spinal

Question 1

What factors are assoc. with preventable neurological deterioration?

Answer 1

1. The injury not being recognised initially, e.g. not being specifically examined for, occult or masked by other injuries 2. The onset of the secondary effects of the spinal cord injury involving oedema and/or ischaemia 3. Aggravation of the initial spinal cord lesion by- inadequate oxygenation and/or hypotension or- inadequate vertebral immobilisation.

Question 2

Where do vertebral and spinal cord injuries most commonly occur?

Answer 2

Vertebral injuries

• Cervical 60%,
• thoracic 30%,
• lumbar 4% and
• sacral 2%

Spinal cord injuries

• 5th, 6th and 7th cervical vertebrae, largely because of the greater mobility of these regions.
• The C5–6 and C6–7 levels account for almost 50% of all subluxation injury patterns in blunt cervical spinal trauma

Question 3

What are the 3 notworthy observations of assoc. injuries with spinal injuries?

Answer 3

1. Approximately 8–10% of patients with a vertebral fracture have a secondary fracture of another vertebra, often at a distant site.2. Often have other associated injuries, including head, intrathoracic or intra-abdominal injuries, which may modify management priorities3. Patients may complain of pain from other injuries and hence a back or neck injury may go unnoticed

Question 4

With respect to the autonomic nervous system, what are the cardiovasculareffects of spinal cord damage?

Answer 4

In complete quadriplegia, sympathetic denervation causes relaxation of resting vasomotor tone, resulting in generalized systemic vasodilatation.- It is recognised by dry extremities with variable warmth and colour during initial assessment.- In males, there may be penile engorgement or priapism.- Owing to the peripheral vasodilatation, there is a drop in total peripheral resistance, with consequent hypotension (neurogenic shock).

Question 5

With respect to the autonomic nervous system, what are thegastrointestinaleffects of spinal cord damage?

Answer 5

• a paralytic ileus develops but it is usually self-limiting and recovers over 3–10 days.- passive regurgitation of stomach contents precipitates an aspiration risk- complicated by a reduced capacity to cough and clear aspirated secretions.

Question 6

With respect to the autonomic nervous system, what are theurinaryeffects of spinal cord damage?

Answer 6

• Urinary retention is partly the consequence of acute bladder denervation and, in the early post-injury phase, due to spinal shock.- Catheter insertion is required to prevent over distension of the bladder in order to optimise recovery.

Question 7

With respect to the autonomic nervous system, what are thethermoregulatoryeffects of spinal cord damage?

Answer 7

Following cervical or upper thoracic spinal cord injury, the spinal patient effectively becomes poikilothermic.- In a cold environment, they are unable to vasoconstrict to conserve heat or shiver to generate heat. The patient is already peripherally vasodilated which promotes loss of heat and lowering of body temperature.- In the warm environment, although the patient is already peripherally vasodilated,the capacity to sweat is sympathetically controlled and therefore lost.

Question 8

How is muscle power assessed and reported?

Answer 8

Grade 0/5 No movement Grade 1/5 Flicker Grade 2/5 Movement present, but not a full range against gravity Grade 3/5 Full range of movement against gravity with no added resistance Grade 4/5 Full range of movement against gravity with added resistance but with reduced power Grade 5/5 Normal power

Question 9

How is the dorsal column sensation assessed?

Answer 9

Using a peice of cotton wool and testing for light touch.

Question 10

How is spinothalamic sensation assessed

Answer 10

• using a pin or sharp object. - proprioception, vibration and temp can also be assessed.

Question 11

What mechanisms are assoc. with cervical spine fractures?

Answer 11

1. hyperflexion, hyperextension and flexion–rotation 2. vertebral compression3. lateral flexion or distraction.

Question 12

What is the role of corticosteroids in spinal injury?

Answer 12

• methylprednisolone given within 8 hours of injury can have a significant effect on recovery of motor function- consider its role carefully in those with contaminated injuries such as perforated bowel or established sepsis.- the initial dose is 30mg/kg over 15mins then 5.4mg/kg over 24hrs if <3hrs from injury or over 47 hours if 3-8 hrs after injury

Question 13

What injuries does hyperflexion produce?

Answer 13

1. a simple, stable wedge fracture2. a fracture with an anterior teardrop 3. bilateral anterior subluxation or bilateral facet dislocation. 4. clay shoveller’s fracture

Question 14

What is a clay shoveller’s fracture?

