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Edit Comment Close Premium member Presentation Transcript ZYGOMATICO- MAXILLARY COMPLEX FRACTURE : ZYGOMATICO- MAXILLARY COMPLEX FRACTURE Moderator: Dr. Syed Zakaullah Presenter: Dr.Shahid KhanPowerPoint Presentation: INFRASTRUCTURE: Introduction Etiology Surgical Anatomy Function of zygomatic bone Mechanism of zygomatic fracture Terminology and fracture pattern Classifications Diagnosis of ZMC fractures Clinical examination Signs and symptoms. Radiologic examinationPowerPoint Presentation: Treatment of ZMC fractures. Surgical approaches Reduction techniques Fixation techniques Reconstruction with grafting. Orbital Reconstruction Pediatric zygomatic complex fractures. Endoscopically Assisted Zygomatic Fracture Reduction Complications Conclusion ReferencesINTRODUCTION: INTRODUCTION Zygomatic fractures are common facial injuries. Second in frequency after nasal fractures. The high incidence of zygoma fractures probably relates to the prominent position of zygoma within the facial skeleton.PowerPoint Presentation: The incidence, cause, age, and sex predilection of zygomatic injuries vary, depending largely on the Social, Economical, Political and Educational Status of the population Male : Female – 4:1 Age - Second and Third decades of life. Bilateral fractures –less than 4%in 2067 cases (Ellis et al) ZMCETIOLOGY:: ETIOLOGY: MOTOR VEHICLE ACCIDENT SPORTS INJURY ASSAULT PATHOLOGICAL FRACTURESURGICAL ANATOMY: SURGICAL ANATOMY It is the major buttress of facial skeleton and principal structure of the lateral midface. Roughly quadrilateral in shape with an outer convex & inner concave surface. It is a Stabilizing bridge having Temporal, Orbital, Maxillary and Frontal Processes. It articulates with 4 bones : the Frontal, Sphenoid, Maxilla and Temporal.PowerPoint Presentation: MUSCLES: Temporalis muscle passes beneath the arch. Temporal fascia also attaches along the arch Levator labii superioris muscle originates just above the infraorbital rim. Zygomatic major and minor origin from the anterior face of the malar eminence. Masseter muscle across the inferior surface of the zygomatic arch and zygomatic buttress. NERVES TRAVERSING : Zygomaticofacial nerve . Zygomaticotemporal branch. Infraorbital nerve enters .PowerPoint Presentation: FUNCTIONS OF THE ZYGOMATIC BONE : To protect the globe of the eye. To give origin to the masseter muscle. To transmit part of the masticatory forces to the cranium. To absorb forces of an impact before it reaches brain.PowerPoint Presentation: Direct blow – Malar eminence. Violent blows – Contra lateral mid-face. causes a fracture dislocation of the zygoma by reciprocal transfer of forces from the opposite side of the facial skeleton. MECHANISM OF ZYGOMATIC INJURY:PowerPoint Presentation: Zygomatic or malar fracture are the terms commonly used to described fractures that involve the lateral one third of the middle face. Other names for this fracture are: Zygomatico-maxillary complex. Zygomatico-maxillary compound. Zygomatico orbital. Zygomatic complex. Malar. Trimalar. Tripod.TERMINOLOGY & FRACTUE PATTERN: TERMINOLOGY & FRACTUE PATTERN “The malar bone represents a strong bone on fragile supports and it is for this reason that, though the body of the bone is rarely broken, the four processes fontal, maxillary and zygomatic are frequent sites of fracture.” - H.D. Gillies, T.P.Kilner and D.Stone, 1927 The fracture pattern depends on direction & magnitude of the force. Three lines of fractures extend from the inferior orbital fissure in an anteromedial, a superolateral, and an inferior direction.PowerPoint Presentation: Common fracture pattern in zygoma 1.One fracture line extends from the inferior orbital fissure anteriomedialy along the orbital floor & towards infraorbital rim A second line of fracture from the inferior orbital fissure runs inferiorly through the posterior (infratemporal) aspect of the maxilla and joins the fracture from the anterior aspect of the maxilla under zygomaticomaxillary buttress.PowerPoint Presentation: The third line of the fracture extends superiorly from the inferior