- See:
- Burst Fractures
- Lumbar vertebrae:
- Discussion:
- typical injury pattern for burst frxs varies w/ anatomic level;
- L1 to L3 pedicles are frequently comminuted or detached;
- L4 to L5 frx usually present a consistent pattern:
- L4 & L5 pedicles are stout & usually remain intact;
- pedicles are usually not fractured & remain attached to caudal halves the vertebral body;
- kyphosis is usually not present;
- cephalad third of vertebral body is frx'ed w/ central retropulsion of bone into canal;
- significant stenosis may be present;
- displaced laminar fractures may entrap dura and cauda equina;
- neurologic injuries:
- neurologic injuries arising from lumbar burst fractures are less common and have a better prognosis than neurologic injuries
arising from thoracolumbar burst fractures;
- the reasons for this include, wider demensions of lumbar canal, larger and more stable posterior elements, and finally,
the lumbar canal is filled w/ cauda-equina (peripheral nerves) as opposed to spinal cord;
- even w/ initial nerve root paralysis, significant functional recovery will often occur with time;
- Exam:
- Non Op Treatment:
- consider NG tube if patient develops and ileus;
- total contact orthosis (w/ or w/o hyperextension) is worn for 4-6 months;
- leg extension must be added for fractures below L3;
- typically patients are allowed out of bed 3 to 14 days after injury, unless there are other concomitant injuries such as pelvic frx;
- whereas initial radiographs are taken supine, w/ long term follow up, radiographs need to be taken standing to evaluate for kyphosis;
- middle column can be disrupted at L4 to L5, but if posterior elements are intact or have only longitudinal frx, injury will be stable;
- wt bearing will be tolerated thru these posterior elements if pt is able to maintain normal lordosis;
- physiologic wt lordosis prevents excessive wt bearing & collapse in the middle column;
- L5 Burst Frx:
- most burst frx of L5 (w/o neurologic sx) may be treated w/ hyper-extension casting and thigh extension for 6-8 wks followed by
thorcolumbar orthosis for addition 3 months;
- thigh extension is generally required for all patients;
- the degree of compromise of the spinal canal is not directly related to the degree of neurological deficit (ie a large compromise
of the spinal canal did not necessarily result in a major loss of neurological function).
- repeat exam: is manadatory following hyper-extension casting, since nerve roots can be further impinged w/ extension;
- references:
- The effects of four types of support on the segmental mobility on the lumbosacral spine.
- Indications:
- neurologic signs accompanying lumbar frx may be similar to those of thoracolumbar fracture;
- r/o cauda equina syndrome:
- unstable Frx:
- disruption of posterior ligaments by acute hyperflexion injury in lumbar region produces unstable frx requiring internal fixation;
- Surgical Treatment:
- posterolateral approach for decompression of the spinal canal is effective at thoracolumbar & lumbar spine as a more direct means of
reducing the bony fragments;
- involves hemilaminectomy and removal of portions of one pedicle with high speed burr to allow posterolateral decompression of the
Dura along its anterior aspect;
- with angled instruments, the bone can be curreted out of the canal or tapped back into the vertebral body
Posterior fixation of thoracic and lumbar spine fractures using DC plates and pedicle screws.
Low lumbar burst fractures. Comparison among body cast, Harrington rod, Luque rod, and Steffee plate.
Comparison of operative versus nonoperative treatment of lumbar burst fractures.
The management of burst fractures of the fifth lumbar vertebra.