PERTHES' DISEASE - Yorkhill.wscotorth.org.uk
PERTHES' DISEASE - Yorkhill.wscotorth.org.uk
PERTHES' DISEASE - Yorkhill.wscotorth.org.uk
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PERTHES’ <strong>DISEASE</strong><br />
DAVID SHERLOCK<br />
Royal Hospital for Sick Children<br />
GLASGOW
HISTORY<br />
1909 - Waldenstrom - Sweden<br />
(but thought it was TB)<br />
1910 - Legg USA<br />
- Calve France<br />
- Perthes Germany
Incidence<br />
Wide geographical variation<br />
• 1:1200 in Masschusetts<br />
• 1:5000 in South Wales<br />
• 1:6000 in Scotland<br />
• 1:12500 in England<br />
80% between ages 4 and 9 (range 2-13yrs)<br />
Male to Female 4: 1<br />
10% bilateral
AETIOLOGY<br />
UNKNOWN - no clear genetic cause<br />
CONSTITUTIONAL FACTORS<br />
short stature, average weight, delayed bone age<br />
ENVIRONMENTAL FACTORS<br />
low birth weight, breech presentation, older<br />
parents, poverty<br />
ASSOCIATED ANOMALIES<br />
hernia, undescended testes, renal anomalies,<br />
pyloric stenosis, congenital heart disease
OTHER THEORIES<br />
• Association of Antithrombotic Factor<br />
Deficiencies and Hypofibrinolysis with<br />
Legg-Perthes’ Disease.<br />
Glueck et al JBJS(1996)78A 3-13<br />
• Not confirmed in other centres including<br />
Glasgow<br />
Jobanputra et al. Brit Soc Haem (2000)44 80
MY THEORY<br />
• GENETIC<br />
- delayed bone age<br />
• CONSTITUTIONAL<br />
- high pain threshold<br />
- hyperactive or overweight child<br />
Extent of each component may vary<br />
between children
PATHOLOGY<br />
• Infarction of capital femoral epiphysis,<br />
partial or total<br />
• Infarction is often sequential<br />
• Repair occurs by creeping substitution with<br />
removal of necrotic bone and its<br />
replacement with new bone or fibrocartilage<br />
• Cartilage nourished by synovial fluid so still<br />
lives, but deforms as bone collapses
PROCESS OF DEFORMITY<br />
The head changes from a sphere to oval as a<br />
result of collapse and lateral overgrowth.<br />
Secondary acetabular remodeling occurs<br />
but the acetabulum remains dysplastic.<br />
This converts the ball & socket to a roller<br />
bearing joint with its movement axis from<br />
extension/adduction to flexion/abduction.
PROGNOSTIC INDICATORS<br />
WHY DO WE NEED THEM?<br />
• Avoids over-treating children who will<br />
do well whatever or who are too late<br />
for treatment to alter the outcome<br />
• Avoids under-treating those who may<br />
get benefit
PROGNOSTIC INDICATORS<br />
• Age<br />
• Extent of head involvement<br />
• (Sex)<br />
• Phase of the disease<br />
• Lateral subluxation<br />
• Physeal growth disturbance<br />
• Metaphyseal changes<br />
• Stiff hip<br />
• Obese child
AGE<br />
In younger children<br />
• Physeal damage occurs less<br />
frequently<br />
• Longer period for remodelling
EXTENT OF INVOLVEMENT<br />
• Catteral classification<br />
• Salter/Thomson classification<br />
• Herring classification<br />
• Arthrographic assessment of<br />
sphericity (Macnicol)
CATTERALL<br />
CLASSIFICATION<br />
• Initial description very complicated. Easiest<br />
to consider as 1/2 head<br />
involvement<br />
• Initial changes seen anterior -> posterior<br />
• Considerable inter- & intra-observer<br />
variability for critical Gp 2/3 divide<br />
• By time class is clear it may be too late to<br />
alter outcome
CATTERAL GROUP 1
CATTERALL GROUP2
CATTERALL GROUP 3
CATTERALL GROUP 4
SALTER-THOMSON<br />
CLASSIFICATION<br />
Assess on AP & Frog lateral X-rays<br />
A: Subchondral fracture of< half head<br />
B: Subchondral fracture of> half head<br />
BUT subchondral fracture only visible<br />
in 15% of cases
SALTER-THOMSON<br />
Subchondral Fracture
HERRING CLASSIFICATION<br />
Assess height of lateral pillar on AP X-<br />
ray in fragmentation phase<br />
A: Normal lateral pillar<br />
B: Pillar height 50-100%<br />
C: Pillar height less than 50%
ARTHROGRAPHIC GRADING<br />
Ismail & Macnicol JBJS 80B, 1998<br />
• Spherical<br />
- no loss of contour in 4 views<br />
• Mild Deformity<br />
- loss in 1 view<br />
• Moderate Deformity - loss in 2 views<br />
• Severe Deformity<br />
- loss in 3 or 4 views
ARTHROGRAPHIC GRADING
