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Hemophilia

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Topic updated on 05/09/16 3:49pm
Introduction
  • A bleeding disorder that results from
    • Hemophilia A
      • decreased or absent factor VIII
    • Hemophilia B
      • decreased or absent factor IX
  • Epidemiology
    • incidence
      • Hemophilia A
        • approx. 1 in 5000 boys/men
      • Hemophilia B:
        • approx. 1 in 30,000 boys/men
    • location
      • excessive bleeding into joints and muscle
      • hemarthrosis most commonly affects the knee 
      • other joints affected include
        • elbow, ankle, shoulder, and spine
  • Pathophysiology
    • Factors VIII and IX required for the generation of thrombin in the intrinsic coagulation pathway
    • results in unstable clot formation and excessive bleeding
  • Genetics
    • inheritence pattern
      • congential hemophilia
        • X-linked recessive disorder (typically affects males only)
      • aquired hemophila
        • rare condition with autoimmune ethiology, with no genetic inheritence
  • Orthopaedic manifestations
    • hemophilic arthropathy  
      • synovitis
      • cartilage destruction
      • joint deformity
      • pseudotumor 
    • intramuscular hematoma (pseudotumor)
      • may lead to nerve compression
        • iliacus hematoma may compress femoral nerve and presentswith paresthesias in the L4 distribution  
    • leg length discrepancy
      • due to epiphyseal overgrowth
    • fractures
      • due to generalized osteopenia
      • will heal in normal time
    • compartment syndrome
  • Prognosis
    • natural history of diease
      • Disease severity determined by degree of coagulation factor deficiency
        • mild: 5-25%
        • moderate: 1-5%
        • severe: 0-1%
    • prognositc variables
      • treatment related inhibitors (e.g. Immunoglobulin G antibody inhibitors)
        • IgG antibody to clotting factor proteins
        • inhibits response of therapeutic factor replacement
        • present in 4-20% of hemophillia patients and can develop at any time
        • presence is a relative contraindication for surgery
      • blood borne infections
        • high risk of viral transmission
        • prevalence of HIV in hemophiliacs is approx. 10-15%
      • allergic reaction to infused blood products
Presentation
  • History
    • male gender
    • family history of hemophilia, usually maternal uncles
  • Symptoms
    • recurrent or severe bleeding
    • bleeding in unusual places (e.g. joints)
    • mucocutaneous bleeding (e.g. gums, nose, easy bruising)
  • Physical Examination
    • inspection
      • pallor
      • joint effusions
      • bruising 
    • movement
      • joint tenderness
      • decreased ROM
      • focal neurological deficits
      • muscle pain (bleeding most commonly in quadriceps, hamstrings, iliopsoas, biceps, triceps)
Imaging
  • Radiographs
    • recommended views of knee  
      • AP, lateral, oblique and skyline
    • general findings
      • epiphyseal overgrowth
      • generalized osteopenia
      • fractures
      • irregularity of the joint space
      • joint effusion
    • specific findings
      • squaring of patella and femoral condyles (Jordan's sign)
      • ballooning of distal femur
      • widening of intercondylar notch
      • patella appear long and thin on lateral
  • CT scan
    • indication
      • evaluate pseudotumors
      • characterize fracture pattern
    • findings
      • determine the location of pseudotumor in soft-tissue or bone
      • better visualization of fracture pattern and characteristic
      • MRI better than CT at visualizing soft tissue characteristics
  • MRI
    • indication
      • soft tissue evaluation
      • evaluate cartilage
    • findings
      • hemarthrosis, synovitis, and hemosiderin deposition in the joint
      • best visualization modality of soft-tissue anatomy
  • Ultrasound
    • indication
      • differentiate effusion from pseudotumor
      • often helpful to prospectively follow intramuscular hematomas 
Studies
  • Labs:
    • CBC (check Hb levels)
    • aPTT prolonged, PT normal
    • plasma factor VIII or IX inhibitor assay
    • LFTs normal
  • Screening
    • Bethesda assay
      • performed is blood factor VIII or IX inhibitor are positive
      • measures the amount of factor VIII or IX antibody in the blood
      • measurements=no titre, <5 BU (low levels), >5BU (high levels) 
Treatment
  • Nonoperative
    • analgesics, pain team evaluation, physiotherapy, 
      • indications
        • non-life threatening bleeds into joint or muscle
        • adjunct measures
      • modalities
        • codiene in children should be moderated by local prescriber
        • joint immobilization and joint paracentesis are not routinely recommended
    • factor VIII or IX administration 
      • indications
        • relavent factor is administered for Hemophilia A (Factor VIII) and B (Factor IX)
        • estabilished bleed with decreased factor VIII and IX or increased Bethesda assay (>5 BU)
      • modalities
        • increase factor levels by risk of potential blood loss and bleeding
          • acute hematomas
            • increase blood factor levels to 30% 
          • acute hemarthrosis and soft tissue surgery 
            • increase blood factor levels to 40-50%
          • skeletal surgery
            • increase blood factor levels to 100% for first week following surgery then maintain at > 50% for second week following surgery
  • Operative treatment
    • synovectomy and/or contracture release
      • indications
        • may be indicated for recurrent bleeding into a specific joint causing:
          • chronic synovitis
          • recurrent hemarthrosis
      • technique
        • radioactive synoviorthesis (destruction of synovial tissue with intra-articular injection fo radioactive agent)
        • surgical synovectomy
      • outcomes
        • synoviorthesis has been shown to reduce incidence of recurrence greater than surgical synovectomy
    • total joint arthroplasties 
      • indications
        • for end stage arthropathy

 

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