NEW CONCEPTS IN PERTHES DISEASE

1. DR.GIRISH MOTWANI
M.S.ORTHOPAEDICS(GOLD MEDALIST)
FELLOW IN PAEDIATRIC
ORTHOPAEDICS
B.J.WADIA HOSPITAL FOR CHILDRENS
Current trends in the
Management of Legg-Calvé-
Perthes Disease

2. Perthes disease
even after 100 years it remains an
enigma shrouded in controversies
 Pathology first……..

3. PATHOGENESIS
4 stages on the basis of evolution of disease
 Stage of Avascular Necrosis
 Stage of Revascularization / Fragmentation
 Stage of Ossification / Healing
 Remodeling / Residual stage

4. PATHOGENESIS
Stage of Avascular Necrosis
Ischemia
A part ( anterior) or whole of capital
femoral epiphysis is necrosed.
On X-ray –
 The ossific nucleus looks smaller
 Classically of Perthes’, looks
dense
 The articular cartilage remains
viable & becomes thicker than
normal
– increased joint space.

5. PATHOGENESIS
Stage of REVASCULARIZATION / FRAGMENTATION
 Ingrowths of highly vascular & cellular connective tissue.
 Necrotic trabecular debris is resorbed & replaced by vascular
fibrous tissue the alternating areas of sclerosis and
fibrosis appear on X- ray as fragmentation of epiphysis.
 New immature bone laid on intact
necrosed trabeculae by creeping
substitution further increases
the density of ossific nucleus on
X-ray.

6. It is at this stage that there is
collapse and loss of structural
integrity of the femoral head as
it is sort of softened due to bone
resorption, collapse of necrotic
bone and persistence of
fibro-vascular tissue leading to
deformation of epiphysis.
The femoral head may extrude from the acetabulum
at this stage.
Stage of REVASCULARIZATION / FRAGMENTATION (contd.)

7. PATHOGENESIS
Stage of Ossification / Healing
New bone starts forming
and epiphyseal density
increases in the lucent
portions of the femoral head.

8. PATHOGENESIS
 Remodeling / Residual stage
This is the stage of remodeling and there is no
additional change in the density of the femoral
head.
Depending on the severity of the disease the
residual shape of the head may be spherical
or distorted.

9.  Gill(1940) – metaphyseal necrosis & lucencies
(“holes of decalcification”)

10. X-Ray
 Cresent Sign or
Salters sign or
Caffey’s sign

11.  Ponseti – cystic
changes in neck
 Prognostic value –
poor outcome

12.  Sagging rope sign
 radiodense line in prox
femoral metaphysis
 Metaphyseal response to
physeal damage

13.  Premature physeal closure
 With central arrests:
 Round head
 Short neck
 Troch overgrowth
 With lateral arrest:
 Femoral head tilted Laterally
 Elongation of medial neck
 Overgrowth of troch

14.  Morphological changes in acetabulum in perthes
described by BENJAMIN JOSEPH (JBJS 1989)
 Osteoporosis of acetabular roof
 Irregularity of contour
 Premature fusion of triradiate cartilage (
bicomparmentalisation)
 Hypertrophy of articular cartilage & changes in
dimension

16. On plain xray -
bicompartmental
acetabulum appears to
be composed of 2 arc
partly overlapping each
other – interpreted as the
subluxated femoral head
articulating only with the
lateral half of the
acetabulum moulding it
into 2 compartments

17. Whom should we treat actively??
 Extent of disease
 Stage of disease
 Head at risk signs
 Age

18. Extent of disease
 Catterall
 Salter & thompson
 Herring
 Elizabeth

19. Catterall classification
 Catterall Group I: Involvement only of the anterior epiphysis
(therefore seen only on the frog lateral film)
 Catterall Group II: Central segment fragmentation and collapse.
However the lateral rim is intact and thus protects the central
involved area.
 Catterall Group III: The lateral head is also involved or
fragmented and only the medial portion is spared. The loss of
lateral support worsens the prognosis.
 Catterall Group IV: The entire head is involved.
 Catterall's classification has a significant inter and intra observer
error.

20. Catterall:
 I – anterior epiphysis
 II – up to 50% with collapse
 III – only small posterior
portion not involved
 IV – whole head involvement

21. Catterall I:

22. Catterall II:

23. Catterall III:

24. Catterall IV:

25. Catterall classification
 Groups I and II had a good prognosis (in 90%)
and required no intervention.
 Groups III and IV had a poor prognosis (in 90 %)
and required treatment.

