Theme 11. Damage of zygomatic bones and nasal bones in peace-time. Classification, frequency, clinic, diagnostics, treatment. Achievements of native scientists, employees of department.

1. ACTUALITY OF THEME: fractures of the zygomatic bone and the zygomatic arc is 9,8% of fractures of the upper jaw, and fractures of the nose consists 12,5%. Clear knowledge of clinical displays fractures of this areas will help a doctor to set a faithful diagnosis and avoid flagrant errors.

2.CONCRETE AIMS: 1.1. To analyze statistics of zygomatic and nasal bones fractures in peace-time. 1.2. To explain pathogeny of fractures of zygomatic and nasal bones in peace-time. 1.3.To propose methods of diagnostics of patients with the zygomatic and nasal bones fractures in peace-time. 1.4. To classify the fractures of zygomatic and nasal bones in peace-time. 1.5. To interpret complications, that appear when the zygomatic and nasal bones fracture occurs. 1.6. To analyze the influence of zygomatic and nasal bones fractures on central nervous system. 1.7. To propose the plan of treatment of patients with the zygomatic and nasal bones fractures in peace-time.

3. BASIC KNOWLEDGE, ABILITIES, SKILLS, WHICH are NECESSARY FOR STUDY THEMES (intradisciplinary integration).

P revious disciplines	Mastered skills
1.Normal anatomy.	To know the structure of the upper jaw and the anatomy of muscles which are attached to the maxilla, zygomatic bones.
2.General surgery.	Plan of inspection of patient with a traumatic damage.
3. Rontgenology	Character of roentgenologic picture at zygomatic bone, arc and nasal bones fractures.
4. Neurology.	Clinical displays of nervous diseases at the fractures of zygomatic and nasal bones.
5. Topographical anatomy and operative surgery.	To interpret the topographical anatomy of maxillofacial area. Principles of operative accesses to the different parts of maxillofacial area.
6. Regenerative plastic surgery of maxillofacial area.	Consequences of traumatic damages of maxillofacial area in peace-time, measures of prevention of complications and victims inability.
7. Surgical stomatology and maxillofacial surgery.	Basic questions of combined trauma, connection of organs and systems of maxillofacial area.

TASKs FOR INDividual WORK DURING PREPARATION TO Lesson.

4.1. List of basic terms, parameters, characteristic, which a student must master at preparation to lesson:

Term	Definition
1. Fracture.	This is disorder of integrity of bone.
2. Main anatomical location types of zygomatic bones and nasal bones.	Open and close. With dislocation and without dislocation.

4.2.Theoretical questions to lesson: 1. The peculiarities of the nasal bones structure. 2. The clinical displays of nasal bones fractures. 3. How to stop nasal bleeding when the fracture of nasal bones? 4. Diagnostics of nasal bones fractures. 5. Surgical treatment of nasal bones fractures. 6. Mistakes and complications during and after application of surgical treatment of upper jaw non-bullet fractures. 7. Peculiarities of zygoma and arc structure. 8. Clinical displays of zygomatic bone and arc fractures. 9. Diagnostics of zygomatic bone and arc fractures. 10. Conservative methods of treatment of zygomatic bone and arc fractures. 11. Surgical methods of treatment of zygoma and arc.

4.3. Practical works (task) which are executed on lesson: 1.To master a method of inspections of patient with a zygomatic and nasal bones fracture. 2. Additional methods of inspection of patient with a zygomatic and nasal bones fracture. 3. To conduct a treatment of patient with the upper jaw fracture. 4. To fill the ambulatory medical card of patient with the zygomatic and nasal bone fracture. 5. To formulate a prognosis of treatment of patient with the zygomatic and nasal bone fracture. 6. Rehabilitation of patient after the maxilla fracture.

5. TABLE OF CONTENTS OF THEME:

Fractures of the zygomatic complex

Classification

The zygomatic bone is intimately associated with the maxilla, frontal and temporal bones, and as they are usually involved when a zygomatic bone fracture occurs it is more accurate to refer to such injuries as «zygomatic complex fractures». Many texts and clinical departments refer to these injuries as «malar complex fractures», malar being the generic term pertaining to the cheek.

The zygomatic bone usually fractures in the region of the frontozygomatic, the zygomatico-temporal and the zygomatico-maxillary sutures. It is unusual for the zygomatic bone itself to be fractured, but occasionally it may be split across and when there has been extreme violence the bone may even be comminuted. The arch of the zygoma may be fractured in isolation from the rest of the bone.

A classification of fractures of the zygomatic complex is most usefully based on the extent of involvement of the structures within the orbit. All fractures of the body of the zygomatic complex must involve the orbit but the importance of that involvement depends on the degree and direction of displacement.

