DDMC SPINAL W1

The most common cervical joint to be affected by instability caused by rheumatoid arthritis is:

C1/2

In RA, what can instability be associated with?

• Neck pain

• Compression of adjacent structures such as brainstem, spinal cord and spinal nerve roots

What conditions can instability in the case of RA cause?

• Radiculopathy

• Myelopathy

What is happening in RA?

• Synovitis develops in the facet joints

• Erosion of adjacent ligaments, the annulus, disc spaces and bone

• Progressive instability

What are the 3 patterns of instability which occur?

1. The atlas shifts forward on the axis

2. One vertebral body shifts forward on the body of another, producing stepladder deformity (subaxial subluxation)

3. Axis telescopes (pushes up) into the atlas, driving the odontoid upwards

What is the symptomology of RA?

• Suboccipital pain (C2 nerve root involvement due to C1/2 subluxation)

• Subluxation causing C2 radicular pain is the most common radicular pain seen in RA

• Myelopathy (gait disturbance, loss of fine motor control in hands, numbness in hands, balance disturbance, hyper-reflexia, extensor plantar response, + Hoffman', clonus, motor/sensory loss)

• Brainstem compression less common (facial sensory disturbance, dyshagia, abnormalities in lower cranial nerves

• Sudden death RARE

What is the management of RA?

• Prophylactic surgery to prevent myelopathy from developing where subluxation has reduced canal diameter

• Posterior stabilisation of AA subluxation good for C2 nerve root pain

• Decompressive procedures to halt neurological deterioration

What are patients with AS at risk of?

• Atlantoaxial subluxation

• Cervical spine fractures

• Cervical spine stenosis

What is the symptomology of AS in the cervical spine?

• Reduced neck motion

• Progressive neck kyphosis

• Unable to look forward

• Chin-on chest deformity

What is the commonest radiological feature in AS?

• Vertebral squaring

• Syndesmophytes

At what 2 cervical segments do spinal fractures in AS most often occur?

• C5-C6

• C6-C7

What mechanism do spinal fractures in patients with AS often result from?

Low-energy mechanism such as a fall from standing height

Why are people with AS more susceptible to fractures?

• Ossification of spinal ligaments

• Calcification of the annulus fibrosis

Why might it be hard to distinguish an acute fracture from a chronic inflammatory form of AS?

• Fracture may not be detectable with plain radiographs due to kyphotic deformity and distorted anatomy

• High riding shoulders can obscure the lower cervical spine

What is the incidence of spinal cord injury in AS patients?

Eleven times higher than the general population

What is the most frequent cause of death in AS?

Respiratory complications such as pneumonia

What percentage of the general population do minor bony malformations of all types occur in?

12%

What anatomical planes do congenital spinal deformities affect?

• Sagittal plane (kyphosis/lordosis)

• Coronal plane (scoliosis)

• Rotational

What three categories are origins of anomalies grouped into?

Malformation

• Failure of the embryologic differentiation or development of a specific anatomic structure, causing it to be absent or improperly formed before fetal period (week 8 onwards)

Disruption

• Subsequent destruction of an anatomic feature that formed normally during the embryonic period (weeks 3-8)

Deformation

• Alteration in the shape or structure of an individual vertebra or of the entire spine during the fetal or postnatal period, e.g. progressive, idiopathic scoliosis in patients with structurally normal spines at birth

What is the aetiology of congenital spinal deformities?

• Possibly multifactorial

• Inherited genetic susceptibility

• De novo alteration in molecular mechanisms (exposure to teratogens such as smoking)

What is occipitilisation?

Developmental anomaly where there is partial or complete fusion of the atlas to the occiput

What is the mechanism of cause for occipitalisation?

Failure of segmentation between the fourth occipital sclerotome (proatlas) and the first cervical sclerotome during embryonic development

What is the most common aspect of the atlas to assimilate into the occiput?

Anterior arch

What can occipitilisation be associated with?

• Atlantoaxial instability

• Basilar invagination

→Both can result in compression of the medullary cord

Define Klippel-Feil syndrome

Congenital fusion involving two segments, congenital block vertebrae or entire cervical spine

What causes congenital cervical fusion?

Failure of normal segmentation of cervical somites during weeks 3-8 of life

What is the classic clinical triad of Klippel-Feil syndrome?

• Low posterior hairline

• Short neck

• Limitation of neck motion (mostly lat bend and rotation)

What are the complaints of people with Klippel-Feil syndrome?

