1 Introduction topenlarge
B1 injuries indicate monosegmental pure osseous failure of the posterior tension band. They are also called Chance fractures. The vertebral body and the posterior tension band have failed in flexion distraction mode through the bony structures.
2 Closed reduction topenlarge
Primary reduction is performed by positioning of the patient onto a frame to create lordosis.
3 Reduction with pedicle screws topenlarge
Due to the fact that bilateral instrumentation is necessary in all cases, all steps described below are repeated on the opposite side, unless described otherwise.
Pedicle screw insertion
Most B1 fractures, being pure osseous disruptions, have excellent healing potential and can be managed by posterior short segment fixation with pedicle screws alone.
Pedicle screws are inserted into the vertebrae cephalad and caudal to the fracture level on both sides. Mono- or polyaxial, top- or side loading screws can be used in any combination. ( Pedicle Screw Insertion)
The contouring of the rod depends on the site of the fracture following the natural curvature of the spine. A rod contoured in mild kyphosis is chosen for fractures from T1-T10. A straight or a slightly lordotic rod is chosen for fractures from T11-L1 as illustrated, and a rod contoured to lordosis is chosen for lumbar fractures.
The rods are introduced to the distal screw heads on both sides and tightened.
The rod is then inserted into the proximal screw heads without tightening.
The screw heads are tightened with the inner nuts to secure the reduction achieved.
The final construct is shown from a lateral view.
4 Fusion top
Although fusion was routinely performed for all spinal fractures, its indications are now being restricted to fractures that are highly unstable.
Nonfusion fixations can be performed for A3, A4, and B1 type injuries. Fusion is routinely performed for A2, B2, B3 and all C injuries as they are unstable injuries with extensive soft tissue and ligamentous disruption.
For nonfusion surgeries, the facet joint capsule is preserved during the entire procedure.
The screws can be removed after 9 months once the fracture has healed.