Kinematics of The Subtalar and Tarsal Joints How the manipulation method of Ponseti works

conjunctionfrictionMechanics

Nov 13, 2013 (3 years and 11 months ago)

63 views

K
i
n
e
mat
i
c
s

of
T
h
e

S
u
b
ta
l
ar

a
n
d

Ta
r
s
al

J
oi
n
ts

H
ow

th
e

man
i
p
u
l
at
i
on

m
e
th
o
d

of
P
on
s
e
t
i

w
or
k
s


J
.

N
or
gr
ove

P
e
nny,

M
D
,

F
R
C
S
(
C
)


P
r
i
n
c
i
p
l
e
:

T
h
e

P
on
s
e
t
i

M
e
t
h
od

u
t
i
l
i
z
e
s

t
h
e

n
or
m
al

k
i
n
e
m
at
i
c
s

of

t
h
e

j
oi
n
t
s

s
u
r
r
ou
n
d
i
n
g
t
h
e

t
al
u
s

t
o
e
f
f
e
c
t

r
e
d
u
c
t
i
o
n

o
f

t
h
e

c
l
u
b
f
oot

d
e
f
or
m
i
t
y.


A
n
at
o
m
y


T
he

s
ubt
a
l
a
r

j
oi
nt

c
om
pl
e
x
i
s

one

of

t
he

m
os
t

c
om
pl
e
x
a
nd
l
e
a
s
t

unde
r
s
t
ood
j
oi
nt
s

i
n

t
he

body.

I
t

pl
a
ys

a

vi
t
a
l

r
ol
e

i
n
a
da
pt
i
ng

gr
ound

r
e
a
c
t
i
on
f
or
c
e

du
r
i
ng
ga
i
t

t
o
r
ot
a
t
i
on
o
f

t
he

l
ow
e
r

l
i
m
b
,

a
nd
a
da
pt
i
ng

a

m
obi
l
e

f
oot

t
o
i
nc
l
i
ne
d

gr
ound
s
ur
f
a
c
e
s
.




3
a
r
t
i
c
ul
a
r

f
a
c
e
t
s
:

pos
t
e
r
i
or
,

m
e
di
a
l
,

a
nt
e
r
i
or



2
f
unc
t
i
ona
l

c
om
pone
nt
s
:

o

T
a
l
o
-
c
a
l
c
a
ne
a
l

j
oi
nt



pos
t
e
r
i
o
r

a
r
t
i
c
ul
a
r

f
a
c
e
t

o

T
a
l
o
-
c
a
l
c
a
ne
o
-
na
vi
c
ul
a
r

j
oi
nt



t
he


a
c
e
t
a
bul
um

p
e
di
s


!

T
he

a
nt
e
r
i
or

a
nd
m
e
di
a
l

f
a
c
e
t

f
unc
t
i
on

w
i
t
h
t
he

t
a
l
o
-
na
vi
c
ul
a
r

j
oi
nt



T
a
l
o
-
c
a
l
c
a
ne
a
l

i
nt
e
r
os
s
e
ous

l
i
ga
m
e
nt

o

C
e
nt
e
r

of

r
o
t
a
t
i
on
f
o
r

t
he

s
ubt
a
l
a
r

j
oi
nt

o

C
ons
i
s
t
s

of

2
ba
nds

















T
he

P
os
t
e
r
i
or

a
r
t
i
c
ul
a
r

f
a
c
e
t

i
s

obl
i
que

i
n
t
he

c
or
on
a
l

pl
a
ne

a
nd
s
a
ddl
e

s
ha
pe
d
i
n
t
he

s
a
ggi
t
a
l

pl
a
ne
.


K
i
n
e
m
at
i
c
s

F
unc
t
i
ona
l
l
y,

a
l
l

t
he

bone
s

of

t
he

f
oot

m
ove

a
s

a

u
ni
t

a
r
ound
t
he

t
a
l
us
.

T
he
r
e

i
s

ve
r
y
l
i
t
t
l
e

i
nt
e
r
t
a
r
s
a
l

m
ot
i
on
.

