Skull, mandubular, pelvic. and spinal fracture Flashcards
What are the key points of the initial assesment of pelvic fractures?
- Assessment of the whole animal is essential
- Airway, breathing and circulation (additional assessment includes D-disability e.g. mentation and E-external injuries e.g. visible sites of haemorrhage)
- Radiograph or TFAST/TPOCUS chest
- Determine integrity of urinary tract (contrast radiography or ultrasound)
- Neurological deficits particularly with sacrococcygeal luxation (tail-pull) injury in the cat with UMN or LMN deficits resulting in spastic or atonic bladder
- Finally radiograph the pelvis-remember it is a box like structure therefore a single fracture/luxation cannot occur in isolation.
What are the management options for pelvic fractues?
- Conservative management: less invasive, less expense, outcome less predictable (poorer?) and recovery more prolonged
- Put in cage
- Surgical management: invasive and expensive, but likely to provide more rapid and fuller return to function, rapid pain relief, and potentially better outcomes
What factors do you need to consider when deciding on treatment options for pelvic fractures?
What pelvic fractures are normally operated on?
- Is the patient ambulatory? - probably don’t need to do anything
- How long has fracture been present? Manipulation of the fracture becomes more difficult, but not impossible, 5 days after the traumatic event
- Is the weight-bearing axis involved?
- Is the acetabulum involved?
- Is the pelvic canal diameter reduced (< 50%)? if left in this state then chronic constipation or dystocia in the intact female may result
- Are there multiple problems e.g. limb fractures?
- As a general principle usually operate on ilial, acetabular, and bilateral fractures
What is the weight bearing axis of the pelvis?
- the ilial shaft and wing
- the iliosacral articulation
- the acetabulum
What kind of fracture do RTS ‘shunting injury’ cause?
What are the key features of these ?
often cause sacral fracture and sacroiliac luxation
* These injuries may be stable
* They can be bilateral
* Often accompanied by neurological abnormalities
including sciatic neuropathies and urinary incontinence
* Can be very painful particularly if there is bilateral
sacroiliac luxation
Always look for other pelvic fractures (eg pubis and ilium)
How are sacral fracture and sacroiliac luxation managed?
What are the complication of surgical management
- Can be managed conservatively if greater than 50% of articular surfaces are in contact
Surgical management can be difficult and is prone to error including failure to engage the body of the sacrum in lag screw fixation or entering the neural canal with catastrophic consequences
Options include:
* large lag screw ± anti-rotational wire
* trans-ilial pin if one of the hemipelvis’ is intact
What are the key featurs of ilial shaft fractures?
How are they surgically managed?
What are they complications?
- Usually long oblique fractures
- Caudal fragment often displaces medially narrowing the pelvic canal diameter - therefore surgical management
- Well contoured plate with preferentially one or two screws in the body of the sacrum. Ideally engage six cortices either side of the fracture
- A long oblique fracture can be managed with lag screws alone
(The pelvis is inherently stable and therefore very rigid repair is not always necessary)
Complications
* Reduction can be difficult especially if the injury is chronic (greater than 5 days old)
* Iatrogenic damage to the sciatic nerve is a real risk
* Management of these fractures requires considerable experience
What are the common methods of repairing acetabular fractures?
What are the issues with these fractures?
Most common methods:
* plate fixation (acetabular plate, standard or locking plates or reconstruction plates)
* mid-acetabulum: screws, wire and methylmethacrylate composite
* If complex or cost issues then a femoral head and neck excision can be adopted but wait to see what function is gained with a conservative approach before performing this surgery
Issues:
* weight bearign part of the pelvis
* Failing to reconstruct fractures of the caudal third can result in poor outcome despite apparent reduced weight bearing in this area.
* Comminution of the medial wall is particularly difficult to manage
What are the concerns with pubic fractures?
What is the treatement for pubic fractures?
- These may be of little concern unless they are associated with rupture or loss of the pre-pubic tendon and a ventral hernia
- Bladder incarceration can occur in this hernia
- Generally pubic fractures require no treatment and the pre-pubic tendon rupture occurs with an intact pubis
What are the common site for spinal fractures?