• Cosmesis of the neck or cosmesis resulting from associated anomalies (Sprengel deformity)

• Neck pain

• Radicular pain with or without weakness

• Slowly progressive or acute paraparesis or quadriparesis

What physical features are seen in KlippelFeil syndrome?

• Low posterior hairline

• Short neck

• Torticollis

• Restricted neck movements

What features is KlippelFeil syndrome associated with?

• Anomalies of the jaw

• Incomplete cleft of nasal cartilage

• Cleft palate

• Sprengels deformity

• Congenital deformities of external ear

• Cervical ribs

• Hypospadias

• Urinary tract anomalies

When is the typical onset of features in KlippelFeil syndrome?

3rd or 4th decade

In KlippelFeil syndrome, how does neurological involvement occur?

Through compression caused by laxity of the transverse ligament, alteration of course of vertebral artery, medullary compression of odontoid

What are the common anomalies associated with Killep-Feil syndrome (Decreasing order of frequency)

• Scoliosis

• Renal abnormalities]

• Sprengel deformity

• Deadness

• Congenital heart disease

• Ptosis

• Facial nerve palsy

• Hypoplastic thumb

• Upper extremity hypoplasia

Where is McRae’s line drawn and what does it assess?

• Drawn across the foramen magnum

• Odontoid process should not project above this

What headache symptomology is seen in occipitilisation?

• Dull ache

• Located over posterior two thirds of skull

• Precipitated by coughing or neck movements

• Long tract signs associated with dysfunction to the lateral corticospinal tract, that may be present in upper and lower extremities in the form of hyperrelexia, spasticity, hoffmans sign and babinski’s sign

• Cranial nerve findings including tinnitus, visual disturbances, lower cranial nerve palsies leading to dysphagia/dysarthria/downbeat nystagmus

• Horners syndrome

What is the management in occipitilisation?

• In patients with minor trauma or infection, can be treated conservatively with immobilisation in plaster, traction or cervical orthosis

• In patients with neuro involvement, cervical spine fusion or decompression is indicated

What should patients with congenital cervical fusion avoid?

Contact sports and activities that put them at risk for head trauma

What is the management of Klippel-Feil syndrome?

• Activity modification

• Bracing

• Traction

• Must consider spinal fusion if neuro lesion is present (avoid contact sports)

• Manual therapy contraindicated

Define Atlanto-Axial (AA) instability

Excessive movement at the junction between the atlas and axis due to bony or ligamentous abnormality

What can AA instability be caused by?

• Congenital conditions

• Trauma

• Degenerative changes due to inflammatory pannus of rheumatoid arthritis

• Infection

What two structures are often involved in AA instability?

• Transverse ligament

• Odontoid process

What structure is the primary restraint against anterior translation of C1 on C2?

Transverse ligament

What structure is the primary restraint against posterior translation of C1 on C2?

Odontoid process

State if the transverse ligament is intact in these distances:

<3.5mm

3.5-5mm

>5mm

Yes

No

No, alar ligaments also likely involved

What is vertical displacement of the atlas and what is the cause of it?

• Widening of the C1-2 facet joint

• Due to disruption of the alar ligament, superior longitudinal band of cruciate ligament, tectorial membrane or combination of these structures

What are the 4 types of atlantoaxial rotatory subluxation?

Type 1 (Stable)

• Simple rotary subluxation without anterior shift

• Odontoid acts as a pivot

Type 2 (Stable)

• Rotary displacement with anterior displacement of 3-5mm

• Lateral articular process act as pivot

Type 3(Not stable)

• Rotary displacement with anterior displacement of >5mm

Type 4 (Not stable)

• Rotary displacement with posterior displacement

How can AA instability cause neurological signs?

• Odontoid process or posterior arch of atlas can impinge on the spinal cord

• Motion of C1-2 segment can cause compression of nerve roots

What severe consequences are there for individuals with RA that have AA instability?

• Cervicomedullary compression

• Vertebral artery insufficiency

What is the primary cause of AA instability in individuals with down syndrome?

Laxity of transverse ligament

What congenital conditions other than down syndrome can cause AA instability?

• Osteogenesis imperfecta

• Neurofibromatosis

• Morquio syndrome

• Larsen syndrome

• SED congenita

• Chondrodysplasia punctata

• Metatropic dysplasia

• Kniest syndrome

What odontoid anomalies cause AA instability?

• Aplasia

• Hypoplasia

• Duplication

• Third condyle

• Os terminale

• Os odontoideum

What is down syndrome characterised by?

• Hypotonia

• Flat face

• Slanted palpebral fissures

• Small ears

What spinal abnormalities are seen in down syndrome?

