The details on this page help your documents to be easily found.pptx

The details on this page help your documents to be easily found

1. The zygomatic complex refers to the malar (cheek) eminence and its four bony articulations the frontal, maxillary, temporal, and sphenoid bone zygomatic complex fracture refers to a fracture that disrupts the zygomatic bone and at least three of its four major articulations, leading to displacement of the zygoma from its normal position in the facial skeleton Zygoma is the second most frequently fractured bone

2. Importance of the Zygoma The zygomatic bone (cheekbone) gives the prominence of the cheek and contributes to facial aesthetics. It forms part of the orbit, maxillary sinus wall, and zygomatic arch, playing a vital role in: Protection of the eye Attachment for muscles of mastication and facial expression Maintenance of facial width and contour Because of its prominence and exposed position, it is prone to trauma

3. Common causes Road traffic accidents (RTAs) – leading cause in most regions. Assaults (fist injuries, blunt trauma). Falls ( especially in elderly individuals). Sports injuries (contact sports)

4. History The zygomatic fractures are typically diagnosed by history and physical examination. The nature, force, and direction of the injuring blow should be determined from the patient and any witnesses A direct lateral blow as in an assault, often results in an isolated zygomatic arch or an inferomedially displaced zygomatic complex fracture A frontal blow usually produces a posteriorly and inferiorly displaced fracture.

5. clinical findings in zygomatic complex fracture Swelling of cheek Flattening of cheek Anaesthesia of cheek, temple, upper teeth and gingiva Periorbital haematoma Sub-conjunctival haemorrhage Tenderness over orbital rim and frontozygomatic suture Step deformity of infraorbital margin Palpable separation at frontozygomatic suture Ecchymosis and tenderness intra-orally over zygomatic buttress Limitation of ocular movement Diplopia Trismus When the arch is medially displaced.

6. . Eva] uation of the eye includes documentation of visual acuity, pupillary response to light, fundoscopic examination, ocular movement, and globe position. Limitation of motion of the extraocular muscles, diplopia, and enophthalmos may be noted if significant fractures of the orbital floor or medial or lateral walls are present. Lack of pupillary response and ptosis are present if crania] nerve III has been injured. ] nju ries to the optic nerve, hyphema , injury to the globe, retro orbital hemorrhage, retinal detachment, and disruption of the lacrimal ducts may also be present

7. Radiographic Evaluation CT-scan is the gold standard for radiographic evaluation of zygomatic fractures. Coronal views are helpful in the evaluation of orbital floor fractures , Soft tissue windows, in the coronal plane, are useful to evaluate the extraocular muscles and to evaluate for herniation of orbital tissues into the maxillary sinus

8. Plain Radiographs Waters'View The single best radiograph for evaluation of zygomatic complex fractures is Waters' view. It is a posteroanterior projection with the head positioned at a 27-degree angle to the vertical and the chin resting on the cassette.

9. Caldwell's View is a posteroanterior projection with the face at a IS-degree angle to the cassette. This study is helpful in the evaluation of rotation (around a horizontal axis)

10. Submentovertex View The submentovertex (jug-handle ) view is directed from the submandibular region to the vertex of the skull. It is helpful in the evaluation of the zygomatic arch and malar projection

11. Classification: Knight & North The Knight and North classification (1961) categorizes zygomatic fractures by displacement pattern into six groups : • Group I: No significant displacement ( undisplaced ) • Group II: Isolated zygomatic arch fracture • Group III: Lateral rotation of the zygoma • Group IV: Medial rotation of the zygoma • Group V: Depression (posterior displacement) of the zygoma • Group VI: Comminuted fracture of the zygoma

12. Classification: Rowe & Killey The Rowe and Killey system (1968) focuses on rotational deformity and post-reduction stability . It defines seven types: • Type 1: Non-displaced • Type 2: Zygomatic arch only (no lateral wall/orbital rim involvement) • Type 3: Rotation about the vertical axis (A: medial rotation, B: lateral rotation) • Type 4: Rotation about the longitudinal (horizontal) axis (A: medial, B: lateral) • Type 5: Simple displacement without major rotation (A: medial, B: lateral, C: posterior, D: inferior) • Type 6: Isolated infraorbital rim fracture (no tetrapod involvement) • Type 7: Complex (e.g. comminuted tetrapod) . Rowe– Killey classification is helpful in predicting reduction stability, as rotational injuries (Types 3–4) may be less stable after closed reduction

13. Classification: Zingg The Zingg classification (1992) divides ZMC fractures into three types : • Type A (Partial/Isolated): Involves only one ZMC component (A1: arch, A2: lateral wall, A3: infraorbital rim) Type B (Complete Tetrapod): All four articulations are fractured, but the zygomatic body remains in large pieces (no comminution) . • Type C (Comminuted Tetrapod): All four articulations are disrupted and the zygomatic bone itself is comminuted (multiple fragments) . Type A fractures are relatively uncommon; Types B and C account for the majority of ZMC injuries. This scheme is widely used in research, as it neatly categorizes injuries by severity and need for surgery

14. 1-Existing Lacerations The use of existing lacerations should be considered in facial fractures where soft tissue lacerations would provide direct access to the fracture site. If necessary, existing lacerations can be extended to attain enough access to the fracture. However, it is advisable to place the additional incisions along the relaxed skin tension lines (RSTLs).