(
I
nm
a
n

1976)



I
nt
e
r
os
s
e
ous

L
i
ga
m
e
nt


A
c
e
t
a
bul
um

P
e
di
s


T
he

f
oot

m
ove
s

a
r
ound
t
he

t
w
o
f
unc
t
i
ona
l

e
nt
i
t
i
e
s

of

t
he

s
ubt
a
l
a
r

j
oi
nt



t
he

t
a
l
o
-
c
a
l
c
a
ne
a
l

a
r
t
i
c
ul
a
t
i
on
a
nd
t
he

t
a
l
o
-
c
a
l
c
a
ne
o
-
na
vi
c
ul
a
r


a
c
e
t
a
bul
um

pe
di
s

,

w
i
t
h

t
he

i
nt
e
r
os
s
e
ous

l
i
ga
m
e
nt

a
s

t
he

c
e
nt
e
r

of

r
ot
a
t
i
on.


C
l
i
ni
c
a
l

r
e
l
e
va
nc
e
:

A
bduc
t
i
on
of

t
he

f
o
r
e
f
oot

d
ur
i
n
g
P
ons
e
t
i

m
a
ni
pul
a
t
i
on
c
a
us
e
s

a
bduc
t
i
on
of

t
he

c
a
l
c
a
ne
us
.

T
he

e
nt
i
r
e

f
oot
,

i
nc
l
udi
ng
t
he

c
a
l
c
a
ne
us
,

m
ove
s

a
r
ound
t
he

t
a
l
us
.


T
h
e

s
ubt
al
ar

ax
i
s

i
s

not

a

f
i
xe
d
poi
nt
,

bu
t

a

m
ob
i
l
e

a
xi
s

a
l
l
ow
i
ng
s
hi
f
t

a
nd
g
l
i
de

a
r
ound

t
he

c
ons
t
r
a
i
nt

m
e
c
ha
ni
s
m

of

t
he

i
nt
e
r
os
s
e
ous

l
i
ga
m
e
nt
s
.

(
H
us
e
n,

V
a
n
L
a
nge
l
a
nn)

I
nm
a
n
r
e
s
ol
ve
d
t
hi
s

m
obi
l
e

a
xi
s

a
xi
s

t
o
t
h
e

ob
l
i
q
u
e

p
l
an
e















T
he

m
ot
i
on

of

t
he

s
ubt
a
l
a
r

j
oi
nt

i
n
t
hi
s

ob
l
i
que

pl
a
ne

i
s

s
u
p
i
n
at
i
on

a
nd
p
r
on
a
t
i
on
.

S
u
p
i
n
a
t
i
on

c
ons
i
s
t
s

of

t
he

ki
ne
m
a
t
i
c
a
l
l
y
c
oupl
e
d

m
ot
i
ons

of

a
dduc
t
i
on
,

i
nve
r
s
i
on

a
nd
f
l
e
xi
on.

P
r
on
at
i
on

c
ons
i
s
t
s

of

t
he

ki
ne
m
a
t
i
c
a
l
l
y

c
oupl
e
d
m
ot
i
ons

of

a
bduc
t
i
on,

e
ve
r
s
i
on
a
nd
e
xt
e
ns
i
on
(
dor
s
i
f
l
e
xi
on)


N
or
m
al

s
u
b
t
al
ar

m
o
t
i
o
n
:



















S
u
b
t
al
ar

S
u
p
i
n
at
i
o
n





A
dduc
t
i
on



I
nve
r
s
i
on



F
l
e
xi
on



H
e
e
l

V
a
r
us

S
u
b
t
al
ar

P
r
on
a
t
i
on



A
bduc
t
i
on



E
ve
r
s
i
on



E
xt
e
ns
i
on
(
dor
s
i
f
l
e
xi
on
)



H
e
e
l

V
a
l
gus

K
i
n
e
m
at
i
c

c
ou
p
l
i
n
g


I
t

i
s

us
ua
l

f
o
r

o
r
t
hopa
e
di
c

s
ur
ge
ons

t
o
a
na
l
yz
e

j
oi
n
t

m
ot
i
ons

i
n

r
e
f
e
r
e
nc
e

t
o

t
he

s
t
a
nda
r
d
pl
a
ne
s

of

t
he

body:

c
or
ona
l
,

s
a
ggi
t
a
l
,

e
t
c
.

