Spinal Disorders Flashcards
Describe the atlas
C1 - ring shaped
Has anterior and posterior arch fusing to lateral masses
No body or spinous process
Foramen transversarium has vertebral arteries in
Describe the axis
Has body and odontoid process that projects anteriorly
What are some features of cervical vertebrae?
Uncinate processes - bony process of superolateral aspects of C3-7 which resist lateral flexion
Uncovertebral joint - uncinate process and superior vertebrae
Spinous process
What are features of thoracic spine?
Heart shaped body, small spinal canal, ribs articulate with transverse process and ribs makes the thoracic spine stiffer
What are features of lumbar spine?
Kidney shaped bodies, transmits body weight to sacrum, no costal facets and width increases inferiorly
What are the features of the sacral vertebrae?
Fuse and progressively become smaller forming the triangular shape
Transmits weight to pelvis
Divided into 3 zones - lateral, intermediate and medial zones
What are some spinal ligaments?
Anterior and posterior atlanto-occipital membrane, transverse ligament, cruciate, apical, alar, anterior longitudinal, posterior longitudinal, ligamentum flavum and supraspinous ligament
Describe the atlanto-occipital and atlanto-axial joints?
First one allows flexion, extension and some lateral flexion
Atlanto-axial is median pivot joint
Describe the intervertebral discs
Located C2-3 and L5-S1
Has nucleus pulposus, annulus fibrosus and end plates - diffusion of nutrients to bone
What is the three column theory?
Anterior - anterior longitudinal ligament, anterior of annulus fibrosis and vertebral body
Middle - posterior longitudinal, posterior annulus fibrosis and vertebral body
Posterior - osseous and ligamentous structures posterior
Stability depends on 2 of these being intact
How many spinal nerves are there?
31 pairs
8 cervical, 12 thoracic, 5 lumbar, 5 sacral, 1 coccygeal
What are the main reflexes of the body?
Bicep, supinator, triceps, abdominal, cremasteric, knee, ankle, anal cutaneous and bulbocavernous
When can loss of bulbocavernous reflex be seen?
In spinal shock, conus medullaris and cauda equina lesions
What tracts control sensation?
Dorsal column - fine touch, joint position, vibration and proprioception
Lateral spinothalamic tract - pain + temp.
Anterior spinothalamic tract - light crude touch
Describe the notochord in embryology
Neural plate formed from ectoderm then neural groove to neural fold
This closes to form neural tube - takes 28 days
Tube gives rise to brain and spinal cord
Notochord - mesoderm forms bones of spine
Describe the anterior neuropore
Closes at 24 days
Failure to close results in anencephaly which is most common brain defect
Describe the posterior neuropore
Closes at 26-28 days
Failure to close results in spinal bifida
What can identify neural tube defects in high risk mothers?
Alpha fetoprotein and acetylcholinesterase from amniocentesis
What is spinal bifida?
Birth defect where there is incomplete closure of spine and membrane surrounding spinal cord
What are the risk factors of spinal bifida?
Low levels of folic acid before and after early pregnancy
FH
Diabetes and obesity
Anti-seizure drugs - sodium valproate
What are the types of spinal bifida?
Spinal bifida aperta - includes meningocele and myelomeningocele
Spinal bifida occulta - closed
Mainly in lumbar region but can be cervical
What is the clinical picture of spinal bifida?
Back swelling, low back motor deficit, sensory deficit, sphincter disturbance and associated back + lower limb deformities
What are the differences between meningocele and myelomeningocele?
Meningocele - covered by normal skin and contains CSF, is translucent, no neurological deficit
Myelomeningocele - sac is usually membranous, contains CSF and neural tissue, trans opaque, neurological deficit and sphincter deficit. Also associated to HCP
What is the treatment for spinal bifida?
Myelomeningocele - primary surgical closure
Intra uterine myelomeningocele repair (IUMR)
What is tethered cord syndrome?
Inelastic anchoring of the caudal spinal cord by abnormally thick or fatty filum terminale
Results in lumbosacral spinal cord being stretched and elongated
Presents with neurological, urological and orthopaedic signs
What could cause a spinal infection?
Pyogenic vertebral osteomyelitis and discitis
Granulomatous infections
Epidural infections
Postoperative infections
Describe pyogenic vertebral osteomyelitis and discitis
Discitis arises from hematogenous spread
Involve mainly the lumbar spine then thoracic then cervical being less
Most common - Staph aureus and streptococcus
What are the clinical symptoms and signs of pyogenic vertebral osteomyelitis and discitis?
Axial pain is most common and fever
Neurological changes in some patients - radicular numbness and muscle weakness
What are the investigations for pyogenic vertebral osteomyelitis?
WCC may increase, ESR, CRP is elevated, blood cultures, and urinalysis
Neuroimaging - X ray, CT and MRI
What is the treatment for pyogenic vertebral osteomyelitis?
Fist line - broad spectrum IV antibiotics for 6-8 weeks
Immobilization for reducing pain and stabilises spine
Surgery needed if meds fail, neurological deterioration and spinal instability
What are the risk factors for postoperative infections?
Increased age, obesity, diabetes, tobacco use, poor nutrition, prolonged surgical time and placement of instrument
What is post operative infections associated with?
Longer hospital stays
Higher complication rates
Increased mortality
How is post operative infections prevented?
Prophylactic antibiotics
If significant blood loss or gross contamination then intraoperative antibiotics
What is the treatment for postoperative infections?
Open irrigation and debridement
IV antibiotics for 6 weeks and oral after
What are the types of spinal cord tumours?
Extradural
Intradural extramedullary
Intramedullary
What is the imaging used for spinal cord tumours?