15. Treatment Treatment of zygomatic fractures must be based on a complete preoperative evaluation. Management of zygomatic complex and zygomatic arch fractures depends on the degree of displacement and the resultant esthetic and functional deficits.

16. Zygomatic Arch Fractures Nondisplaced and minimally displaced zygomatic arch fractures may require no surgical correction. The standard Treatment for treatment of zygomatic arch fractures, first described by Gillies , can also be used to reduce zygomatic complex fractures. A temporal incision (2 cm in length) is made behind the hairline. The dissection continues through the subcutaneous and superficial temporal fascia down to the glistening white deep temporal fascia.The temporal fascia is incised horizontally to expose the temporalis muscle. Rowe zygomatic elevator, is inserted deep to the fascia, underneath the temporal surface of the zygoma . The elevator must pass between the deep temporal fascia and temporalismuscle or it will be lateral to the arch.The bone should be elevated in an outward and forward direction, with care taken not to put force on the temporal bone. The arch should be palpated at all times as a guide to proper reduction. The wound is closed in layers. Open reduction with internal fixation is seldom necessary for treatment of isolated zygomatic arch fractures.

17. Surgical Approach to the Zygomaticomaxillary Buttress. After a throat pack is placed and local anesthesia infiltrated, an incision is made in the maxillary vestibule 3 to 5 mm above the mucogingival junction. The incision extends from the canine area to the first or second molar region. The use of electrocautery may reduce bleeding. The periosteal incision is made, and a mucoperiosteal flap is elevated to expose the infraorbital nerve, piriform rim, and zygomaticomaxillary buttress

18. Surgical Approach to the Zygomaticofrontal Buttress. Access and exposure for open reduction of the zygomaticofrontal buttress can be achieved through a supratarsal fold or lateral eyebrow incision. If present, a preexisting laceration may be used for exposure of this region. The supratarsal fold incision for approach to the lateral orbit. The incision is placed in a skinfold parallel to the superior palpebral sulcus above the tarsal plate. It is placed approximately 10 to 14 mm above the margin of the upper eyelid. Blunt dissection parallel to the orbicularis oculi muscle fibers separates them and exposes the lateral orbital rim. A vertical periosteal incision is made, and subperiosteal dissection will expose the fracture. The incision provides access to the frontozygomatic suture and results in a less noticeable scar. A lateral brow incision is performed by first palpating the frontozygomatic suture.

19. For more complex injuries that may require exposure of all three anterior buttresses, the zygoma ticofrontal fracture may be first stabilized temporarily with an interosseous wire.28,31This is followed by fixation of the zygomaticomaxillary fracture and the infraorbital rim if indi cated . The temporary wire at the zygomaticofrontal fracture

20. Internal Fixation Internal Fixation Historically, many methods have been used for stabilization of zygomatic complex fractures. These have included antral packing, percutaneous wire fixation, and wire osteosynthesis . It is now accepted that miniplate or microplate fixation provides the best results and minimal complications. Controversy exists regarding the best location for internal fixation and the number and type of plates required. Multiple studies have tried to characterize the forces placed on the zygomatic complex and the amount of fixation required to achieve“stability . These forces include the masseter and temporalis muscles and fascia and soft tissue contracture, which cause rotational movements in multipleaxes around the zygomatic buttresses

21. Internal Fixation of the Zygomaticomaxillary Buttress The zygomaticomaxillary buttress provides an ideal location for internal fixation for middle- and high energy fractures. Anatomic reduction of this fracture assists in restoring malar projection, but is difficult if the buttress is comminuted. The overlying soft tissue is thick, and plate palpability is not a concern. Therefore, this fracture should be stabilized with 1.5 or 2.0 plates

22. Sequence of Internal Fixation For middle-energy injuries with exposure of all three anterior buttresses,The zygomaticofrontal fracture may be stabilized temporarily with an interosseous wire. This is followed by fixation of the zygomaticomaxillary fracture and the infraorbital rim. The temporary wire at the zygomaticofrontal fracture is replaced with a plate. The orbital floor is reconstructed after the zygoma has been restored to its correct three-dimensional position. In high-energy fractures, the zygomatic arch should be reconstructed first.

23. Internal Fixation of the Zygomaticofrontal Buttress . The zygomaticofrontal buttress contains excellent bone for fixation and can accommodate a 2.0 plate. The reduction and fixation of this fracture will reestablish the vertical height of the zygomatic complex. However, because of its narrow interface, this buttress may not be as helpful in evaluating reduction of a rotated fracture. The thickness of the soft tissue overlying this region is variable. In some instances it may be quite thin and a large plate may be palpable. If stable fixation can be achieved at other sites, a smaller platemay be used.

