====== Gehweiler classification of atlas fractures ====== {{::gehweiler_classification_of_atlas_fractures.jpg?400|}} The Gehweiler classification of [[atlas fracture]]s described 5 types of fractures of the atlas. In addition, Dickman classified injuries of the transverse atlantal ligament (transverse band of the cruciform ligament) which has been incorporated into this classification system. see [[Dickman Transverse Ligament Injuries Classification]]. ---- type 1: fractures of the anterior arch type 2: fractures of the posterior arch and are usually bilateral type 3: fractures involving the anterior and posterior arch ([[Jefferson fracture]]) type 3a: intact transverse atlantal ligament type 3b: disrupted transverse atlantal ligament complex ---- Dickman type 1: ligamentous disruption Dickman type 2: bony avulsion with an intact ligament transverse atlantal ligament type 4: fractures of the lateral mass type 5: isolated fractures of the C1 transverse process ((Gehweiler JA, Osborne RL, Becker RF. The Radiology of Vertebral Trauma. St. Louis, MO: WB Saunders; 1980.)).