Schenck classification of knee dislocation

TheThe Schenck classification is categorizing categorising knee dislocation based on the pattern of multiligamentous injury:

This classification is based onligament tears. The four major ligamentous stabilisers are the pattern of ligamentous involvement in the knee dislocation.

Four major ligament stabilizers are :

The anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), medial collateral ligament (MCL) and the posterolateral corner [PLClateral collateral ligament (LCL) complex.

Posterolateral corner contains many dynamic and static stabilizers.

All the fourFive patterns of major injuries are disruptedseen in about 11% of cases.

 Schenck classificationknee dislocations (KD), each designated by a Roman numeral, from I to V. 

·    

• KD I: Multiligamentous injury with the involvement involvement of the ACL or PCL

  ·    

• KD II: Injuryinjury to both ACL and PCL only (2 ligaments), with both collateralcollaterals intact (rare)

  ·    

  • rare

• KD III: injury to both ACL,  and PCL, and either the LCL or MCL

  o    KDIIIM (ACL, PCL, MCL) and

  o    KDIIIL (ACL, PCL,MCL or LCL /posterolateral corner are injured- not both - torn

  • KDIIIM (if MCL torn).
  • KDIIIL (if LCL torn) 

    ·    

• KD IV: Injury to ACL, PCL, LCL & MCL (4all 4 ligaments) 

  o    KDIV has the torn

  • highest rate of vascular injury (5-15%%)

    ·    

• KD V: Multiligamentousmultiligamentous injury with periarticular fracture
  • i.e. knee fracture-dislocation

C  (added to above ) – arterialAdditional letter designators indicate the presence of neurovascular injury:

• C: popliteal artery injury
• N (added to above) –: peripheral nerve injury icluded
  • any deficit: neuropraxia, neurotmesis, or axonotmesis
    • peroneal nerve (more common)
    • tibial nerve

It is important if tendinous injuries, avulsions of the biceps femoris, tibial tubercle, and/or quadriceps tendon tears are present, in which cases additional descriptor(s) is/are documented.