UMEM Educational Pearls

Category: Orthopedics

Title: Knee Injuries

Keywords: knee, injury, dislocation (PubMed Search)

Posted: 6/21/2014 by Michael Bond, MD (Updated: 3/29/2024)
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Some quick facts about Knee Injuries:

  • The most common cause of acute traumatic hemarthrosis of the knee is an anterior cruciate ligament tear.
    • Most patients with an ACL injury will give a history of immediate pain, disability, knee swelling and audible pop.
  • The most common ligament injuried in the knee is the medial collateral ligament.
  • Patella dislocations
    • Usually lateral dislocations and often spontaneous reduce.
    • Hyperextend the knee to make the reduction easier.
  • Dislocation of the knee:
    • Anterior is the most common and usually secondary to hyperextension
    • Popliteal artery injury is commonly seen and must be looked for.  Easy bedside test is Ankle Brachial Index.
    • Normal pulses do NOT exclude a vascular injury.
    • Patients should be monitored for vascular complications and compartment syndrome.
    • Vascular injuries due to knee dislocation are associated with a high rate of amputation, which markedly increases if not repaired within 6-8 hours.