Answer 14

A clay shovelers fracture is an avulsion of the C6, C7 or T1 spinous processes assoc. with sudden load on a flexed spine

Question 15

Flexion injuries with anteroinferior extrusion teardrop fracture are assoc. with what?

Answer 15

This is often associated with retropulsion of a vertebral body fracture fragment or fragments into the spinal canal

Question 16

What are the features and consequences of hyperextension injuries?

Answer 16

1. Anterior widening of disc spaces, prevertebral swelling, avulsion of a vertebral body by the anterior longitudinal ligament,2. subluxation and crowding of the spinous processesEncroachment on the canal by an extruded disc or a posterior osteophyte may occur in patients with osteoarthritis of the cervical spine.

Question 17

What is common with flexion-rotation injuries of the cervical spine?

Answer 17

Unilateral facet dislocation or forward subluxation of the cervical spine.

Question 18

What is assoc. with vertebra compression injuries?

Answer 18

Vertebral compression injuries are assoc. with burst fractures.- The intervertebral disc is disrupted and driven into the vertebral body below and disc material may be extruded anteriorly into prevertebral tissues and posteriorly into the spinal canal.- The vertebral body may be comminuted to varying degrees, with fragments being extruded anteriorly and posteriorly into the spinal canal.

Question 19

What injuries are assoc. with lateral flexion injuries?

Answer 19

1. Uncinate fractures,2. isolated pillar fractures,3. transverse process injuries and4. lateral vertebral compression.

Question 20

What is a distraction cervical spine injury and what injuries is it assoc. with?

Answer 20

• Adistraction injuryis separation or pulling apart of two adjacent vertebrae withhigh chance ofcord injuryas its osseous and ligamentous supporting structures are pulled apart.- Adistraction injuryon the posterior side can lead to a compression fracture on the anterior sidegross ligamentous and intervertebral disc disruption.- A hangman’s fracture may also occur by combined distraction and hyperextension mechanisms.

Question 21

What are key features of C1 injuries?

Answer 21

1. C1 fractures of the atlas comprise 4% of cervical spine injuries and mechanisms generally involve hyperextension or compression. 2. Around 15–20% of fractures may be associated with a C2 injury and 25% may be associated with a lower cervical injury.3. The Jefferson fracture is a blowout fracture of the ring. Other fractures include isolated injuries of the posterior arch, the anterior arch and the lateral mass.

Question 22

What are key features of C2 injuries?

Answer 22

Axis fractures comprise 6% of cervical spine injuries, with an association with concurrent C1 injury in the majority of cases. There are three types of odontoid fracture:
- Type 1 is an avulsion of the odontoid tip. It is generally a stable injury and accounts for 5–8% of odontoid fractures - Type 2 injury is a fracture through the base of the dens and is generally unstable. It comprises 55–70% of odontoid injuries. In younger children, the epiphysis may be present and confused with a type 2 fracture - Type 3 is a subdental fracture of the odontoid extending into the vertebral body. It comprises 30–35% of odontoid fractures. .

Question 23

Describe a hangmans fracture

Answer 23

A hangman’s fracture is a bilateral neural arch fracture of C2.- It is a hyperextension injury and is associated with prevertebral soft tissue swelling, anterior subluxation of C2 on C3 and avulsion of theanteroinferior corner of C2.

Question 24

When are C3-C7 fractures defined as unstable?

Answer 24

1. the anterior and all of the posterior elements are disrupted
2. there is more than 3 mm overriding of the vertebral body above over the vertebral body below 3. the angle between two adjoining vertebrae is greater than 11° 4. the height of the anterior border of a vertebral body is less than two-thirds of the posterior border.

Question 25

What is the principle mechanism of injury assoc. with the thoracic spine?

Answer 25

- Hyperflexion with resultant wedging of vertebral bodies.  - due to the regidity of the thoracic cage and the assoc. costovertebral articulations, most thoracic spine injuries are stable (except where kyphosis is pronounced).

Question 26

What are key features of Thoracolumbar spine injuries?

Answer 26

1. thoracolumbar spine comprise 40% of all vertebral fractures responsible for neurological deficit and most are flexion or hyperflexion-rotation injuries. 2. Plain films may demonstrate - facet joint disruption, - evidence of interspinal ligament disruption, - posterior bony fragments protruding into the spinal canal and - burst fragments at the superior surface of the vertebral body. 3. These fractures are generally unstable.

