We used a three-dimensional rigid body spring model (RBSM) to compare the contact force distributions on the acetabular surface of the infant hip joint that are produced by three orthopedic treatments for developmental dysplasia of the hip (DDH). We analyzed treatments using a Pavlik harness, a generic rigid splint, and a spica cast. The joint geometry was modeled from tomography images of a 1-year-old female. The articular cartilage was modeled as linear springs connecting the surfaces of the acetabulum and the femoral head, whereas the femur and the hip bone were considered as rigid bodies. The hip muscles were modeled as tensile-only preloaded springs. The treatments with the Pavlik harness and the generic rigid splint were modeled for an infant in supine position with a hip flexion angle of 90 deg. Also, since rigid splints are often recommended when children are initiating their gait phase, we modeled the treatment with the infant in standing position. For the spica cast, we only considered the infant in standing position with a flexion angle of 0 deg, and the fixation bar at two heights: at the ankle and at the knee. In order to analyze the effect of the hip abduction angle over the contact force distribution, different abduction angles were used for all the treatments modeled. We have found that the treatments with the infant in supine position, with a flexion angle of 90 deg and abduction angles between 60 deg and 80 deg, produce a more homogenous contact force distribution compared to those obtained for the treatments with the infant in standing position.

References

References
1.
Morcuende
,
J.
, and
Weinstein
,
S.
,
2003
, “
Developmental Dysplasia of the Hip: Natural History, Results of Treatment and Controversies
,”
Controversies in Hip Surgery
,
Oxford University Press
, Oxford, UK, Chap. 1.
2.
Benavides
,
J. R.
, and
Figueroa
,
C. L.
,
2012
, “
Displasia de la cadera en desarrollo
,”
Rev. Colomb. Ortop. Traumatol.
,
26
(
1
), pp.
50
60
.
3.
Lee
,
M. C.
, and
Eberson
,
C. P.
,
2006
, “
Growth and Development of the Child's Hip
,”
Orthop. Clin. North Am.
,
37
(
2
), pp.
119
132
.
4.
Borges
,
J. L.
,
Kumar
,
S. J.
, and
Guille
,
J. T.
,
1995
, “
Congenital Dislocation of the Hip in Boys
,”
J. Bone Jt. Surg., Am.
,
77
(
7
), pp.
975
984
.
5.
Ottobock,
2016
, “
Tübingen Hip Flexion Orthosis
,”
Otto Bock HealthCare
GmbH, Duderstadt, Germany.
6.
Ramsey
,
P. L.
,
Lasser
,
S.
, and
MacEwen
,
G. D.
,
1976
, “
Congenital Dislocation of the Hip. Use of the Pavlik Harness in the Child During the First Six Months of Life
,”
J. Bone Jt. Surg., Am.
,
58
(
7
), pp.
1000
1004
.
7.
Genda
,
E.
,
Konishi
,
N.
,
Hasegawa
,
Y.
, and
Miura
,
T.
,
1995
, “
A Computer Simulation Study of Normal and Abnormal Hip Joint Contact Pressure
,”
Arch. Orthop. Trauma Surg.
,
114
(
4
), pp.
202
206
.
8.
Genda
,
E.
,
Iwasaki
,
N.
,
Li
,
G.
,
MacWilliams
,
B.
,
Barrance
,
P. J.
, and
Chao
,
E. Y.
,
2001
, “
Normal Hip Joint Contact Pressure Distribution in Single-Leg Standing—Effect of Gender and Anatomic Parameters
,”
J. Biomech.
,
34
(
7
), pp.
895
905
.
9.
Kreuz
,
P. C.
,
Fröhlich
,
S.
,
Lindner
,
T.
,
Olbertz
,
D.
,
Bader
,
R.
, and
Mittelmeier
,
W.
,
2012
, “
Biomechanical Evaluation of Different Abduction Splints for the Treatment of Congenital Hip Dysplasia
,”
Clin. Biomech. (Bristol, Avon)
,
27
(
9
), pp.
899
902
.
10.
