classification of fractures of mandible, fractures of midface, fractures of zygomaticomaxillary complex, fractures of NOE (facial fractures). Zygomaticomaxillary complex (ZMC) fractures, also known as a tripod, tetrapod, quadripod, malar or thoracolumbar spinal fracture classification systems. ZMC complex fracture. Tripod fx Right zygomaticomaxillary complex fracture with disruption of the lateral orbital wall, orbital floor, zygomatic arch and maxillary sinus. The zygomaticomaxillary complex fracture, also known as a quadripod fracture, quadramalar Classification. D · ICD .
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The Comprehensive AOCMF Classification System: Midface Fractures – Level 3 Tutorial
This tutorial outlines the details of the AOCMF image-based classification system for fractures of the midface at the precision level 3. The topography of the different midface regions central midface—upper central midface, intermediate central midface, lower central midface—incorporating the naso-orbito-ethmoid region; lateral midface—zygoma and zygomatic arch, palate is subdivided in much greater detail than in level 2 going beyond the Le Fort fracture types and its analogs. The level 3 midface classification system is presented along with guidelines to precisely delineate the fracture patterns in these specific subregions.
It is easy to plot common fracture entities, such as nasal and naso-orbito-ethmoid, and their variants due to the refined structural layout classificatuon the subregions. As a key attribute, this focused approach permits to document the occurrence of fragmentation i. Moreover, the preinjury dental state and the degree of alveolar atrophy classifixation edentulous maxillary regions can be recorded.
On the basis of these individual features, tooth injuries, periodontal trauma, and fracture involvement of the alveolar process can be assessed.
Classification and treatment of zygomatic fractures: a review of 1,025 cases.
Coding rules are clsasification to set up a distinctive formula for typical midface fractures and their combinations. The instructions and illustrations are elucidated by a series of radiographic imaging cpassification. A critical appraisal of the design of this level 3 midface classification is made. The AOCMF craniomaxillofacial fracture classification system was developed in the form of a hierarchical three-level system with increasing details and complexity.
The facial skeleton is composed of multiple singular or paired bones that are articulated by fixed sutures. The overall framework is subdivided into a few major topographical regions predisposed to typical fracture entities e. The precision level 3 midface fracture classification adds a new layer of elaboration going beyond the basic level 2 topographic assessment in these subregions in more detail. Fragmentation, displacement, and bone loss are the descriptors to refer to fracture morphology within these layouts.
Rules for coding the fracture location and the morphologic variables are established.
To account for a more selective analysis of the individual patient’s pretrauma condition, the dentition and the degree of atrophy in the maxillary processes in case of partial or total edentulism are recorded. These features serve as a baseline to document tooth injuries, periodontal trauma, and alveolar process fractures. A series of case examples with clinical imaging points out the modalities of this midface level 3 classification. It is recommended to revisit the midface level 2 tutorial 2 briefly before passing on.
The midface level 3 classification system is introduced in the following sections covering specific anatomical subregions of fractured central and lateral midface. Fracture morphology in the central midface is documented by fragmentation, displacement, and bone loss. So-called multifragmentary or, in outmoded parlance, comminuted fractures, representing fractures in which bone is shattered, splintered or crushed into many pieces, are included in the latter category.
Displacement is attested whenever the fragments have moved out of their original location and lack alignment to the skeletal superstructure regardless of the metric amount. Traumatic bone loss, also referred to as bone defect dapplies to deficits ranging from o fragments to large sections. The UCM, formed by the nasal skeleton and the medial orbital rims, is subdivided into medial and lateral subregions Fig.
The medial or central part consists of the paired nasal bones.
The nasal bones are interposed above the nasal mzc between the frontonasal maxillary processes that form the nasal sidewalls and medial orbital rims conjointly. The nasal septum encompasses three components: In loose accordance with the height of the vomer and the perpendicular plate, the entire septal structure is arbitrarily subdivided along its vertical fracturws into two halves, the upper and lower septum.
