The Carpal Bones

http://www.instantanatomy.net/arm/areas/hand/carpalbones.html

Fractures are 10 times less likely to occur than distal radial and ulnar injuries and are rare in children under 12. Injuries more likely in the proximal carpal row (scaphoid, lunate, triqetrum, pisiform).

TriquetrumThis is the second most fractured carpal bone accounting for 20%Z of carpal injuries. May be related to forced hyperextension. Normally seen as small triangular fragements or flake avulsions.
Treat with immobilisation in a POP backslab or wrist support splint, analgesia and refer to fracture clinic.

HamateThis is often caused by axial loading or punch type injury. Suspect if there is local palmar tenderness. Diagnosis can be difficult.

LunateFractures are uncommon, and mechanism is typically a direct blow to the carpus. Avascular necrosis may occur.

Pisiform
Direct blow or FOOSH.

Capitate
Axial loading of the middle metacarpal. Often missed.

Trapezoid
Rare. Axial loading of the index metacarpal.

Trapezium
Rare. Forced abduction of the thumb. Can mimic a scaphoid fracture.

All of these injuries should be referred to plastics?

http://www.memrise.com/course/59292/anatomy-of-the-hand/