Legg-Calve-Perthes disease is a childhood condition caused by avascular necrosis of the femoral head. It leads to deformity of the femoral head and premature osteoarthritis. The exact cause is unknown but it is likely multifactorial, involving both genetic and environmental factors. Treatment depends on the age of the patient, extent of involvement, disease stage, and presence of head deformity. Younger patients often do well with non-operative treatment focusing on range of motion exercises, while older patients or those with more severe deformity may require surgical containment procedures like osteotomies to reshape the femoral head and acetabulum.

1. Legg – Calve – Perthes
Disease
Dr. Ahmed Azim
2nd year resident
TUTH

2. • Disease of children caused by idiopathic ischemic necrosis of femoral
capital epiphysis which may vary in degree and severity
• Following avascular necrosis reossification always occurs
• Leads to permanent femoral head deformity and premature
osteoarthritis

3. Legg – Calve - Perthes
Arthur T. Legg
1874-1939
Jacques Calve
1875-1954
Georg C. Perthes
1869-1927
Henning Waldenstrom

4. Even after 100 years
•Perthes disease remains an enigma shrouded in
controversy

5. Good news!!
• Half the patients will recover and have little disability over their
lifetime
• The other half will function well with occasional discomfort through
most of their adulthood and in their 5th or 6th decade of life require
hip replacement
• Only the most severely involved patients will have early hip disability
Herring JA 1996; Weinstein SL, 1985

6. Applied anatomy
• Blood supply of head
• Upto age 4 mo
1. Metaphyseal vessels penetrate physis
2. Lateral epiphyseal retinacular vessels
3. Scanty vessels in ligamentum teres

7. • Metaphyseal supply gradually
decrease (disappears by 4 yrs)
• Vessels of ligamentum teres
developed by 7 yrs
• 4 yrs – 7yrs blood supply depend
entirely on lateral epiphyseal
vessels

8. Epidemiology
• Incidence: 1 : 10,000
• Usual Age: 4 – 10 yrs
• Male:Female = 4:1
• Billateral in 10-15%
• May be part of general growth disorder
• Higher incidence in underprivileged (UK epidemiologic study)

9. Etiology
• Exact cause unknown
• Affected children: small & delayed maturation
Various theories proposed
• Trauma
• An inflammatory process
• Vascular occlusion
• Thrombophilia
• Insulin-like growth factor-1 pathway abnormality
• Maternal smoking & second-hand smoke exposure
• Type-II collagen mutation

10. Etiology
Prevailing Opinion Is That Legg-calvé-perthes
Disease Is A Multifactorial Disease With Genetic
And Environmental Factors Playing A Role

11. Etiology
Associated features
• Low birth weight
• Breech delivery
• Short stature
• Irritable hip
• Disproportionate growth
• ADHD
• Older parents
• Parents often relate to a trauma
• Genetic predisposition
• Coagulation disorders

12. Pathology
• Disruption of blood supply to the femoral head, is one of the key
pathogenic event
1. Microtrauma to retinacular vessels
2. Increased synovial pressure
eg: Transient synovitis
3. Venous HTN 2⁰ to thrombotic occlusion
• Single ischemic episode vs. multiple ischemic events

13. Pathogenesis & pathology
• Repeated bouts of ischaemia & infarction of femoral head →
pathologic fractures
• Retinacula vessels susceptible to stretching & pressure from effusion
• Increased pressure cause venous stasis
• Increase in intraosseous pressure
• Ischaemia & infarction leading to necrosis

14. Pathogenesis of femoral head deformity
• Pathogenesis of the femoral head deformity following ischemic necrosis is
complex
• Multiple factors contribute to the development of the deformity
1. Mechanical properties of the articular cartilage and the bone are
decreased
• Necrosis of the deep layer of the articular cartilage
• Inability of the necrotic bone to repair microdamage
• Increase in the calcium content of the calcified cartilage and the
subchondral bone making it brittle
• When mechanical loading > strength of bone = subchondral fractures &
collapse

15. Pathogenesis of femoral head deformity
2. Pathological repair process
• Predominance of osteoclastic resorption
• Delayed bone formation
• replacement of the necrotic bone by a fibrovascular granulation tissue
3. Growth arrest of the spherical growth plate
• Restoration of growth in asymmetrical manner