Downward displacement with separation at the frontozygomatic suture means that the lateral attachment of the suspensory ligament of the eye to Whitnall’s tubercle is also displaced downwards with alteration of the visual axis.

Inward and posterior displacement does not produce this effect, but these fractures may also interfere with eye movement because of entrapment of orbital adnexae in the orbital floor.

Rarely the body of the zygomatic complex (usually on both sides) is displaced outwards following a central blow to the face with impac-tion of the central block of the mid-face.

The fractures of the zygomatic complex may be classified, therefore, as follows.

Fractures of the body of the zygomatic complex involving the orbit:

1. Minimal or no displacement.

2. Inward and downward displacement.

3. Inward and posterior displacement.

4. Outward displacement.

5. Comminution of the complex as a whole.

           Fractures of the zygomatic arch alone not involving the orbit:

1. Minimal or no displacement.

2. V-type in-fracture.

3. Comminuted.

       An understanding of the nature of the displacement of the zygomatic complex is of value when planning the disimpaction of the fracture and in evaluating the probable stability of the fragments after reduction.

Rowe (1985) has pointed out that when the zygomatic complex is displaced around a vertical axis running through the frontozygomatic suture and first molar tooth, it tends to be stable after simple reduction. However, if displacement occurs round a horizontal axis running through the infra-orbital foramen and the zygomatic arch, simple reduction of the fracture is unstable. It will readily be appreciated that in the latter group of fractures there is separation at the frontozygomatic suture. Fractures of the zygomatic complex which are either comminuted or in which the periosteum of the frontozygomatic suture is torn are inherently unstable after simple reduction and therefore need direct fixation by surgical intervention.

Signs and symptoms

The signs and symptoms of a fracture of the zygomatic bone are closely related to the surgical anatomy of the part.

       Flattening of the cheek

When the zygomatic bone is fractured as a block near its principal three suture lines, it forms a tripod most often displaced inwards to a greater or lesser extent. There may be minimal displacement or an obvious unsightly flattening of the cheek on that side. Tenderness is noted at the fracture lines, particularly over the frontozygo-matic suture, and an obvious step may be present at the infra-orbital margin.

The amount of depression may be masked if the patient normally has full cheeks; on the other hand, certain ethnic types, such as the Slavonic race, who normally have prominent cheek bones, may exhibit marked flattening of the face with only moderate inward displacement of the underlying skeleton.

The physical sign of flattening of the cheek bone is best seen by viewing the patient either from above by standing behind and above the patient and comparing the two sides of the face, or by viewing the two cheek bones from below. Flattening is most obvious either immediately after the accident before the area has become oedematous, or after the swelling has subsided.

The speed with which oedema occurs varies considerably. In some thin, elderly patients, flattening may be obvious up to about an hour after the injury; on the other hand, young plump-faced individuals swell up almost immediately. It is always possible to palpate the zygoma at the point of maximum prominence of the cheek. If oedema is masking the flattening, the examiner should view the cheek prominence from above and behind the patient with each forefinger placed on the point of maximum prominence on each side. The relative position of the tips of the two fingers can then be readily compared with an unaffected contour such as the mid-point of the forehead or tip of the nose. Even with marked oedema this manoeuvre enables an assessment to be made of the degree of flattening. Most of the overlying swelling subsides in about a week, but the full extent of the flattening is not apparent until all oedema has completely disappeared, which takes up to three weeks.

Haemorrhage

       Circumorbital ecchymosis occurs in most cases of zygomatic fracture as well as with Le Fort II and III fractures. Fractures which involve the orbital walls tend to be accompanied by sub-conjunctival haemorrhage, but the absence of this type of haemorrhage in a patient with a 'black eye' does not exclude the presence of a fracture. The pattern of haemorrhage around the orbit after injury is so variable that it has little diagnostic value as regards underlying bony injury. Soil (1977) defines the following types of orbital haemorrhage:

a. Haemorrhage anterior to the orbital septum causing lid ecchymosis.

b. Subperiosteal haematoma.

c. Haemorrhage posterior to the orbital septum including subconjunctival haemorrhage.

d. Haemorrhage within the muscle cone.

e. Intracranial haemorrhage which spreads to the orbit via the superior orbital fissure or optic foramen.

       Ecchymosis of the eyelids alone is usually caused by soft-tissue injury. The extravasated blood is not confined by the orbital septum and spreads wherever the skin is loose, even on occasions across the bridge of the nose.

       Fractures of the orbital walls may be accompanied by Subperiosteal haemorrhage and if the periorbita is damaged, as it usually is, this may extend into the conjunctiva. Haemorrhage posterior to the orbital septum may be present after soft-tissue or bony injury. It is sharply limited by the septum and tarsal plate and usually extends into the conjunctiva.