SEX<br />
• Females seem to get more serious<br />
form of Perthes’ Disease<br />
• Females may have less time to<br />
remodel since growth finishes<br />
earlier
PHASE AT DIAGNOSIS<br />
• Starting treatment before onset of deformity<br />
maximizes chance of good outcome<br />
• Deformity once present cannot be reversed<br />
• Maintain treatment till head strong enough<br />
to resist loads ie. in healing phase
PHASE OF ONSET<br />
Infarction causes a growth arrest of<br />
the bony epiphysis but the<br />
articular cartilage continues to<br />
grow. This gives the appearance of<br />
widening of the infero-medial joint<br />
space
PHASE OF SCLEROSIS<br />
The femoral head becomes more dense<br />
due to trabecular fracture, appositional<br />
new bone formation and calcification<br />
of the necrotic bone marrow<br />
Disuse osteoporosis in the adjacent live<br />
bone heightens the sclerotic<br />
appearance
PHASE OF SCLEROSIS
FRAGMENTATION PHASE<br />
Repair by creeping substitution causes<br />
the appearance of fragmentation on X-<br />
ray<br />
Repair in thickened articular cartilage<br />
occurs by endochondral ossification: in<br />
the antero-lateral cartilage this gives<br />
the “calcification lateral to the<br />
epiphysis” sign of the “head at risk”
FRAGMENTATION PHASE
PHASE OF HEALING<br />
Necrotic bone is now largely<br />
replaced by new bone but the<br />
femoral head is deformed with<br />
widening of the femoral neck<br />
(Coxa Magna) and flattening of the<br />
head (Coxa Plana)
PHASE OF HEALING
DEFINITIVE PHASE<br />
With healing complete the final<br />
position is now clear<br />
A poor result will show Coxa<br />
Magna and Plana with lateral<br />
subluxation and overgrowth of the<br />
trochanter
SIGNS OF HEAD AT RISK<br />
• CLINICAL<br />
Stiff hip, Obesity, Adduction contracture<br />
• RADIOLOGICAL<br />
Gage’s sign, calcification lateral to the<br />
epiphysis, lateral subluxation, diffuse<br />
metaphyseal changes
SIGNS OF HEAD AT RISK
PROGNOSIS<br />
• 85% develop OA by age 65<br />
• Most do not develop symptoms till 40’s<br />
• 1/3 improve after healing<br />
• 9% get worse requiring THR by age 35<br />
These children often have late onset Perthes<br />
resulting in an irregular uncovered head<br />
with partial growth arrest and a stiff hip
DIFFERENTIAL DIAGNOSIS<br />
UNILATERAL<br />
• Infection<br />
• Gaucher’s Disease<br />
• Haemophilia<br />
• Eosinophilic<br />
Granuloma<br />
• Lymphoma<br />
BILATERAL<br />
• MED<br />
• SED<br />
• Hypothyroidism
TREATMENT PRINCIPLES<br />
• Don’t over-treat children who will do well<br />
anyway<br />
• Restore Movement<br />
• Relieve Stress in Femoral Head<br />
• Contain Femoral Head<br />
• Prevent further Ischaemia
TREATMENT<br />
Hip Abduction reduces forces through<br />
the hip, restores lost movement and repositions<br />
the uncovered antero-lateral<br />
part of the femoral head within the remodelling<br />
influence of the acetabulum<br />
ie. Containment
TREATMENT OF EARLY<br />
PHASES<br />
• Diagnosis, Assessment, Arthrography<br />
• Containment & Mobilization of Hip<br />
• Maintain Containment & Movement<br />
till Healing is established
Maintain containment till healing<br />
established<br />
• Conservative- Retain POP 1-2 years<br />
• Operative<br />
- Age8 Shelf procedure
WHAT I DO<br />
• Age8 Arthrogram, Staheli Shelf
Arthrogram showing minor<br />
deformity
Adjustable Abduction Bar
Varus Osteotomy
Shelf Procedure
FINAL OUTCOME<br />
Stulberg Classification 1981<br />
1 Normal<br />
2 Spherical with Coxa Magna or neck change<br />
3 Non-spherical head with acetabular changes<br />
4 Flat head but congruent with acetabulum<br />
5 Flat head non congruent with acetabulum
Outcome for Perthes in children<br />
under 8 at presentation<br />
• 14 pairs of patients (28 hips) matched for<br />
sex, body mass index, age & phase of<br />
disease at onset degree of head involvement<br />
and at risk signs were abstracted from 345<br />
children with Perthes on our database.<br />
• 5 radiological outcome measures (Mose,<br />
Stulberg, acetabulum-head index,<br />
acetabular roof slope & articulotrochanteric<br />
distance.
