Mechanism of flexion injuries.
(A) In the flexed elbow, force develops on the posterior aspect of the olecranon (small double arrow) because of the pull of the brachialis and triceps muscles (large arrows).
(B) Failure occurs on the tension side, which is posterior as a result of the muscle pull or a direct blow to the prestressed posterior olecranon.
Reproduced with permission from: Erickson M, Frick S. Fractures of the proximal radius and ulna. In: Rockwood and Wilkins' Fractures in Children, 7th ed, Beaty JH, Kasser JR (Eds), Lippincott Williams & Wilkins, Philadelphia 2010. Copyright © 2010 Lippincott Williams & Wilkins.
www.lww.com.
