The trochlear notch (semilunar notch) of the ulna is the large C-shaped articular surface of the proximal ulna that wraps around the trochlea of the humerus to form the humeroulnar joint. It is bounded proximally by the olecranon and distally by the coronoid process, with its articular cartilage interrupted by a transverse non-articular ridge at its midpoint.
The trochlear notch is the site of olecranon fractures (proximal component) and coronoid fractures (distal component). Comminuted fractures spanning the entire notch (trans-olecranon fracture-dislocation) require careful reconstruction of the articular surface to restore elbow congruence. The non-articular transverse ridge is a normal anatomical variant and must not be confused with an articular surface fracture on imaging. Cubitus varus and valgus deformities alter trochlear notch tracking.
This website uses cookies to enhance your experience. Some are essential for site functionality, while others help us analyze and improve your usage experience. Please review your options and make your choice.
If you are under 16 years old, please ensure that you have received consent from your parent or guardian for any non-essential cookies.
Your privacy is important to us. You can adjust your cookie settings at any time. For more information about how we use data, please read our privacy policy. You may change your preferences at any time by clicking on the settings button below.
Note that if you choose to disable some types of cookies, it may impact your experience of the site and the services we are able to offer.
Some required resources have been blocked, which can affect third-party services and may cause the site to not function properly.
This website uses cookies to enhance your browsing experience and ensure the site functions properly. By continuing to use this site, you acknowledge and accept our use of cookies.