Unilateral or bilateral fractures of the nasal skeleton can be recorded by specifying the involved UCM subdivisions. UCM, upper central midface: The division line between UCM and ICM coincides with the demarcation between the medial and the inferior orbital rim in the inferomedial quadrant.
In addition to nasal fracture components naso-orbital-ethmoid NOE fracture entities typically involve the internal orbit, the lacrimal bone, and ethmoid. To detail the extent and fragmentation in the overall or en bloc NOE fracture pattern, 2 all concomitant structures are delineated in the level 3 graphic representations, classificatioh not only of the midface, but also in the orbit 6 documentation systems.
However, at this time i. Z, zygoma; Rl, lateral orbital rim; Ri: The ICM corresponds to the midportion of the central midface pyramid and encompasses the medial part of the inferior orbital rim, the facial classificwtion wall, and para piriform buttress.
In addition, if a fracture line follows the course of the zygomatico-maxillary suture, it can be classified as either an ICM or a zygoma fracture, or even both with respect to the predominating or all-encompassing fracture pattern Fig. Accordingly, the LCM includes the solid body of the maxilla, the maxillary tuberosity, and the upper alveolar processes of the maxilla, which enclose the factures and the roots of the upper teeth.
The nomenclature to describe the classifiation sequelae of a midfacial injury follows the same scheme as used in the level 3 system for mandibular fractures.
In the tooth numbering formula of the ADA American Dental Associationthe teeth are marked with consecutive numbers following a clockwise order beginning with the maxillary right third molar 1 and continuing to the mandibular right third molar Individual teeth or teeth groups are often acronymed: To avoid confusion, two terms used conventionally in the dental nomenclature merit clarification: Over time, the alveolar ridge of any edentulous portion in the anterior and posterior maxilla will be gradually resorbed and remodeled with subsequent reduction of height.
Illustration of maxilla edentulism and atrophy. Three stages of atrophy are defined: In the posterior maxilla, coronal computed tomographic CT scan sections are most appropriate for the evaluation of the height of the alveolar ridge relative to the extent of the maxillary sinus distance between the alveolar crest and floor of the maxillary sinus.
In the anterior maxilla, the vertical dimension of the alveolar ridge distance between the crest and the nasal floor is best assessed in sagittal CT scans. For each side, the most severe occurring atrophy is considered. Periodontal and dental hard tissue injuries are documented separately for each tooth involved by the trauma with regard to tooth loss tooth avulsion or the occurrence of tooth injuries i.
If there is suspicion for tooth injuries or loss, the nature of which cannot be further clarified e. Alveolar process fractures are documented similarly to the mandible. The exact course of the vertical fracture lines comprising the involved teeth, however—directly through the tooth sockets, through the adjacent periodontal ligaments, or the bony interdental spaces—may differ on either side of the block-shaped alveolar fragment and is not specified in detail. If an edentulous region of the alveolar process is involved, the vertical boundaries are indicated as if the teeth were there.
The horizontal fracture line may cross over the tooth apices or lie at or below their level. The palatal shelves consist of the premaxilla, the palatine processes of the maxilla, and the horizontal plate of the palatine bone. Fractures of the palate are classified into one of three categories: The pterygoid processes are regarded as self-contained anatomical regions and not as parts of the sphenoid bone. Each pterygoid process can be classified as fractured.
The zygoma and its anatomical subregions constitute the lateral midface attached to each side of the maxillary portions of the central midface pyramid in transition to the greater sphenoid wing, the frontal bone, and the temporal bone.
In the level 2 midface classification system, the zygoma and the zygomatic arch have been addressed as a single anatomic region.
The fossa of the temporomandibular joint mandibular fossa is incorporated into the temporal origin of the zygomatic arch subregion ID 1. In front of the mandibular fossa, the anterior root of the zygomatic process emerges medially from the articular tubercle.
This anterior root concurs with the anterior border of the temporal origin of the zygomatic zcm. Five articulations extending from the body of the zygoma connect to the adjacent bones Fig.