26. Salter and Thompson Classification
 Salter and Thompson recognized that Catterall's
first two groups and second two groups were
distinct and therefore proposed a two part
classification.
 Salter & Thompson Group A: Less than 1/2
head involved.
 Salter & Thompson Group B: More than 1/2
head involved.
 Again the main difference between these two
groups is the integrity of the lateral pillar.

27.  extent of the fracture (line) is less than
50% of the superior dome of the
femoral head
› good results can be expected.

28.  Extent of the fracture is
more than 50% of the
dome,
› fair or poor results can
be expected

29. Stulberg classification

30. (Herring) Lateral Pillar Classification
 Lateral Pillar Group A: There is no loss in height of the lateral
1/3 of the head and minimal density change. Fragmentation
occurs in the central segment of the head.
 Lateral Pillar Group B: There is lucency and loss of height in
the lateral pillar but not more that 50% of the original
(contralateral) pillar height. there may be some lateral extrusion
of the head.
 Lateral Pillar Group C: There is greater than 50% loss in the
height of the lateral pillar. The lateral pillar is lower than the
central segment early on.

31. Herring A:

32. Herring B: Herring C:
And now there is “B/C Border” since
the ability to differentiate B / C
proved elusive

33. JBJS .

34. Conclusion of article :
Lays importance on the structural integrity of
superolateral – the principal load bearing part of
the head
 “Outcome relates strongly to the integrity of the
lateral pillar”

36. Conclusion was……
 Herring A - all do well without without treatment
 Herring B – bone age <8 years :uniform outcome
irrespective of type of treatment.
 Herring B –bone age>8 years:surgery >brace
 Herring C- bone age <8years: surgery > brace
 Herring C –bone age > 8 years: poor outcome
irrespective of type of containment

37. Supporting articles:
 Jbjs 2008

39. “HEAD AT RISK SIGNS”
 Gage's sign :- a V shaped lucency in the lateral epiphysis.
 Lateral calcification (lateral to the epiphysis) (implies loss of
lateral support)
 Lateral subluxation of the head. (implies loss of lateral support)
 A horizontal growth plate. (implies a growth arrest
phenomenon and deformity)

40. Lat subluxation / Calcification lat to
epipiphysis – HEAD AT RISK

41. GAGE`S SIGN

44. Salters extrusion Index
 If AB is more
than 20% of CD
it indicates a
poor prognosis

45. Modified Elizabethtown
classification
 Stage Ia: Part or
whole of the
epiphysis is
sclerotic. There is
no loss of height of
the epiphysis.

46. Modified Elizabethtown
classification
 Stage Ib: The
epiphysis is
sclerotic and
there is loss of
epiphyseal
height. There is
no evidence of
fragmentation of
the epiphysis.

47. Modified Elizabethtown
classification
 Stage IIa: The
sclerotic epiphysis
has just begun to
fragment. One or
two vertical fissures
are seen in either
the AP or the lateral
view

48. Modified Elizabethtown
classification
 Stage IIb:
Fragmentation is
advanced. No new
bone is visible
lateral to the
fragmented
epiphysis.

49. Modified Elizabethtown
classification
 Stage IIIa: Early
new bone
formation is visible
on the periphery of
the necrotic
epiphysis and
covers less than a
third of the width of
the epiphysis

50. Modified Elizabethtown
classification
 Stage IIIb: The
new bone is of
normal texture and
has grown over a
third of the width of
the epiphysis.

51. Modified Elizabethtown classification
 Stage IV the healing is complete and there is no
radiologically identifiable avascular bone.

57. Containment
 Importance ?
 Timing ?
 How long containment ?
 Candidates ?
 Types ?
 Results ?

58. Rational behind "containment"
 Containment of the head within the acetabulum is
reported to encourage spherical remodelling during the
reossification and subsequent phases.
 However if there is total head involvement and the lateral
pillar collapses then the effect of containment is probably
less.
 Therefore it seems that the extent of involvement of the
head is the critical factor and containment simply
optimizes the situation.