       Haemorrhage within the muscle cone may have more serious consequences. Retrobulbar haemorrhage may rarely occur either as a result of a zygomatic fracture or more usually following surgical reduction (Ord, 1981). If the haemorrhage causes sufficient rise in pressure within the intraconal space, it produces the classical signs of pain, proptosis, a dilating pupil, ophthalmoplegia and decreasing visual acuity. Blindness may follow in the absence of decompression, and is thought to be caused by ischaemia of a critical zone of the optic nerve head following occlusion or spasm of the short posterior ciliary arteries. Occasionally extraconal haemorrhage may produce a similar clinical picture, explaining the rare cases of blindness after cosmetic blepharoplasty. Again, it is suggested that spasm of the important group of short posterior ciliary arteries is the cause (Ord et ai, 1986).

    When the zygomatic bone is displaced into the maxillary sinus in the region of the zygomatico-maxillary suture, the outer wall of the antrum is comminuted and the antrum fills with blood. This can be seen on X-ray examination as an opacity of the antrum, and at the time of the injury and for a short time afterwards the blood escapes from the antrum through the ostium into the nose and produces a unilateral epistaxis.

    Nerve damage

    Most fractures of the body of the zygomatic complex involve the infra-orbital nerve leading to either a neuropraxia or neurotmesis. The zygomatic nerve is also frequently damaged causing anaesthesia or paraesthesia within the distribution of the zygomatico-facial and zygomatico-temporal branches. The patient may, therefore, exhibit anaesthesia of the temple, check, one side of the upper lip and the side of the nose. The length of anaesthesia depends on the degree of damage to the nerve, but recovery of sensation usually occurs within 6 to 9 months at the most.

    Interference with mandibular excursion

    When the zygomatic complex is displaced inwards, it may impinge on the eoronoid process of the mandible and interfere with mandibular movements. If, as is usual, the mouth was closed at the time of injury, the patient may be unable fully to open the mouth. Much more rarely, if the mandible is widely open at the time of injury, the zygomatic bone may be driven in to such an extent that it is impossible for the patient to close the mouth. Lateral excursion and protrusion of the mandible to the fractured side is always impaired in these situations.

    Diplopia

    Diplopia is a potentially serious feature of some fractures of the zygomatic complex, occurring in approximately 10 per cent of cases (Mansfield, 1948; Barclay, 1960; Tempest, 1960).

    Diplopia is caused by interference with the action of extraocular muscles, which in most cases results from oedema and haemorrhage in and around these muscles. This type of diplopia is usually temporary but when there has been actual damage to the extraocular muscles or to their nerve supply recovery is less certain.

   Alteration of the level of the eye without interference with the extraocular muscles or their nerve supply does not itself cause diplopia, a fact which can be simply demonstrated by turning the head to one side so that one eye is lower than the other. Of course, in this situation, the visual cortex is similarly tilted. It is not unusual, however, to find a patient with one eye considerably displaced who does not complain of diplopia, but this is commonly because binocular vision has been depressed at a cortical level. For example, where telorbitism exists as a craniofacial deformity, diplopia is never a feature because of the complete absence of binocular vision at any time during growth and development. Unfortunately, when the level of the eyes is altered because of injury there is invariably alteration in the visual axes and the lines of action of the extraocular muscles are, as a result, also altered. For example, if the globe on one side is lowered, this means the inferior rectus muscle is slightly shortened and the superior rectus slightly lengthened. This indirect effect on the extraocular muscles usually leads to diplopia unless the muscles are able to compensate for the aparallelism of the visual axes.

    Alteration of the ocular level depends on the level at which the fracture occurs in the lateral wall of the orbit. The globe of the eye is supported by Lockwood's suspensory ligament, which is a condensation of the fascia within the orbit extending from a medial attachment in the region of the lacrimal bone, to a lateral insertion into Whitnall's tubercle on the lateral wall of the orbit just below the frontozygomatic suture If the fracture passes below Whitnall's tubercle, the zygomatic bone can be grossly displaced downwards without alteration in the level of the globe of the eye. However, if the fracture occurs above Whitnall's tubercle and the bone is displaced downwards, the upper lid follows it and produces a characteristic «hooding» of the globe, or pseudoptosis, a physical sign which becomes more obvious as the initial oedema subsides.

    Diplopia can be tested by holding a finger or object at least an arm's length in front of the eyes and asking the patient to report double vision as the finger is moved. Diplopia recorded closer to the patient than one arm's length may not be clinically significant. It is not, for example, significant if reading is unaffected. Diplopia should be recorded in each of the nine positions of gaze.

