injuries poisoning
Radial Head Fractures
Diagnosis of Radial Head Fractures
Physical examination X-rays Anteroposterior, lateral, and oblique views are taken. But because x-rays may show only indirect evidence of fracture, diagnosis relies heavily on physical examination. Routine anteroposterior and lateral x-rays often do not show the fracture but usually show a joint effusion, which is indicated by the presence of abnormal fat pads on x-rays. Displacement of the anterior fat pad may indicate joint effusion but is not specific; visibility of the posterior fat pad on a true lateral view is specific for joint effusion but not highly sensitive. Patients with localized radial head tenderness and effusion require oblique views (which are more sensitive for fracture) or presumptive treatment of a fracture. Anterior humeral line and radiocapitellar line None If the radial head is tender and there is clinical or radiographic evidence of an elbow effusion, treat presumptively for radial head fracture even if the x-ray shows no fracture. Arthrocentesis may be done to remove blood from the joint to help differentiate mechanical blockage of passive joint motion from restriction due to pain and muscle spasm. Then, a local anesthetic is injected to relieve pain. Stability is tested by applying stress to the elbow medially and laterally and checking for laxity or increased motion. If the joint does not move when stress is applied, the fracture is stable and associated ligaments are probably uninjured. Normally, the anterior humeral line, which is drawn along the anterior border of the humerus on a lateral x-ray, transects the middle of the capitellum. If the line transects none or only the anterior part of the capitellum, a distal humeral fracture with posterior displacement may be present. The radiocapitellar line, which is drawn through the midshaft of the radius, normally bisects the capitellum. If it does not, an occult fracture should be suspected. 