TRIQUETRUM FRACTURES

Question 1

Classification of triquetrum fractures

Answer 1

Dorsal cortical fractures = most common
1. Impaction
- wrist in extension and ulnar deviation
- ulnar styloid acts as chisel and is driven into dorsal cortex
2. Avulsion
- wrist in flexion and radial deviation
- avulsion of dorsal radiocarpal (radiotriquetral) and triquetroscaphoid ligaments
3. Shear
Body fractures = 2nd most common
- may be part of a greater arc perilunate injury
Volar cortical fractures
1. Avulsion
- avulsion of ulnotriquetral and volar lunotriquetral ligaments
- may be associated with LT instability and VISI
2. Shear

Question 2

2 main extrinsic ligaments attaching to triquetrum

Answer 2

1. Volar side = ulnotriquetral ligament
   - volar aspect of TFCC to volar surface of triquetrum
2. Dorsal side = dorsal radiocarpal (radiotriquetral) ligament
   - dorsal DR to dorsal surface of triquetrum

Question 3

2 main intrinsic ligaments attaching to triquetrum

Answer 3

1. Volar side = volar lunotriquetral ligament
   - part of the LT interosseous ligament
   - stronger than dorsal component
2. Dorsal side = dorsal intercarpal ligament
   - dorsal triquetrum to dorsal scaphoid, trapezium and trapezoid

Question 4

2 surgical indications for triquetrum fractures

Answer 4

1. Fractures associated with carpal instability

2. Displaced body fractures

Question 5

2 main complications of triquetrum fractures

Answer 5

1. Carpal instability

2. Pisotriquetral arthritis