T
hus

w
e

ha
ve

a
dduc
t
i
on/
a
bduc
t
i
on,

i
nve
r
s
i
on
/
e
ve
r
s
i
on
a
nd
f
l
e
xi
on/
e
xt
e
ns
i
on
o
f

t
he

f
oo
t
.

B
ut

w
he
n

a

j
oi
nt

i
s

i
n

t
he

obl
i
que

pl
a
ne
,

a
s

w
i
t
h
t
he

s
ubt
a
l
a
r

j
oi
nt
,

a
l
l

t
he
s
e

m
ot
i
ons

a
r
e

i
ne
xt
r
i
c
a
bl
y
l
i
nke
d
t
o

one

a
not
he
r
,

or


ki
ne
m
a
t
i
c
a
l
l
y
c
oupl
e
d”
.

T
hus

a
bduc
t
i
on

of

t
he

c
a
l
c
a
ne
us

c
a
nnot

ha
ppe
n
w
i
t
hout

c
onc
ur
r
e
nt

e
ve
r
s
i
on
a
nd
e
xt
e
ns
i
on.

P
ons
e
t
i

s

t
e
c
hn
i
que

a
l
l
ow
s

c
or
r
e
c
t
i
on
by

s
i
m
ul
t
a
ne
ous
l
y
c
or
r
e
c
t
i
ng
t
he

m
ove
m
e
nt
s

i
n

t
he

ob
l
i
que

pl
a
i
n,

ut
i
l
i
z
i
ng
a
bduc
t
i
on

a
s

t
he

m
ot
or
.


T
he

P
ons
e
t
i

t
e
c
hni
que

i
s

a
t

onc
e

s
i
m
pl
e

a
nd
p
r
of
ou
nd.


T
he

f
or
e
f
oot

i
s

a
bduc
t
e
d
a
r
ou
nd

t
he

t
a
l
us
,

w
i
t
h

c
ount
e
r
pr
e
s
s
ur
e

a
ga
i
ns
t

t
he

he
a
d
of

t
he

t
a
l
us
,

s
i
m
ul
t
a
ne
ous
l
y
obt
a
i
ni
ng
a
bduc
t
i
on,

e
ve
r
s
i
on
a
nd
e
xt
e
ns
i
on
o
f

t
he

f
oot
,

a
nd
va
l
gus

of

t
he

he
e
l
.


M
a
nt
e
r

l
i
ke
ne
d
ki
ne
m
a
t
i
c
a
l
l
y
c
oupl
e
d
s
ubt
a
l
a
r

m
ot
i
on
t
o
t
he

he
l
i
c
oi
d
m
ot
i
on

of

a

s
c
r
e
w
.


F
a
r
a
be
uf

l
i
ke
ne
d
i
t

t
o

t
he

s
i
m
ul
t
a
ne
ous

pi
t
c
h,

ya
w

a
nd
r
ol
l

o
f

a

s
hi
p
on
t
he

s
e
a
.


T
he

m
i
s
t
a
ke

of

K
i
t
e

s

t
e
c
hni
que
,

a
nd
ot
he
r

s
i
m
i
l
a
r

m
e
t
hods
,

i
s

i
n
a
t
t
e
m
pt
i
ng
t
o

c
or
r
e
c
t

t
he

f
oot

s
e
que
nt
i
a
l
l
y,

b
r
e
a
ki
ng
dow
n
c
om
bi
ne
d

m
ove
m
e
nt
s

i
nt
o
t
he
i
r

c
om
pone
nt

pa
r
t
s
.

G
r
a
s
p
i
ng
t
he

c
a
l
c
a
ne
us

bl
oc
ks

i
t

s

nor
m
a
l

ki
ne
m
a
t
i
c
a
l
l
y
c
oupl
e
d
m
ot
i
on
.


C
or
r
e
c
t
i
on
c
a
n
t
he
n
onl
y
oc
c
ur

by
de
f
o
r
m
a
t
i
on
o
f

t
he

t
a
r
s
a
l

bone
s
.



M
axi
m
u
m

A
b
d
u
c
t
i
on
:


A
n
i
nf
a
nt

s

f
oo
t

nor
m
a
l
l
y
a
bduc
t
s

70
0
-
80
0
.