24. Internal Fixation of the Infraorbital Rim Unlike the zygomaticofrontal buttress, the infraorbital rim has poor quality bone for internal fixation.Additionally , the lower eyelid skin is quite thin, and large plates are easily palpable. Despite these concerns, fixation of this site is required to define the orbital volume and facial width. The infraorbital rim is typically displaced posteriorly and inferiorly.The fracture should be mobilized anteriorly and superiorly and stabilized. Typically a 1.0 or 1.5 microplate is used to stabilize the infraorbital rim.

25. Internal Fixation of the Zygomatic Arch Internal fixation of the zygomatic arch is required for high-energy fractures that demonstrate comminution and lateral displacement. Restoration of this sagittal buttress assists in restoring facial projection and facial width. width.When exposed, the zygomatic arch is often reduced and stabilized first in the sequence of repair ofhigh -energy injuries . Caution must be used in restoring a “straight” arch and not a curved” arch, which will decrease facial projection. This fracture typically requires a large plate to resist deformational forces

26. Postoperative Care Zygomatic complex fractures violate the maxillary sinus. For this reason, periorperative antibiotics and decongestants are recommended particularly if a transoral approach is used or an implant placed. Ampicillin, amoxicillin, clindamycin , or cephalosporin may be used,decongestant such as pseudoephedrine may also be indicated. Incisions are observed carefully for signs of infection, and the eye is examined to document visual acuity and to rule out complications such as corneal abrasion . Postoperative imaging should be obtained to document reduction of the fracture and orbital reconstruction .

27. COMPLICATIONS OF ZYGOMATIC COMPLEX FRACTURES

28. Infraorbital Paresthesia The incidence of sensory alterations of the infraorbital nerve after zygomatic trauma ranges from 18% to 83 %. nondisplaced midfacial frac tures had post-traumatic infraorbital nerve impairment with a mean recovery time of 4 weeks. In displaced midfacial fractures, (90 %) had altered sensation within the infraorbital nerve distribution with a mean recovery time of 13 weeks. Incomplete recovery was frequently associated with intraoperative evidence of direct nerve injury . The authors support early open reduction and internal fixa tion to improve recovery of post-traumatic nerve dysfunction.

29. Malunion and Asymmetry Inadequate reduction or stabilization of zygomatic fractures may result in malunion or asymmetry,Poor malar projection is the result of uncorrected inferior and posterior rotation of the zygoma,Increased facial width Malunion that is recognized up to 6 weeks after injury may be corrected using routine zygomatic reduction techniques. Correction of mild late deformities includes autogenous onlay grafts or placement of alloplastic implants such as porous

30. Enophthalmos Enophthalmos is one of the most troubling complications after orbitozygomatic fractures. An increase in orbital vol ume is the most common etiology Clinically, poor alignment of the orbital rim may significantly increase the orbital vol ume and result in enophthalmos . Orbital floor blow-out fracture also may result in enophthalmos by increasing the orbital volume Late repair of enophthalmos is technically challenging. Wide access with osteotomy of the zygoma , repositioning, and grafting is usually required. Redraping of the periorbital soft tissue including a canthopexy may be required

31. Diplopia Diplopia is a common sequela of midfacial fractures. The principal causes of diplopia include edema and hematoma, entrapment of the extraocular muscles and orbital tissue, and injury to cranial nerve III, IV, or VI, post-traumatic fibrosis of the extraocular muscles in response to injury Axial and coronal CT scans and ophthalmologic consultation are recommended to assist in evaluation.33.92 Diplopia related to edema, hematoma, or neurogenic causes may resolve without intervention. Diplopia resulting from entrapment requires exploration and reduction of herniated orbital tissue Persistent diplopia that does not resolve may require treatment by an ophthalmologist. The condition may respond to exercise or surgery.

32. Traumatic Hyphema Trauma to the eye may result in bleeding into the anter ior chamber-the area between the clear cornea and the colored iris Ophthalmology consultation is recommended. Goals of treatment include prevention of rebleeding , which may occur in 5% to 30% of patients, and maintenance of normal ocular tension Management of hyphema consists of supportive therapy including elevation of the head of the bed and patching of the injured eye. Medical management includes topical cycloplegics , corticosteroids, and beta blockers Rarely, surgical intervention by the ophthalmologist is required. Repair of fractures may be delayed.

33. Retrobulbar hemorrhage is a rare but severe compli cation that may be the result of either the initial injury or the operative correction. Disruption of the retinal circulation may lead to irreversible ischemia and permanent blindness . reported a 0.03% incidence of postoperative retrobulbar hemorrhage with visual loss. An emergent ophthalmologic consultation is necessary; however, decompression with lateral canthotomy and cantholysis should not be delayed

34. Patients with zygomatic fractures commonly present acutely with a complaint of trismus . The most likely cause is impingement of the zygomatic body on the coronoid process of the mandible. If the zygoma is improperly reduced, zygomatic osteotomy and repositioning may be necessary to restore unrestricted motion of the mandible .