Pitfalls in this surgery were a narrow operative field, which yielded to oblique positioning of the cage with respect to L4–S1 endplates. In our series, only one patient has been treated with an anterior approach. Corpectomy and lateral plating across the lordotic segments can be technically demanding. Nevertheless, lumbosacral anterior approach may be difficult due to major vessels (sometimes adherent to the injured vertebra) and lack of specific L4–S1 instrumentations. The anterior approach may be an option when decompression and/or reconstruction is needed, and somatectomy may be performed in association with a cage body replacement as it is performed at the thoracolumbar junction. Another issue includes the role of impaction on preventing post-traumatic modifications in load-sharing forces, which are mostly exerted on the posterior half of the vertebral body. Most often, we performed fragment impaction, as we think it allows complete canal decompression. Migrated bony fragment may be either impacted or removed, whereas chances for ligamentotaxis are considered to be limited. Rod contouring, together with definitive fixation performed with extended hips and knees, seems to help in preventing kyphosis and sacral verticalization. We always aimed at lordotic contouring of the instrumentation, as many authors reported better results when spino-pelvic profile was unmodified. When intact pedicles were found at L5, short transpedicular screws can be used at the aforementioned level. In our experience, the great majority of patients were treated by L4–S1 instrumentation, and only one needed 元 fixation due to a concomitant L4 fracture. Anterior interbody expansion cage via posterolateral approach may also be an option. Posterior decompression is easily associated with pedicular screw fixation, and transpedicular bone implantation is also possible. By contrast, compression of neural tissue associated with complete motor impairment is mandatory for laminectomy and/or arthrectomy, the last depending on whether facet dislocation is present. When no neurological impairment was seen, conservative treatment including bracing and rest yielded satisfactory results in several series. This may lead in turn to disc herniation and/or degeneration, and either bony or disc fragments may determine narrowing of the spinal canal. Comminution of the vertebral body may be significant in type A3.1 and most of all in type A3.3 fractures. The L5 fractures are most frequently due to axial compression forces. Canal remodeling was a common finding in CT and X-ray studies, with no secondary stenosis (Fig. Fifteen individuals (79%) had no or intermittent pain (score of 0 or 1), whilst four patients (21%) had continuous but not invalidating pain (score of 3). The remaining eight patients (43%) had isolated, mild or moderate sphincter impairment. Three patients (15%) were finally paralyzed (score 0 or 1). In five patients (26%), complete neurological recovery was observed (score 7), whereas in three (15%), some distal impairment (score from 3 to 5) was still appreciable (three of them had associated marked sphincter deficits). At follow-up evaluation, vertebral bodies remained deformed due to height loss, though rod contouring allowed an acceptable final lumbar profile (L4–S1 angle mean 22°, range 20–35) (Fig. That resulted in an oblique positioning of the titanium cage. Cage positioning, in the only patient with a circumferential approach, was difficult due to a narrow operative field. No major complications were associated with operative technique or construct failure. Post-operative and follow-up (mean 22 months, range 10–66) evaluation included neurological improvement, pain, canal remodeling and L4–S1 angle measurement. Operating table position included extended hips and knees, in order to obtain reduction of kyphosis and achieving a lordotic fixation. Twelve patients had sphincter impairment, marked (score 1) in eight cases or moderate (score 2) in four. Peripheral motor impairment, involving feet and ankles, was found in all patients, with 6 presenting with severe impairment (score of 0 or 1) and 13 with moderate symptoms (score 2) (Table 1). One patient had an associated L4 burst fracture and another one a stable L1 fracture. Disc herniation was found in three patients, whilst four patients had dural tears. The dislocated bony fragment was impacted towards the vertebral body in 11 patients, whereas it was removed by anterior approach in one patient. The only exception was an A3.3 highly comminuted fracture treated by circumferential approach. All but one patient underwent laminoarthrectomy, pedicle fixation, and posterolateral fusion. Of them, 3 were affected by type A3.1 fractures and 16 presented with type A3.3 fractures. We enrolled 19 consecutive patients with L5 neurological fractures since 1999 to 2008 (14 males, 5 females mean age 35, range 22–50).
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