Not all wrists are "Clinical Scaphoid" 3

A middle aged lady fell hard, breaking some furniture in the process.  She had tenderness all over the wrist (including ASB and ulnar aspect), and these Xrays.  What do they show?  How do you manage it?

It's a broken triquetrum (-al).  They may be fractured by means of impingement from the ulnar styloid, shear forces, or avulsion from strong ligamentous attachments, classically from a hyperextension injury with the wrist in ulnar deviation (although not always – flexion has also been described).  It is the second commonest carpal bone fracture, after the scaphoid.

Avulsion fractures usually show as a flake off dorsal the surface on the lateral view and typically (but not always) occurs with a wrist hyperextension injury. These account for up to 93 percent of triquetral fractures.    Avulsion fractures are treated with immobilization for 4-6 weeks and follow up in fracture clinic and generally cause no problems. The flake doesn’t always come from the triquetrum, but rarely needs additional management (fantastic paper ;)  ).

Midbody fractures are less common and are usually high energy injuries such as a direct blow. They may occur in conjunction with a perilunate dislocation (12 to 25%) and are more often seen on the AP than the lateral.  Displacement and also occult injuries are not uncommon and may be underestimated and so CT should be performed for all of these, in wrist clinic if not acutely.