Question 27

What are the key points of a lumbar spine injury when associated with a lap-sash seat belt?

Answer 27

They are broadly considered posterior distraction injuries of the vertebral arch in which the lap-sash seatbelt converts the hyperflexion mechanism to one of distraction.Plan films may show 1. a vacant or empty appearance of the vertebral body on the AP film 2. discontinuity in the cortex of the pedicles or spinous processes on the AP view 3. fracture, with or without dislocation in the lateral view, which may be subtle. These injuries are often associated with concurrent intra-abdominal visceral injuries.

Question 28

What is a chance fracture?

Answer 28

An oblique or horizontal splitting of the spinous process and neural arch, extending the superior posterior aspect of the vertebral body into and damaging the intervertebral disc.

Question 29

What is a horizontal fissure fracture?

Answer 29

This fracture is very similar to the chance fracture, with the exception of the fracture line, which extends horizontally through the vertebral body to its anterior aspect.

Question 30

What is a Smith fracture?

Answer 30

This spares the posterior spinous process. - The fracture line involves the superior articular processes, the arch and a small posterior fragment of the superior posterior aspect of the vertebral body. - Although the spinous process is intact, the posterior ligaments are disrupted.

Question 31

What are the features of spinal shock?

Answer 31

- Spinal shock may last for a few hours to several weeks, depending on the segmental level and extent of the cord injury. - During this period, both somatic and autonomic reflexes below the injured segments disappear. - Recovery from spinal shock is heralded by the return of the Babinski response, followed by the perineal reflexes

Question 32

What is the difference between primary and secondary spinal injuries

Answer 32

- Primary spinal cord injuries refer to the injuries directly caused by the trauma mechanism and its damaging energy onto the spinal cord. - Secondary spinal cord injuries are caused by other mechanisms often related to the initial trauma, i.e. hypotension, hypoxia, etc.

Question 33

What are the key features of Transverse spinal cord syndrome?

Answer 33

1. The spinal cord is completely damaged transversely across one or more adjacent spinal segments and no motor or autonomic information can be transmitted below the damaged area and ascending sensory stimuli from below the damaged spinal segments are also blocked. 2. The manifestations are: - total flaccid paralysis, anaesthesia, and analgesia - usually areflexia below the injured segment.

Question 34

With respect to transverse spinal cord syndrome, what does "sacral sparing" imply?

Answer 34

that some sensibility with or without motor activity in the areas supplied by the sacral segments is preserved in an otherwise complete transverse cord syndrome. - The presence of sacral sparing implies an incomplete injury, as some neurological transmission through the injured segments is preserved. Spinothalamic and corticospinal transmission to and from sacral segments are located in the outermost parts of the spinal cord and are, therefore, immediately adjacent to the origin of the spinal cord’s blood supply.

Question 35

What occurs in an acute central cervical cord syndrome?

Answer 35

- The central part or grey matter of the spinal cord is injured. - Transmission in the outer rim of the spinal cord is essentially intact but impaired.

Question 36

What are the features of an acute central cervical cord syndrome?

Answer 36

1. motor function: there will be weakness in both upper and lower limbs, with weakness marked in the upper limbs 2. sensation: there is sensory loss in both upper and lower limbs, which is more severe in the upper limbs 3. reflexes are variable.

Question 37

When is an acute central cervical cord syndrome typcially seen?

Answer 37

It is frequently caused by a hyperextension injury and is typically seen in older patients with cervical spondylosis. - the cord is compressed between posterior osteophytes and the intervertebral disc in front and the ligamentum flavum behind.

Question 38

What occurs in an acute anterior cervical cord syndrome and how do they occur?

Answer 38

1. The anterior half of the spinal cord – the region supplied by the anterior spinal artery – is damaged and there is motor loss or paralysis below the level of the injured segment(s).2. The are frequently the result of flexion–rotation or vertical compression injuries.

Question 39

What clinical features would you expect to see in an acute anterior cervical cord syndrome?

Answer 39

1. Spinothalamic transmission is impaired and thus there is analgesia with loss of temperature sensation and coarse touch. 2. As the dorsal columns are relatively intact, there is some preservation of joint position, vibration sense and fine touch - In the acute injury patient interpretation of this may be poor and manifest as preservation of vague and poorly localised sensation in the extremities

Question 40

What is Brown-Séquard’s syndrome?

