .00
flex ion co ntrac tu re s had deve lop ed , and m ost w ere
sub lu xed . H e co nsid ered th a t the se h ips w ou ld inev itab ly
d islo ca te by the age of five yea rs . M ost o f th e h ip s
inne rva ted to L 3 and L 4 h ad d isloca ted b y on e yea r and
he sta ted tha t the o th ers w o u ld do so w ith in ano th er year .
O f 27
h ips in ne rv ated to L5 , sev en w ere d isloca ted an d
12 w ere su b lu xed ; S ha rrard sta ted tha t the sub lux ed h ips
w o uld inev itab ly d isloca te b y the ag e of sev en y ea rs . H is
v iew w as tha t m uscle im ba lance cau sed co n trac tu re s an d
d islo ca tion s, and he su ggested th at th e re sto ratio n o f
m u scle ba lance arou nd th e h ip w ou ld p rev en t the se an d
im prove w a lk in g ab ility .
W e repor t a m uch larger study of th e d eve lopm en t
of h ip de fo rm ity in ch ild ren w ith m ye lom en in goce le ,
u sin g da ta co lle cted p rospec tive ly and b efo re any
op e ra tion , o ve r 17 yea rs in tw o cen tre s . A prev iou s pape r
from the sam e cen tre s has d iscu ssed th e p ro g ress ion o f
h ip f lex ion co n trac tu re (S hurtle ffe t a l 198 6) .
P A T IE N T S A N D M E T H O D S
O fthe to ta l s tud y grou p of 10 61 ch ild ren w ith m y elom en -
ing ocele, d etails o f
76 4
h av e been co llec ted by D B S from
S eattle , W A sin ce 19 71 , and 2 97 from M elbo urn e,
A u stra lia b y M B M sin ce 1 976 .
A t th e first a ttendance, a t any age , a sp ecia lly tra in ed
phy sio the rap ist reco rded th e range of m ovem en t in each
d irectio n a t each low er lim b jo in t, m usc le stren g th on th e
stan da rd in te rn atio na l scale fo r a ll m usc le s o f the low er
lim b s (D an ie ls and W orth ing ham 198 6), am b u la to ry
ab ility an d an y orth opaed ic ope ra tio ns o n the low er
lim b s. In terob se rv er d iffe rences in th e se m easu rem en ts
have been fou nd to be sm a ll (B a rtle tt e t a l 1 985 ).
T he neuro seg m ental leve l in each case w as assessed
by a m od if ic atio n o f S ha rra rd s c las sific a tion (T ab le I) ,
an d th ree ch ild ren w ith g ros s asym m etry o f leve l w ere
ex clu ded . A n ov era ll neu rosegm en ta l leve l fo r each ch ild
w as de te rm ined from a ll av ailab le a ssessm en ts in th e
kno w ledge th at m uscle s tren g th beco m es m o re con sis ten t
af te r th e age o ff ive y ea rs (M cD o na ld , J affe and S h urtle ff
198 6) . T h e d istrib u tion o f leve ls is sho w n in T ab le II .
A tota l o f 318 4 rad iog raphs o f 8 02 p atien ts w ere
a sse ssed and h ip s w ere ca teg o rised as d islo ca ted w hen
th ere w as n o area of con gru ity be tw een the fem ora l and
acetabu lar su rface s. A ll o bse rv atio ns re latin g to the
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THORAC IC LEVEL
10 0
90
80
70
60
50
40
10 0
90
80
70
60
50
40
L 1/2
100
90
80
70
60
50
40
L3
I
I I I I I I I
0 2 4 6 8 10121416182022
A ge in yea rs
SACRAL LEVEL
100
90
80
70
60
50
40
, )n .
50
40
Cof l .
I I I I I I I I I I I U I I I I I I I I I I I I I I I I I I U I I
0 2 4 6 8 10121416182022 0 2 4 6 8 10121416182022 0 2 4 6 8 10121416182022
A ge in years Age in yea rs A ge in yea rs
T H E N A T U R A L H IS T O R Y O F H IP D E FO R M IT Y IN M Y E L O M E N IN G O C E L E
76
V O L. 75 -B , N o. 5 , S E PT E M BE R 1993
n a tu ra l h is to ry o f de fo rm ities w ere m ad e be fo re any h ip
operat ion .
