In the true AP elbow the patient’s arm is fully extended with the shoulder, elbow and forearm in the same horizontal plane. The forearm is supinated (palm up) so the medial and lateral epicondyles are parallel to the image receptor and the radius and ulna lie parallel. The central X‑ray beam is directed perpendicular to the elbow joint at the mid‑joint region.

An elbow X‑ray typically includes an anteroposterior (AP) view, a lateral view, and often an oblique (or radial head) view. AP shows joint alignment and the distal humerus, lateral visualizes the olecranon, coronoid and anterior/posterior relationships, and oblique highlights the radial head and coronoid process. Additional targeted views assess suspected occult fractures or dislocations.

The AP (anteroposterior) view is an X‑ray projection where the beam travels from the patient’s front (anterior) to back (posterior). It’s commonly used for supine, immobile, or portable chest radiographs. AP films can magnify the heart and mediastinal structures and may look different from standard PA views, so readings account for patient position and technical limitations.

Elbow AP and lateral are standard X‑ray views—AP (anteroposterior) and lateral projections—used to evaluate the distal humerus, proximal radius and ulna. AP assesses joint alignment, bone contours and medial/lateral displacement; lateral shows anterior/posterior displacement and occult fractures (including the fat‑pad sign). Both views are routinely done for trauma, pain, suspected fracture or dislocation to guide management.

Identify PA versus AP by patient and image clues: PA is taken standing with chest against the detector—scapulae lie outside the lung fields, clavicles appear symmetric and higher, and heart size is true (less magnified). AP, often portable or supine, shows scapulae projected over lungs, clavicles more horizontal, apparent cardiomegaly from magnification, poorer inspiration, and often an AP marker or bedside gear visible.

Hang a right elbow X‑ray as if the patient faces you: the patient’s right side should appear on your left and an R marker must be visible. Orient the image with the humerus/proximal arm superior and the forearm/distal segment inferior. For lateral views, the elbow is flexed 90° with the patient’s lateral aspect toward the detector. Confirm marker placement and correct view.