Neurosurgery Flashcards
List 8 red flags for back pain?
- Age: >60 or <20 years old
- Pain not improved by rest
- Pain that wakes the patient up at night
- Urinary retention/incontinence and faecal incontinence
- Saddle anaesthesia
- History of malignancy
- Unexplained weight loss.
- Fever, immunosuppression or IV drug abuse
List the ligaments of the spine from superficial to deep
supraspinous ligament
interspinal ligament
ligamentum flavum
posterior longitudinal ligament
anterior longitudinal ligament
Explain what a radiculopathy is and radiculopathy vs radicular pain?
- A radiculopathy is a conduction block in the axons of a spinal nerve or its roots, with impact on motor axons causing weakness and on sensory axons causing paraesthesia and/ or anaesthesia
There is a distinction between radiculopathy versus radicular pain: - Radiculopathy = a state of neurological loss and may or may not be associated with radicular pain
- Radicular pain = pain deriving from damage or irritation of the spinal nerve tissue, particularly the dorsal root ganglion
Causes of radiculopathy?
- Intervertebral disc prolapse: the lumbar spine is predominantly affected by repeated minor stresses that predispose to rupture of the annulus fibrosus and sequestration of disc material (the nucleus pulposus)
- Degenerative diseases of the spine: leading to neuroforaminal or spinal canal stenosis, the cervical spine is the most mobile segment of the spine and degenerative change is a normal part of the ageing process
- Fracture: either trauma or pathological
- Malignancy: most commonly metastatic
- Infection: such as extradural abscesses, osteomyelitis (most commonly TB), or herpes zoster
Clinical features of a radiculopathy?
- Sensory symptoms in the corresponding demeratome and weakness in the corresponding myotome
- Sensory features are paraesthesia and numbness and motor features are weakness
- Radicular pain is often also present, typically described as a burning, deep, strap-like, or narrow pain, it is not uncommon for radicular pain to be intermittent
- Important to ask about red flag symptoms for cauda equina
Management of a radiculopathy?
- Definitive long term management depends on the underlying cause
- In general the only condition that requires emergency surgical treatment is cauda equina syndrome
- Most IV disc prolapses can be managed non-operatively, but indications for surgical treatment include unremitting pain despite non-surgical management, progressive weakness, and new or progressive myelopathy (compression of the spinal cord)
- Symptomatic management is with analgesia, amitriptyline is usually first line or pregabalin and gabapentin as alternatives, if the patient suffers from muscle spasms these can be managed with benzodiazepines or baclofen, physiotherapy is an important part of management
What is the cauda equina and what is cauda equina syndrome?
- This is a surgical emergency caused by compression of the cauda equina
- The spinal cord ends at L1-L2
- The cauda equina is a bundle of nerves situated inferior to the spinal cord
- Cauda equina contains motor and sensory fibres to the lower limbs, motor innervation to the anal sphincters and parasympathetic innervation for the bladder
The spinal cord ends at
L1-L2
Causes of cauda equina syndrome? peak age of onset?
- Peak onset between 40-50 years
- Most common cause is disc herniation
- Other causes include trauma, neoplasms, infection, chronic spinal inflammation or iatrogenic e.g. haematoma secondary to spinal anaesthesia
Clinical features of cauda equina?
- Reduced lower limb sensation
- Bladder or bowel dysfunction
- Lower limb weakness
- Severe back pain
- Impotence
- Saddle paraesthesia and anaesthesia
- Need to do a PR exam to assess for reduced anal tone
- Post void bladder scan to assess urinary retention
- Full peripheral neurological examination including upper limbs is required to look for spinal pathologies higher up along the spine than cauda equina
Investigations for cauda equina?
- Emergency lumbar-sacral spine MRI
Management and prognosis of cauda equina?
- Neurosurgical decompression
- Prognosis is variable depending on aetiology and time from symptom onset to surgery
What is lumbar spinal stenosis?
- Narrowing of the spinal canal which compresses the lowest most spinal cord, conus medullaris and nerve roots leading to symptoms of neurogenic claudication
- Mainly occurs in patients older than 50 yo
Causes of lumbar spinal stenosis?