A

c
l
ub
f
oot

i
s

not

a
de
qua
t
e
l
y
c
o
r
r
e
c
t
e
d
unt
i
l

f
u
l
l

ab
d
u
c
t
i
on

i
s

obt
a
i
ne
d.

C
a
l
c
a
ne
a
l

e
xt
e
ns
i
on
(
dor
s
i
f
l
e
xi
on)

oc
c
ur
s

m
a
i
nl
y

dur
i
ng

e
xt
r
e
m
e

a
bduc
t
i
on.

C
or
r
e
c
t
i
ng
t
he

f
oo
t

t
o

ne
ut
r
a
l
,

or

f
unc
t
i
ona
l
,

pos
i
t
i
on
i
s

not

a
de
qua
t
e

t
o

a
c
c
om
pl
i
s
h
a
l
l

t
he

ki
ne
m
a
t
i
c
a
l
l
y
c
oupl
e
d
m
ot
i
ons

a
nd
r
e
l
a
ps
e

i
s

i
ne
vi
t
a
bl
e
.


















M
axi
m
u
m

A
b
d
u
c
t
i
on
:

O
bt
a
i
ns

f
ul
l

r
a
nge

of

m
o
t
i
on
o
f

t
he

s
ubt
a
l
a
r

j
oi
nt

R
e
duc
e
s

t
he

na
vi
c
ul
a
r

on
t
he

he
a
d
of

t
he

t
a
l
us

O
bt
a
i
ns

f
ul
l

e
ve
r
s
i
on
a
nd

pr
ona
t
i
on

O
bt
a
i
ns

dor
s
i
f
l
e
xi
on
of

t
he

c
a
l
c
a
ne
us

R
e
s
ul
t
s

i
n
he
e
l

va
l
gus


N
or
m
a
l

a
bduc
t
i
on
i
n

a

ba
by

















P
r
a
c
t
i
c
e

dr
i
l
l
s

w
i
t
h
e
l
a
s
t
i
c
i
z
e
d
f
oot

m
ode
l
s



P
r
i
nc
i
pl
e
:

T
he

e
nt
i
r
e

f
or
e
f
oot

m
ove
s

w
i
t
h
t
he

c
a
l
c
a
ne
us

a
r
ound
t
a
l
us


A
ppl
y
t
he

D
oubl
e

H
a
nd
H
ol
d
.

D
o

not

bl
oc
k
t
he

c
a
l
c
a
ne
us
.

A
bduc
t

t
he

f
or
e
f
oot

a
nd
obs
e
r
ve

P
r
ac
t
i
c
al

appl
i
c
at
i
on:


C
or
r
e
c
t
i
on
of

t
he

r
e
a
r
f
oot

&

m
i
df
oot

c
a
n
be

a
c
c
om
pl
i
s
he
d
by
a
bduc
t
i
on
of

t
he

f
or
e
f
oot

A
bduc
t
i
on
pr
e
s
s
ur
e

on
t
he

f
i
r
s
t

m
e
t
a
t
a
r
s
a
l

l
e
ve
r

c
a
n

m
ot
or


m
ove
m
e
nt

o
f

t
he

c
a
l
c
a
ne
us



P
r
i
nc
i
pl
e
:

A
bduc
t
i
on
a
nd

E
ve
r
s
i
on
a
r
e


K
i
ne
m
a
t
i
c
a
l
l
y
C
oupl
e
d”



E
l
e
va
t
e

t
he

f
i
r
s
t

r
a
y



A
bduc
t

t
he

f
or
e
f
oot



O
bs
e
r
ve

r
e
l
a
t
i
ons
hi
p
of

f
or
e
f
oot

t
o
l
ong

a
xi
s

of

t
he

t
i
bi
a



O
bs
e
r
ve

t
he

obl
i
que

pl
a
ne

of

t
a
l
o
-
n
a
vi
c
ul
a
r

m
ot
i
on


P
r
ac
t
i
c
al

A
ppl
i
c
at
i
on
:

A
s

t
he

f
oot

i
s

a
bduc
t
e
d
,

t
he

i
nve
r
s
i
on
(
a
ppa
r
e
nt

s
upi
na
t
i
on)

s
pont
a
ne
ou
s
l
y
c
or
r
e
c
t
s

t
o
ne
ut
r
a
l


T
he

f
or
e
f
oot

i
s

ne
v
e
r

pr
ona
t
e
d


P
r
i
nc
i
pl
e
:

A
bduc
t
i
on
o
f

t
he

f
or
e
f
oot

s
pont
a
ne
ous
l
y
c
or
r
e
c
t
s

t
he

he
e
l

va
r
us



L
ook
a
t

t
he

f
oot

m
ode
l

f
r
om

b
e
hi
nd



A
bduc
t

t
he

f
or
e
f
oot



N
ot
e

t
he

c
a
l
c
a
ne
us

m
ovi
ng
f
r
o
m

va
r
us

t
o

va
l
gus



N
ot
e

c
a
l
c
a
ne
us

m
ovi
ng
a
w
a
y
f
r
om

f
i
bul
a

a
nd

s
t
r
e
t
c
hi
ng
of

t
he

c
a
l
c
a
ne
o
-
f
i
bul
a
r

l
i
ga
m
e
nt


P
r
ac
t
i
c
al

A
ppl
i
c
at
i
on
:

W
i
t
hout

t
ouc
hi
ng
t
he

c
a
l
c
a
ne
us
,

t
he

he
e
l

s
pont
a
ne
ous
l
y
c
om
e
s

out

of

va
r
us

a
s

t
he

f
oot

i
s

a
bduc
t
e
d.


#1
T
he


C
a
l
c
a
ne
o
-
P
e
di
s

B
l
oc
k”


#2
K
i
ne
m
a
t
i
c

c
oupl
i
ng

#3
H
e
e
l

va
r
us



P
r
i
nc
i
pl
e
:

A
bduc
t
i
on
a
nd

E
xt
e
ns
i
on
(
do
r
s
i
f
l
e
xi
on)

of

t
he

s
ubt
a
l
a
r

j
oi
nt

a
r
e


k
i
ne
m
a
t
i
c
a
l
l
y
c
oupl
e
d”



A
bduc
t

t
he

f
or
e
f
oot



O
bs
e
r
ve

t
he

a
nt
e
r
i
or

p
r
oc
e
s
s

of

t
he

c
a
l
c
a
ne
us
;




f
r
om

t
he

f
r
ont




f
r
om

t
he

s
i
de


P
r
ac
t
i
c
al

A
ppl
i
c
at
i
on
:

A
s

t
he

f
oot

i
s

m
ax
i
m
al
l
y

a
bduc
t
e
d
,

t
he

s
ubt
a
l
a
r

j
oi
nt

s
pont
a
ne
ous
l
y
e
xt
e
nds

a
nd
dor
s
i
f
l
e
xi
on
i
m
pr
ove
s

w
i
t
hout

r
oc
ke
r

bot
t
om

r
i
s
k

R
e
s
e
r
ve

t
e
not
om
y
f
or

ank
l
e

dor
s
i
f
l
e
xi
on
a
f
t
e
r

s
ubt
a
l
a
r

dor
s
i
f
l
e
xi
on
i
s

m
a
xi
m
i
z
e
d



K
i
t
e

s

m
i
s
t
ak
e


G
r
a
s
p
t
he

c
a
l
c
a
ne
us

s
o
a
s

t
o
bl
oc
k
i
t

f
r
om

a
bduc
t
i
ng

A
bduc
t

t
he

f
or
e
f
oot

H
ow

i
s

t
he

f
o
r
e
f
oot

a
dduc
t
us

c
or
r
e
c
t
i
on
obt
a
i
ne
d?


B
l
oc
ki
ng
t
he

c
a
l
c
a
ne
us

f
r
om

a
bduc
t
i
ng

c
a
us
e
s

i
a
t
r
oge
ni
c

de
f
or
m
a
t
i
on

of

t
he

m
i
dt
a
r
s
a
l

bo
ne
s

a
nd
j
oi
nt
s
!

T
hi
s

c
r
e
a
t
e
s

t
he


be
a
n
s
ha
pe
d
f
oot

.


4.

