Cortex - Adult trauma (spinal cord injuries) 1

Question 1

What can the spinal cord be injured by ?

Answer 1

Contusion, compression, stretch or laceration

Question 2

Define what spinal shock is

Answer 2

A physiologic response to injury with complete loss of sensation and motor function and loss of reflexes below the level of the injury. Spinal shock usually resolves in 24 hours

Question 3

What reflex is absent in spinal shock and subsequently returns following resolution of spinal shock ?

Answer 3

The bulbocavernous reflex is a reflex contraction of the anal sphincter with either a squeeze of the glans penis, tapping the mons pubis or pulling on a urethral catheter

Question 4

Define what is meant by neurogenic shock

Answer 4

• Occurs secondary to temporary shutdown of sympathetic outflow from the cord from T1 to L2, to hypotension and bradycardia which usually resolves within 24‐48 hours.
• Priapism (painful and persistent erection) from unopposed parasympathetic stimulation may be present.
• Usually due to injury to the cervical or upper thoracic spinal cord

Question 5

What is the treatment of neurogenic shock ?

Answer 5

IV fluids

Question 6

How can spinal cord injuries be classified ?

Answer 6

As complete or incomplete

Question 7

Define what complete spinal cord injury is

Answer 7

Spinal cord injury which results in no sensory or voluntary motor function below the level of the injury

Question 8

Define what is meant by incomplete spinal cord injury

Answer 8

• Spinal cord injury where some neurologic function (sensory and/or motor) is present distal to the level of injury.
• Sacral sparing with preservation of perianal sensation, voluntary anal sphincter contraction and big toe flexion indicates incomplete spinal cord injury indicates some continuity of the corticospinal (motor) and spinothalamic (course touch, pain, temperature) tracts and indicates a better prognosis

Question 9

What is the common mechanism of injury for which spinal cord injuries occur ?

Answer 9

Often high energy injuries and often occur with other injuries.

Question 10

Shock in the presence of spinal cord injury should be assumed to be neurogenic ? T/F

Answer 10

False!

It should not be assumed and hypovolaemic is much more common

Question 11

What is the treatment of spinal cord injuries ?

Answer 11

• Immobilization (cervical collar & sandbags, spinal board)
• Traction may be required to reduce dislocations or stabilize unstable cervical spine injuries
• Surgery may be required to relieve pressure on the cord or to stabilize unstable injuries

Question 12

Different syndromes / patterns of injury exist depending on the area of the cord injured, describe the typical pattern of central cord syndrome and the typical injury causing it

Answer 12

• It is the most common spinal injury pattern and usually occurs with a hyperextension injury in a cervical spine with OA
• Often there is no associated fracture or dislocation (Spinal Cord Injury Without Radiographic Abnormality, SCIWORA).
• Paralysis of the arms more than the legs occurs due to the corticospinal (motor) tracts of the upper limbs being more central and those for the lower limbs being more peripheral in the cord.
• Sacral sparing is typically present.

Question 13

Different syndromes / patterns of injury exist depending on the area of the cord injured, describe the typical pattern of anterior cord syndrome

Answer 13

Loss of motor function (corticospinal tracts) as well as loss of coarse touch, pain and temperature sensation (lateralspinothalamic tract) whilst proprioception, vibration sense and light touch are preserved (dorsal columns).

Question 14

Different syndromes / patterns of injury exist depending on the area of the cord injured, describe the typical pattern of posterior cord syndrome

Answer 14

• There is loss of dorsal column function (proprioception, vibration sense and light touch)
• It is rare

Question 15

Different syndromes / patterns of injury exist depending on the area of the cord injured, describe the typical pattern of Brown‐Sequard syndrome and what causes it

Answer 15

Results from hemisection of the cord usually from penetrating injury eg stab wound.

Ipsilateral paralysis and loss of dorsal column sensation occurs with contralateral loss of pain, temperature and coarse touch sensation. This is due to nerve fibres of the spinothalamic tracts crossing to the other side of the cord one or two levels above their entry into the cord whilst the nerve fibres of the other tracts cross higher up in the medulla.

Question 16

How do pelvic fractures tend to occur in young people and in old people ?

Answer 16

• In young people - high energy injuries
• Old people - with OA can sustain pubic rami fractures from low energy injuries

Question 17

What is the pelvic ring formed by ?

Answer 17

• The sacrum
• Ilium
• Ischium
• Pubic bones with strong supporting ligaments

Question 18

Explain the idea of what happens when the pelvic ring is disrupted

Answer 18

If the pelvic ring is disrupted in one place then there is invarably a disruption elsewhere in the ring (like a polo mint you cant brake it in one place)

Question 19

What are the 3 main patterns of pelvic fractures ?

Answer 19

• A lateral compression fracture
• A vertical shear fracture
• An anteroposterior compression injury

Question 20

Describe what lateral compression fractures of the pelvis are and how they commonly occur

Answer 20

Occurs with a side impact (eg RTA) where one half of the pelvis (hemipelvis) is displaced medially. Fractures through the pubic rami or ischium are accompanied by a sacral compression fracture or SI joint disruption.

Question 21

Describe what a verical shear fracture of the pelvis is and how they commonly occur

Answer 21

Occurs due to axial force on one hemipelvis (eg fall from height, rapid deceleration) where the affected hemipelvis is displaced superiorly.

Question 22

Describe what an anteroposterior compression injury of the pelvis is

Answer 22

• May result in wide disruption of the pubic symphysis the pelvis opening up like the pages of a book
• Substantial bleeding from torn vessels occurs

Question 23

Bleeding often occurs in high energy pelvic fractures - what is done to treat the bleeding ?

Answer 23

Fluids given for blood loss

A tied sheet or a special pelvic binder around the outside of the pelvis to hold the reduction and allow clotting of the vessels

Question 24

If there is ongoing haemodynamic instability following a pelvic fracture despite initial interventions what is done ?

Answer 24

Angiogram and embolization or open packing of the pelvis if laparotomy is required for co‐existing intra‐abdominal injuries.

Question 25

What clinical examination is mandatory following a pelvic fracture ?

Answer 25

A PR exam is mandatory to assess sacral nerve root function and to look for the presence of blood.

Question 26

How are low energy pelvic fractures in the eldery usually treated ?

Answer 26

Settle with conservative management over time

Question 27

Fractures of the acetabulum are usually high energy injuries - what injury can be associated with certain acetbaulum fractures ?

Answer 27

• Hip dislocation may be associated with posterior fractures of the acetabulum
• The posterior wall is fractured as the head of the femur is pushed out the back e.g. a car driver’s knees collide with the dashboard in a road traffic accident.

Question 28

How are acetabulum fractures diagnosed ?

Answer 28

• Plain X‐rays (oblique views may help)
• CT scans help to determine the pattern of the fracture and are essential for surgical planning.

Question 29

What is the treatment of acetabulum fractures ?

Answer 29

• Undisplaced fractures or small wall fractures may be treated conservatively.
• As with most intra‐ articular fractures, unstable or displaced fractures require anatomic reduction and rigid fixation
• Older patients may be treated with total hip replace