Answer 40

1. It a functional cord hemisection with dissociated sensory loss because one half of the cord is damaged. 2. In a pure Brown-Séquard lesion, - ipsilateral motor function is impaired, as are light touch, joint position sense and vibration. - contralateral spinothalamic sensation (pain and temperature) is impaired, whereas ipsilateral sensation is relatively preserved.  - Reflexes are variable.

Question 41

What is posterior cord syndrome?

Answer 41

1. It is an uncommon injury that causes contusion or disruption to the dorsal columns, leading to impaired or disrupted proprioception, vibration and fine touch sensation. 2. It is usually the result of penetrating trauma to the back or a hyperextensioninjury in association with fractures of the vertebral arch.

Question 42

What factors can impact or potentiate secondary spinal cord damage?

Answer 42

1. inappropraite manual handling2. hypoxia and hypotension3. acute resonse to injury with assoc. metabolic changes  in a previously undamages spinal cord.

Question 43

What features could indicate a spinal cord injury in an unconscious patient?

Answer 43

1. paradoxical breathing or chest wall movement in the absence of a major airway obstruction, stove-in or large flail chest  2. priapism suggests quadriplegia or high to mid-thoracic paraplegia 3. preserved facial grimace in the absence of a response to painful stimuli in the limbs 4. lower limb flaccidity in the presence of normal upper limb tone suggests paraplegia 5. observed upper limb movement in the absence of lower limb movement suggests paraplegia 6. the combination of the persistent bradycardia and hypotension despite volume challenge where this is accompanied by a flaccid rectal sphincter

Question 44

 Identify the parts of the spinal cord

Question 45

What is the inury presented and what clinical features would present?

Answer 45

Central cord syndrome- central cord haemorrhage and oedema- parts of 3 main tracts involved on both sides- upper limbs more affected than lower limbs

Question 46

What is the injury here and what are the clinical features?

Answer 46

Anterior spinal artery syndrome where the artery is compressed by bone or cartilage spicules with the shaded area affected- motor function and pain sensation is lost bilaterally below injured segment- position sense is preserved

Question 47

What is the injury presented and what are the clinical features?

Answer 47

Brown-Séquard's syndrome where one side of the cord is affected. - there is loss of motor function and position sense on the same side and of pain on the opposite side

Question 48

What is the injury here and what are the clinical features?

Answer 48

Dorsal column syndrome.  - It is uncommon - position sense is lost below the lesion- motor function and pain sense is preserved

Question 49

What are the features of the dorsal column?

Answer 49

• touch, pressure, vibration, joint position sense• uncrossed in the spinal cord• cross in the medulla superior to the gracile and cuneate nuclei• sacral fibres most medial• cervical fibres most lateral

Question 50

What are the features of the anterolateral tract?

Answer 50

• fibres cross at level of input• sacral fibres most lateral in columns• cervical fibres most medial

Question 51

What are the features of the Lateral spinothalamic tract?

Answer 51

• carries fibres responsible for pain and temperature sensation• crosses to the opposite side of the cord at level of entry• sacral sensation is at the periphery     - if spared indicates intact peripheral perfusion

Question 52

What are the features of the Ventral spinothalamic tract?

Answer 52

• touch and pressure

Question 53

What are the features of the Lateral corticospinal tract?

Answer 53

• innervates distal limb muscles• controls fine motor movements• comprises 80% of the fibres of corticospinal tracts• fibres decussate at medullary pyramids    - fibres crossed in spinal cord

Question 54

What are the features of the Ventral corticospinal tract?

Answer 54

• innervates axial and proximal limb muscles• controls postural and gross limb movements• comprises 20% of fibres of corticospinal tracts• descends ipsilaterally  - does not cross until the level of synapse with LMN

Question 55

What spinal tracts are sensory?

Answer 55

1. Anterolateral tract2. Lateral spinothalamic tract3. Ventral spinothalamic tract 4.  Dorsal columns

Question 56

What spinal tracts are motor?

Answer 56

1. Lateral corticospinal tract2. Ventral corticospinal tract

Question 57

What are the key points assoc. with SCIWORA?

Answer 57

Spinal Cord Injury Without Radiographic Abnormality 1. rare entity     - incidence of 1:1,000 cervical injuries     - nearly all cases follow blunt injury 2. most commonly involves upper cervical cord 3. commonest types of injury    - epidural haematoma    - direct neuronal injury from degenerative spine (e.g central cord syndrome)

Question 58

Identify the following areas