       Diplopia itself is measured by means of a prism bar. A Hess chart, however, is the most useful clinical tool for measuring the progress or otherwise of patients with double vision. The Hess chart records the range of movement of each individual eye. It shows which of the extraocular muscles is functioning abnormally and by repeating the examination every other day the progress of the diplopia can be monitored. Rapid improvement as shown on the Hess chart indicates that double vision was caused by temporary muscle oedema. If, however, the Hess chart remains unchanged in the first week, this implies more permanent damage, a finding which will influence decisions as regards treatment.

       Enophthalmos

       Enophthalmos is a troublesome sequel to some fractures of the zygomatic complex. This sinking inwards of the eye may itself be a cause of diplopia. Enophthalmos occurring immediately after injury is the result of an increase in the volume of the orbit due to fracture of its walls. It is made worse by herniation of fat from the orbit via defects usually in the floor or medial wall. Fat can also escape from the orbit via the inferior orbital fissure without there being evidence of bony injury in that area.

   In recent years important advances have been made in the understanding of the anatomy of the tissues supporting the globe of the eye. Koorn-neef (1977) demonstrated the presence of a network of connective tissue organized into fibrous septa within the orbital fat. Condensation of this connective tissue constitutes the suspensory ligament and also completes the cone formed by the extrinsic ocular muscles. Post-traumatic scarring of this supporting tissue can cause inward and downward displacement of the globe and contribute to late-developing enophthalmos.

   Computed tomographic scanners can be used to measure precisely the volume of the orbit and its various soft-tissue components (Bite et al., 1985; Manson et al., 1986). Manson et al. (1986) have compared the volume of injured with normal orbits in a group of patients and related their findings to a detailed anatomical investigation of the mechanisms of global support. These studies demonstrate conclusively that fat atrophy is not a significant feature in most patients with post-traumatic enophthalmos. Enophthalmos is caused either by escape of orbital fat or by an increase in the volume of the bony orbit.

   Intra-orally

   Sometimes, as the zygomatic bone is driven in, the entire maxilla is 'sprung' down without being fractured and there may be temporary gagging of the occlusion in the molar area on the fractured side. Comminution of the outer walls of the maxillary antrum may damage the anterior, middle or posterior superior dental nerves, with resulting anaesthesia of the teeth and gums.

   There is often marked ecchymosis in the upper buccal sulcus in the region of the zygo-matic buttress.

There is also tenderness on palpation over the zygomatic buttress area intra-orally, and sometimes crepitus may be felt.

       Fractures of the zygomatic arch

       Fractures of the zygomatic arch may coexist with fractures of the zygomatic bone. In such cases, the distinguishing features of the zygomatic arch fractures are obscured by the more gross physical signs associated with the zygomatic bone fractures.

  Fractures of the zygomatic arch tend to impinge on the coronoid process and so extreme interference with mandibular movements may be found in combined zygomatic bone and zygomatic arch fractures.

   The zygomatic arch may be fractured without fracturing the zygomatic bone at its frontozygomatic and zygomatico-maxillary suture lines. In such a condition the only visible evidence of fracture is a depression of about 2,5 cm in diameter over the zygomatic arch associated with limitation of mandibular excursion to the injured side and possible interference with mandibular opening or closing.

   The depression is obvious immediately after fracture of the arch, but it often becomes obscured by oedema shortly after injury only to become visible again when the swelling subsides in about a week.

    No other physical signs and symptoms typical of a fracture of the zygomatic bone are present.

   Isolated fractures of the zygomatic arch are uncommon. In Donaldson's (1961) series of facial fractures 3 per cent involved the zygomatic arch, and in 69 fractures of the zygomatic complex (Rowe and Killey, 1968) only four (6 per cent) were confined to the zygomatic arch. Knight and North (1961) found 10 per cent zygomatic arch fractures in their 120 cases of zygomatic complex fractures.

    Fractures of the zygomatic arch can be divided into two main varieties:

1. The triple fracture of the arch with a depressed V-type of displacement.

2. Comminution of the arch.

           In the V-type of displacement the apex of the V may impinge on the coronoid process and impede mandibular movements, especially lateral excursion to the injured side. In the absence of surgical correction this depression persists and constitutes a cosmetic deformity.

   When the zygomatic arch is comminuted, the fragments usually reposition themselves presumably as a result of movements of the temporalis muscle and coronoid process beneath them. Signs and symptoms may be minimal or absent.

   Summary of possible clinical findings in zygomatic complex fractures

1. Flattening of cheek.

2. Swelling of cheek.

3. Anaesthesia of cheek, temple, upper teeth and gingiva.

4. Periorbital haematoma.

5. Subconjunctival haemorrhage.

6. Tenderness over orbital rim and fronto-zygomatic suture.

7. Step deformity of infra-orbital margin.

8. Separation at frontozygomatic suture.

9. Ecchymosis and tenderness intra-orally over zygomatic buttress.

10. Limitation of ocular movement.

11. Diplopia.

12. Enophthalmos.

13. Lowering of pupil level.

14. Epistaxis.

15. Limitation of mandibular movement.

       Possible gagging of back teeth on injured side.

