Fracture classifications
(author: Thammo Weise)

The number of vertebral fractures differentiated in the literature in the thoracic and lumbar region alone far exceeds 60 (according to F. Magerl, M. Aebi, S. Nazarian); these are precisely described with a combination of letters and numbers. Three main groups are classified depending on the cause of the fracture. The upper case letter A encompasses fractures arising from compressive forces (pressure), which, above all, affect the vertebra itself. Strain and bending fractures are identified with B and vertebral fractures from dislocations due to torsion (twisting) with C. Structures of the bone in the immediate vicinity can be damaged here. There can, of course, be several causes, especially in the case of traumatic fractures whose classification is undertaken according to the most serious cause. So a torsion fracture with associated compression is therefore categorised as C. In addition, fractures are described according to their shapes. Class 1 compression fractures (A) characterise the general loss of bone height due to depression of the vertebral end-plates, Class 2 fractures the origin of a split and Class 3 through bursting. The subsequent numbers serve to precisely describe the localisation and orientation of the fracture. In theory, fractures can occur in the sagittal, frontal and transversal planes. They can completely sever the vertebra, detach part of the bone, propagate radially or simply cause small fissures. The addition of the lower case letters a or b describes whether the fracture is mainly in the front (anterior) or rear (posterior = b) region. For example, the fracture specification A3.1a means an incomplete burst fracture in the front region of the vertebra due to compression. As diverse and obscure the classification may appear to the medically uninitiated, it serves doctors as a means of arriving at a clear indication for the use of a cement-based augmentation technique. Although the guidelines of the German Radiology Society do not adopt a position on vertebroplasty and kyphoplasty in regard to the fracture variants (with the exception of posterior edge defect), the literature indicates a difference in the two established techniques (insofar as this subject is addressed at all). According to current knowledge, in particular split fractures (A2), burst fractures (A3.2) and complete burst fractures (A3.3) are unsuitable for kyphoplasty. Firstly it is assumed that the split components are not sufficiently stabilised with cement augmentation, and secondly, in the case of burst fractures, the positioning of the balloon causes displacement of the individual splits such that the risk of cement escaping is increased. Balloon kyphoplasty can only be used to a limited extent for the analogous fractures in the B group (B1.2 and B2.3) and combination with internal fixation is recommended. The typical osteoporotic fractures, such as cover plate compression (A1.1), wedge fracture (A1.2), “fish vertebra” fracture (A1.3) and incomplete burst fracture (A3.1) can all be treated the same with both techniques. Irrespective of which main group, certainly not every vertebral fracture can be treated unconditionally with a minimalinvasive technique and stabilising bone cement, but a restriction of kyphoplasty, as described above, has so far not been undertaken for vertebroplasty.

SOMATEX offers an extensive range of vertebroplasty sets and accessories and so meets the various requirements for fracture augmentation with bone cement. Depending on the handling preferred, the user can select between different sets and packages. From the universal “Apart-Standard-Set“ as the basic solution, up to the “DUAL complete“ all-inclusive package, Somatex offers individual solutions. Besides the bone cement specially developed for vertebroplasty, in which hydroxyl apatite components are mixed, Somatex offers various separate components. Furthermore, diverse information materials, such as patient information brochures, patient consent forms or DRG (Diagnosis Related Groups for Germany) coding examples are available.

Sincerely yours, Thammo Weise