D ata w ere sto red usin g the P a tien t D ata M anage -
m ent S ystem (IB M P C com pa tib le so ftw a re standa rd ised
b y th e In te rna tion a l M ye lody sp la sia S tud y G roup ) and
R -BA SE . Sta tist ica l ana ly sis w as by SP SS -X on a
m ain fram e co m pu ter o f th e U nive rsity o f M e lbou rn e
an d S P S S /P C . M eth ods in clu ded one -w ay an aly sis o f
va riance and m ultip le co m parisons by the T u key-H S D
test, d iffe ren ce o f m ean s by S tud en ts t- te st an d su rv iva l
cu rves and com pariso ns usin g L ee -D esu S ta tis tic .
RESULTS
H ip d is loca tion . T he propor tio n o f h ip s rem ain ing
un d isloca ted w as re la ted to age fo r each neurosegm en tal
leve l and is repo rted in the fo rm of su rv iva l cu rves to
ind ica te the ages at w h ich d islo ca tion o ccu rred . P e lv ic
rad io g rap hs w ere ava ilab le fo r m ost ch ild ren a t abo u t
tw o-y early in te rva ls , so m e as pa rt o f u ro lo g ica l in vesti-
ga tion s. B ecause o f the in te rva ls , the d iagno sis o f som e
d islo ca tion s w as d e lay ed and the cu rv es m ay be d isp laced
to the rig h t.
W hen ope ra tion s had been p erfo rm ed it w as
im po ssib le to de te rm in e w h eth er the h ip s w o u ld have
d islo ca ted w ithou t su rge ry . A ccord in g ly , w e g iv e tw o
curves fo r each neuroseg m en ta l lev el : on e is fo r the
ob served d is locatio n rate , th e o the r inc ludes d is locatio ns
an d h ips on w h ich an o pe ra tion has been pe rfo rm ed (F ig .
1 ). T he n atura l d is loca tion rate w itho u t the in flu en ce of
an y op era tio ns m u st lie be tw een these cu rv es. T hey sh ow
clea rly tha t pa tien ts w ith an L 3 neurosegm en ta l lev el
ten d to d isloca te ea r ly , w ith no m o re d isloca tio ns a fte r
the age o f th ree yea rs , w he rea s pa tien ts w ith tho rac ic
an d L l/2 lev els co n tinu ed to su ffe r h ip d isloca tions even
afte r the age of ten y ears (T ab le III). T he g raphs a lso
sho w th a t 42 % of the h ips w ith L 3 neurosegm en tal leve l,
67 %
w ith L 4 lev e l an d 80% w ith L 5 leve l neve r d isloca ted
or h ad op era tio ns pe rform ed on th em .
S ta tis tica l ana lysis o f the su rv iva l cu rves fo r d islo -
catio n o r op era tion , usin g L ee -D esu S tatis tic o n S P S S -X ,
sho w ed n o sig n if ican t d iffe ren ce be tw een th e cu rves fo r
tho rac ic, L i/2 and L 3 leve ls , bu t all th ree g rou ps h ad
sign ific an tly h ig he r d isloca tion rate s th an L 4 , L 5 and
sac ra l leve ls .
H ip
f lex ion con trac tu re . W e ca lcu lated the ave rag e h ip
flex io n con tractu re in un op era ted p a tien ts fo r each
neuroseg m en ta l leve l an d fo r tho se w ith n o lo ss fo r each
o f the ag e ca tego rie s 0 to 3 m o n ths , 9 to 15 m o n ths , an d 9
to 1 1 y ea rs . T he re su lts are show n in T ab le s IV , V an d
V I, w h ich in c lud e on ly on e read ing p er ch ild w ith in each
age catego ry , alth oug h o ne ch ild m ay app ea r in o ne , tw o
o r a ll th ree age ca tego ries . T h is m eans tha t th e sing le
o bse rv a tio ns a re no t independ en t an d cann o t b e co m -
p ared in term s of neu rosegm en tal lev els b etw een ag e
ca teg o ries , bu t on ly w ith in each age categ o ry . W e used
o ne -w ay ana lysis o f va riance an d T ukey -H S D m ultip le
com pariso n m eth ods .
H ip flex ion con trac tu re is com m o n in n orm a l
neon ate s (H offe r 19 80); w e foun d it in all n eu ro seg m en ta l
U I I I I U I I I I I
I 2 4
6 8 10121416182022
Age In yea rs
L4
10 0
)
2 4 6 8 10121416182022
Age In yea rs
L5
100
90
80
70
60
50
40
)A.
D is lo ca tion observed D isloca tion
o r o p er at io n
Fig . 1
H ip dis loc atio n rates in ch ildren w ith m ye lom en ing oc ele. R esu lts are for d if fere nt ne uro seg m e nta l lev els an d ex pre sse d a s percen tag es of hips n ot
d is loc ated at the var iou s ag es (see te xt).
