Klassifikation von Wirbelsäulenverletzungen nach Magerl, Aebi, Gertzbein, Harms und Nazarian

Anwendung

Frakturen

A Kompression 
A1 Impaktionsbruch
A1.1 Deckplattenimpression
A1.2 Keilbruch
A1.3 Wirbelkörperimpaktion
A2 SpaltbruchA2.1 frontaler Spaltbruch
A2.2 sagittaler Spaltbruch
A3.1 dislozierter frontaler Spaltbruch
A3 BerstungsbruchA3.1 inkompletter Berstungsbruch
A3.2 Berstungsspaltbruch
A3.3 kompletter Berstungsbruch
B Distraktion 
B1 transligamentäre FlexionsdistraktionsverletzungB1.1 mit Diskuszerreißung
B1.2 mit Korpusfraktur
B2 transossäre FlexionsdistraktionsverletzungB2.1 horizontale Wirbelzerreißung
B2.2 mit Zerreißung der Bandscheibe
B2.3 mit Korpusfraktur
B3 HyperextensionsscherverletzungB3.1 Hyperextensionssubluxation
B3.2 Hyperextensionsspondylolyse
B3.3 Hintere Luxation
C Torsion 
C1 Rotation mit KompressionC1.1 Rotationskeilbruch
C1.2 Rotationsspaltbruch
C1.3 Rotationsberstungsbruch
C2 Rotation mit DistraktionC2.1 Rotation mit B1
C2.2 Rotation mit B2
C2.3 Rotation mit B3
C3 RotationsscherbrücheC3.1 Slicefraktur
C3.2 Rotationsschrägbruch
  
Originalklassifikation
 
  
Type A
Vertebral body compression
The injuries are caused by axial compression with or without flexion and affect almost exclusively the vertebral body. The height of the vertebral body is reduced, and the posterior ligamentous complex is intact. Translation in the sagittal plane does not occur.
A1
Impaction Fractures
The deformation of the vertebral body is due to compression of the cancellous bone rather than to fragmentation. The posterior column is intact. Narrowing of the spinal canal does not occur. The injuries are stable, and neurological deficit is very rar.
A1.1
Endplate impaction
The endplate often has the shape of an hourglass. Minor wedging of up to 5 deg may be present. The posterior wall of the vertebral body is intact. The injury is most often seen in juvenile and osteoporotic spines.
A1.2
Wedge impaction fracture
The loss of anterior vertebral height results in an angulation of more than 5 degrees. The posterior wall of the vertebral body remains intact. The loss of height may occur in the upper part of the vertebral body (superior wedge fracture), in the inferior part of the vertebral body (inferior wedge fracture), or anterolaterally (lateral wedge fracture). The last is associated with a scoliotic deformity.
A1.3
Vertebral body collapse

This injury is usually observed in osteoporotic spines. There is symmetricalloss of vertebral body height without significant extrusion of fragments. The spinal canal is not violated. When combined with pronounced impaction of the endplates, the vertebral body has the shape of a 'fish vertebra'.

 

Note: Severe compression of the vertebral body may be associated with extrusion of fragments into the spinal canal and thus with injury to the spinal cord or cauda equina. Since those fractures show characteristics of burst fractures, they should be classified accordingly.

  
A2
Split fractures
As described by Roy-Camille et al. the vertebral body is split in the coronal or sagittal plane with a variable degree of dislocation of the main fragments. When the main fragments are significantly dislocated, the gap is filled wirh disc material which may result in a nonunion. Neurological deficit is uncommon. The posterior column is not affected.
A2.1
Sagittal split fracture
These fractures are extremely rare in the thoracolumbar spine. They usually occur as an accompanying lesion of rotation or burst fractures.
A2.2
Coronal split fracture
The smooth coronal fracture gap is narrow. The posterior vertebral body wall remains intact, and the injury is stable.
A2.3
Pincer fracture
The central part of the vertebral body is crushed and filled with disc material. The anterior main fragment is markedly dislocated anteriorly. The resistance to flexion compression is reduced, and pseudoarthrosis is likely to occur.
  
