What classification system is most frequently used for proximal humeral fractures?
The Neer classification, described in 1970.
According to the Neer classification, how many parts is the proximal humerus divided into? What are they?
Four parts: humeral head bearing the articular surface; greater tuberosity; lesser tuberosity; humeral shaft. Fractures separating the articular surface of the humeral head from the rest of the proximal humerus are termed anatomical neck fractures. Fractures separating the shaft from the humeral head and the tuberosities are termed surgical neck fractures.
In the Neer classification, would this be a one, two, three or four part fracture? Why?
A little counterintuitively this would be considered a one-part fracture, as although both a greater tuberosity and surgical neck of humerus fracture are present neither are significantly displaced (<1 cm) nor are they significantly angulated (<45 degrees).
What proportion of all proximal humeral fractures are one-part (minimally displaced) according to the Neer classification?
How are un-displaced / minimally displaced (one part fractures) usually treated?
Conservative management, with sling usually suffices and results in acceptable functionality.
The three fragments to this fracture are visible on the AP view: humeral head (red), humeral shaft (blue) and greater tuberosity (yellow). These are minimally displaced and only mildly angulated.