Discussion:

       - 5-10% of all supracondylar frxs
       - occurs from fall w/ elbow flexed as it hits the ground;
       - posterior cortex fails first;
       - resulting frx has anterior displacement of the distal fragment in sagittal plane, and lateral/valgus displacement in coronal plane
       - fracture line courses from below upward and forward;
       - soft tissue swelling and damage are usually much less than in the extension type and neurovascular complications are rare;
       - ulnar nerve palsy occurs in some cases; injured by the sharp spike of proximal fragment
       - classfication:
                 - can use a similar classification scheme as extension type injury: types I, II, III
                 - type I: undisplaced or minimally displaced, cast/splint
                 - type II:
                       - inegrity of anterior cortex remains, but with anterior displacement of distal fragment
                       - reduce and cast in extension, 
                       - may need pinning
                 - type III: complete displacement, usually requires open reduction and percutaneous pins

Flexion-Type Supracondylar Humeral Fractures: Ulnar Nerve Injury Increases Risk of Open Reduction

Low incidence of flexion-type supracondylar humerus fractures but high rate of complications

Operative Management of Displaced Flexion Supracondylar Humerus Fractures in Children