A3
Burst fractures
The vertebral body is partially or completely comminuted with centrifugal extrusion of fragments. Fragments of the posterior wall are retropulsed into the spinal canal and are the cause of neural injury. The posterior ligamentous complex is intact. The injury to the arch, if present, is always a vertical split through the lamina or spinous process. Its contribution to instability is negligible. However, cauda fibers extruding through a tear outside the dura may become entrapped in the lamina fracture. Superior, inferior, and lateral variants occur in burst fractures with partial comminution (A3.1, A3.2). In lateral variants with marked angulation in the frontal plane, a distractive lesion may be present on the convex side. The frequency of neural injury is high and increases significantly from subgroup to subgroup.
A3.1
lncomplete burst fractur
The upper or lower half of the vertebral body has burst, while the other half remains intact. The stability of these injuries is reduced in flexion-compression. In particular, fragments of the posterior wall of the vertebral body may be further retropulsed into the spinal canal when the injury is exposed to flexion/compression.
A3.2
Burst split fracture
In this injury, mentioned by Denis and described extensively by Lindahl et al., one-half of the vertebra (most often the upper half) has burst, whereas the other is split sagittally. The lamina or spinous processes are split vertically. Burst-split fractures are more unstable in flexion-compression and are more frequently accompanied by neurological injury than incomplete burst fractures.
A3.3
Complete burst fracture
The entire vertebral body has burst. Complete burst fractures are unstable in flexion-compression. Flexion and compression may result in an additional loss of vertebral body height. The spinal canal is often extremely narrowed by posterior wall fragments, and the frequency of neural injuries is accordingly high. 

A3.3.1: Pincer burst fracture. In contrast to the simple pincer fracture (A2.3), the posterior wall of the vertebral body is fractured with fragments retropulsed into the spinal canal. The vertebral arch usually remains intact.

A3.3.2: Complete flexion burst fracture. The comminuted vertebral body is wedge-shaped, resulting in a
kyphotic angulation of the spine. The lamina or spinous processes are split vertically.

A3.3.3: Complete axial burst fracture. The height of the comminuted vertebral body is more or less evenly reduced. The lamina or spinous processes are split vertically.
  
Type B
anterior and posterior element injuries with distraction

The main criterion is a transverse disruption of one or both spinal columns. Flexion-distraction initiates posterior disruption and elongation (groups B1 and B2), and hyperextension with or without anteroposterior shear causes anterior disruption and elongation (group B3).
B1
Posterior disruption predominantly ligamentous
The leading feature is the disruption of the posterior ligamentous complex with bilateral subluxation, dislocation, or facet fracture. The posterior injury may be associated with either a transverse disruption of the disc or a type A fracture of the vertebral body. Pure flexion-subluxations are only unstable in flexion, whereas pure dislocations are unstable in flexion and shear. Lesions associated with an unstable type A compression fracture of the vertebral body are additionally unstable in axial loading. Neurological deficit is frequent and caused by translational displacement and/or vertebral body fragments retropulsed into the spinal canal.
B 1.1
Posterior disruption predominantly ligamentous associated with transverse disruption of the disc
B 1.1.1. Flexion subluxation. In this purely discoligamentous lesion, a small fragment not affecting the stability may be avulsed by the annulus fibrosus from the posterior or anterior rim of the endplate. Neurological deficit is uncommon. 

B1.1.2: Anterior dislocation. This purely discoligamentous lesion with a complete dislocation of the facet joints is associated with anterior translational displacement and narrowing of the spinal canal. The injury is rarely seen in the thoracolumbar spine.

B 1.1.3. Flexion subluxation or anterior dislocation with fracture of the articular processes. Either of the previously mentioned B 1.1 lesions can be associated with bilateral facet fracture, resulting in a higher degree of instability, especially in anterior sagittal shear.
B1.2
Posterior disruption predominantly ligamentous associated with type A fracture of the vertebral body.
This combination might occur if the transverse axis of the flexion moment lies close to the posterior wall of the vertebral body. A severe flexion moment may then cause a transverse disruption of the posterior column and simultaneously a compression injury to the vertebral body which corresponds to an type A fracture.
B2
Posterior disruption predominantly osseous
The leading criterion is a transverse disruption of the posterior column through the laminae and pedicles or the isthmi. Interspinous and/or supraspinous ligaments are torn. As in the B 1 group, the posterior lesion may be associated with either a transverse disruption of the disc or a type A fracture of the vertebral body. However, there is no vertebral body lesion within type A that would correspond to the transverse bicolumn fracture. Except for the transverse bicolumn fracture, the degree of instability as well as the incidence of neurological deficit are slightly high er than in B1 injuries. Injuries belonging to this category have already been described by Böhler, who referred to a scheme designed by Heuritsch in 1933.

