Multifragmentary fractures of the humeral shaft with a fragmentary segment are classified as 12C3 fractures.
There are two main fragments, a proximal and a distal. After reduction there is no contact between the proximal and distal fragments. There is also a fragmented segment.
This fracture type is subdivided:
These fractures are rare and may follow high energy injury, such as high velocity missile wounds. They are therefore often open, and radial nerve injury is common. They tend to be very unstable.
Image taken from Orozco R, et al. Atlas of Internal Fixation. Paris: Masson; 1998. Used with kind permission.