Methods<br />
• Radiological outcomes compared for<br />
POP versus surgical treatments<br />
• Surgery comprised varus osteotomy<br />
(8), shelf procedure (5) & Salter<br />
osteotomy (1)<br />
• POP for 7 to 19 months
Results<br />
• 9 Catterall III, 5 IV; 5 Herring B, 9 C.<br />
• All had initial subluxation<br />
• 12 male pairs; 2 female pairs<br />
• No difference in outcome for Stulberg, AHI<br />
& ATD<br />
• Mose 1 grade better for surgery versus POP<br />
• AHI better for shelf procedure but not for<br />
varus osteotomy/ Salter versus POP
Conclusion<br />
• Only difference in outcome for POP versus<br />
surgery treatment was for Mose by 1 grade<br />
(unclear if applies to all surgery or shelf<br />
only) – see after<br />
• Applies to severe Perthes with > half head<br />
involvement & subluxation<br />
• Fits with Herring who found outcome in<br />
Outcome for Perthes in<br />
children over 8 at presentation<br />
Four treatment groups<br />
• No treatment (presented too late)<br />
• Abduction POP till evidence of healing<br />
• Varus osteotomy<br />
• Shelf procedure
Methods<br />
• 44 children (48 hips)<br />
• Followed to maturity in cohort study<br />
• Catterall grades II, III, IV<br />
• Groups demographically similar<br />
• Outcomes assessed by Stulberg, Mose,<br />
% head cover & CEA.
Results<br />
• Over all groups 60% Stulberg 1 to 3<br />
• Poorer outcome (Stulberg, Reimers, CEA)<br />
with increasing age, greater initial head<br />
deformity & more head involvement.<br />
• Initial head deformity did not remodel for<br />
any group<br />
• Deformity increased in POP & varus<br />
osteotomy groups. Static for shelf group.
Conclusion<br />
• Shelf procedure gave better<br />
outcome for Stulberg, Reimer’s<br />
index, CEA & head deformity<br />
than observation or treatment<br />
by POP or varus osteotomy
TREATMENT OF LATE<br />
PRESENTATION<br />
If an Arthrogram shows HINGE<br />
ABDUCTION then a VALGUS<br />
OSTEOTOMY will relieve the<br />
pain of impingement and reduce<br />
leg shortening
Valgus Osteotomy
Profile of Perthes’ in Glasgow<br />
• Burwell et al (1978) suggested link between<br />
Perthes’ & other congenital anomalies<br />
• Barker et al (1983) suggested that poverty<br />
was linked to Perthes’<br />
• Harper et al (1976) found only a minor<br />
genetic component in Perthes’
RHSC PERTHES’ DATABASE<br />
1990-2003<br />
• Total number Perthes’ patients 422<br />
• DAS Perthes’ patients 246<br />
• Demographic details collected for these<br />
patients
GENDER
LATERALITY
MEAN AGE AT DIAGNOSIS 5.9 YEARS<br />
Range 2-12.5. 43%
THANK YOU