Bone Contusion Pattern

√edema of mid portion of lateral femoral condyle

• Cause:pivot shift injury = valgus load + external rotation of tibia / external rotation of femur applied to various states of flexion (noncontact injury)
• Predisposed: skier, football player
• Associated with injury of:
  1. anterior cruciate lig. (midsubstance >femoral attachment >tibial attachment site)
  2. posterior joint capsule + arcuate ligament
  3. posterior horn of lateral / medial meniscus
  4. medial collateral ligament
• ± edema of posterior patellar surface
• Cause: dashboard injury = force upon anterior proximal tibia with knee in flexed position
• Associated with:
  1. rupture of posterior cruciate lig. (midsubstance >femoral attachment >tibial attachment site)
  2. tear of posterior joint capsule
  3. fracture / osteochondral injury of patella
  4. injury of hip
• “kissing” bone contusion pattern = anterior aspect of tibial plateau + anterior aspect of femoral condyle
• Cause:hyperextension injury = direct force upon anterior tibia while foot is planted / indirect force of forceful kicking motion
• Associated with:
  1. injury to posterior / anterior cruciate lig.
  2. meniscal injury
  3. dislocation of knee
  4. popliteal neurovascular injury
  5. complete disruption of posterolateral complex
• edema in lateral aspect of femoral condyle ← direct blow
• small area of edema in medial femoral condyle ← avulsive stress to medial collateral ligament
• Predisposed: football player
• Cause:clip injury = pure valgus stress with knee in mild flexion
• Associated with injury of:
  1. medial collateral ligament (at femoral attachment site
  2. anterior cruciate ligament
  3. medial meniscus
  4. combination of all three = methyl triad
• anterolateral aspect of lateral femoral condyle
• inferomedial aspect of patella
• Predisposed: teenaged / young adult athletes with shallow trochlear groove
• Cause:lateral patellar dislocation = twisting motion with knee in flexion + quadriceps contraction
• Associated with injury of:
  1. medial retinaculum
  2. medial patellofemoral ligament (near femoral attachment site) most important stabilizing structure)
  3. medial patellotibial ligament