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Case of the Week 330

What's the most likely diagnosis?

  • 41 year-old male with severe knee pain

  1. Blount's disease
  2. Patellectomy
  3. Fong's disease
  4. Dislocated knee
  5. Fibular fracture

Additional Images - Frontal view of knee


Additional Images

Frontal view of the same knee


4. Dislocated knee

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Dislocation of the Knee

General Considerations

  • Uncommon dislocation
  • Most are either anterior or posterior
  • Using the position of the tibia as the reference
    • Anterior dislocations (most frequent)
      • Hyperextension
      • Posterior dislocations (second most frequent)
        • Force to anterior tibia with knee flexed as in MVC or falls
      • Medial, lateral or rotational
        • Valgus, varus or rotational forces
      • As many as 50% of knee dislocations spontaneously self-reduce
    • Can lead to underestimation of damage


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This Week

41 year-old male with severe knee pain

Compression, burst, Chance, transverse process fractures and traumatic spondylosis are reviewed in this video podcast that complements Video Podcast 11-Cervical Spine Trauma.


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