I. See Also

II. Epidemiology

  1. Incidence: 20,000/year in United States
  2. Most common in men ages 30-50 years old
  3. Leg-Calve-Perthes Disease is idiopathic osteonecrosis of the femoral head in children ages 2-12 years old

III. Risk Factors (compromise femoral head blood supply further)

  1. Most significant common cases denoted (*)
    1. Pregnancy
    2. Chemoradiation
    3. Sickle Cell Anemia
  2. Hematologic Causes
    1. Coagulopathy
    2. Sickle Cell Disease (*)
  3. Gastrointestinal Causes
    1. Chronic Liver Disease
    2. Chronic Pancreatitis
  4. Rheumatologic Causes
    1. Gout
    2. Systemic Lupus Erythematosus
  5. Medication, substances and exposures
    1. Chemotherapy (*)
    2. Radiation Therapy (*)
    3. Alcohol Abuse
    4. Corticosteroids
  6. Lipid Disorders
    1. Hyperlipidemia
    2. Gaucher Disease
  7. Miscellaneous Causes
    1. Diabetes Mellitus
    2. Pregnancy (*)

IV. Pathophysiology

  1. Femoral head subchondral bone with irreversible anoxia
    1. Results in secondary osteocyte death
    2. Osteoblasts are active in surrounding bone
  2. Subchondral trabeculae fails and result in collapse of Hip Joint space

V. Symptoms

  1. Progressive Groin Pain, gradually increasing over weeks to months
  2. Starts unilaterally (but ultimately bilateral in over 70% of cases)
  3. Radiation into medial thigh
  4. Provoked with weight bearing (especially while standing with all weight on affected leg)
  5. Pain at rest suggests advanced avascular necrosis

VI. Signs

  1. Hip Range of Motion
    1. Normal initially
    2. Later significantly limited active and passive range of motion due to joint destruction and collapse

VII. Diagnosis

  1. Typically delayed diagnosis until advanced stages (due to insidious, gradual presentation)

VIII. Imaging

  1. MRI Hip (preferred)
  2. XRay Hip (first-line, initial study)
    1. Stage 0 and 1: Normal XRay
    2. Stage 2: Hip sclerosis, bone cysts and Osteopenia
    3. Stage 3: Crescent sign
      1. Femoral head flattening of the superior aspect
      2. Subchondral Fracture parallel to articular surface
    4. Stage 4: Femoral head collapse
    5. Stage 5-6: Joint destruction

IX. Management

  1. Orthopedic referral
  2. Hip replacement in nearly all cases

X. Prognosis

  1. Responsible for 12% of all hip replacements in the United States

XI. References

  1. Shahideh (2013) Crit Dec Emerg Med 27(9):10-18

Images: Related links to external sites (from Google)

Ontology: Avascular Necrosis of Femur Head (C0410480)

Concepts Pathologic Function (T046)
MSH D005271
SnomedCT 203476003
English AVASCULAR NECROSIS FEMORAL HEAD, Avascular necrosis, head-femur, Avascular necrosis of femoral head, AVASCULAR NECROSIS OF FEMORAL HEAD, PRIMARY, ISCHEMIC NECROSIS OF FEMORAL HEAD, FEMORAL HEAD, AVASCULAR NECROSIS OF, OSTEONECROSIS OF FEMORAL HEAD, ANFH, FEMORAL HEAD NECROSIS AVASCULAR, Avascular Necrosis of Femur Head, avascular necrosis femoral head, avascular femoral heads necrosis, femoral head avascular necrosis, avascular femoral head necrosis, FEMORAL HEAD, ASCEPTIC NECROSIS OF, Avascular necrosis of the head of femur, Avascular necrosis of the head of femur (disorder), Avascular Necrosis of Femoral Head, Necrosis, Avascular, of Femur Head, Avascular necrosis femoral head
Dutch avasculaire necrose van femurkop, Femurkopnecrose, avasculair, Necrose, avasculair, van femorkop
German aseptische Nekrose des Femurkopfs, Nekrose, avaskuläre, des Femurkopfes, HUEFTKOPFNEKROSE NICHT GEFAESSBED, Avaskuläre Nekrose des Femurkopfes
Italian Necrosi avascolare della testa femorale
Portuguese Necrose avascular da cabeça femural, NECROSE AVASCULAR DA CABECA DO FE, Necrose Avascular da Cabeça do Fêmur
Spanish Necrosis avascular de la cabeza del fémur, Necrosis Avascular de la Cabeza Femoral, NECROSIS AVASCULAR CABEZA FEMUR, Necrosis Avascular de la Cabeza del Femur, Necrosis Avascular de la Cabeza del Fémur, necrosis avascular de la cabeza del fémur (trastorno), necrosis avascular de la cabeza del fémur
Japanese 大腿骨頭無腐性壊死, ダイタイコットウムフセイエシ, ダイタイコツトウムフセイエシ
French Nécrose avasculaire de la tête fémorale, NECROSE DE LA TETE FEMORALE, Ostéonécrose avasculaire de la tête du fémur, Ostéonécrose avasculaire de la tête fémorale, Nécrose avasculaire de la tête du fémur
Czech Avaskulární nekróza hlavičky femuru
Hungarian Avascularis necrosis a femur fejben