orbital fissure along the lateral orbital wall posteriorly to the rim usually separating the zygomaticosphenoid suture. This 3 fracture lines exist with arch fracture.PowerPoint Presentation: CLASSIFICATION…PowerPoint Presentation: SCHIELDERUP (1950) : TYPE 1 : Fractured zygoma hinged on maxillary & frontal attachment. TYPE 2 : Fractured and hinged on maxillary attachment TYPE 3 : Fractured and hinged on frontal attachment TYPE 4 : Fractured and detached enbloc. TYPE 5 : Comminuted fracture. KNIGHT AND NORTH’S CLASSIFICATION : In 1961 Group I : Undisplaced fractures. Group II : Arch fractures. Group III : Unrotated body fractures. Group IV : Medially rotated body fractures. Group V : Laterally rotated body fractures. Group VI : Complex fractures.PowerPoint Presentation: Rowe & Killey (1968) Type I : No significant displacement Type II : Fracture of the zygomatic arch Type III : Rotation around vertical axis - Inward displacement of orbital rim - Outward displacement of orbital rim Type IV : Rotation around longitudinal axis - Medial displacement of frontal process - Lateral displacement of frontal process Type V : Displacement of the complex en bloc - Medial - Inferior - lateral (Rare) Type VI : Displacement of orbitoantral partition - Inferiorly - Superiorly Type VII : Displacement of orbital rim segments Type VIII : Complex comminuted fractures.PowerPoint Presentation: Type I : no significant displacementPowerPoint Presentation: Type II . Fracture of the zygomatic archPowerPoint Presentation: Outward Displacement Inward Displacement Type III. Rotation around vertical axisPowerPoint Presentation: Type IV. Rotation around longitudinal axisPowerPoint Presentation: Type V. Displacement of the complex en blocPowerPoint Presentation: Type VI. Displacement of orbitoantral partitionPowerPoint Presentation: Type VII. Displacement of orbital rim segmentsPowerPoint Presentation: Type VIII. Complex comminuted fracturesMANSON AND COLLEAGUES (1990) : : MANSON AND COLLEAGUES (1990) : Based on amount of energy dissipated & findings in C.T. Scan- a. High energy fractures. b.Moderate energy fractures. c. Low energy fractures. MARKUS ZING (1992) Type A : Incomplete zygomatic fracture. Type B : Complete monofragment zygomatic fracture (tetradpod fracture). Type C : Multifragment zygomatic fracture.PowerPoint Presentation: ROWE’S & WILLIAM’S CLASSIFICATION : 1) Fractures stable after elevation a. Arch only (medially displaced) b. Rotation around the vertical axis. Medially Laterally 2) Fracture unstable after elevation . a. Arch only (inferiorly displaced). b. Rotation around the horizontal axis. Medially Laterally c. Dislocations enblock Inferior Medially Posterio-laterally. d. Comminuted fracture.PowerPoint Presentation: Group A : Stable fracture – Showing minimal or no displacement and requires no intervention. Group B : Unstable fracture – With great displacement and distruption at the frontozygomatic suture and comminuted fracture. Requires reduction as well as fixation. Group C : Stable fracture – Other types of zygomatic fractures, which requires reduction, but no fixation. Fractures of the zygomatic arch alone Minimum or no displacement. V type in fracture. Comminuted fracture. LARSEN &THOMSEN CLASSIFICATIONPowerPoint Presentation: MALAR CLASSIFICATION TYPE 1 : Undisplaced fracture. TYPE 2 : Arch fracture only. TYPE 3 : Tripod malar fracture ( FZ intact ). TYPE 4 : Tripod malar fracture (FZ distracted ). TYPE 5 : Pure blow-out fracture.. TYPE 6 : Orbital rim fracture. TYPE 7 : Comminuted and other fractures SPIESSEL AND SCHROLL’S CLASSIFICATION : TYPE 1 : Isolated zygomatic arch fracture TYPE 2 : Fracture with no significant displacement TYPE 3 : Partially displaced medially TYPE 4 : Totally displaced medially TYPE 5 : Those with dorsal displacement TYPE 6 : Those with inferior displacement TYPE 7 : Comminuted and other fracturesPowerPoint Presentation: DIAGNOSIS OF ZMC FRACTURE Based on clinical examination, radiologic examination , history -a. suggestion of possibility of fracture b. nature. c. direction. d. force of blow.PowerPoint Presentation: INSPECTION: performed