blounts disease

1. Blounts Disease
By Dr Harsimranjeet Singh Sidhu
Chairperson- Dr Rupa Kumar C.S

2. History
• Erlacher was the first to describe tibia vara and
internal tibial torsion- 1922.
• Blount- 1937- His Article prompted the diagnosis of
this disorder
• Langenskiold in 1952 came up with classification for
this disorder

3. Dr Blount Description
• “an osteocondrosis similar to Coxa Plana
and Madelung deformity but located at
the medial side of the proximal tibial
epiphysis”

4. Introduction
• It is a developmental condition
characterised by a disturbance of
orderly sequence of enchondral
ossification at the upper end of the
tibia, affecting the medial portion of
growth plate, mainly in its
posteromedial aspect and medial
portion of the epiphyseal ossification
centre.
• Resulting in abrupt varus
angulation at proximal portion oF
tibial metaphysis , while diaphysis
remains straight.

5. Etiology- What Causes It.
• Current concept – tibia vara is an acquired
disease of proximal tibial metaphysis of
unknown cause.
• Enchondral ossification is most likely altered.

6. Suggested causative factors
• Infection
• Trauma
• Osteonecrosis
• Latent form of rickets
ALTHOUGH NONE HAVE BEEN PROVED
Combination of developmental and hereditary
factors is most likely the cause

7. • The Relationship of early walking and obesity
with Blount disease has been clearly
documented.
• Rarely seen in non ambulatory children.

8. ETIOLOGY contd
• Familial occurance reported by several
authors…..but as noted by Langenskiold and
Riska, because radiographic features of infantile
tibia vara have never been seen in patients
younger than 1 year and rarely before 2
years..this condition should be consider
congenital one.

9. PATHOLOGY
Histologic evaluation of affected growth plates and
corresponding part of metaphysis shows :-
1. Islands of densely packed cartilage cells
displaying greater hypertrophy than expected
from their position in growth plate.
2. Island of nearly acellular cartilage.
3. exceptionally large clusters of capillary
vessels.

10. Pathophysiology
• The physeal cell collumns become irregular
and disordered in arrangement and normal
endochondral ossification is disrupted , both in
the medial aspect of metaphysis and in
corresponding part of physis.
• Varus deformity progresses as long as
ossification is defective and growth continues
laterally on lateral part of physis.

11. • In later stages , an actual bony bridge may
tether the medial growth , and the medial tibial
plateau may apear deficient posteromedialy.
• Ligamentous laxity on lateral side of knee
frequently develops in a neglected or recurrent
deformity .

12. Classification
• Blount distinguished it as :-
Infantile-
Less than 8 years of age
bilateral in 60 %
Adolescent :-
more than 8 years to skeletal fusion.
with a cause- black, obese.

13. Langenskoild classification (1952)
Depending on degree of
metaphysial epiphysial changes-
6 progressive stages with
increasing age
• Stage I- Irregular metaphyseal
ossification combined with
medial and distal protrusion of
the metaphysis.
• Stage II,III, IV - evolves from
mild depression of the medial
metaphysis to a step- off of the
medial metaphysis.

14. Langenskoild classification (1952)
Stage V- Increased slope of medial articular
surface and a cleft separating the medial and
lateral epicondyle.
• Stage VI- Bony Bridge across the physis.

15. • Bowleg deformity first
becomes apparent when
infant starts to stand and walk.
• Obese child.
• DEFORMITY
 Sharp medial angulation of
tibia at metaphysis.
Deformity more evident in
weight bearing position
Internal tibial torsion

16. Clinical Picture

17. • To compensate for the tibial varus , the medial
femoral condyle hypertrophies.
• Over the medial aspect of epiphyseometaphyseal
junction , a bony , hard , non tender prominence is
palpable( reffered as BEAK on xrays )
• In long standing neglected cases –
 slight flexion deformity is added to varus deformity.
 collateral ligaments become lax- joint unstable.
 medial tibial condyle becomes severely depressed
and OA develops within medial compartment of
knee.

18. Radiological examination
• Standing AP view from hip to ankle.
FEATURES :-
 Varus angulation at the epiphyseal
metaphyseal junction.
 Widened and irregular physeal line
medially.
 Medially sloped and irregular ossified
epiphysis, sometimes triangular.
 Prominent beaking of the medial
metaphysis with lucent cartilage
islands within the beak.
 Lateral subluxaton of the proximal
end of tibia.

19. Metaphyseal Beak

20. Tibia Femoral Angle
• Normally progresses from
pronounced varus before age
of 1 year to valgus between
the ages 1.5 to 3 years…
• any deviation from normal
tibiofemoral angle
development indicates Blounts
disease.

21. Metaphysio diaphyseal Angle
• Levin And Drennan
• If angle > 11 degree- mostly
blount lesions
• If angle < or = 11
degree….mostly resolves.

22. Further Work Up
• No specific blood markers.
• TESTS to rule out Rickets, ViTamin D deficiency
• Ct scan is indicated to detect physeal bar in
children above 5 years of age.

