A new classification for dislocated and displaced proximal humeral fractures.

Background: Although the Neer and AO/OTA classifications have been widely accepted, observer reliability studies of these two classifications have questioned their reliability and reproducibility to date. We developed an entirely new classification, the Mitsuzawa classification, for dislocated and displaced proximal humeral fractures and tested all three classifications for their intra- and interobserver reliability.

Methods: Two experienced shoulder surgeons and two orthopedic residents independently evaluated the Xray (xR) values of 100 proximal humeral fractures (PHFs).