Pain X ray and CT
MRI is gold standard
What is the treatment of spinal cord tumours?
Surgical excision, biopsy and RT + chemo
What are spinal emergencies?
Spinal epidural compression
Cauda equina and conus syndromes
What are the causes of spinal hematomas?
Usually no factor identified
Anticoagulant therapy and vascular malformations
Trauma
Describe spinal hematomas
Subdural, epidural, subarachnoid (can extend the whole length), intramedullary haemorrhage
Typically localised dorsally to spinal cord
What are the clinical signs and symptoms of spinal hematomas?
Depends on location and extent of haemorrhage - motor weakness, sensory and reflex deficits and acute bladder/bowel dysfunction
Epidural and subdural - knife like pain
Meningitis like symptoms for subarachnoid
What is the imaging and treatment for spinal hematomas?
MRI is gold standard
Coagulopathy and surgical decompression
Laminectomy
What is cauda equina syndrome?
Surgical emergency that results from compressive, ischaemic and or inflammatory neuropathy of multiple lumbar and sacral nerve roots in lumbar spinal canal
What is he aetiology of cauda equina syndrome?
Trauma, haemorrhage, inflammatory disease, infection, degenerative spine disease and spine tumours
How does cauda equina syndrome present?
Leg pain, weakness, anaesthesia, saddle anaesthesia, bladder/bowel/ sexual dysfunction, decreased anal tone and absence of ankle reflex
What are the types of cauda equina syndrome?
Incomplete - loss of urgency and decreased urinary sensation without incontinence of retention
Complete - urinary and bowel retention or incontinence
What is the imaging and treatment for cauda equina syndrome?
MRI is gold standard
Treatment - surgical decompression within 24 hrs
What is a primary spinal cord injury?
Trauma results in immediate death of local cells
1 - direct damage to cell bodies and/or neuronal processes
2 - damage to spinal axons
What is secondary spinal cord injury?
Inflammation
Vascular events
Chronic phase of injury - demyelination and scar formation
What are the vascular events which happen in spinal cord injury?
Damage to endothelial cells of local blood vessels so impaired blood flow - ischaemia
Impaired autoregulation and vasospasm at site - ischaemia
Neurogenic shock, bradycardia and hypotension
Influx of inflammatory cells so more inflammation and secondary tissue damage
What is the definition of spinal shock?
Transient loss of neurological function below level of injury - flaccid paralysis and areflexia
Hypotension - shock
Duration is 72 hours but persists
What are the multiple factors causing spinal shock?
Interruption of sympathetic
Loss of vascular tone - bradycardia
Relative hypovolemia - skeletal muscle paralysis
True hypovolemia - blood loss
What is resolution of spinal shock first recognised by?
Return of the bulbocavernous reflex
Describe a complete spinal cord injury
Complete loss of motor and sensory function below the level of injury in absence of spinal shock
Poor prognosis
Describe incomplete spinal cord injury
Any residual motor or sensory function below level of injury
Sacral sparing, voluntary anal sphincter contraction or voluntary toe flexion
Describe central cord injury
Incomplete - most common
Usually results from hyperextension injury in older patients with pre-existing stenosis
Can result in cord contusion
Associated with cervical fracture/ dislocation and traumatic cervical disc herniation
What is the clinical symptoms of central cord syndrome?
Motor - weakness in UL more than LL
Sensory - loss below level of injury
Urine retention
Recovery is usually incomplete - LL first
What is anterior cord syndrome?
Cord infarction in the territory supplied by anterior spinal artery
Can result from occlusion of anterior spinal artery or cord compression
What is the presentation of anterior cord syndrome?
Paraplegia or quadriplegia
Dissociated sensory loss below lesion - loss of pain and temp. with preservation of 2 point discrimination, joint position and deep pressure
What does Brown Sequard Syndrome manifest with?
Ipsilateral loss of joint position, vibration loss and discrimination, also spastic paresis below level of injury
Contralateral loss of pain and temp. one level below lesion
What is primary and secondary assessment?
Primary - ATLS, airway, breathing, circulation and immobilisation
Secondary - GCS, identify axial skeleton fractures, pelvis fractures and appendicular skeleton
What imaging is used for spinal cord injury?
X ray
CT
MRI
What are indications for early decompression?
Incomplete spinal cord injury
Patients with progressive neurological deterioration
Describe occipital condyle fracture
Rare and usually stable
Due to direct blow to head
Presents with loss of consciousness, cranio-cervical pain and rarely lower cranial nerve deficits
Describe atlanto-occipital dislocation
Is common in children
Mechanism - hyperextension, distraction and rotation
Typically instant fatal injury and most have neurological deficits
Describe fracture of the atlas
Can be of posterior/ anterior arch, both with intact or disrupted ligament, and lateral mass fractures
Usually neurologically intact
Describe a fracture of the axis
Can be of the odontoid process, traumatic spondylolisthesis of axis and fractures of body
Describe subaxial cervical spine fractures
Ligamentous or osseous
Can be unilateral (displacement less than 25%), bilateral (more than 50%), tear drop (have neurological deficit) and burst fractures
Describe thorco-lumbar spine injuries
Thorco-lumbar junction is most frequently affected segment then lumbar and thoracic segments
Can be compression, burst, seat belt and fracture dislocations
Describe sacral spinal injuries
Zone 1 - neurological injuries, L5 or sciatic nerve damage
2 - higher incidence of neurological deficit but no sphincter involvement
3 - highest rate of neurological damage as nearer central canal
What surgical management of spine fractures?
Occipital condyle avulsion fractures, altanto-occipital dislocation, more than 5mm C1-2 displacement, neurological deficits, biomechanical instability and non union after 12 weeks
