Fractures Flashcards
What is a fracture?
Defined as a break or a breach in the continuity of normal anatomical structure of a bone by the application of excessive force resulting in 2 or more fragments of the involved bone
what is the aetiology of Mandibular Fractures?
1-most common facial fracture after the nasal bone and 10 most common fracture in the body. 2-Account for 36-70% of all facial fractures
3- in the developed would the most common cause is assault then sporting injury then RTA
4- this is the most common reason in the less developed world RTA (road traffic accidents)
5-Pathological factors can cause fractures such as an osteolytic lesion, spontaneously or with minimal force.
what are the different types of Mandibular fractures? and explain each.
1-Simple: un-displaced fracture the periosteum is intact, on the radiograph you will see a crack in the cortical area
2-Compound: perforated through the periosteum and presents externally, it could happen without seeing bone in the mandible but by breaking a socket as this will dispose it to infection.
3-Comminuted: the fracture has multiple lines, high impact fractures, more challenging to manage
4-Greenstick: more common in children involves flexing of the bone, the inner cortex will flex but
outer will fracture but no displacement
5-Pathological
Where can fractures happen in the mandible? and where are the most common sites?
A-Dento-alveolar: beneath the apexes of the teeth
B - Condylar: at the condylar neck, most common fracture, it is a point of weakness and the mandible will take the force of the impact.
C - Coronoid: the coronoid notch, it is the point of attachment of the temporalis muscle so it would be displaced into the infratemporal space so difficult to manage
D - Ramus
E - Angle: commonest fracture, because of the PE or UE third molar that weakens it
F - Body
G - Para-symphysis: second most common #, because the length of the canine
H - Symphysis
Where does the lateral pterygoids displace a condylar fracture?
Lateral pterygoid displaced a # condyle anteriorly & medially
where do the Medial pterygoids, temporalis and
massester displace a #?
temporalis, masseter & med. pterygoid displace proximal segment superiorly & medially
where do the and digastric, geniohyoid, genioglossus & mylohyoid displace a #?
digastric, geniohyoid, genioglossus & mylohyoid displace the distal segment inferiorly & posterior
What is a bucket handle fracture?
it is a fracture that happens in edentulous jaws bilaterally in the Para synthesis area on both sides and because of the mylohyoid, geniohyoid muscles it pulls back and down causing a bucket handle appearance
What is the guardsman’s fracture?
it is in a guard or a soldier position when they are standing for too long and the they would typically fall on their chin , it would fracture in the midline in the mandible and would transmit the force to the condylar neck which would fracture and because the lateral pterygoid muscle is attached to the pterygoid fovea it would contract the condyle inwards and displace medially.
What are the extra oral clinical features of a fracture of the mandible?
1-Pain: a sign, a fracture is very painful because the innervation of the mouth
2-Swelling: both intra and extra-orally
3-Bruising: it will start at the area of the part of the fracture and will develop to the neck and chest
4-Trismus: secondary to pain and swelling or muscle attachments that are displaced.
5-Concurrent soft tissue injury
Cut lip - dirt, tooth fragment
6-Otorrhoea external auditory meatus tear may accompany condylar fractures: blood and CSF will come out
7- Anaesthesia/Paraesthesia of lip: numbness and tingling, a fracture between the mental foramen and the lingula, the last molar and the premolar region.
What are the intra-oral clinical features of a mandibular fracture?
1-Haematoma in the floor of the mouth (Coleman’s sign) & buccal mucosa
2-Malocclusion
3-Tongue –bilateral parasymphasis, unstable position, swelling
4-Step deformity: displacement of the fracture you can sometimes just see a
Gingival laceration
5- Mobility or loss of teeth, # teeth
– inhaled, swallowed, in soft tissue
what is Coleman’s sign?
Haematoma in the floor of the mouth because the periosteum has torn and there is a haemorrhage beneath
what Radiographs would we take to determine the fracture presence?
2 views each at 90 degrees to the other.
DPT and PA mandible / facial – 2 views allow 3D visualisation : this would allow us to visualise the displacements in 3 dimensions and assess the need for management
what types of Radiographs can be taken for radiographs?
DPT
(if no DPT - Lateral Oblique : this is limited to dental hospital though)
occlusal view : not usually taken for mandibular fracture
Reverse Towne’s
Periapical: a fracture running through a socket
CBCT: best immaging
When do we not do treatment for fractures?
When there is no displacement evident on occlusion
When is there need for immediate management on a fracture and how is it carried out?
If there is displacement on or without occlusion this is usually done under GA and within 72 hours of presentation
What are the issues with detecting Mandibular fractures?