16. Pathogenesis & pathology

17. A flowchart depicting the pathogenesis of the femoral head deformity in Legg-Calvé-Perthes disease.
Harry K.W. Kim J Bone Joint Surg Am 2012;94:659-669

18. Clinical features
• Typically a boy of 4-8 years who has high physical activity
• Smaller than his counterparts
• C/O pain & limping
• Maybe painless limp
• Pain may radiate to knee
• Aggravated by strenuous activity & relieved by rest
• Continuous for weeks or intermittent
• Urogenital anomaly in 4%

19. Clinical features
• Leg length discrepancy
• Mild muscle wasting
• ROM
• Early: joint irritable, decreased ROM & painful in extremes
• Later: Movements full except abduction & IR
• Maybe flexion / adduction contracture
• Gait: Antaalgic or Trendelenburg / Abductor gait
• Trendelenburg test: +ve

20. Diagnosis
• Based on clinical features & Radiology
• Investigations:
• Routine blood investigation
• X-ray
• Initially normal
• Subtle changes: widening of joint space, asymmetry
of ossific centres
• Necrotic phase: Increased density of ossific nucleus
• Fragmentation phase: Alternating patches of
density & lucency
• Crescent sign (best seen on lateral view)
• Re-ossification phase: Increased epiphyseal density

21. Diagnosis
• MRI:
• Evidence of marrow necrosis
• Irregularity of the femoral head,
• Loss of the signal on the affected
side

22. Diagnosis
• Bone scan:
• reduced uptake early in the disease
• Ultrasound
• Joint effusion
• Arthrography: To see congruity, head deformity

23. Classification: Waldenstrom
Stage 1: Initial
phase
• All or part of nucleus dead. Maybe normal X-ray. Increased density of
epiphysis,
• Cartilage thickening, subtle lateral subluxation via increased medial
cartilage growth (Waldenstrom’s sign)
• Subcondral # (Crescent sign)
• Duration: 6 months
Stage 2:
Fragmentation
phase
• Areas of lucency and sclerosis
• Central area separates from lateral & medial areas
• Maximal flattening/collapse
• Duration: 8 months
Stage 3:
Reossification
phase
• New subchondral bone formation
• Flattening may improve
• Duration: 3-5 years
Stage 4: Residual
phase
• No change in bone density
• Shape of head changes
• Final shape after skeletal maturity
• Acetabular remodelling

24. Classification: Modified Waldenstrom

25. Classification: Modified Waldenstrom

26. Classification
• Catterall classification (1982)
• Group I: Normal height of epiphysis & <50%of head
involved
• Group II: ½ of neucleus sclerotic & collapse of central
portion
• Group III: Most of the neucleus involved, fragmentation &
collapse. Metaphyseal resorption maybe present
• Group IV: Whole head, Ossific neucleus is flat & dense,
marked metaphyseal resorption

27. Classification
• Catterall classification (1982)
• Head at risk signs:
1. Lateral subluxation
2. Speckled calcification lateral to the
capital epiphysis
3. Diffuse metaphyseal reaction
(metaphyseal cysts)
4. A horizontal physis
5. The gage sign, a radiolucent v-shaped
defect in the lateral epiphysis and
adjacent metaphysis

28. Classification
• Herring classification
• Greater predictive
value of outcome
• Based on height of
lateral pillar

29. Classification
• Herring classification
• LCPD study group Herring, Kim & Browne
JBJS 2004;86:2121-2134
• 28 institutions: uniform method of treatment
• 345 hips all over age of 6
• Followed till maturity

30. Classification
• Herring classification
• LCPD study group Herring, Kim & Browne
JBJS 2004;86:2121-2134
• Herring A: All do well without any treatment
• Herring B: Bone age <8 : Uniform outcome irrespective treatment
• Herring B: Bone age>8: Surgery (Femoral/Salter) > Brace > No treatment
• Herring C: Bone age<8: Surgery (Femoral/Salter) > Brace > No treatment
• Herring C: Bone age>8: Poor outcome irrespective of treatment