       Fractures of the nose and naso-ethmoid complex

       Applied surgical anatomy

       It is possible for the nasal bones alone to be fractured, but it is more usual for fractures to extend and involve the frontal process of the maxilla and the lower part of the medial wall of the orbit. In the latter case, there may be comminution of the lacrimal bones and the orbital plate of the ethmoid with associated lateral displacement of the medial canthus of the eye.

  Stranc and Robertson (1979) subdivided nasal complex fractures into three planes of injury depending on the force applied. In simple terms the first plane involves the nasal tip only, the second plane involves the whole of the external nose anterior to the orbital rim, while the third plane is a much more severe injury involving the medial orbital wall and sometimes the anterior cranial fossa. These latter injuries are now distinguished as fractures of the naso-ethmoid complex. Such a fracture causes considerable depression of the central part of the face without any disturbance of the occlusion.

   Fractures of the nasal region usually involve the nasal septum. Sometimes the septal cartilage is merely dislodged from its groove in the vomer but frequently the cartilaginous septum is fractured in a C-shaped pattern convex to the rear (Murray et al., 1984, 1986). In more serious injuries the vomer, and perpendicular and cribri­form plates of the ethmoid may be fractured and, in very severe injuries, there may be cerebrospinal fluid rhinorrhoea.

   The displacement of the fragments depends on the direction of the fracturing force. Force applied laterally to the nose leads to the nasal bones and associated portions of the frontal processes of the maxillae being displaced to one side. At the same time, the septal cartilage which is attached to the inner aspect of the nasal bones is subjected to a strain which causes it to fracture or be detached from its groove in the vomer. More violent force will, of course lead to comminution of the vomer together with the perpendicular and possibly cribriform plates of the ethmoid.

    Force applied anteriorly over the bridge of the nose leads to the nasal bones being driven inwards, while the frontal processes of the maxillae and lacrimal bone fracture and are splayed outwards. The attachments of the medial canthal ligaments of the eye are displaced laterally producing a traumatic telecanthus, the severity of which relates directly to the degree of impaction. All of this results in a flattened, depressed nose, and again the underlying septal cartilage and the vomer, and perpendicular and cribriform plates of the ethmoid may be variously involved.

   If untreated, the lateral type of injury will result in a deviation of the nose to one side, with chronic airway obstruction. Untreated anterior-type injuries leave a flattened nose with thickened bridge. More severe injuries leave the patient with telecanthus, chronic airway obstruction and often disturbance of lacrimal drainage.

   Signs and symptoms

   In the recent injury much of the skeletal displacement may be masked by the overlying oedema.

    It is usual for there to be bilateral circum-orbital ecchymosis and possibly subconjunctival haemorrhage, more marked on the medial aspect. The entire nose may be seen to be deviated to one side following a lateral injury while an anterior fracturing force produces a saddle-type depression of the bridge.

   In the recent injury there is invariably epistaxis, and when the blood has clotted there may be a discharge of clear serum. If the cribriform plate of the ethmoid has been comminuted, there may be a cerebrospinal fluid leak from which the patient may, allegedly but doubtfully, notice a salty taste. The tissue over the bridge of the nose is thin and the fragments of nasal bone may penetrate the skin, rendering the fracture compound. If the nostrils arc gently cleared of blood a nasal speculum can be used to inspect the nasal septum, which may be visibly torn or displaced or there may be a septal haematoma.

  Nasal fractures are common and some patients with facial injuries will have pre-existing nasal deformity as a result of previous injury. This can present a difficult diagnostic problem, particularly when the patient is unable to give a lucid history. Palpation of the nasal skeleton will usually distinguish a fresh injury from a previous deformity. The underlying nasal bones will be mobile and sometimes comminuted. Sharp step deformities may be felt and the bony complex will be acutely tender. When there is extensive comminution, the entire area gives the sensation of lead shot under the palpating finger.

    It is important to determine whether the medial canthal ligament of the eye is displaced as it may be in those fractures which involve the deeper bony components of the medial orbital wall. The intercanthal distance should be measured and also the distance of each medial canthus from the midline as the displace­ment may be unilateral. Bowerman (1985) states that an intercanthal measurement greater than 35 mm is indicative of canthal displacement.