S
ubt
a
l
a
r

dor
s
i
f
l
e
xi
on

5.


K
i
t
e
s

M
i
s
t
a
ke



R
e
f
e
r
e
nc
e
s


1.

C
l
os
e
,

J
R
.
,

I
nm
a
n
,

V
T
.
,

P
oo
r
,

P
M
.
,

T
odd
,

F
N
.

(
19
67)

T
he

F
unc
t
i
on
o
f

t
he

S
ubt
a
l
a
r

J
oi
nt
.

C
l
i
n.

O
r
t
hop
.

50:

159.

J
a
n
-
F
e
b.

2.

H
us
on
A

(
1991)
.


F
unc
t
i
on
a
l

a
na
t
om
y

of

t
he

f
oot
.


I
n:


J
a
hs

J
H

(
e
d)

D
i
s
or
de
r
s

of

t
he

f
oot

a
nd
a
nkl
e
,

2nd

E
d,

vol
.

1
.

S
a
unde
r
s
,

P
hi
l
a
de
l
p
hi
a
.

3.

I
nm
a
n,

V
T
.

(
1976)

T
he

J
oi
nt
s

of

t
he

A
nkl
e
.

W
i
l
l
i
a
m
s

&

W
i
l
ki
ns

C
o.

4.

K
a
pa
ndj
i
,

I
A


T
he

P
hys
i
ol
ogy
o
f

t
he

J
oi
nt
s
.

2
n
d
.

E
d
.

C
hur
c
hi
l
l

L
i
vi
ngs
t
one

5.

K
i
t
e

J
H

(
1964)

T
he

c
l
ub
f
oot
.


G
r
une

&

S
t
r
a
t
t
on
,

N
e
w

Y
or
k
L
ondon
.

6.

K
i
t
e
,

J
H
.

(
1972)


N
onope
r
a
t
i
ve

T
r
e
a
t
m
e
nt

of

C
ong
e
ni
t
a
l

C
l
ubf
oot
.

C
l
i
n.

O
r
t
hop.

84:

29.

M
a
y
1972

7.

M
a
nt
e
r
,

J
T
.

(
1941)

M
ove
m
e
nt
s

of

t
he

S
ubt
a
l
a
r

a
nd

t
r
a
ns
ve
r
s
e

T
a
r
s
a
l

J
oi
nt
s
.

T
he

A
na
t
om
i
c
a
l

r
e
c
o
r
d,

V
ol
.
80
,

N
o
.
4.

8.

P
ons
e
t
i

I
V

(
1996
)

C
onge
ni
t
a
l

c
l
ub
f
oot
.


F
unda
m
e
n
t
a
l
s

of

t
r
e
a
t
m
e
nt
.


O
xf
or
d

U
ni
ve
r
s
i
t
y
P
r
e
s
s
,

O
xf
or
d
,

N
e
w

Y
or
k.

9.

P
ons
e
t
i

I
V
(
1997)
.


C
om
m
on
e
r
r
or
s

i
n

t
he

t
r
e
a
t
m
e
nt

of

c
onge
ni
t
a
l

c
l
ubf
oot
.


I
nt
e
r
na
t
i
ona
l

or
t
hopa
e
di
c
s

21:
137
-
41

10.

S
a
r
r
a
f
i
a
n,

S
K

(
1993)

B
i
om
e
c
ha
ni
c
s

of

t
he

s
ubt
a
l
a
r

j
oi
nt

c
om
pl
e
x
.

C
l
i
n
.

O
r
t
hop
.

290
:

17,

M
a
y
1993

11.

S
a
r
r
a
f
i
a
n,

S
K

F
unc
t
i
ona
l

A
na
t
om
y
o
f

t
he

F
oot

a
nd
A
nkl
e
.

2
n
d
.

E
d
.

J
.
B
.
L
i
ppi
nc
ot
t

C
om
pa
ny

12.

V
a
n
L
a
nge
l
a
nn,

E
J
.

(
1983)


A

K
i
ne
m
a
t
i
c
a
l

A
na
l
ys
i
s

of

t
he

T
a
r
s
a
l

J
oi
nt
s
.

A
c
t
a

O
r
t
hop.

S
c
a
nd.
,

54
(
S
upp.

204
)