Tend to occur where a more rigid section of the spine meets a more flexible area e.g. T/L junction (the most common site), L/S junction and C spine
What is the inital management of suspected spinal fractures?
- These patients are unstable
- The usual approach is applied to these trauma cases ABC (airway, breathing and circulation)
- Careful palpation may reveal the site of spinal instability
- If these patients are showing obvious neurological deficits e.g. no tone in the hind limbs or tail or the Schiff Sherrington posture with no hind limb tone and hyperextended forelimbs then assume there is severe spinal trauma - consider euthanasia
- Support the back at all times.
- The use of a rigid carrying board upon which the patient can be strapped is very useful.
- Give analgesia but avoid anaesthesia or deep sedation unless absolutely necessary as the the muscle spasm and tone provide local support over the fracture site
- Radiograph the spine at the first opportunity
What neurologicla evaluation shold you do with a susspected spinal fracture?
What posture is being shown here?
- Assess tone in the fore, hind limbs and tail
- Where is the most marked muscle spasm?
- Is there a cut off of the panniculus/cutaneous trunci reflex
- Is there a perineal reflex?
- Is the patient showing a Schiff-Sherrington posture suggestive of cord transection between the fore and hind limbs
- Most importantly-is there conscious pain perception (nociception) on applying painful stimuli to the hind limb or tail if T/L lesion, or hind, forelimbs and tail if cervical?
- This means that the animal looks round or vocalises when a painful stimulus is applied not that it just withdraws the limb (if just withdraws then spinal refelx is intact not the whole cord)
- This is the single most important factor that determines the likelihood of recovery from a spinal injury
- If there is no deep pain sensation the prognosis for the animal is poor
What is the the prognosis in a markedly overridden fracture in a deep pain negative dog?
What is the the prognosis in a lower lumber fracture?
What is the the prognosis in a cervical region fracture?
What is the the prognosis in a sacral fracture?
- A markedly overridden fracture in a deep pain negative dog carries a hopeless prognosis
- The lower lumbar region surrounds the cauda equina (nerves rather than the cord which are much more resistant to trauma)
- The cervical region has much greater space within the spinal canal allowing the cord greater movement without being compressed
- Injuries involving the sacrum maybe more significant because of their effect on urinary and faecal continence
What is the conservative management of spinal fractures? (eg those in the lumbosacral region)
- This consists of cage rest for 6-8 weeks
- Management of splints is difficult and this form of immobilisation can not be recommended
- Cats will not tolerate external splints but are amenable to cage rest
- Careful nursing is required particularly to avoid urine scalding and decubitus ulcers
- Appropriate analgesia should be provided at all times
What is a hemilaminectomy?
Take out the dorsolateral wall of the vertebral canal and allows blood clots and bone fragments to be removed and the cord decompressed
What surgical management options can be done to fix fractures inthe cervical spin resion?
What about int he thoracolumbar region?
In the cervical region pins and methacrylate bridges are the most versatile form of fixation - these are placed ventral to the vertebrae
This technique can also be performed dorsally in the thoracolumbar region but plating with either a standard dynamic compression plates or locking plates can also be employed at this site
What surgical post-op management techniques are helpful with spinal fractures?
- Irrespective of whether a conservative or surgical management option is adopted careful nursing particularly of the urinary system is essential and catheterisation with a closed collecting system is very helpful
During the period of cage confinement it is essential to provide sensory stimuli for the patient
Rehabilitation with physiotherapy is also an important part of their treatment
How do you diagnose sacrococcygeal luxations?
- Present with a flaccid tail, urinary retention or occasionally a flaccid bladder and overflow
- These cases can present with a grossly distended bladder if the owner was unaware of the original injury
- On occasions the cat might show concurrent mild sciatic neuropathy due to involvement of this nerve
- Examine the cat for other injuries e.g. scuffed nails suggestive of an RTA and breathing difficulties - Xray, pelvis and chest
What is the management for sacrococcygeal luxations?