31. Classification
• Salter-Thompson Classification
• Group A: Subchondral # involving
<50 % of head
• Group B: Subchondral # involving
>50 % of head
• Applicable before fragmentation

32. Classification: Stulberg criteria for prognosis
Clas
s
Description Features Prognosis
I Spherical congruency Normal hip joint Good
II Spherical congruency;
Less than 2mm loss of
head shape
Spherical femoral head with 1 more of:
• Coxa magna
• Coxa breva
• Steep acetabulum
Good
III Aspherical congruency;
Greater than 2mm loss
of head shape
Ovoid, mushroom-shaped with 1 or more of
• Coxa magna
• Coxa breva
• Steep acetabulum
Mild-moderate arthritis
IV Aspherical congruency Flat femoral head, abnormal neck and
acetabulum
Mild-moderate arthritis
V Aspherical
incongruency
Flat femoral head with normal shaped neck &
acetabulum
Severe arthritis

33. Classification: Stulberg criteria for prognosis
I
II
III
IV V

34. Poor Prognostic features
• Age over 10 years
• Female Sex
• Degree of head involvement (Caterall & Thompson)
• 2+ Head at risk signs
• Herring C at fragmentation stage
• Premature physeal closure
• Restricted ROM
• Increased weight

35. Differential diagnosis
Practice of pediatric orthopedics
Lynn Stahelli

36. Management:

37. Management
• Principles:
1. Restore & maintain ROM
• Increases joint nutrition
• Prevents subluxation
• Allow abduction
• Satisfactory = 30⁰ ABD
2. Avoid treatment of patients who will do well without treatment
3. Concept of containment
4. Relief of symptoms

38. Management
• Objective: preserve the sphericity of the femoral head
• reduce the risk of stiffness and degenerative arthritis
• preserving the emotional well-being of the child.
• Determined by
• Age
• Extent of involvement
• Stage of disease
• Head at risk signs

39. Management: Age
• The older the child the poorer the outcome
• Role of “biological plasticity”
• Extremely poor outcome in adolescents

40. Management: Age
• Age < 5-6 years
• 50% - 70% do well without treatment
• Little evidence that treatment alters outcome
• Symptomatic treatment to regain ROM
• Regular follow-up
• Consider containment for persistent loss of ABDUCTION

41. Management:
• Concept of containment
• Harrison & Menon stated; “ if the head is
contained within the acetabular cup, then
like jelly poured into a mold the head
should be the same shape as the cup when
it is allowed to come out after
reconstitution”

42. Management:
• Methods of containment
Non-operative
• Braces & casts
Operative
• Femoral osteotomy
• Innominate osteotomy
• Shelf procedure
• Combination of femoral &
innominate osteotomy
• Tripple pelvic osteotomy

43. Management:Non-operative
• >60% do not require surgery
• Observation, activity restriction, traction
& physiotherapy
• Indications:
• <6 years age
• Herring A
• Bracing / Casting
1. Petrie cast
2. Scottish Rite brace

44. Management
• Bed rest with skin traction until the synovitis
subsides (4 to 14 days)
• Children 2 to 3 years old can be observed and do
not need aggressive treatment.

45. Management
• If significant loss of motion & lateral
subluxation:
• Closed reduction + adductor tenotomy
• Petrie cast
• Satisfactory clinical results can be obtained at
long-term follow-up despite an unsatisfactory
radiographic appearance (Cambell’s operative
orthopedics)

46. Management: Containment Surgery
• Timing of surgery: More important than the type of surgery
• Should be done before irreversible deformation of the femoral head
occurs

47. Management
• Inominate osteotomy
• Advantages:
• anterolateral coverage of the femoral head,
• lengthening of the extremity
• avoidance of a second operation for plate removal
• Disadvantages:
• Inability to obtain proper containment
• Increased acetabular & joint pressure
• Increase leg length causing relative adduction

48. Management
• Inominate osteotomy
Innominate osteotomy using quadrangular
Graft (Canale et al)
Salter innominate osteotomy

