Knee Dislocations - Dr. Gibbs

Basics

• Can result from high OR low velocity injuries.
• ~30% of high-velocity dislocations have associated life-threatening injuries.
• 60% have associated fractures. 40% have multiple fractures.
• 15-30% have vascular injury!!
  

The Literature is Consistent

• An ABnormal exam mandates angiography!
• A NORMAL exam is associated with either no injury or inconsequential vascular injury.
• An Ankle-Brachial-Index (ABI) < 0.9 is indicative of vascular injury.
• An ABI of > 0.9 is highly predictive of lack of significant vascular injury.

Imaging?

• Duplex Doppler has reported sensitivity of 95%, but is operator dependent and can miss intimal tears.
• CT Angiography is highly sensitive for vascular injury, but do a good exam and check ABIs first!

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