       Summary of possible clinical findings in nasal complex fractures

1. Bruising of skin over nasal bones.

2. Laceration of skin of bridge of nose.

3. Bilateral medial orbital ecchymosis.

4. Epistaxis.

5. Deformity of nose.

5. Crepitus of bones of nasal complex.

6. Unilateral or bilateral telecanthus.

7. Airway obstruction.

8. Septal deviation.

10. Septal laceration or haematoma.

11. Cerebrospinal rhinorrhoea.

       These are the most frequent fractures of the facial skeleton in clinical practice. The vast majority of nasal fractures can be treated by closed manipulation and simple splinting. It is advisable to wait 5-10 days before reduction for the swelling to subside since this allows a clearer assessment of the injury.

More severe injuries, normally due to high-energy frontal impact, may need open reduction. These grossly displaced fractures of the naso-ethmoid complex, which are often associated with other facial injuries, will be considered later.

       Reduction

       Simple nasal complex fractures with minimal displacement can be reduced under local analgesia (Cook et al., 1992). General anaesthesia with an oral endotracheal tube is still preferred by most surgeons and is definitely indicated when there is significant deviation or septal fracture. An adequate throat pack is essential because haemorrhage may be profuse.

   Walsham's and Asche's forceps are used for manipulating the fragments. The unpadded blade of the Walsham's forceps is passed up the nostril and the nasal bone and associated fragment of the frontal process of the maxilla are secured between it and the padded blade externally. The fragments are manipulated into their correct position and then the manoeuvre is repeated on the opposite side.

   Next, the vomer and the perpend perpendicular plate of the ethmoid and the vomer is common when significant deviation of the nasal bones is present. Resection of the cartilage and bone adjacent to this fracture is advocated to prevent later collapse and poor nasal airway function. Despite their findings it has to be said that this procedure is not commonly carried out in clinical practice.

  When the septum has been realigned the finger and thumb of one hand are used to com­press the lacrimal bones and medial walls of the orbit on each side to achieve a narrow bridge to the nose. Finally, a fine sucker should be passed down each of the nares to ensure that they are clear and that the patient has a patent nasal airway.

       If the nasal bones are severely comminuted it is often sufficient to mould the nose into shape between the thumb and forefinger, or by applying a thumb along each side of the nose and squeezing. Such fractures tend to be less stable after reduction.icular plate of the ethmoid are 'ironed out' with the Asche's septal forceps, using one blade each side of the septum and then, if possible, the septal cartilage is grasped and brought forwards and reposi-tioned in its groove in the vomer. Murray et al. (1984) maintain that consideration should be given to a limited submucous resection of the septum in many nasal fractures.

    Fixation

       When the fracture is minimally displaced, it may be unnecessary to splint the nose following reduction. Usually, however, some sort of splint fixation is advisable.

    There are a number of custom-made malleable or thermoplastic splints available but many surgeons still prefer a plaster-of-Paris splint. This consists of eight layers of plaster-of-Paris bandage cut so as to produce a strip of plaster across the bridge and covering either side of the nose, with an extension up to the forehead.

    The splint is moulded into place while soft and held while it sets. It is then fixed into position with strips of adhesive tape across the forehead and across the nasal bridge. A light nasal pack can be placed for 24 hours to help haemostasis but care must be taken to prevent over-packing and displacement of the nasal bones.

    Ideally a fresh, accurately fitting splint should be applied a few days later when the postoperative oedema over the nasal region has subsided. A nasa] splint should be left in situ for about 10-14 days in total. The aim of a splint is to help maintain an already adequately reduced and stabilized fracture. It is tive and reminds the patient to avoid unnecessary contact.

   Simple external splints are not effective in maintaining unstable reductions in the hope that they will heal properly. If the nasal fracture is too mobile to be efficiently stabilized with an external splint a lead-plate splint, or Silastic button splint, is used either side of the nose. These plates, each with an upper and lower hole through the centre, are shaped and fitted either side of the nose with the edges carefully moulded to prevent chafing of the skin. They are held in position by a mattress suture of tantalum or 0.35 mm soft stainless-steel wire, which is passed through the holes in the plates with a fine awl, the wires transfixing the tissues and passing beneath the nasal bones. This splint is left in situ for about 3 weeks.

       Occasionally, if the nasal complex region is particularly flat, it is impossible to achieve a satisfactory result with closed reduction methods. Open reduction, as described in the section on naso-ethmoid fractures, may be a better but more demanding alternative.

       Zygomatic complex fractures with minimal displacement that are not causing symptoms do not necessarily require treatment. According to most reported series of fractures of the zygoma, around 20 per cent will not need surgical intervention. The indications for treatment are as follows:

(a) To restore the normal contour of the face both for cosmetic reasons and to reestablish skeletal protection for the globeof the eye.

(b) To correct diplopia.

(c) To remove any interference with the range of movement of the mandible.