B2.1 
Transverse bicolumn fracture
This particular lesion was first published in the English-language literature by Howland et al. and illustrated even earlier by Böhler. The transverse bicolumn fracture usually occurs in the upper segments of the lumbar spine and is unstable in flexion. As it is a purely osseous lesion, it has excellent healing potential. Neurological deficit is uncommon.
B2.2
Posterior disruption predominantly osseous with transverse disruption of the disc
B2.2.1: Disruption through the pedicle and disc. This rare variant is characterized by a horizontal fracture through the arch that exits inferiorly through the base of the pedicle.  

B2.2.2: Disruption through the pars interarticularis and disc (flexion spondylolysis). A flexion spondylolysis with minimal displacement is less likely to result in neurological deficit. However, displaced fractures with pronounced flexion-rotation of the vertebral body around the transverse axis are frequently combined with neural injury. This is due to narrowing of the spinal canal as the posterior inferior corner of the vertebral body approaches the lamina.
B2.3
Posterior disruption predominantly osseous associated with type A fracture of the vertebral body
B2.3.1: Fracture through the pedicle associated wirh a type A fracture. The posterior injury is the same as described for B2.2.1.
 
B2.3.2: Fracture through the isthmus associated with a type A fracture. The posterior injury is the same as described for B2.2.2. The anterior column lesion is often an inferior variant of a type A fracture.
B3
Anterior disruption through the disc
 
B3.1
Hyperextension-subluxation
A spontaneously reduced, pure discoligamentous injury is difficult to diagnose. The presence of such an injury may be indicated by widening of the disc space and can be confirmed by magnetic resonance imaging scans. Discography may be helpful in the lumbar spine. Hyperextension-subluxations are sometimes associated with a fracture of the lamina or articular processes, or with a fracture of the basis of the pedicles.
B 3.2
Hyperextension-spondylolysis
The few cases seen by us were located in the lowermost lumbar level. In contrast to flexion-spondylolysis, the sagittal diameter of the spinal canal was widened in these cases, as the vertebral body had shifted anteriorly, while the lamina remained in place. Consequently, there was no neurological deficit. The cases described by Denis and Burkus occurred in the thoracic spine and were associated with severe neurological deficit.
B 3.3
Posterior dislocation
This is one of the severest injuries of the lumb ar spine and is often associated with complete paraplegia. Lumbosacral posterior dislocations probably have a better prognosis.
  
Type C
anterior and posterior element injuries with rotation

 
C1
Type A with rotation
This group contains rotation as wedge, split, and burst fractures. In type A lesions with rotation, one lateral wall of the vertebral body often remains intact.
C2
Type B with rotation
The most commonly seen C2 lesions are different variants of flexion-subluxation with rotation. Of the lateral distraction injuries published by Denis and Burkus, we would ascribe at least one to type B with rotation. Unilateral dislocations are less frequent. Boger et al. and Conolly et al. describe unilateral facet dislocations at the lumbosacral junction, and Roy-Camille et al. report auterior dislocation with rotation and unilateral facet fracture. Amongst distraction fractures of the lumb ar spine, Gumley et al. describe an injury which correspouds to the transverse bicolumn fracture with rotation.
C3: Rotational shear injuries
Holdsworth stated that the slice fracture is "very common in the thoracolumbar and lumbar regions and is by far the most unstable of all injuries of the spine." With regard to frequency, this does not correspond with our experience, which is limited to three cases. Thirteen of our 16 C3 injuries were oblique fractures. In our opinion, the oblique fracture is even more unstable than the slice fracture, as it completely lacks stability in compression. However, the slice fracture is obviously more dangerous to the spinal cord because of the shear in the horizontal plane.