• Incomplete fusion of vertebral arches of lower spine

• AA instability

• Abnormal odontoid process

• Hypoplastic posterior C1 arch

What is Grisel syndrome?

• Occurrence of atlantoaxial subluxation following inflammation of adjacent soft tissues after pharyngeal infection or surgical intervention

• Primarily seen in children aged 5-12

What is the common presenting feature of AA instability in the case of trauma?

Acute torticollis

What is the clinical presentation of AA instability?

• Pain (vague neck pain or headache)

• Torticollis

• Myelopathy

• Vascular occlusion

• Neurologic manifestations

• Occipital pain

• Vertigo

• Brainstem signs

• Lower cranial nerve palsies

• When infection present→ torticollis, tenderness over SP of C2

• Reduction in size of nasopharynx and increased nasal resonance due to forward displacement of arch of atlas

What is the management of AA instability?

• Unless spinal cord compression symptoms present, no treatment

• IF symptoms, Cervical spine stabilisation until surgery

• For those with down syndrome and ADI greater than 5mm, avoid sport, or activities with high risk flexion injury

• IF ADI>10mm or neuro findings develop, fusion recommended

What are the 4 grades of cervical spine injuries and what examples do they consist of?

Mild

• SJD, contusions, strains

Moderate

• Medical subluxations with no neuro involvement, sprains, sp fractures

Severe

• Stable fractures without neuro deficit

Dangerous

• Unstable fracture/dislocation, spinal cord/nerve root injury

Motor vehicle accidents account for what percentage of cervical spine injuries?

20%

Falls account for what percentage of cervical spine injuries?

50%

Women over the age of 80 account for what percentage of the 700,000 yearly spinal fractures?

40%

What is the M:F ratio of cervical spine injuries?

4:1

Sports related activites account for what percentage of spinal fractures?

15%

What percentage of cervical fractures have associated neurologic deficit?

40%

What are the possible neurological findings you can see with spinal fractures?

• Cranial nerve palsy

• Upper/lower limb symptoms/signs

• Long tract signs such as proprioception and vibration

Spinal shock

• Flaccidity

• Areflexia

• Fecal incontinence

• Priapism (Sustained incontinence)

• Loss of bulbocavernosus reflex

• Hypotension

• Paradoxical bradycardia

• Flushed, dry and warm peripheral skin

• Urinary retention

What are the two important things to consider in your history when looking at trauma?

The demographic and mechanism of trauma

What different aspects of mechanism of injury do you need to know?

• Direction

• Speed

• Stationary/moving

• Other possible injuries at the time

What should your clinical exam look like if you suspect cervical fracture?

• Observe for torticollis and limited ROM (important)

• Palpation from nuchal lines to T1, midline and laterally

• Gentle pressure on SP and TP’s

• Observe and palpate for deformities and step-offs

• Neuro exam

What form of imaging has a better sensitivity for detecting spinal injury, X-Ray or CT?

CT

• Plain film has sensitivity of 70%

• CT has sensitivity of 99%

What signs and symptoms does the NEXUS criteria state that allow you to clear suspected cervical spine injury?

• No posterior midline cervical spine tenderness present

• No evidence of intoxication present

• Normal level of alertness

• No focal neuro deficit present

• No painful distracting injury

• Able to rotate neck 45 degrees left and right

What are the cervical spine injuries in order of most to least unstable?

• Rupture of transverse ligament of atlas

• Burst fracture with posterior ligamentous disruption (flexion teardrop fracture)

• Bilateral facet dislocation

• Burst fracture without posterior ligamentous disruptiomn

• Hyperextension fracture dislocation

• Hangman fracture

• Fracture of dens

• Extension teardrop (stable in flexion)

• Jefferson fracture (burst fracture of ring of C1)

• Unilateral facet dislocation

• Anterior subluxation

• Simple wedge compression fracture without posterior disruption

• Fracture of posterior arch of C1

• SP fracture (clay shoveler fracture)

What are the cervical fractures that occur with a flexion mechanism?

• Simple wedge fracture

• Flexion teardrop fracture

• Anterior subluxation

• Bilateral facet dislocation

• Clay shoveler fracture

What is the most common cause of a simple wedge fracture?

• Osteoporosis

• Can be traumatic

What is the mechanism of injury in a simple wedge fracture?

• Longitudinal pull exerted on the nuchal ligament complex

• Anterior vertebral body compresses

• No posterior disruption

What is the mechanism of injury in a flexion teardrop fracture?