       An assessment of the significance of the displacement is important. The cosmetic expectations of the patient are relevant and sometimes an obviously displaced zygoma is left if the patient is elderly and a poor operative risk. At the other end of the scale, in a young, fit patient, even a minimally displaced fracture should be elevated to restore contour, minimize the problems of late collapse and relieve pressure on the infra-orbital nerve (De Man and Bax, 1988). In general, cases with diplopia always require operation.

       Reduction

       Surgical reduction of the displaced zygomatic complex becomes increasingly difficult with the passage of time. If necessary the operation can be delayed for up to 10 days to allow the swelling to settle. After 2 weeks the displaced bones start to become bound down by organizing scar tissue but it is still better to attempt primary correction rather than to settle for secondary reconstruction. In practice, reduction can usually be achieved up to 6 weeks after injury and sometimes even longer.

   Many zygomatic complex fractures are stable after reduction without any form of fixation, particularly where the displacement is essentially a medial or lateral rotation around the vertical axis without separation of the frontozy-gomatic suture (Rowe, 1994). Recent fractures tend to be more stable than those which are more than 2 weeks old. Fractures in which there is disruption of the frontozygomatic suture and those which are extensively comminuted are usually unstable.

   Indirect reduction of a zygomatic fracture can be carried out by a temporal, percutaneous or intraoral approach.

   Temporal approach

       The Gillies temporal approach is popular and straightforward. The operation depends on the fact that the deep temporal fascia is attached along the superior surface of the zygomatic arch, whilst the temporalis muscle passes beneath the arch to be attached to the coronoid process and down the ramus as far as the retromolar fossa. Therefore, if an incision is made in the hairline in the temporal region and the temporal fascia is incised, it is possible to pass an instrument down on the surface of the temporalis muscle beneath the zygomatic arch. The zygomatic bone or its arch can then be elevated into its correct position.

       A oblique 2 cm incision is made within the hairline between the bifurcation of the superficial temporal vessels. The temporalis fascia is exposed and incised and a Rowe's or Bristow's elevator passed down beneath the zygomatic bone, which is then elevated back into position. The position of the bone is confirmed by palpation of the infra-orbital rim and the cheek prominence using the uninjured side is for comparison. One advantage of the Bristow's elevator is the ability to palpate the infra-orbital rim with one hand while manipulating the bone with the other. When palpating the reduced position it is important to relate the prominence of each zygomatic body to a common point distant from the bone, such as the glabellar region, since periorbital soft tissue swelling on the fractured side can give a false impression. When a satisfactory stable reduction has been obtained the temporal fascia and skin are sutured.

    The Gillies approach is undoubtedly the most versatile method of indirect reduction. It is simple to perform and gives excellent control of the fractured zygomatic complex during all stages of reduction.

    Percutaneous approach

    This rapid method is most useful in non-comminuted fractures with medial displacement and no distraction of the frontozygomatic suture. A number of hook-ended instruments have been designed for this purpose The Gillies approach is undoubtedly the most versatile method of indirect reduction. It is simple to perform and gives excellent control of the fractured zygomatic complex during all stages of reduction.

    Percutaneous approach

       This rapid method is most useful in non-comminuted fractures with medial displacement and no distraction of the frontozygomatic suture. A number of hook-ended instruments have been designed for this purpose The location of the stab incision for insertion of the hook elevator is found at the intersection of a perpendicular line dropped from the outer canthus of the eye and a horizontal line extending laterally from the alar rim of the nostril. The point of the instrument is kept in close contact with the undersurface of the body of the zygoma and traction is applied to reduce the fracture. A single fine suture is all that is required to close the wound, which is virtually invisible when healed.

       Intraoral approach

       Some surgeons prefer to elevate the zygomatic bone from an intraoral approach. However, although this technique has a long history, it is not widely practised. An incision is made in the upper buccal sulcus immediately behind the zygomatic buttress and a curved elevator is passed supraperiosteally to engage the deep surface of the zygomatic bone. Forward and outward pressure is exerted to reduce the fracture (Balasubramaniam, 1967).

       Fixation

       Temporary support

       If the reduced zygomatic complex is unstable as a result of comminution or delayed reduction some form of temporary support can be considered as an alternative to open reduction. Antral packs were advocated for this in the past but the indications for their use have waned considerably with the advent of miniature bone plates. Nevertheless, antral packing is still an effective way of managing the grossly comminuted fracture, and can have a useful part to play in the support of orbital floor fractures where there is no bone loss. For com­minuted zygomatic fractures the pack should be directed chiefly to the outer aspect of the antrum beneath the body of the zygoma, whilst for support of the orbital contents it should be applied much more gently in the space between the undersurface of the orbital floor and the antral floor (i.e. the antral surface of the maxillary alveolus).