Mandible most likely to have issues with infection due to fractures in the sockets of the teeth this will impact management
there is delayed presentation that causes complication such as:
1-Wound dehiscence: wound breakdown,
2-infection: 20% of the cases,
3-exposure of hardware: when breakdown of mucosa,
4-non-union or fibrous union: long delay to treat or infection at the initial presentation and mobility
5- if any tooth are involved in the fracture they are rendered unvital: will require RCT under primary care
What are the two techniques for treating mandibular fractures?
Open techniques: where the margins are visualised with an incision, and the two fracture margins are aligned and fixed with mini plates
Closed technique: the margins are not visualised assumed that they are in place and then fix the mouth closed : Intermaxillary fixation (wiring the jaws together)
this is an old technique not used regularly
What is reduction when treating fractures?
1- Aligns the bone ends anatomically: correctly and anatomically and immobilised firmally
In an adult 4-6 weeks to heal and in child less
2- Recreates the normal anatomy
What is fixation in mandibular Tx?
> Prevents movement of the bone margins whilst healing occurs
Can be load bearing so that 100% of the functional load is supported by the fixation e.g 2 large plates
Can be load sharing such that the load is distributed between the hardware and the bone margins e.g one upper boarder plate and arch bars this would be done on the angle of the mandible
in an ideal world it should be load bearing
What are the methods of open fixation?
Mini-plates: they are made of titanium they osteointegrate, they are not removed, this can be put in through a transoral approach or through skin with a transbuccal trocha
Reconstruction plates: edentulous mandibles, thicker plates and longer
Compression plates: used before they would have asymmetrical holes so when put in place they would push the fractures together
Lag screws : buccal and cortical bone together
What are the methods of closed fixation?
Intermaxillary fixation: this is when the margins are in line and good interdigitation but used very rarely
Arch bars: preformed that are cut into size it has impact on the gingival health, uses ortho bands.
Eyelet wires: fiddly to place used after reduction to ensure everything is in place before using open fixation
Leonard buttons: easier technique there to up to six weeks
Cast cap splits: obalt chrome to cement on the teeth, the cement was black and horrible to remove
Gunning splints: use dentures and remove the anterior teeth and then wire them in place
What are the indications for Closed Reduction?
1- Non-displaced favourable factures
2- Grossly comminuted fractures
3- Significant loss of overlying soft tissue: if there is no soft tissues available to cover the plates
4- Edentulous mandibular fractures: too fragile for GA
5- Fractures in children: vacuum blow down splint in a greenstick fracture
6- Coranoid process fractures: can be managed conservatively but if not can use close technique especially bilaterally
7- Undisplaced condylar fractures
What is Champy’s Principles?
This dictate the number and place of plates depending on the stress and tension lines.
In the mandibular angle region, this line indicates that a plate may be placed either along or just below the oblique line of the mandible. load sharing than load bearing
Between the mental foramina 2 plates are recommended below the apices of the teeth in the area of the foramen you put one above and one below the foramen
What issues do we have in cases of a edentulous ridge?
Atrophic: less bone to reduce
Poorly vascularised so poor healing capacity
Lack of anatomical landmarks: makes it hard to align them anatomically correct
The less bone height the greater the complication rate
Use large reconstruction plates that are load bearing
these could be placed extra orally to avoid damage to the periosteum
What are post operative care to consider?
Ward v ITU( intensive care unit): depending on technique if closed ITU
Open v Closed Reduction
sent back to ITU to give Wire cutters or scissors - & instruction how / when to release IMF
Antibiotics - oral ;IV; IM; as most fractures are compound
Steroids: minimise swelling but only short term
Fluids
Post op x-rays – not now routinely taken
What are the complications of managing of mandibular fractures?
Non-union, fibrous union, mal-union
Altered occlusion
Distracted TMJ
Scars - trauma & iatrogenic
Infection 0.4-32%
Necrosis
Numb Lip
Exposed Plate: you would have to go back in and remove the plate with a compatible kit
What are the types of condylar fractures?
Extra-capsular: happen outside of the capsule at the neck of the condyle.
Intra-capsular: happens within the capsule and difficult to treat, not common
they are managed with a soft diet and NSAIDs
in some cases when you get a knock to the chin there might not be a fracture, there would be non evident in the radiograph: TMJoint diffusion
2 week of NSAIDs
how do we treat a condylar fracture?
if there is displacement you will get shortening of height on the affected side and that would cause deviation to the affected site and an open bite on the normal side.
Conservative if no displacement:
soft diet
analgesics / anti-inflammatory
Active with displacement:
open reduction and plating
closed - Leonard buttons and elastic traction
you would use IFM or Open reduction. If it is bilateral turn it into a unilateral fracture and then manage it
