Preoperative and postoperative hamstrings and iliopsoas lengths for children with cerebral palsy during walking

162

Abstracts

I Gait & Posture

7 (1998)

144-190

Session Eleven: Posture and Balance Sara Edwards.

Crouch

gatt.

BS. St&en Child~Memorial

a common

Vattk&iLMs. Medical

Claudia Center.

Keb-Lenate, PT. Luciano Chicago. Illinois 6061 I

Intraductlon among childten

abnamtality

Dies.

MD

Gad Changes with

cerebral

palsy,

wreew Ten

to determine pabents

(20

the efficacv sides)

with

of the various crouch

gut

orccedures.

(knee

ilerion

> than

20 degrees

throughout

cycle)

were included io this studv. All walked barefwt wtthout external ~wport. Gatt attalvsis data was collected prior to and appmximately one year following surgery using a six camera VICON motion system and physical therapy assessment. Five children had their hamstrings(H) lengthened (mean age preop. 8.8 years. postop, 10.5 years) and five had both hamstrmg lengthenrngs and diopsoas (WIP) recessions above the brim (mean age preop. 8.3 yrs; postop 10.8 yrs). Three dtmenstonal musculoskeletal modebog was used to evaluate the psoas and hamstring lengths during walking.’ Selected knee, bip and pelw pre and port-op kinematxs and mwcle lengths were examined using paired t-test procedures ReSU1t.S Table l outlines the muscle length results. Figure I shows two repreaentatlve patients’ hamstring length. Comparison of pre vs. post surgical muscle lengths showed hamstongs were longer for bath groups (p=.O6 for the H group) at mittal contact (IC) post-op. At midstance the hamstrmgs were significantly longer post-op for both groups and the pre and pat iliopaoa length was ~ioular for both tdt mcreased and minimum of the H group sod 60%

groups. Maximum iliopsoas length hip extension decreased slgmticantly of the HilP group demonstrated

decreased for H group as pelvic (Table I). Pre-op 80% percent normal or longer hamstring, dt

mld%ance compared to normal. Post-op 70% of the H group showed hamstrmg lengths longer than one stand&d dewman above normal related to the increased knee extension. hip flexton and anterior oelvic tdt Pre-OP 60% of both groom demonstrated d~opsoas lengths shorter than one andnrd deviation below normal. Both patient group, Showed greater knee e~tens!on at lC (Figure 2) The HilP patlent\ demonstrated sngmficantly improved mmmum

_

wnce

pharc

knee

flexton,

mean %toce

phase knee tlexion

and mmmuon

on Ody

Floors

1s characterized

primarily by excessive knee flexian during stance phase. Tight or spastic hamstrings are often imphcated as the cause of crouch gait pattern, hence, patients dtsplaying a persistent crouch are often treated with surgical lengthening the hamstrings. Computer modebog of crouch gait has suggested that short hip flexors may be a more co-n source of crouch gait.’ ’ Tbe purpose of this study was to exannx both the muscle lengths and kinemauc data of patients who have had combinations of hamstring and hamstriog/iliopsoes lengthenings before and after

hip flexion

lnformatlon

Rohae Mwng Sciences and Systems Morgan State Untversity

Baltimore, I. INTRODUCTION Stamws showed that shp acc,dents are one of the leadmg occupat~anal accidents around the world In dtscussmg the preventton ofthese

possible accadents.

MD

Depanment

21239

strateg~ea for three factors

to affect slips are. (I) biomechanical factors, (2) floor surface factors and (3) psychologxal factors m walking Of these three factors. Manning (1983) showed that the most frequent and severe causes of slipping accidents were low friction between the shoe and underfoot surface contamioated with water, u, oil. food scraps, or small objects To smwlate human gait from the knee down to measure fnctton with an articulated strut, researchers (GrOnqvist. 1989, Bidanda, 1990) stmulated only forward slips because studies (Perkins 1983. and Strandberg 1983) showed that backward slips were not dangerous even though they happened during take off of the toe However, the Shoe and Allied Trades Research Assonation’s (SATRA) new friction test protocol required the dynamic co&icteot of friction (DCOF) with a backward toe slip

~.._. Figure

~..---

2 Backward

and Lateral

Slips

(Wilson, 1990) Therefore, this study was conducted to investigate how gait WBS changed on oily floors and whether backward shps also played major roles on oily floors 2. METBODOLDGY

in creatmg

dangerous

slips

2 I Autwatus Two simulated floors (250 x 30 x 2 5 cm) were used, dry ceramic and oily steel The ExperVision motion analysis system with 60 Hz data collection rate was used The suspension

amt speedof a fall arresting rig WBEfixed cd I 33 m/s because

it is the closest

available

speed by the rig compared

to the normal

walking

for male adult

speed (I 36 cm/s)

(20 to

59 years old) by Waters (1988) 2 2 Procedure Five volunteers, attached retro-reflectors

at

heel and toe of the let? shoe. walked on the floor samples while wearing a harness from the ng The exact location ofthe heel was 2 5 cm from the rear-edge and the bottom of the shoe

