Legg-Calve-Perthes disease is an idiopathic avascular necrosis affecting the capital femoral epiphysis primarily in children aged 5 to 7, with a higher incidence in males and lower socioeconomic groups. The condition progresses through four phases: necrosis, fragmentation, reossification, and remodeling, with various treatment options based on age and severity. Prognosis varies, generally being better for younger patients, although long-term complications such as hip arthritis can occur in some cases.

1. Legg-Calve-Perthes disease

3. • Idiopathic AVN of capital femoral
epiphysis.
• Described independently by Arthur
Legg, Jacques Calve, and Georg
Perthes in 1910.
• Also known as Coxa plana, Legg-
Perthes, Legg Calve, or Perthes
disease.

4. Epidemiology
• Age: Highest rate of occurrence at 5 to 7 years.
• Incidence: 1 in 1200 children under the age of 15.
• Male preponderance (male to female ratio between 4:1 and 5:1).
• Bilateral : 10% to 20% of affected cases. Bilateral cases are usually
asymmetrical, in different stages of the disease. If it is symmetrical, the
examiner must consider multiple epiphyseal dysplasias as the culprit.
• Caucasians and Asians are more commonly affected.
• It is also more prevalent in urban areas in patients with lower socioeconomic
status.

5. Etiology
• Idiopathic
• Disturbed blood flow to femoral epiphysis :
1. Trauma (macro or repetitive microtrauma),
2. Coagulopathy,
3. Steroid use.
Thrombophilia is present in approximately 50% of patients,
and some form of coagulopathy is present in up to 75%

6. Risk factors
• Familial : 10%(there is a delayed bone age by about 2 years)
• HIV (Up to 5% of HIV patients have avascular necrosis of the hip)
• Factor V Leiden and other inherited coagulopathies
• Thrombophilias (increased clotting)
• Hypofibrinolysis (decreased ability to dissolve clots)
• Secondhand smoke exposure (OR=5)
• Low socioeconomic status
• Birth weight less than 2.5 kg in boys
• Short stature

7. Pathophysiology
4 phases:
• Necrosis: Disruption of the blood supply leads to infarction of the
femoral capital epiphysis, particularly the subchondral cortical
bone. Subsequently, this leads to a cessation of the growth of the
ossific nucleus. The infarcted bone softens and dies.
• Fragmentation: Body reabsorbs the infarcted bone.
• Reossification: Osteoblastic activity takes over, and the femoral
epiphysis reestablishes.
• Remodeling: New femoral head may be enlarged or flattened. It
reshapes during growth. Responders to conservative treatment
will usually show healing in 2 to 4 years.

9. History
• Limp of acute or insidious onset, often painless (1 to 3 months)
• Pain localized to hip or referred to the knee, thigh, or abdomen
• Pain typically worsens with activity
• No systemic symptoms should be found
Physical Examination
• Decreased internal rotation and abduction of the hip
• Pain on rotation referred to the anteromedial thigh and/or knee
• Disuse atrophy of thighs and buttocks
• Afebrile
• Leg length discrepancy
Gait Evaluation
• Antalgic gait (acute): Short-stance phase secondary to pain in the weight-bearing
leg
• Trendelenburg gait (chronic): Downward pelvic tilt away from the affected hip
during the swing phase

10. Diagnostic Imaging
Early radiographs can be normal
Plain films are preferred
Standard anteroposterior pelvis and frog-leg
lateral views
Early Findings
•Widening of joint space (epiphyseal
cartilage hypertrophy)
•Changes in epiphysis (smaller, appears
denser)
• Crescent sign:" subchondral radiolucent
zone of anterolateral epiphysis (subchondral
fracture)
Late Findings
•Flattening , fragmentation, healing
(sclerosis) of femoral head