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L e v e l
Thoracic
L
L2
L3
L4
T able II. D istr ibu tion o f n eurose g-
m ental leve ls in 106 1 ch ild ren w ith
m yelom eningo ce le stu die d a t tw o
centres
L e v e l
Thoracic
Ll
L2
Seatt le
(n=764)
13 9
30
25
Me l b o u r n e
( n= 297)
71
14
L 3 60 2 7
L 4 1 86 8 6
L S 8 2 2 7
S 9 0 4 9
S2 76 12
A sym m etrical 2 1
N olo ss 7 4 3
T a ble I II. R e sults o fsu rvival a nalysis ofh ip dislo cation
in children w ith m yelo m en ing oc ele
T a b l e
IV .
A ve rag e hip flexion co ntrac-
ture in childre n w ith m y elo m e nin go cele
from b irth to a ge thre e m on ths
Percentage
L ev el N u m b er
ercen t ge
dis located
d islo ca ted or
o perate d on
A t 3 6 to 59 m on ths
T horacic 75 17 50
L /2
22 12 55
L 3 37
36 48
L 4 155
6 3
L S 4 4 7 17
S ac ral 77
1 2
A t 1 08 to 1 31 m o nth s
T h ora cic 28
28 59
L /2 13 30 75
L 3 1 9
36 50
L4
55 22 33
L S 1 7 7 20
S ac ral 30
1 2
L e v e l
Thoracic
Ll/2
L3
L4
L5
Sacral
N o loss
Nu m b e r
o f h ip s
12 8
54
39
20 5
82
11 8
28
T ab le V . A v erag e hip fle xio n co ntractu re
in c hildre n w ith m y elo m e nin goc ele from
9 to 15 m onths o f ag e
T ab le V I.
A ve rage hip f lexion co ntra c-
ture in children w ith m yelom enin go cele
fro m 9 to 11 yea rs of age
L e v e l
Thoracic
L1/2
L3
L4
LS
Sacral
N o loss
Nu m b e r
o f h ip s
87
36
31
18 4
82
11 8
38
L e v e l
Thoracic
L /2
L3
L4
LS
Sacral
N o loss
Nu m b e r
of h ips
6
l2
13
49
39
10 0
24
76 2
N . S . B R O U G H T O N , M . B . M E N E L A U S, W . G . C O L E , D . B . SH U R T L E F F
T H E JO U R N A L O F B O N E A N D JO IN T S U R G E R Y
T ab le I. T h e a sse ssm en t of n eurose gm ental lev el in ch ild ren w ith
m ye lom en ing oce le m od ifie d fro m S harrard (19 64)
N o active m ov em en t at th e hip
Ilio pso as g rad e 2 or better
Ilio pso as , sarto riu s an d ad duc tors a ll g rade 3 o r be tte r
Q ua dric eps gra de 3 or better, a lso m ee t cri teria fo r L 2
M e dia l ham string s o r tib ia lis anterio r g rad e 3 o r be tte r
;
also
m eet cri teria for L 3
L 5 L a teral h am str ing s g rad e 3 o r be tter ; also m eet c rite ria fo r L 4
plus o ne of the fo llow ing th ree : g lu te us m edius grade 2 o r
be tter , perone us tertius gra de 4 or b ette r, t ib ialis po ster ior
g rad e 3 o r b ette r
5 T w o of the fo llow ing thre e : ga stro cne m ius/so le us grade 2 or
be tter , g lu teu s m edius grade 3 or b etter, g lu teu s m ax im us
grade 2 o r b ette r
;
also m eet cri teria for L S
S2 G a strocn em ius /so leus g rad e 3 o r be tte r and glu teus m ed ius a nd
glu teu s m axim u s g rad e 4 o r be tter , also m eet c rite ria fo r S i
N o loss A ll le g m uscle sha ve no rm a l s tren gth
H ip fl ex io n
c on trac ture (deg ree s)
M e a n
SD
2 1.3 1 2 0.5 7
2 6.4 3 17.14
3 2.2 1 16.49
2 8.5 1 15 .66
2 7.5 11.53
1 8.2 5 13.17
6.0 16.6
H ip
f lex ion
c ontrac ture (deg ree s)
Me a n SD
1 1.4 4 16 .63
9.6 4 14.63
7 .74 13.65
4 .92 9 .88
5 .98 12 .30
1.1 5 7.3 6
0 0 6 97
H ip Il ex io n
con tra ctu re (d egrees )
Me a n SD
22.16 2 1.4 4
3 2.9 1 10.54
11 23 15 59
9.48 17.47
5.3 8 10.22
3.5 3 8.7 6
-1 .25 7.1 0
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T H E N A T U R A L H IST O R Y O F H IP D E FO R M IT Y IN M Y E L O M E N IN G O C E L E
76 3
V O L . 75 -B , N o. 5 , SE PT E M B E R 19 93
lev els o f ch ild ren w ith m y elo m en in goce le (T ab le IV ).