23. Diffrential Diagnosis
• Physiologic Genu Varum
• Skeletal dysplasias
• Metabolic diseases ( renal osteodystrophy, vit d
resistant rickets )
• post traumatic deformity
• Post infective sequelae

24. Developmental (physiological) bowing:
Developmental bowing Blount disease
Disappear after 2 years. Progressive.
Bilateral and symmetric. Unilateral or bilateral
asymmetric.
Metaphyseal diaphyseal
angle < 11
Metaphyseal diaphyseal
angle > 11

25. TREATMENT
• Treatment choices and prognosis greatly depends
upon on the age of the patient and radiographic
stage of the disease

26. ORTHOTICS
• INDICATIONS
Child younger than 3 years of age
Lesions not greater than langenskiold stage 1 and 2.
Especially if unilateral involvement.

27. KNEE ANKLE FOOT ORTHOSIS(KAFO)
• Rainley.et all Prefferred LOCKED
KAFO that produced valgus force
by 3 points pressure.
• Recommended 23 hrs /day.
• Full weight bearing.
RISKS of failure:-
 Ligamentous laxity.
Patient weight above 90
percentile.
Late initiation of bracing.

28. ELASTIC BLOUNT BRACE
• 1987
• A medial upright design
that uses a wide elastic
band just distal to the knee
joint.
• Excusively used
 ease of fabrication
Smaller profile

29. Corrective Osteotomy Options
 METAPHYSEAL
 EPIPHYSEAL- METAPHYSEAL
INTRA EPIPHYSEAL

30. Rx – CORRECTIVE OSTEOTOMY
• In children older than 9 years with more severe
involvement , osteotomy alone , with bony bar
resection , or with epiphysiodesis of lateral tibial
and fibular physis is indicated.
• For older Children in whom bracing and tibial
osteotomy have failed to prevent progressive
deformity , Ingram , Siffert and others have
suggested an intraepiphyseal osteotomy to correct
severe joint instability and a valgus metaphyseal
osteotomy to correct the varus angulation

31. CORRECTIVE OSTEOTOMY Rx
• Schoenecker et al- elevation of medial tibial
plateau along with metaphyseaal wedge osteotomy
• Gregosiewics – Double elevating osteotomies;
intraepiphyseal and metaphyseal.
• Zeyer – hemicondylar tibial osteotomy through the
epiphysis into the tibial intercondylar notch.
• Bell, Coogan- Recommended illizarov technique.

32. Metaphyseal oblique osteotomy
• George .T.Rab
• Advantage-
• single plane oblique cut allows
simultaneous correction of varus and
internal rotation .
• permits postoperative cast wedging if
necessary to obtain appropriate position.

35. • Post-operatively
Cast is changed at 4 weeks
Weight bearing allowed if callus evident over
radiographs
Cast worn till 8 weeks/ till union is evident
radiologically

36. CHEVERON OSTEOTOMY
• GREENE
• MODIFICATION OF DOME OSTEOTOMY
• Advantages
 Greater Stability
 Mininmal changes in leg length.

37. TECHNIQUE
 Fibular osteotomy.
• Tibial osteotomy.
• Osteotomy fixation with
pin.
• Long leg bent knee cast .
• Postoperative

38. DISADVANTAGES
Loss of fixation/ correction
 longer period of cast
immobilisation

39. HEMICONDYLAR OSTEOTOMY
• ZAYER
INDICATED –
LIGAMENTOUS LAXITY
EXTREME DEPRESSION
AND SLOPING OF
MEDIAL TIBIAL
CONDYLE.

40. INTRA EPIPHYSEAL OSTEOTOMY
• Stiffert , Johnson ET AL.
• Indication
severe joint instability
To correct intrarticular
components of Blount
disease
• in addition valgus osteotomy
to correct genu vara.

41. ILIZAROV TECHNIQUE
• Effective in correction of deformity and
lengthening if indicated in adolescent patient.
• Allows – adjustment of limb alignment
postoperatively.
• Fixation to tibia is achieved by 4 proximal and 4
distal wires that are affixed to rings and
tensioned.

42. COMPLICATIONS
• Common peroneal nerve palsy.
• Compartment Syndrome
• Anterior Tibial Artery Occlusion
• Recurrence

43. Treatment in breif
AGE LANGENSKOILD
STAGE
TREATMENT
< 2 YEARS STAGE 1 AND 2 OBSERVATTION
2-3 YEARS STAGE 1 AND 2 MODIFIED LOCKED KAFO
3-8 YEARS STAGE 2 TO
STAGE 3
OBLIQUE / CHEVERON
OSTEOTOMY
9+ YEARS STAGE 4 AND
ABOVE
RESECTION OF BONY/ PHYSEAL
BAR + OSTEOTOMY + EPIPHYSEAL
ELEVATION +/- LATERAL
EPIPHYSEAL EPIPHYSEODESIS

44. REFERENCES
1. Campbells operative orthopaedics volume 2;
12th edition
2. Tachdijian’s pediatric orthopedics volume 2;
4th edition
3. Turek orthopaedic principle and application
volume 2 ;4th edition.

45. THANK YOU!!!!!!!