- Criteria for Unstable Frx:
- Neurologic deficit;
-
Posterior Element Injuries;
- Loss of more than 50% of anterior vertebral body height;
- Greater than 25 to 35 deg of kyphosis;
-
Thoracolumbar burst frx:
- angulation of thoracolumbar junction > 20 deg
- canal comprimise > 30 percent
- Treatment:
-
Anterior Approach
-
Distraction Systems:
-
Multisegmented Hook Instrumentation
-
Posterolateral Decompression:
- Discussion:
- in
stable bust frxs,
posterior column is uninjured & remains functional as tension band
wheras unstable burst frx have comminution or ligamentous damage to
posterior column;
- axial force will builds up sufficient pressure in disc to centripetally frx superior portion of vertebral
body in all directions;
- fragments usually remain attached to annulus & are contained w/ in intact anterior and
posterior longitudinal ligaments;
- unstable burst frx are prone to further collapse & retropulsion upon normal axial loading;
- w/ severe compression frx (over 70% of the vertebral body), there will also be concomitant
disruption of interspinous ligament;
- frx will often settle into
kyphosis with time;