T h e av erage h ip flex ion con tractu res be tw een 9 an d 1 5
m o nths are sh ow n in T ab le V . T he th o rac ic g rou p has a
sign ific an tly h ig he r ave rag e than the L 4 ,
L 5, sac ral and
no lo ss g ro ups . T h e L l/2 g roup has a sig n if ican tly h igh e r
av erage th an th e sac ra l and n o loss g ro ups , bu t the re a re
no sign if ic an t d iffe rences b e tw een o th e r g rou ps.
B etw een 9 and 1 1 y ea rs th e av erage h ip flex ion
con tractu re s sh ow a s ig n if ican tly h ighe r ave rage fo r th e
tho rac ic g rou p than fo r the L 4 , L 5 an d sac ra l g rou ps
(T ab le V I). T h e L l/2 g rou p had a sign ifican tly h ig he r
ave rage than the L 3 , L 4 ,
L 5 , sacra l and no loss gro up s.
T h e L 4 gro up av e rag e w as sig n ifican tly h ighe r th an the
no loss g roup , bu t the re w ere no sign ific an t d iffe ren ces
be tw een th e o the r g roup s.
W e m ade a sp ec if ic ana lysis to d e term ine w heth er
the low er av erage h ip f lex ion con trac tu re in each of the
L 4, L 5 and sacra l group s at 9 to 15 m onth s w as due to
ex clu sion because o f p rev iou s su rge ry , and fo und tha t
th is w as no t the case . T he ave rag e h ip f lex ion co n trac tu re
in p atien ts w ho h ad su rge ry a t le ss than 1 5 m onth s w as
15 {176}or tho se w ith L 3 or m ore d istal neuro seg m enta l lev els
(n
=
20 ) and 2 9#{ 176 }or th ose w ith tho rac ic o r L l/2
n eu ro segm en ta l lev e ls (n
=
12) .
D I S C U S S I O N
T he d a ta w h ich w e h av e u sed have b een co llec ted by
ca refu lly -train ed p erso nne l to m in im ise in terob serve r
an d in traobserve r erro r (B artle tt e t a l 19 85
; B roug hton e t
al 1 98 9). O u r re su lts fro m th e stu dy o f 10 61 child ren o ve r
a pe rio d o f 2 2 yea rs in S ea ttle and 17 yea rs in M e lbo urn e
d iffe r from th ose o f S h arra rd (19 64) . H e stud ied 18 3
ch ild ren an d h is obse rva tions led h im to pos tu la te th at
m usc le im ba lance w as the cau se o f d islo ca tio n and
de fo rm ity o f the h ip .
F or le sion s a t th e th orac ic lev el w e found unexp ec -
ted ly h ig h ra te s o f d islo ca tion in the absence o f m u sc le
im ba lan ce. W e also foun d th at flex io n con trac tu re o f the
h ip w as co m m o n in pa tien ts w ith h igh -leve l le sion s : by
the age of 1 1 yea rs , in tho rac ic leve l p atien ts , the av erage
h ip flex ion con tractu re w as 2 2#{ 17 6}n
=
61 ). C hild ren w ith
ad duc to r an d flexo r pow er a sso cia ted w ith L i o r L 2 lev e ls
at the sam e age d id no t hav e a sig n ifican tly d ifferen t
av erage flex ion de fo rm ity than d id the th o rac ic leve l
gro up w ith n o m u sc le po w er at the h ip . B y th e ag e of 11
years , o n ly 30 % of the L l/2 g rou p of ch ild ren had
d islo cated h ips and
45
h ad been op era ted upo n , u sua lly
fo r p rog re ssive f lex ion d efo rm ity . T h is m eans tha t
25
had ne ith er d is lo cated n or b een o pe ra ted u pon .
In th e ch ild ren w ith an L 3 lev el, on ly 36 % o f h ips
had d isloca ted by the age of f ive yea rs an d th is num ber
d id no t inc rea se in late r life . In a ll, 42% of th e h ips o f
ch ild ren w ith th is lev el ne ithe r d islo ca ted n or had
operat ions.
In ch ild ren w ith L 4 neu roseg m en tal leve l le s ion s ,
w hich sh ou ld g iv e th e m ax im um m u sc le im b alance across
the h ip , 67 % of the h ip s ne ith er d is lo ca ted no r requ ired
ope ratio n . T h e av erage h ip flex io n con tractu re in th is
g roup at th e age of 1 1 y ea rs w as sign ific an tly le ss than
tha t in ch ild ren w ith fla il h ip s. In th e gro up w ith an L 5
neuro seg m enta l lev el on ly 7 % had dislocated b y th e age
of fiv e years , an d at the age o f 1 1 y ea rs , 80 % had n e ithe r
d islo ca ted n or had op era tio ns.
