Synonym: traumatic malacia (lunatomalacia)
Risk factors relate to vascular supply or increased mechanical load
(1) limited vascular supply
(2) small lunate size
(3) decreased radial inclination angle
(4) ulna minus (negative variance)
Lichtman's classification
|
Radiographic Finding
|
Stage
|
|
changes of the acute injury, with altered density on MRI
|
I
|
|
increased density
|
II
|
|
collapse of the lunate
|
III
|
|
pan-carpal arthrosis
|
IV
|
Stage III was subsequently subdivided based on the radioscaphoid angle and coronal fracture.
|
Radioscaphoid Angle
|
Stage III
|
|
<= 60°
|
IIIA
|
|
> 60°
|
IIIB
|
Stage III with coronal fracture was Stage IIIC.
Complications:
(1) scapholunate dissociation
(2) degenerative arthrosis
(3) malalignment of the triquetrum
(4) limited wrist motion
(5) pain in the dorsal wrist