Ardila
,
O. J.
,
Divo
,
E. A.
,
Moslehy
,
F. A.
,
Rab
,
G. T.
,
Kassab
,
A. J.
, and
Price
,
C. T.
,
2013
, “
Mechanics of Hip Dysplasia Reductions in Infants Using the Pavlik Harness: A Physics-Based Computational Model
,”
J. Biomech.
,
46
(
9
), pp.
1501
1507
.
11.
Huayamave
,
V.
,
Rose
,
C.
,
Serra
,
S.
,
Jones
,
B.
,
Divo
,
E.
,
Moslehy
,
F.
,
Kassab
,
A. J.
, and
Price
,
C. T.
,
2015
, “
A Patient-Specific Model of the Biomechanics of Hip Reduction for Neonatal Developmental Dysplasia of the Hip: Investigation of Strategies for Low to Severe Grades of Developmental Dysplasia of the Hip
,”
J. Biomech.
,
48
(
10
), pp.
2026
2033
.
12.
Abraham
,
C. L.
,
Maas
,
S. A.
,
Weiss
,
J. A.
,
Ellis
,
B. J.
,
Peters
,
C. L.
, and
Anderson
,
A. E.
,
2013
, “
A New Discrete Element Analysis Method for Predicting Hip Joint Contact Stresses
,”
J. Biomech.
,
46
(
6
), pp.
1121
1127
.
13.
Li
,
G.
,
Sakamoto
,
M.
, and
Chao
,
E. Y. S.
,
1997
, “
A Comparison of Different Methods in Predicting Static Pressure Distribution in Articulating Joints
,”
J. Biomech.
,
30
(
6
), pp.
635
638
.
14.
Fischli
,
S.
,
2007
, “
Simulation of Wrist Kinematics on the Basis of a Rigid Body Spring Model
,”
M.S. thesis
, Queen's University, Kingston, ON, Canada.
15.
Genda
,
E.
, and
Horii
,
E.
,
2000
, “
Theoretical Stress Analysis in Wrist Joint—Neutral Position and Functional Position
,”
J. Hand Surg.: Br. Eur.
,
25
(
3
), pp.
292
295
.
16.
Horii
,
E.
,
Garcia-Elias
,
M.
,
An
,
K. N.
,
Bishop
,
A.
,
Cooney
,
W. P.
,
Linscheid
,
R. L.
, and
Chao
,
E. Y. S.
,
1990
, “
Effect on Force Transmission Across the Carpus in Procedures Used to Treat Kienböck's Disease
,”
J. Hand Surg. Am.
,
15
(
3
), pp.
393
400
.
17.
Imura
,
S.
,
Akamatsu
,
N.
,
Azuma
,
H.
,
Sawai
,
K.
, and
Tanaka
,
S.
,
1993
,
Hip Biomechanics
,
Springer-Verlag
,
Tokyo, Japan
.
18.
Iwasaki
,
N.
, and
Genda
,
E.
,
1998
, “
Biomechanical Analysis of Limited Intercarpal Fusion for the Treatment of Kienböck's Disease: A Three‐Dimensional Theoretical Study
,”
J. Orthop. Res.
,
16
(
2
), pp.
256
263
.
19.
Majima
,
M.
,
Horii
,
E.
,
Matsuki
,
H.
,
Hirata
,
H.
, and
Genda
,
E.
,
2008
, “
Load Transmission Through the Wrist in the Extended Position
,”
J. Hand Surg. Am.
,
33
(
2
), pp.
182
188
.
20.
Schuind
,
F.
,
Cooney
,
W. P.
,
Linscheid
,
R. L.
,
An
,
K. N.
, and
Chao
,
E. Y.
,
1995
, “
Force and Pressure Transmission Through the Normal Wrist. A Theoretical Two-Dimensional Study in the Posteroanterior Plane
,”
J. Biomech.
,
28
(
5
), pp.
587
601
.
21.
Aldegheri
,
R.
, and
Agostini
,
S.
,
1992
, “
A Chart of Anthropometric Values
,”
J. Bone Jt. Surg. Br.
,
75
(
1
), pp.
86
88
.
22.
Drillis
,
R.
,
Contini
,
R.
, and
Bluestein
,
M.
,
1964
, “
Body Segment Parameters; A Survey of Measurement Techniques
,”
Artif. Limbs
,
8
, pp.