from frontal, lateral, superior and inferior vantages symmetry pupillary levels presence of orbital edema subconjunctival ecchymosis anterior and lateral projection of zygomatic bodies intraoral examination Clinical ExaminationPowerPoint Presentation: PALPATION: infraorbital rims lateral orbital rims body of zygoma zygomatic arch zygomatic buttress of the maxilla are palpated.CLINICAL EXAMINATION: CLINICAL EXAMINATION It should be performed from the frontal, lateral, superior and inferior vantages Note symmetry, pupillary levels and presence of orbital edema and subconjuctival ecchymosis and anterior and lateral projection of zygomatic bodies. pupillary levelsPowerPoint Presentation: The most useful method of evaluating the position of the body of the zygoma is from the superior view. Intraoral examination to evaluate buccal echymosis in the sup. Buccal sulcus . Palpation of the infraorbital. rim, frontozygomatico suture, body of the zygoma and arch.PowerPoint Presentation: The presence and magnitude of severity of these greatly depends on the extent and type of zygomatic injury. PERIORBITAL ECCHYMOSIS AND EDEMA : edema and bleeding loose connective tissues of eyelids and periorbital areas. SIGNS AND SYMPTOMSPowerPoint Presentation: Ecchymosis : inferior lid and infraorbital area. FLATENING OF THE MALAR PROMINENCE : characteristic sign and striking feature. FLATTENING OVER THE ZYGOMATIC ARCH: loss of normal convex curvature in temporal area.PAIN: Discomfort associated with attendant bruising. ECCHYMOSIS OF MAXILLARY BUCCAL SULCUS: an important sign. : PAIN: Discomfort associated with attendant bruising. ECCHYMOSIS OF MAXILLARY BUCCAL SULCUS : an important sign. DEFORMITY AT THE ZYGOMATIC BUTRESS OF MAXILLA : Intraoral palpation irregularities especially in zygomatic buttress area of maxilla.PowerPoint Presentation: DEFORMITY OF THE ORBITAL MARGIN : Displacement Gap or step deformity.PowerPoint Presentation: TRISMUS : impingement of translating coronoid process of mandible on displaced zygomatic fragments. limitation of mouth opening. CREPITATION FROM AIR EMPHYSEMA : sinus wall with tearing of lining mucosa allows air to escape into facial soft tissues. on rolling two fingers gently over the tissues produces crackling sensationPowerPoint Presentation: ABNORMAL NERVE SENSITIVITY : fracture through the orbital floor and anterior maxilla. Tearing ,shearing and compression of infraorbital nerve. Impaired sensation of infraorbital nerve Anesthesia of lower eyelid, upper lip and lateral aspect of nose.PowerPoint Presentation: EPISTAXIS: sinus mucosa Disruption. Hemorrhage into sinus.PowerPoint Presentation: SUBCONJUNCTIVAL HAEMORRHAGE & ECCHYMOSIS : accompanies hair line crack through orbital rim if periosteum is torn.PowerPoint Presentation: DISPLACEMENT OF PALPEBRAL FISSURE : Displacement of zygoma lateral palpebral ligament – depressed Causes downward slope to fissure. Dramatic visual deformity.PowerPoint Presentation: UNEQUAL PUPILLARY LEVELS : Loss of osseous support of orbital contents. Displacement of tendon’s capsule and suspensory ligament of globe. Permits depression of globe. Clinically manifested –unequal pupillary levels.PowerPoint Presentation: Separation at frontozygomatic suture: Enopthalamus: lateral and inferior displacement of the zygoma. increase in orbital volume. Herniation of orbital soft tissues. EnopthalmusPowerPoint Presentation: DIPLOPIA: blurred vision – monocular diplopia – binocular diplopia presence of entrapment of orbital contents . determined by forced duction testFORCED DUCTION TEST: FORCED DUCTION TEST Tendon of inferior rectus muscle is grasped by Small forceps. Globe is manipulated to its entire range of motion. Inability to rotate superiorly Entrapment of muscles in orbital floor.RADIOLOGICAL EVALUATION: RADIOLOGICAL EVALUATION Plain film radiography Water’s View/PNS/ Occipitomental view Caldwell’s View Submentovertex Lateral skull viewWaters’ View : Waters’ View The single best radiograph for evaluation of zygomatic complex fractures Permitting visualization of the sinuses, lateral orbits, and infraorbital rims . In patients who are