11. LATERAL PILLAR OR HERRING
CLASSIFICATION

12. Waldenström classification
• Refers to x-ray abnormalities and represents four temporal
phases of the disease. These stages have been further subdivided
in modified Elizabethtown classification .
• Stage I: early
– asymmetric femoral epiphyseal size (smaller on the affected
side)
– apparent increased density of the femoral head epiphysis
– widening of the medial joint space
– blurring of the physeal plate
– radiolucency of the proximal metaphysis

13. • Stage II: Fragmentation
– subchondral lucency (crescent sign)
– femoral epiphysis fragments
– femoral head outline is difficult to make out
– mottled density
– thickened trabeculae
• Stage III: Reparative
– re-ossification begins
– shape of the femoral head becomes better defined
– bone density begins to return
• Stage IV: Healed
– depending on the severity, the femoral head may be nearly normal or may
demonstrate:
• flattening of the articular surface, especially superiorly
• widening of the head and neck of the femur

15. Prognostic Factors
Age at Onset
• Usually younger age at diagnosis equals a better outcome.
• Patients less than 6 years old may develop a normal hip joint.
• Patients older than 6 years may have continued pain and subsequent arthritis.
Lateral Pillar Classification (degree of femoral head involvement: A [least] to C
[most])
• Patients more than 8 years old and patients in lateral pillar group B or B/C (border
group) do better with surgery than with nonoperative treatment.
• Patients less than 8 years old and patients in group B do well regardless of treatment
choice.
• Patients in group C experience poor outcomes regarding hip condition, regardless of
treatment choice.
Gender
• Female patients have worse prognoses than male patients if onset occurs at more than
8 years of age.

16. • Overall prognosis for Legg-Perthes is good.
• After the one to two years of treatment, children return to normal
physical activities and sports.
• Most patients will have no symptoms as a teenager.
• Long-term prognosis is also good, although in some cases the
individual may develop hip arthritis at age 50 to 60.
• In rare cases, the hip can become stiff and painful even as a teenager
with a less then desired result.

17. Treatment / Management
Goals :
• Pain and symptom management,
• Restoration of hip range of motion,
• Containment of femoral head in acetabulum.

18. Nonoperative Treatment
Indication: Children with bone age < 6 or lateral pillar A involvement.
• Activity restriction and protective weight-bearing are recommended
until ossification is complete.
• Patient may still take part in physical therapy.
• Literature does not support the use of orthotics, braces, or casts.
• NSAIDs can be prescribed for comfort.
• Good outcomes reported in up to 60% of patients.

19. SCOLTTISH RITE
BRACE

20. OPERATIVE TREATMENT
Femoral or Pelvic Osteotomy
• Indications: children >8 years
• Lateral pillar B and B/C have improved outcomes with surgery compared to A and C
• Studies suggest early surgery before femoral head deformity develops
Valgus or Shelf Osteotomies
• Indications: children with hinge abduction
• Improves abductor mechanism
Hip Arthroscopy
• An emerging modality for treating mechanical symptoms and/or femoroacetabular
impingement.
Hip Arthrodiastasis
• Controversial option

21. FEMORAL
OSTEOTOMY

23. Recovery
• 50% of patients almost fully recover, with no long-term
sequelae.
Pain and Disability
• 50% of patients develop pain and disability in their 40s and
50s and degenerative joint disease leading to hip replacement
in their 60s and 70s.

24. Complications
• Coxa magna: widening of femoral head
• Coxa plana : flattening
• Premature physeal arrest (can lead to leg length discrepancy).
• Acetabular dysplasia and resultant hip incongruency. This can lead to
altered mechanics and subsequent labral tears.
• Lateral hip subluxation or extrusion is a complication associated with
a poor outcome and can lead to lifelong problems for the patient.
• Hip arthritis: Late complication

25. Differential Diagnosis
• Infectious etiology : septic arthritis, osteomyelitis,
pericapsular pyomyositis
• Transient synovitis
• Multiple epiphyseal dysplasia (MED)
• Spondyloepiphyseal dysplasia (SED)
• Sickle cell disease
• Gaucher disease
• Hypothyroidism
• Meyers dysplasia