• Flexion with vertical axial compression causing fracture of anteroinferior aspect of vertebral body

• Significant posterior ligamentous disruption must occur

• Most common at C5/6

• Usually indicates spinal cord injury

When does anterior subluxation of the cervical spine occur?

• When posterior ligamentous complexes (nuchal ligament, capsular ligaments, ligamenta flava, posterior longitudinal ligament) rupture

What is the mechanism of injury for bilateral facet dislocation?

Significant degree flexion and distraction causing ligamentous disruption to extend anteriorly

• Extremely unstable condition

• 75% occur between C3 and C7

What is the mechanism of injury for clay shoveler fracture?

Abrupt neck flexion combined with a heavy upper body and lower neck muscular contraction, causing avulsion via the supraspinous ligament

What are cervical fracture occurs with a flexion and rotation mechanism?

Unilateral facet dislocation

What is the mechanism of injury for a Unilateral facet dislocation?

• Flexion and rotation

• Forces an inferior articular facet of an upper vertebra to pass superior and anterior to the superior articular facet of a lower vertebra

• Rests in the IVF

Is a unilateral facet dislocation a stable injury?

Yes, while the posterior ligament is disrupted, the vertebra are locked in place

What are the cervical fractures that occur with an extension mechanism?

• Hangman fracture

• Extension teardrop fracture

• Posterior arch of C1 fracture (Posterior neural arch fracture)

What change is there to C2 in a Hangman fracture?

Bilateral fracture through the pedicles due to hyperextension

Are there neural complications in a hangmans fracture?

Yes, when associated with a unilateral or bilateral facet dislocation

Is a hangmans fracture considered stable or unstable?

Unstable

Describe the Levine and Edwards classifications of Hangmans fractures?

Type 1

• <3mm displacement with no angulation of anterior aspect of fracture

Type 2

• Greater forward angulation than type 1

• Cervical traction with halo vest required

Type 3

• Severe angulation and/or facet dislocation

• Requires surgical restoration

What is the mechanism of injury in an extension teardrop fracture?

• Anterior longitudinal ligament pulls fragment away from inferior aspect of vertebra due to sudden hyperextension

• Causes a displaced anteroinferior bony fragment

• Common after diving accidents and tends to occur at C2

Is an extension teardrop fracture considered stable or unstable?

Usually stable, but if extreme is associated with central cord syndrome due to buckling of ligamenta flava into spinal canal

In Central cord syndrome, will you see more motor involvement in the upper limbs or lower limbs? What other signs will you see?

Upper limbs

Bladder dysfunction and variable sensory dysfunction

What is the mechanism of injury in a Posterior arch of C1 fracture (Posterior neural arch fracture)?

Head is hyperextended and posterior neural arch of C1 is compressed between the occiput and the spinous process of C2

Is Posterior neural arch fracture considered stable or unstable?

Stable, as transverse ligament and anterior arch of C1 are not involved

What is another possible differential to consider when you suspect a posterior neural arch fracture?

Jefferson fracture

What are the cervical fractures that occur with an compression mechanism?

• Jefferson fracture (burst fracture of ring of C1)

• Burst fracture of lower cervical vertebral body

What is the mechanism of injury in a Jefferson fracture?

• Compressive downward force transmitted evenly through occipital condyles to superior articular surfaces of lateral masses of C1

• This displaces masses laterally and causes fractures of anterior and posterior arches

• Possible disruption of transverse ligament (displacement of lateral masses is >6.9mm) (consider instability)

→ If less than 6.9mm, transverse ligament still intact and neurologic injury unlikely

Describe the 3 types of lateral displacement of C1

Type 1

• Intact transverse ligament

• ADI <3mm

• Lateral displacement <7mm

Type 2

• Transverse ligament torn

• ADI >3mm

• Lateral displacement <7mm

• Cord damage possible

• Fusion may be required

Type 3

• Lateral displacement >7mm

What is the management of the 3 types of lateral displacement of C1?

• Type 1 and 2 treated with cervical orthosis

• Type 3 may require internal fixation

What is the mechanism of injury in a burst fracture?

• Downward compressive force transmitted to lower levels in cervical spine causing cervical vertebra to shatter

• Posterior protrusion may extend into spinal canal, can be associated with anterior cord syndrome

• Internal fixation required if neurological deficit is present

Is a burst fracture considered stable or unstable?

Yes, in the absence of neurological deficit

What spinal tract is involved in anterior cord syndrome where there is complete motor paralysis below the level of the lesion?

Corticospinal tract

What spinal tract is involved in anterior cord syndrome where there is loss of pain and temperature at and below the level of injury?

Spinothalamic tract