unable to assume a facedown position, a reverse Waters’ projection provides similar information.PowerPoint Presentation: Caldwell’s View: It is a modify water’s view With open mouth. It is a posteroanterior projection with the face at a 15° angle to the cassette This study is helpful in the evaluation of rotation (around a horizontal axis).PowerPoint Presentation: Submentovertex View (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 & malar projection. Computed Tomography: Computed Tomography CT scan Axial and coronal images are obtained to define fracture patterns, degree of displacement & comminution to evaluate the orbital soft tissues. Axial view Coronal viewTREATMENT: TREATMENTPowerPoint Presentation: Steps in surgically treating a zygomaticomaxillary complex fracture : Prophylacitc antibiotics. Anesthesia. Clinical examination and forced duction test. Protection of the globe. Antiseptic preparation. Reduction of the fracture. Assessment of reduction. Determination of necessity for fixation. Application of fixation device. Internal orbital reconstruction. Assessment of ocular motility. Bone graft for extraorbital osseous defects. Soft tissue resuspension. Postsurgical ocular examinations.INDICATIONS FOR SURGERY: INDICATIONS FOR SURGERY To restore the normal contour of the face both for cosmetic reasons and to re-establish the skeletal protection for the globe of the eye. To correct diplopia . To remove any interference with the range of movement of the mandible . Relieve pressure on the infra-orbital nerve. Surgical intervention avoided in minimal displacement which are not causing symptoms And in elderly and a poor operative risk patient.Surgical approaches: Surgical approaches Approches for zygomatic complex -carroll-girard screw. -vestibular approach. Approches for Zygomatico-frontal region -Lateral canthotomy. -Upper eyelid approach. -Eyebrow approach. Approches for Infraorbital rim & orbital floor -Lower eyelid approaches. -Transconjuntival approach. -Subciliary approach. -Subtarsal approach.PowerPoint Presentation: Approches for Arch & Zygomaticotemporal Suture Coronal approach Approches for isolated & Zygomatic arch fracture -Gillies temporal approach.PowerPoint Presentation: Maxillary vestibular approach: The incision is usually placed approximately 3 to 5 mm superiorly to the mucogingival junction. advantages: Hidden intraoral scar. Rapid and simple Complications are few .PowerPoint Presentation: Supraorbital / Lateral eyebrow approach gain access to the lateral orbital rim. advantages: No neurovascular structures are at risk. simple and rapid access to the frontozygomatic area. Minimal scar. incision is made through skin & subcutaneous tissue. Exposure of lateral orbital rim and subperiosteal dissectionPowerPoint Presentation: Upper eyelid approach : upper blepharoplasty, upper eyelid crease, and supratarsal fold approach. approach to the superolateral orbital rim. incision -10mm superior to the upper lid margin and be 6 mm above the lateral canthus. advantage : The inconspicuous scar it creates, rendering it, one of the best approaches to the region of the superolateral orbital complex.PowerPoint Presentation: a) Infra-orbital Incision: incision is placed just over infraorbital rim, periosteum the rim should be palpated and periosteal incision should be placed 3mm inferior to rim but should not be made too far inferior to avoid injury to infraorbital nerve and vessels. Lower eyelid approaches: 2 types-PowerPoint Presentation: major disadvantage is that a visible scar. advantages : incision is simple, since it is a direct and short approach. avoids orbital septum & periorbital fat. there is almost non-existing post-operative ectropion. incision can be extended medially or laterally . it standard for inexperienced surgeons.PowerPoint Presentation: B ) SUBTARSAL APPROACH: Employed for access to the infraorbital rim and orbital floor. Incision-is placed at the level of the inferior margin of lower tarsus. Starts – skin with orbicularis oculli muscle Stops –at orbital septum. Advantages : Relatively easy. Scar is imperceptible. Minimal complications.PowerPoint