86 Lumbar Burst Fracture

Ahmed Jaman Alzahrani and Khalid N. Almusrea

Fig. 86.1 (A) Computed tomography scan of the lumbar spine with axial section through L3 and (B) sagittal reconstructed image.

Clinical Presentation

A 70-year-old man presents 4 days after a motor vehicle accident, transferred from a local hospital, with the complaint of severe lower back pain.

The pain radiates to left thigh in an L3 dermatomal distribution.

On examination he is neurologically intact.

He has an unremarkable past medical history.

A computed tomography (CT) scan of the lumbar spine was done at the local hospital (Fig. 86.1).

Questions

Describe the CT images.

What is your initial management?

Magnetic resonance imaging (MRI) is obtained and pertinent images are shown in Fig. 86.2.
What are the findings of the MRI of the lumbosacral spine?
What is your management now?
What are possible complications of nonoperative management in this case?
Describe indications for surgery in burst fractures.
What surgical approach will you choose and why?
What are the potential complications of a posterior surgical approach?
What are the outcomes of this approach?

Fig. 86.2 Magnetic resonance imaging scan of the lumbar spine with (A) T2-weighted sagittal section and (B) axial section images through L3.

Answers

Describe the CT images.

There is a type A Denis burst fracture of the L3 vertebra.
Loss of height of ~40% and kyphosis of 15 degrees are evident.
There is canal compromise of ~50%.

What is your initial management?

Ensure the initial trauma workup has been completed (airway, breathing, circulation [ABCs], etc.).
Complete spinal precautions (logroll only).
Obtain radiographs of the rest of the spine and further CT scans if other fractures are seen.
Place the patient on adequate pain management.
Obtain basic laboratory panel including complete blood count (CBC), electrolytes, coagulation profile.
Obtain an MRI of lumbosacral spine to assess any neural element and ligamentous involvement.
You may also elect to order an external orthosis, preferably a Jewett or thoracolumbar spinal orthosis brace in this case.

What are the findings of the MRI of the lumbosacral spine?

The MRI confirms the severe compromise of the thecal sac.
There is left L3 foraminal stenosis.

What is your management now?

Treatment options include

Conservative treatment with bracing, physical therapy, and pain control.¹

Surgical fixation with decompression and fusion via an anterior, posterior, or combined approach.^2,3

With the presence of significant canal stenosis and root compression, surgical intervention may be a better option.
What are possible complications of nonoperative management in this case?
- Persistent and worsening instability (mechanical, neurologic)
- Increased kyphosis leading to neurologic deficit or intractable pain ⁴
- Further collapse of the affected vertebra with cauda equine syndrome
Describe indications for surgery in burst fractures.
- Features of instability that lead to the requirement for surgical fixation include the following⁵:
  - Neurologic deficit
  - Canal compromise of ≥50%
  - Height loss of ≥40%
  - Kyphosis of ≥30 degrees
What surgical approach will you choose and why?
- Posterior decompression and fixation is preferred because an anterior approach will need major exposure despite no major difference in outcome, especially in an elderly patient as in this case.^3,6 (This is our personal preference; however, the choice of the approach is debatable and remains controversial.)
What are the potential complications of a posterior surgical approach?
- In a series of 76 patients with thoracolumbar fractures, the complication rate was ~3.6%.⁷
- Complications include the following^7–9:
  - Pain
  - Neurologic deficit
  - Postoperative infection
  - Progression of the kyphosis
  - Nonunion or lack of fusion
  - Rupture or loosening of the implants
  - Loss of correction and required placement of an anterior support graft
  - Vertebral arch fracture
  - Epidural hematoma
  - Inadequate decompression
  - Cerebrospinal fluid leak
What are the outcomes of this approach?
- Results are varied and depend on the studied parameters and institution.
- Significant differences have been shown between the immediate postoperative and late postoperative outcomes in terms of height restoration when a posterior approach is used alone.⁸
- The neurologic recovery from burst fractures is not predicted by the amount of initial canal encroachment or kyphotic deformity.¹⁰
- In burst fractures without a neurologic deficit, there is no superiority of conservative therapy over operative therapy.¹⁰ One prospective trial on 80 patients without neurologic deficits showed that posterior fixation provides partial kyphosis correction and earlier pain relief, but the functional outcome at 2 years is similar to a conservatively treated group.¹¹
- When there is significant neurologic involvement, operative management is advised. However, there is no obvious superiority of one approach over the other.¹⁰
- In a series of 28 patients treated via posterior approach, there was 82% neurologic improvement.⁹
- A retrospective review of 46 patients with encroachment of the spinal canal greater than 50% treated surgically showed that there is no significant difference in clinical outcome between those treated with a combined approach (anterior and posterior) versus those treated with a posterior approach alone. Furthermore, neurologic deficits improved by at least one Frankel grade in both cases for the most part. ¹²