44
66
.
23.
Clauser
,
C. E.
,
McConville
,
J. T.
, and
Young
,
J. W.
,
1969
, “
Weight, Volume and Center of Mass of Segments of the Human Body
,” Aerospace Medical Research Laboratory Wright-Patterson Air Force Base, OH,
Report No. AMRL-TR-69-70
.
24.
WHO
,
2016
, “
The WHO Child Growth Standards
,”
World Health Organization
, Geneva, Switzerland.
25.
Swearingen
,
J. J.
, and
Young
,
J. W.
,
1965
, “
Determination of Centers of Gravity of Children, Sitting and Standing
,” Federal Aviation Agency Office of Aviation Medicine, Oklahoma City, OK,
Report No. AM 65–23
.
26.
Blankevoort
,
L.
,
Kuiper
,
J. H.
,
Huiskes
,
R.
, and
Grootenboer
,
H. J.
,
1991
, “
Articular Contact in a Three-Dimensional Model of the Knee
,”
J. Biomech.
,
24
(
11
), pp.
1019
1031
.
27.
Shim
,
V. B.
,
Pitto
,
R. P.
,
Streicher
,
R. M.
,
Hunter
,
P. J.
, and
Anderson
,
I. A.
,
2008
, “
Development and Validation of Patient-Specific Finite Element Models of the Hemipelvis Generated From a Sparse CT Data Set
,”
ASME J. Biomech. Eng.
,
130
(
5
), p.
051010
.
28.
Winters
,
J. M.
,
2012
, “
Hill-Based Muscle Models: A Systems Engineering Perspective
,”
Multiple Muscle Systems: Biomechanics and Movement Organization
, Springer-Verlag, New York, Chap. 5.
29.
Phillips
,
A. T. M.
,
2009
, “
The Femur as a Musculo-Skeletal Construct: A Free Boundary Condition Modelling Approach
,”
Med. Eng. Phys.
,
31
(
6
), pp.
673
680
.
30.
Seireg
,
A.
, and
Arvikar
,
R.
,
1975
, “
The Prediction of Muscular Load Sharing and Joint Forces in the Lower Extremities During Walking
,”
J. Biomech.
,
8
(
2
), pp.
89
102
.
31.
Hoy
,
M. G.
,
Zajac
,
F. E.
, and
Gordon
,
M. E.
,
1990
, “
A Musculoskeletal Model of the Human Lower Extremity: The Effect of Muscle, Tendon, and Moment Arm on the Moment-Angle Relationship of Musculotendon Actuators at the Hip, Knee, and Ankle
,”
J. Biomech.
,
23
(
2
), pp.
157
169
.
32.
Atalar
,
H.
,
Sayli
,
U.
,
Yavuz
,
O. Y.
,
Uraş
,
I.
, and
Dogruel
,
H.
,
2007
, “
Indicators of Successful Use of the Pavlik Harness in Infants With Developmental Dysplasia of the Hip
,”
Int. Orthop.
,
31
(
2
), pp.
145
150
.
33.
Gulati
,
V.
,
Eseonu
,
K.
,
Sayani
,
J.
,
Ismail
,
N.
,
Uzoigwe
,
C.
,
Choudhury
,
M. Z.
,
Gulati
,
P.
,
Aqil
,
A.
, and
Tibrewal
,
S.
,
2013
, “
Developmental Dysplasia of the Hip in the Newborn: A Systematic Review
,”
World J. Orthop.
,
4
(
2
), pp.
32
41
.
34.
Nakamura
,
J.
,
Kamegaya
,
M.
,
Saisu
,
T.
,
Someya
,
M.
,
Koizumi
,
W.
, and
Moriya
,
H.
,
2007
, “
Treatment for Developmental Dysplasia of the Hip Using the Pavlik Harness: Long-Term Results
,”
J. Bone Jt. Surg. Br.
,
89
(
2
), pp.
230
235
.
35.
Rincón
,
C. E. C.
,
2009
, “
Respuesta radiológica de los pacientes con displasia del desarrollo de la cadera al tratamiento con la Férula de Milgram
,”
M.S. thesis
, Universidad Industrial de Santander, Santander, Colombia.
You do not currently have access to this content.