W e there fo re a gree w ith B eek er and Sch eers (198 6)
tha t h ip de fo rm ity and d isloca tion a re no t a s com m on as
w as firs t assum ed and th at the deve lop m en t o f th ese
abn orm alitie s can no t be p red icted o n th e b asis o f th e
leve l o f th e le sion . T h e concep t th a t m uscle im b alance is
respon sib le has been accep ted an d is repeated in m o st
tex t b oo ks (V and er B rin k 1 98 0). It also p rov ides th e
ra tiona le fo r m an ag em en t w h ich in clu des the co rrectio n
o f m usc le im ba lan ce . O ur re su lts ind ica te th a t the se
co ncep ts a re no long er va lid .
T he h igh in cidence of h ip d islocation and flex io n
con trac tu re in h ig h-lev el les io ns lead s us to h ypo th esise
th at com p lete ly pa ra ly sed h ips d isloca te sim p ly b ecause
th ey are no t k ep t in p lace by no rm a l m usc le ton e. In
add ition , bo th p ro lon ged sittin g and sp in al de fo rm ity
m ay en co urag e the deve lop m en t o f flex io n co n trac tu re
an d d isloca tion . T h is m eans th a t h ip de fo rm ity cann o t
b e p red ic ted fro m m u sc le im ba lance abo u t th e h ip , and
tha t p ro phy lactic surg ery to co rrec t m u sc le im b a lan ce is
illo g ica l. C h ild ren w ith m ye lom en in go ce le requ ire care -
fu l obse rva tion to de tect the d eve lopm en t o f d e fo rm ity
o r d is location ; it is n o t p ossib le to pred ic t th e sev erity o f
any d efo rm ity o r the occu rrence o f h ip d is locatio n .
N o ben efi ts in any form ha ve be en rece ived or w ill b e rec eiv ed fro m a
c om m e rcial pa rty rela ted d ire ctly or in direct ly to the su bje ct o f th is
ar t icle .
R E F E R E N C E S
Bartlet t
MD,
W olf L S , Sh urt lef f
DB,
Stabell
LT . H ip
f lex ion
con tra ctu res : a c om pa riso n of m ea surem ent m e tho ds. A rch P hys
MedRehab i l 1 98 5; 6 6: 62 0-5 .
B eeker T W ,
Scheers
M M . Th e
h ip jo in t in spin a bifida a cco m p anied
by m y elo m e nin go ce e : a re vie w of the c ase s of a sp ina b ifida te am .
N eu ro O rth op ed ic s 1 98 6; 2 :8 7-9 4.
B ro ug hto n N S ,
Brougham
D I, C ole W G ,
Me n e l a u s
M B.
R eliability of
radio lo gic al m e asu rem en ts in the assessm e nt of the ch ild s h ip .
J
BoneJointSurg[Br]
1 98 9; 7 l-B :6 -8 .
D a nie ls L , W o rth ing ham C . Muscle tes tin g: te chn iqu es of manu a l
examination .
P hila delphia : W B S au nde rs, 19 86.
H eife r M M .
Join t m otion in ne w b orn s.
C /in O rth op
1 98 0; 1 48 :9 4-6 .
M cD o n a l d
C M , Ja ife K M , Shur t leif D B . A ssessm ent of m uscle s tre ngth
in children w ith m eningo m y elo cele : acc ura cy an d stability of
m ea surem ents ov er tim e.
A rch P h ys M ed Reh ab il
1 98 6; 6 7:8 55 -6 1.
S harra rd W JW . P os te rio r ilio pso as transp lan ta tion in th e trea tm ent o f
p ara ly t ic d islo ca tion o f the h ip .
J B one Jo in t Su rg [B r] 1964 ; 46-
B
:426-44.
Shurt lei f DB,
Me n e l a u s
M B,
Stahell
LT ,
e t * 1 . N atu ra l h is to ry o f flex ion
deform ity of the hip in m ye lod ysp las ia .
J P aed ia tr O rthop
1 9 8 6 ;
6:666-73.
V a nde r B rink
KD.
M yelo m e nin go cele. In : E d m o nson A S , C ren sha w
A H , eds. C am pbe lls o pe rative or tho pa edics. 6th ed. S t . L ou is, T h e
C V M osb y C om pany , 1980 :1 620-3 7 .