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.
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
15.
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
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
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
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.
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”
35.
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
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)
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
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.
59.
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
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.
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 )
75.
76.
77.
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.
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
85.
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