Ligamentotaxis with an internal spinal fixator for thoracolumbar fractures

Abstract

We assessed narrowing of the spinal canal in 39 burst fractures and fracture-dislocations of thoracolumbar vertebrae treated by the AO Internal Spinal Fixator, using CT preoperatively and at various stages postoperatively. Computer-aided planimetry was used to measure the narrowing, and its restoration shortly after instrumentation, or at 15 months. The mean initial reduction of canal area was to 63.7% +/- 18.8% of normal; this was restored to a mean of 95.4% +/- 21.2% of normal when measured either soon after surgery or at 15 months (p < 0.001 for both groups). There was more improvement in cases assessed later. For fractures from D12 to L3, the mean canal area was restored to 99.4% of normal; but at L4 or L5 the mean restitution was to only 60.9% (p < 0.05). We found no correlation between preoperative loss of area and amount of restoration, or severity of neurological deficit. Nor was there any correlation between the delay before surgery and the improvement achieved. The mechanism of fracture reduction appears to be a combination of distraction ligamentotaxis and forced hyperextension.

Anterior versus posterior approach for treatment of thoracolumbar burst fractures: a meta-analysis

“…This approach provides better exposure of the fractured vertebrae, enabling a more thorough decompression [10]. In contrast, the posterior approach can only support indirect decompression [31]. Therefore, good canal remodeling after canal encroachment occurred in the anterior approach group just as all the included studies concerning this parameter.…”

Treatment of thoracolumbar burst fractures without neurologic deficit by indirect reduction and posterior instrumentation: bisegmental stabilization with monosegmental fusion

“…Recent studies have shown that posterior indirect reduction corrects the canal compromise adequately due to a combination of distraction ligamentotaxis and forced hyperextension [26,34]. The canal compromise remaining postoperatively may further decrease to near normal over time due to the pulsations of the thecal sac [5,23].…”

The Ligamentotactic Effect on a Herniated Disc at the Level Adjacent to the Anterior Lumbar Interbody Fusion : Report of Two Cases

“…Originally, ligamentotaxis was defined as a method for indirect reduction of a fracture by the application of a strong distraction force, which is transmitted through intact ligaments and capsules 1) . This phenomenon is applied mainly to the thoracolumbar burst fracture.…”

“…However, a prerequisite for ligamentotaxis is an intact PLL and attachment of the retropulsed fragments to the ligament 2) . In addition, the effect of ligamentotaxis is weak below the L3 level for anatomical reason 1) . Therefore, the A ligamentotatic effect on disc herniation may be applied to the contained disc herniation above the L3/4 level.…”