Case contributed by Dr. James Willard-Jones

Hook of Hamate fractures are uncommon, and account for <4% of carpal fractures. These fractures are often missed, causing delayed diagnosis and treatment. It is particularly important to identify these fractures as they are at risk of non-union. Hamate fractures are organized using the Milch Classification, which divides them into fractures of the Hook (type I) and Body (Type II). Hook fractures can be subsequently subdivided into three types: subtype 1 (distal tip), subtype 2 (body of hook) and subtype 3 (base of hook). The most common is subtype 3, as in the case above, which accounts for 75% of hook of hamate fractures¹.

While readily identifiable on CT imaging, the initial modality of plain radiographs can often obscure the diagnosis. As such, if there is a high clinical suspicion for a hook fracture then additional views are recommended in addition to the standard 3-views. These include (a) lateral view with thumb abduction and radial deviation, (b) supinated oblique and (c) carpal tunnel views.