  The sinus is approached through a buccal sulcus incision. An opening is usually present as a result of the fracture; otherwise a window into the sinus is made through the canine fossa. The opening is enlarged, and any blood clot and fragments of bone within the sinuses are evacuated. The operator gently repositions any fragments of the orbital floor with a finger and the antrum is then packed in a concertina pattern. The pack should be composed of 5 cm ribbon gauze soaked in Whitehead's varnish (Pigmentum lodoform Compound: B.P.C.). This will remain uninfected during the period needed for stabilization of the fracture. White-head's varnish contains a number of aromatic resins, which are very slowly broken down to produce benzoic acid. It is this slow release of a potent antiseptic, together with the waterproofing property of the compound, which makes it superior to other media. Antral packs are best left completely enclosed within the sinus, beneath the suture line in the buccal sulcus, by which route they are easily removed. The presence of a pack must be recorded prom­inently in the patient's operation notes.

   An antral pack should be retained until the bone it is supporting is stable, which will normally be about 3 weeks. However, in some grossly comminuted fractures it may be necessary to retain the pack for much longer, and indeed to replace a pack by another if the fragments are still mobile after the initial removal. If support is not maintained in this way, late contracture and flattening of the profile may occur.

    When packing the antrum great care must be taken not to displace any bony spicules of the orbital floor against the optic nerve and ophthalmic artery. For this reason any pack used to support the orbital floor must be very carefully applied, and in most cases it is advisable to expose the orbital floor from above to ensure controlled application of the support. For the same reason when there is an associated Le Fort I, II or III fracture, this should be reduced and immobilized before packing the antrum. If the antrum is packed and the mid-face is then manipulated, the antral pack will be forced against the orbital floor with the risk of damage to the orbital contents.

       Balloon catheters in the antrum have been advocated instead of a pack but they have the disadvantage of expanding uniformly in all directions so that pressure cannot be exerted to the correct sites with any degree of accuracy.

6. MATERIALS FOR SELF-CONTROL:

A. Tasks for self-control: 1. Anatomy and physiology of face skeleton. 2.Anatomy of nasal and zygomatic bones. 3. Types of fracture of nasal and zygomatic bones.4. Clinical features of fracture of of nasal and zygomatic bones. 5. Basic method of examination of patient with fracture. 6. Additional method of examination of patient with fracture of nasal and zygomatic bones.7. Treatment of fracture of nasal and zygomatic bones.

B. Tasks for self-control: 1. Patient, 30 years old, has a nasal bleeding as a result of fracture of nasal bones. How to repone and to fix fragments? (Answer: By nasal raspator).

2. A patient, 35 years old, after a fight came to the clinic with complaints on complicated nasal breathing, pain in the nose, bruises under the eyes on each side, edema. What diagnosis is most reliable? (Answer: Fracture of nasal bones).

3. The patient, 50 years old, got the trauma of right half of the face by a blunt object. He came to the clinic with complaints about pain, face asymmetry, hard mouth opening, swelling of right half cheek and undereye areas. What diagnosis is most reliable? (Answer: Fracture of zygomatic of bone and arc).

C. Materials for test control. Test tasks with the single right answer (a=II): 1. Nasal liquorrhea takes place when: A. a fracture of the lattice or wedge-shaped bone; B. a fracture of the frontal bone; C. a fracture of the upper jaw; D. a fracture occipital bone. (Correct answer: A).

2. Displacement of nasal bones near its base indicates a fracture of: A. Nasal bones; B. Frontal appendices of upper jaw and nasal bones; C. Eye-sockets; D. Nasal partition. (Correct answer: B).

3.A hypodermic crepitus at the damage of nasal bones indicates a fracture of: A. the upper jaw with the breaking of mucous membrane; B. The lattice bone with the breaking of mucous membrane; C. The wedge-shaped bone; D. The frontal bone. (Correct answer: B).

D. Educational tasks of 3th levels (atypical tasks): Patient, 34 years old, complains of inability to open his mouth. Cosmetic defect in the left half of the face. Palpation of the infraorbital area is painfull, «born’s step» on the low edge of the orbit. Bleeding from the nose. What diagnosis can be expected to deliver? (Correct answer: the zygomatic bone fracture with displacement).

2. Patient, 20 years old, complains of inability to breathe through the nose, bruises on the lower edge of the eyelids with the transition to the upper eyelid on both sides. At the clinic was diagnosed basal skull fracture. (Correct answer: nasal bone fracture without displacement).

3. Patient complains of bad nasal breathing, at palpation pathological mobility in the lateral projection of the nose is noted. Which additional tests are needed? (Correct answer: X-ray of the nasal bones).