49. Management
• Lateral Shelf procedure
• Indicated in older children in later stages
• Not candidates for femoral osteotomy
• Insufficient remodeling capacity
• Shortening of limb would cause persistent limp
• Recently indicated in early active stages
1. Lateral acetabular growth stimulation
2. Prevention of subluxation
3. Shelf resolution after femoral epiphyseal
reossification

50. Management
• Lateral Shelf procedure

51. Management
• Varus derotational osteotomy
• Advaantages
• Seats the head deeply in acetabulum
• Removes vulnerable ant/lat portion from acetabular
edge
• Decrease joint reaction forces
• Disadvantages
• excessive varus angulation (especially in an older child)
• Limb shortening
• Trendelenburg gait
• Nonunion
• Hardware removal
• Premature closure of the capital femoral physis may
cause further varus deformity & trachantric overgrowth

52. Management

53. Management
Arthrodiastasis
• Distraction of joint
• Widens joint space
• Unloading of joint
• Allows fibrous repair of cartilage defects
• Preserves congruency
• Articulated fixator allows 50⁰ flexion

54. Management: Residual deformities &
complications
Hinge
abduction
Coxa breva
Trochanteric
overgrowth
Coxa
irregularis
FAI Early OA

55. Management
Reconstructive surgeries and salvage
procedures
• Valgus osteotomy
• Cheilectomy
• Shelf procedure
• Chiari osteotomy
• Trochanteric advancement

56. Management
Reconstructive surgeries and salvage
procedures
• Valgus osteotomy
• Cheilectomy
• Shelf procedure
• Chiari osteotomy
• Trochanteric advancement

57. Management
Reconstructive surgeries and salvage
procedures
• Valgus osteotomy
• Cheilectomy
• Shelf procedure
• Chiari osteotomy
• Trochanteric advancement

58. Management
Reconstructive surgeries and salvage
procedures
• Valgus osteotomy
• Cheilectomy
• Shelf procedure
• Chiari osteotomy
• Trochanteric advancement

59. Management
Reconstructive surgeries and salvage
procedures
• Valgus osteotomy
• Cheilectomy
• Shelf procedure
• Chiari osteotomy
• Trochanteric advancement

60. Management
Newer strategies
• Anti-resorptive therapy
• RANKL inhibitor – Denosumab (inhibits osteoclast formation)
• Bisphosphonates (Decrease osteoclast activity)
• Bone anabolic therapy to stimulate new bone formation
• Effects of BMP administration on bone formation in the
context of femoral head osteonecrosis are being investigated
• Intraosseous administration of bisphosphonates

61. Conclusion
• A disease surrounded by various unknown factors and several controversies
• Etiology remains unclear – multiple theories – common end point
• Although LCPD cannot be prevented, progress has been made regarding risk stratification
and minimizing its deleterious effects on the hip primarily via operative treatment
• Multiple classification systems exist – non predictive of final outcome in early stages
• No common consensus on treatment plan
• Age & degree of involvement most important
• <6yr : non-operative
• >6yr: containment surgery if Herring B / C
• 8+ yrs: poor outcome regardless of Tx, ; salavage procedures
• Current basic science research efforts and clinical studies hold out the promise of
providing patients with even better long-term results in the future.

62. THANK YOU
• Next presentation: Slipped capital femoral epiphysis
• Dr. Sirish Adhikari

63. References
• Campbell’s Operative Orthopedics 12th ed
• Practice of paediatric orthopedics 2nd ed (Lynn Stahelli)
• Apley’s system of orthopedics 9th ed
• Tachdjian’s pediatric orthopedics
• Pathophysiology and New Strategies for the Treatment of Legg-Calvé-
Perthes Disease
Harry K.W. Kim, MD, MS, FRCSC ; J Bone Joint Surg Am, 2012 Apr 04; 94 (7): 659 -669 .
• Legg-Calve-Perthes Disease: Where Are We 100 Years Later? Charles T. Mehlman,
D.O., M.P.H., FAOAO, Professor of Pediatric Orthopaedic Surgery; Jessica Blair McCourt, M.P.A.S, PA-C, Pediatric
Orthopaedic Physician’s Assistant, Cincinnati Children’s Hospital Medical Center, University of Cincinnati
College of Medicine, Cincinnati, Ohio