The Olecranon Bursa

SUMMARYThe olecranon bursa is a potential cavity in the normal subject and is represented by two layers of synovial membrane and extrasynovial fat. It is only the extrasynovial fat that is seen on the normal lateral view of the elbow.When the cavity of the bursa is distended at post‐mortem examination with 1 ml. of barium sulphate suspension, a smooth‐walled sac that fits like a cap over the tip of the olecranon process is outlined. The bursa is noted to be separated from the ulna by a thin layer of translucent extrasynovial fat.A 21‐gauge scalp vein needle forms a useful cannula when performing bursography. The tip of the needle must be in contact with the ulna to give satisfactory filling of this potential cavity.