The olecranon (, from Greek olene 'elbow' and kranon 'head'), is a large, thick, curved bony process on the proximal, posterior end of the ulna. It forms the protruding part of the elbow and is opposite to the cubital fossa or elbow pit (trochlear notch)...
Displaced fracture of olecranon process without intraarticular extension of unspecified ulna, subsequent encounter for open fracture type I or II with routine healing
Displaced fracture of olecranon process with intraarticular extension of unspecified ulna, subsequent encounter for open fracture type IIIA, IIIB, or IIIC with routine healing