- Conservative management with manual expressing of the bladder and medications to encourage micturition
- Bethanachol to increase detrusor tone
- Phenoxybenzamine or prazosin to reduce striated muscle tone and dantrolene to reduce smooth muscle tone in the urethra
- The owner can be taught how to express the bladder at home
- If this were to prove impossible and drug therapy fails a temporary cystostomy tube can be placed
Some advocate early amputation of the tail to reduce the
traction on the pelvic nerves especially if widely luxated
There are reports of reattaching the coccygeal vertebrae to the sacrum and improved recoveries as a result but this has not been established
What are the prognostic indicator for sacrococcygeal luxations?
The prognosis for this injury is good to fair but if there is no improvement after four weeks the prognosis worsens
Cats with deep pain sensation intact at the tail base within 48 hour of their injury have a better long term outlook and have been reported to regain bladder control within three days of this positive finding
What can bleeding in the ear indicate in a trauma case?
facial nerve damage
What are the key points of inducing a facial trauma case?
These patients will often have compromised airways, both as a result of the trauma and subsequent swelling and may also have reduced local reflexes
Be prepared to perform an emergency tracheotomy
In many cases it is better to place the ETT through either a tracheotomy or pharyngotomy
- This leaves the mouth clear of the tube and allows any fractures to be repaired with the mouth closed
- One of the most important features of fracture repair of the skull is the ability of the animal to close its mouth
Which of these fracture lines is favorable, why?
The green line shows a favourable fracture line as
chewing results in a compressive force
The red line shows an unfavourable fracture when
chewing distracts the fracture
What are the methods of fixing mandibular fractures?
- muzzle
- inter-canine acrylic bonding
- external skeletal fixator
- BEARD (Bi-gnathic encircling and retaining device)
- Plating
- Interfragmentray wiring - better success for maxillary fractures
- interdental wiring
How is mandubular symphyseal separation fixed?
- Wire or PDS (the latter tends to slip)
- The wire is placed caudal to the canine teeth and a large bore needle can be used to direct the wire to this location
- Some surgeons suggest that this fixation causes the canines to rotate inwards and advise interdental wiring.
- Soft foods for up to 6 weeks
- The wire usually loosens after a few weeks and will require removal
What is the key aspects of managing fractures of the skull and mandible?
Medical management of the initial trauma is often of greater importance in the survival of the patient than management of the fracture
- There are occasions when the fractured mandible or maxilla cannot undergo reconstruction
- Or the fracture is pathological e.g. severe periodontal disease
- In these cases a partial mandibulectomy of maxillectomy can be performed
- This is well tolerated and is used extensively in oncological surgery and can be combined with titanium implants
How do you fix temporomandibular luxations?
Place pencil or dowel across lower carnassial.
Press on rostral mandible and push caudally on luxated side
Relocation usually easily achieved
Feed soft foods for a week
What breeds suffer from temporomandibular dysplasia (locking jaw syndrome)?
Waht is it and When does this occur?
What is the treatment?>
- Bassets hounds and Persian cats
- Jaw locks open with slight deviation to side of the lock when the vertical ramus/coronoid process engages on the ventral zygomatic arch
- Occurs when yawning and can be present on either side
- It is due to increased lateromedial laxity in the TMJ
- Treatment is by partial resection of the ventral region of the zygoma
What are the two different forms of temporomandibular ankylosis?
what is the treatment for each?
This can be intracapsular or extracapsular
Both conditions result in an inability to open the mouth
Extra-articular forms include callus from caudal mandibular fractures, craniomandibular osteopathy and temporal muscle myositis
Intracapsular is caused by fibrosis and adhesions within the joint often secondary to a TMJ fracture
Extracapsular require resection of abnormal tissue from around the joint
Intracapsular requires a condylectomy which is well tolerated or if unilateral a hemimandibulectomy can be performed to free the contralateral side from the constraining effects of the ankylosis
Intubation of these patients is difficult due to an inability to open the mouth and an emergency tracheotomy maybe required