The

couple

hamstrings. hamstring midstance but also

between

hip

and

the

DlrCWkUJ knex through

the

hamstrings,

not

necessarily

“short”

has been suggested to be a primaty source of crouch gait in cerebral palsy. Medial lengthenings were perfomud on eight of ten limbs that were nomxd or longer at to addtw increased

IUIP patients stable to allow Comparison lengthening

the

hip

the crouch gait. The flexion and pelvic

hip extension the hamstring of these cm have

H gmttp patients tilt and decteawd

inctnued while pelvic length gained sorgically

two surgical groups on the crouch gait

showed impmved maaimuttt psoas

knee kinematics length. For the

tilt and maximum pas length remained to be realized pre&mittantly at the knee.

provides sot&z indication of the pattern. panicuIarly at midstance.

effect pelvic

iliopsoa and hip

position appear to be crucial during midstance phase and “short” hamstrings may play a more prominent role m terminal swiog/ioitial contact knee tlexion wbett maximom hamstrirtg length during gait is expected. Tbe consequence that hamstring lengthening has on the pelvis and hip may compromise the dewed comction of the crouch gait. Pelvic and bip positioo and maximum iliopsoas length during gait may be maintamed with hip extensor strengthening. combined presently

iliopsoas examming

recession wth hamstring lengthening. or iliopsoas recession alone. We are the effect of iliopsoas recession alone on those patients with crouch gait.

Without hamstring be plausible and extension moment

lengthening, greater hp extension and posterior position of the pelvis may crouch gait could be addressed by taking advantage of the greater htp arm to allow the often normal or even longer hamstrings to be appreciated

distally at the knee. Muscle mcdebng may not only contribute to crouch gut but may also help identtfy different periods of the gait cycle. References

help tweak the multiple the different sources

factors that cm of crouch during

Figure

3 Shp DIrections

4. DISCUSSION Subjects significantly decreased their stride length about 10 cm on oily steel compared to dry ceramic, resulting m an abnormal gait

The toe target was placed 2 5 cm above the sole, on the outer edge All subjects wore the same shoes with B PVC sole Data collection WLE lasted for 3 seconds

This decreased SL increased cadence the fixed walking velocity, which in turn deteriorate their regaining balance on oily floors due to less stable-post&e For the first lateral sklddinn from multi-

3. RESULTS For this study, two dependent variables were chosen stride length (SL) and shp distance (SD) Stride length was detined as the hnear distance in the direction of progression

lateral shddings, subJects triedto regain their halattce right after they detected skidding (it only took 0 2 seconds) To do so, subiects mtentionally moved their center of go&y forward to catch their skidding motion That

between su~cesswe points of foot-to-floor contact of the same foot The foot-to-floor contacting point was defined as the lowest m the vertical direction of heel movement

jerk movement caused dram& slip dIrection change sod resulted in even longer and more dangerous slips. In conclusion. multi-lateral slips would be

point

pattern

becauseof

For strtde lengths. dry ceramic (1 44 m) was intherangeofnormaISL(1511+0141m)by Waters (1988) but SL for oily steel (I 34 m) was sig&i&ly shorter than lower limit (1 37

more dattgerws because subjects were found to he more vulnerable when their balance were very unstable on oily floors due to SL reduction and intentional forward movement of center of

m) by Waters baxd multiple comparison

gravity In other words, found to he as important

on Student-Newman-Keul test

Slip distance was calculated to show how sbppery the sample floors were The longer, the more slipwry. To calculate slip distance. a horizon&i vi vertical plot was dram to find forward slim while a horizontal vs IateraI plot was drawn’for backward and lateral slips Figure I shows two gait cycles The plateau m between each gait cycle represented a slip because no vertical difference was detected while horizontal displacement increased In other words, no plateau was found without a”y

backwmd slips were as forward slips or

even m”re important in the friction test pr0t”C4ll 5. REFERENCES Bidanda et al , Development of a micm conlputer based slip resistance tester, 0tttcute.m in IE Jowl& 1991, (unpublished) GronqviJt et al., An apparatus and a method for deermining the slip resistawe of shoes and floor$ Ersonomics, 32,9?9-995, 1989

and lateral shps would be parallel

Manning, Death and inIuries caused by rllppmg. trappmg and falling. Emonomics. 26. I, 3-9. ,983 Perkins et al Current work on sole slip

along the x’ax~s After calculatmg shp d&nce and direction, figure 3 was developed to find a relationshtp between slip dlrection and shp severity No sbps were found on dry ceraonc There were neither forward nor backward shps mvolved It would better to be satd that all slips were lateral sklddmg foot motmns Two lateral sklddings were found. um- lateral (vbo and vbb) and multi-lateral sktddmgs (vbs and vca) No slips were detected from one subIect

resistance, Ergonomu. 19. 193-196, 1983 Strandberg. Dn acadent analysts and slip reststance meaaurementa. Eraonomics, 26. I, 11-32, 1983 Waters et al, Energy-speed relationrhtp of walking standard tables &.!@I&of Orthooaexiic Research, 6.215-222. 1988 Wilson, Development of SATRA slip test and tread pattern design guideline, ASTM STP ,103 113-123. 1990

shps F,gure 2 shows backward WIthout sbps. the heel marker