Presentation: Sub- Cilliary Incision: infra- ciliary incision or “blepheroplaasty incision”. incision is made approx.2mm inferior to the gray line of lower eyelid along the entire length of lid. Advantage: scar is least visible. Disadvantages : procedure is technically sensitive and difficult. higher risk of post-surgical ectropion and if a subcutaneous dissection is used, adaptation of skin to the muscle may not be smooth.PowerPoint Presentation: Subcutaneous dissection of skin, leaving pretarsal portion of orbicularis muscle Dissection between orbicularis oculi muscle and orbital septum Subperiosteal dissection of anterior maxilla and orbital floor. Note that the periosteal elevator entering the orbit Lower eyelid suspensory suture placed at completion of surgery. Taking care to engage the tarsal plate IncisionPowerPoint Presentation: Transconjunctival approach : Also called the inferior fornix approach, was originally described by Bourguet in 1928 . 2 basic incisions the preseptal and the retroseptal approaches. Ad.: Rapid, No skin or muscle dissection is necessary. Disadvantage : the limited access. Incision of the conjunctiva below the tarsal plate. Incision through periosteum ClosurePowerPoint Presentation: Techniques for Lateral Canthotomy: If exposure is found to be too limited, a lateral canthotomy can be included in the incision. This is simply done by inserting one end of sharp iris scissors into lateral palpebral fissure and cutting it through horizontal direction. A trans-conjunctival incision is then connected with canthotomy.PowerPoint Presentation: Coronal approach : Excellent access to the orbits, zygomatic bodies, and zygomatic arches. It is an extermely useful incision where there is comminution of the supraorbital and lateral orbital rims, and zygomatic body and arch. The scar produced is hidden within the hairline and is therefore invisible.PowerPoint Presentation: REDUCTION TECHNIQUES :PowerPoint Presentation: Gillies Temporal approach : for reduction of both ZMC and zygomatic arch fractures. First described by Gillies and Coworkers in 1927 . Technique : Hair is shaved Vaseline gauge – external auditory meatus Incision – 2.5 cm superior to the bifurcation of the superficial temporal artery. exposure of the temporal fascia.PowerPoint Presentation: Definitive elevator: Bristow’s orthopaedic periosteal elevator Advantages: is that it allows the application of great amounts of controlled force to disimpact even the most difficult zygomatic fractures. Quick and simple -15- 20 min . Rowe zygomatic elevatorPowerPoint Presentation: Gillies Temporal ApproachPowerPoint Presentation: Buccal sulcus approach : Keen technique : Keen published an article on this technique in 1909. A 1cm incision is made in the mucobuccal fold, just beneath the zygomatic buttress of the maxilla. A heavier instrument can then be inserted behind the infratemporal surface of the zygoma. Superior, lateral, and anterior force to reduce the bone.PowerPoint Presentation: lateral coronoid approach : Quinn (1977) for isolated fractures of the arch. 3 to 4 cm intraoral incision is made along the anterior border of the ramus through mucosa and submucosa. The incision is not made to bone. blunt dissection Flat-bladed, heavy elevator is inserted into this pocket. arch is elevated.PowerPoint Presentation: Percutaneous Approach : Poswillo(1976) A very direct route to elevation of the depressed zygoma is through the skin surface of the face overlying the zygoma. The point of the hook is inserted through the soft tissues of the malar area at a point just inferior and posterior to the prominence.PowerPoint Presentation: Elevation from eyebrow approach : Advantage to this technique is that the fracture at the orbital rim is visualized directly, and fixation of the fracture at this point can be undertaken through the same incision when necessary. Disadvantage is that it is difficult to generate a large amount of force, especially in the superior direction.PowerPoint Presentation: Carroll-Girard Screw : screw placed directly into the body of the zygoma via a small transcutaneous stab