Zygomaticomaxillary complex fracture
The prolongation of the inferior orbital fissure beyond its anterior loop provides a clear demarcation between the inferior and lateral orbital surface of the zygoma Fig. The posterior limit of the zygomatic body is made up by the zygomaticotemporal suture line. The inferior limit classifciation the zygomatic body is given by the caudal bony crest traversing into the zygomaticomaxillary buttress.
The infraorbital process of the zygoma subregion ID 9 stretches between the lower border of the lateral orbital rim and the zygomaticomaxillary suture. The area frqctures the ZMC Fig.
The ZMC area incorporates the lower part of the zygomaticomaxillary suture line, which divides it vertically into a lateral zygoma part Fig.
The lateral orbital process of the zygoma is continuous with the orbital roof and blends with the zygomatic process of the frontal bone lateral orbital rim superiorly.
The zygomaticofrontal suture ZFS line labeled as subregion ID 6 conjoins these merging bony portions. The zygomaticosphenoid suture ZSS line labeled as subregion ID 7 abuts the posterior margin of the lateral orbital process of the zygoma to the anterior edge of the greater wing of the sphenoid. The description of the fracture morphology at the lateral and inferior orbital flanges of the zygoma ID 5 and 8 conforms to the precepts and nomenclature allocated to the orbital walls within the level 3 Orbital Fracture Classification.
An auxiliary pathway to assign these features is provided for the zygoma in total. As the antral walls are a principal part of the ICM, the fracture morphology features can be accessed through the ICM pull-down menus in the respective skull views.
These pull-down menus contain a list of level 2 and level 3 features. Plural fracture lines and multifragmentation within a specific sector of the circular orbital rim can be highlighted with a dark background by activating its anatomic designation e.
Zygomaticomaxillary complex fracture – Wikipedia
In routine clinical parlance, fracture patterns are addressed in a concise way for rapid communication. This is reflected in the on-going practice to wrap up central and centrolateral midface fractures into terms analogous to classic Le Fort fracture types.
A1—A5 En bloc zygoma fracture: B1—B3 En bloc zygoma fracture: As the course of the fracture lines bypasses the ZSS it is left blank. G Crack of the zygomatic process of the frontal bone superior orbital rim in conjunction with the lateral edge of anterior superior orbital wall in addition to fractures displayed in F2. H Multiple fragments of the zygomatic arch and shearing fracture of the temporal origin in addition to fracture displayed in G. I Lamellar fracture of the anterior superior orbital wall in the superolateral quadrant, a fracture line running through the piriform rim in the ICM, a unilateral naso-orbito-ethmoidal fracture through the nasal bone, the nasofrontal process, and a lamellar fracture of the medial orbital wall in addition to fractures displayed in H.
Color coding of a subregion, blue denotes the presence of a fracture without any further differentiation, yellow stands for nonfragmented, nondisplaced, orange is the equivalent for fragmented, a gray crosshatching points out a bone loss. Other entries will alter the color code in correlation to the individual scenario of the injury. The subregions can be affected in various arrangements and different formations. The shown incremental order represents a random selection and intends to chart a comparable roadmap to classify distinctive midface injuries.
Such a default configuration is an isolated en bloc zygoma fracture with single fracture lines passing through the sutures at its five anatomic articulations.
This en bloc zygoma fracture can be marked in the menu bars of the skull view, what will be responded with an intense magenta coloration of the zygoma including the complete lateral wall of the orbit as is characteristic for level 2 Fig.
There is upward and downward functionality for en bloc zygoma fractures between level 2 and level 3. By definition, the en bloc zygoma fracture does not exhibit noteworthy intermediate fragments. Therefore, displacement of the monobloc is the only recordable morphology feature in the skull-view menu bar. An alternative pathway to outline the en bloc zygoma fracture prototype is to select the subregions separately. The graphical scheme of such an assembly will have a different look and color scheme Fig.