60. Timing of containment:
Deformation occurs during the phase of
revascularization (fragmentation) & early
regeneration (ossification).
It would therefore follow that if the containment is
to succeed, it would need to be performed before
the late phase of fragmentation, i.e., in stages of
AVN or early fragmentation

61.  How long containment?
Needs to be ensured until the healing process
and beyond the stage where epiphysis is
vulnerable to deformation that is until the late
stage of regeneration phase ( 2 yrs)

62.  Methods of CONTAINMENT OF
HEAD
(a) Conservative methods
(b) Surgical methods

63. CONSERVATIVE METHODS
Weight relief & rest
In the past, treatment was primarily directed at avoiding
weight by bed rest for prolonged period (up to 2 yrs) or
weight relieving calipers to prevent head deformation.
Little evidence for efficacy.
Containment by bracing & casting
Plaster cast in abd. & internal rotation – broomstick casts
Braces to keep hip in desired position.
Weight bearing is allowed in braces.
Casts - temporary form of containment till definitive
treatment undertaken.

64. Treatment (Orthosis)
 Non Ambulatory weight releiving
1. Abduction broomstick plaster cast
2. Hip spica cast
3. Milgram hip abduction orthosis
 Ambulatory Both limbs included
1. Petrie Abduction cast
2. Toronto orthosis
3. Newington orthosis
4. Birmingham brace
5. Atlanta Scotish Rite Brace
 Ambulatory unilateral
1. Tachdjian trilateral socket orthosis

65. Treatment (Orthosis)
 Atlanta Scotish Rite
Brace

66. Atlanta Scotish Rite Brace

67. Newington orthosis

68. Birmingham brace

69.  Toronto Brace

70.  Tachdjian trilateral
socket orthosis

71. Treatment (Orthosis)
 Orthotic treatment is discontinued when the
disease enters the reparative phase and healing
is established.
 The radiographic evidence of healing are
1. Appearance of regular ossification in the femoral head.
2. Increased density of femoral head should disappear.
3. Metaphyseal rarefaction involving the lateral cortex of
the metaphysis should ossify.
4. There should be intact lateral column.
5. There should be normal trabecular bone in the
epiphysis.

72. HIP ABDUCTION BRACE / CASTS
Broom stick casts
Scottish Rite orthosis

73. BROOMSTICK CASTS

74. SURGICAL METHODS
Femoral osteotomy – S/T or I/T.
Innominate osteotomy – Anterolateral coverage
Operative reconstruction provides the advantage of
improved containment & early mobilization and is a
preferred method.
No end point for discontinuing the treatment because the
improved containment is permanent.
Short term studies suggest an improvement in the natural
course of the disease process with femoral osteotomy.
(Salter’s )

78. FEMORAL OSTEOTOMY
 Up to 12 years of age an open wedge osteotomy
may be performed without the risk of delayed union /
non-union.
Also the amount of shortening is minimized.
 Pre-requisites – near normal hip movements.

79. PELVIC OSTEOTOMY
 Redirectional Osteotomy
 Salter’s osteotomy to
reorient the acetabulum
 Shelf Operation
 To create a bony shelf to
cover the extruded part of
the epiphysis.
 Displacement Osteotomy
 Chiari osteotomy is another
way to improve the
coverage.

80. Perthes after primary healing……

83. Hinge abduction
 The Articular surface of the head and acetabulum are not
concentric.
 The femoral head hinges at the acetabulum when limb is
abducted – the medial joint space is increased.
 Best diagnosed on arthrography.

84. TREATMENT
Reconstructive procedures
 Valgus extension osteotomy
indication -hinge abduction of hip
 Cheilectomy
indication – malformed femoral head with lateral
protuberance Coxa plana
 Chiari osteotomy
indication – malformed femoral head with lateral
subluxation
 Trochanteric advancement
indication – premature capital femoral physeal arrest
 Greater trochanteric epiphysiodesis
indication – premature capital femoral physeal arrest
 Shelf augmentation procedure
indication – coxa magna coxa magna & lack of acetabular
coverage

86. Treatment
Treatment is divided into 3 phases
 Initial Phase – restore & maintain mobility
 Active Phase – Containment and maintainance of full
mobility.
 Reconstructive phase – correct residual deformities.

87. Prognostic Factors
1. Age at diagnosis
2. Extent of involvement
3. Sex
4. Catterall “head at risk” clinical signs
 Clinical
1. Progressive loss of hip motion
2. Increasing abduction contracture
3. Obese child

88. So finally…. before planning surgery,
first think of atleast 4 things …..
 Herring stage
 Pathological stage
 Age
 Range of motion