incision. Other Indirect Approache.FIXATION: FIXATION Non-displaced fractures should be followed clinically without surgical intervention One or two point fixation may be adequate for stable, minimally displaced fractures Direct fixation at the site of fracture techniques for unstable, comminuted, and grossly displaced fracturesDIRECT FIXATION TECHNIQUES : DIRECT FIXATION TECHNIQUES 1) Transosseous Wiring – 0.35mm diameter stainless steel wire/fine braided stainless steel wire. Direct wiring /figer of 8 pattern For severe displaced fracture it is prefered to use micro or mini plates along with /without transosseous wiring.2) Rigid fixation-mini-plates General principle in using plates and screws in fixation of ZMC#: 2) Rigid fixation-mini-plates General principle in using plates and screws in fixation of ZMC# Use self threading bone screws Use hardware that dose not scatter postoperative CT scans. Use atleast 2 screws through the plates on each side of the fracture Avoid important anatomic structures Use thin plate in periorbital area (if possible avoid plates in this location ) Ensure stabilityINDIRECT FIXATION : INDIRECT FIXATION a) External pin fixation Zygomatico- zygomatic (transmaxillary) Naso- zygomatic Zygomatico- palatal Maxillo- zygomatic Fronto- zygomatic Cranio-zygomatic Am J Surg 92 :12,1956PowerPoint Presentation: b) Maxillary antral support To support zygomatic complex fractures To support reconstructed comminuted orbital floor. Temporary packing with penrose drains, gauze, gelfoam, silastic, antral balloonReconstruction with grafting: Reconstruction with graftingReconstruction with graft/osteotomy: Reconstruction with graft/osteotomy Orbital reconstructionPowerPoint Presentation: PEDIATRIC ZYGOMATIC COMPLEX FRACTURES Reasons for low incidence Prominence of calavarium Relative retrusions of the midface. Lack of development of the maxillary sinus. Elasticity of facial bones Treatment: Wire fixation is advocated in preference to RIF because wire placement requires much smaller incision ,less likely to injure developing tooth buds. Experimental studies have shown RIF application interferes with growth and results in facial deformity.PowerPoint Presentation: ENDOSCOPICALLY ASSISTED ZYGOMATIC FRACTURE REDUCTION AND OSTEOSYNTHESIS: Comminuted zygomatic fractures require exposure of the malar arch for correct skeletal repair. Traditionally, arch exposure is achieved by a coronal incision with possible risks of increased blood loss , alopecia , loss of sensation posterior to the incision, weakness of the frontal branch and hollowing of the temporal fossa. The orbital floor or the zygomatic arch are approached with upper buccal sulcus and preauricular incision & an endoscope.PowerPoint Presentation: Advantages: Automatic rotation of the endoscopic image into the correct orientation facilitated handling of the instruments and the arch. no complications are noticed. Scar formation is minimal. Facial nerve function is not impaired . Only disadvantage is operating time :2 -4hrs.COMPLICATIONS: COMPLICATIONS Infrorbital nerve damage. Persistent diplopia. Enophthalmos. Blindness. Retrobulbar and intraorbital hemorrhage. Maxillary sinusitis. Ankylosis of zygoma to coronoid process. Malunion of zygoma.PowerPoint Presentation: CONCLUSION : zygoma plays an important role in facial contour Disruption of zygomatic position also has great functional significance because it creates impairment of ocular & mandibular function. Therefore, for both cosmetic and functional reasons, it is imperative that zygomatic injuries be properly and fully diagnosed and adequately treate.REFERENCE: REFERENCE FONSECA – VOL 1 3 rd EDITION KILLEYS – 3 rd EDITION ROW AND WILLIAMS – VOL 1 PETER WARD BOOTH – VOL 1 COMPLICATION IN ORAL AND MAXILLOFACIAL SURGERY-KABBAN CONTEMPORARY ORAL AND MAXILLOFACIAL SURGERY,4 th EDITION-LARRY.J.PETERSON,JAMES.R.HUPP,MYRON.R.TUCKER TEXT BOOK OF ORAL AND MAXILLOFACIAL SURGERY,-NEELIMA ANIL MALIK -2 nd EDITIONPowerPoint Presentation: THANK YOU… You do not have the permission to view this presentation. In order to view it, please contact the author of the presentation.