- Hypertrophy of facet joints and ligamentum flavum
- Protruding intervertebral discs
- Spondylolisthesis
Clinical features of lumbar spinal stenosis?
- Insidious and progressive over many months or years
- Unilateral or bilateral hip, buttock or lower extremity pain or burning sensation precipitated by standing or back extension and relieved by sitting, lumbar flexion or walking uphill
- Anthropoid posture (flexion of the waist)
- Neurogenic intermittent claudication: leg weakness, tingling and numbness accompanied by paraesthesia
Neurogenic vs vascular claudication?
- Neurogenic is dermatomal, variable amount of exercise illicit pain, can come on with prolonged standing at rest (vascular does not)
- When resting it takes a while to resolve, whereas vascular immediately resolves
- Burning pain in neurogenic vs cramping in vascular
- Peripheral pulses are normal in neurogenic but diminished or absent in vascular
- Neurogenic claudication is relieved on walking uphill whereas vascular is not
Investigations for lumbar spinal stenosis?
- Neurogenic claudication is often a clinical diagnosis but can be confirmed with MRI lumbosacral spine
Management of lumbar spinal stenosis?
- Conservative treatment first off (physio and analgesia)
- If symptoms worsen/ intolerable surgery can be done
What is cervical spondylosis?
Degenerative arthritic process of cervical spine and affecting intervertebral discs and zygapophyseal joints
Will either present as a radiculopathy or myelopathy
Different surgeries for it
Myelopathy vs radiculopathy?
Myelopathy – compressing on spinal cord itself – upper motor neuron signs
Radiculopathy – compressing the spinal nerves or their roots – lower motor neuron signs
What is degenerative cervical myelopathy? Why is it importantn?
- Spinal cord compression in the cervical region
- Causes UMN signs more prominent in the lower limbs
- Occurs in the elderly and causes a deterioration in a patient’s gait and thus is an important cause of falls in the elderly
Features of degenerative cervical myelopathy?
Progressive symptoms:
* Imbalance and disturbance of gaits
* Clumsy hands e.g. difficulty with buttons, or holding fork or tingling in fingertips
* Urinary or faecal incontinence (rare)
* Pain in a non-dermatomal distribution
* Legs jump at night due to hyperreflexia
On examination:
* UMN signs
* Weakness, hyperreflexia and spasticity
* Positive babinksi
* Loss of finger dexterity
Investigation for degenerative cervical myelopathy
MRI cervical spine
Management of degenerative cervical myelopathy?
- Early treatment = best recovery but most patients present too late
- Decompressive surgery is best, this prevents deterioration but does not improve symptoms
Describe anterior cord compression syndrome?
- Cord infarction by area of anterior spinal artery
- Loss of pain and temperature below level but preserved vibration and proprioception
- ie. You lose the spinothalamic which is ventral but keep the DCML as its dorsal
- also keep your corticospinals which are dorsal
Describe complete cord transection syndrome?
- All motor and sensory modalities below lesion
- Initially flaccid areflexic paralysis (spinal shock) but then UMN signs will appear
Describe brown sequard syndrome?
- Penetrating injury probably
- Ipsilateral UMN paralysis and loss of proprioception and vibration (because it crosses over at the medulla)
- Contralateral loss of pain and temperature (because spinothalamic crosses over at the spinal cord)
Describe central cord syndrome?
- Acute extension injury to already stenotic neck or syringomyelia or tumour
- Predominantly bilateral upper limb weakness > lower limbs
- Capelike spinothalamic sensory loss
- Dorsal columns preserved
The incidence of metastatic neoplasm is ______
metastates appear as ___________
the most common sites are _________
- The incidence of metastatic neoplasms in the brain is much higher than that of a primary cerebral neoplasm
- The common appearance of metastatic brain tumours is multiple, well-delineated spherical nodules that are randomly distributed
- The two most common primary sites are the lung and breast but any malignant tumours can metastasise to the brain
List some categories of brain tumours
gliomas
tumours of neuronal cell types
tumours arising from mesoderm
tumours of nerve sheath
germ cell tumours
pituitary gland tumours
Describe astrocytomas?
- These are gliomas that arise from astrocytes
- They are histologically graded from grade I-IV
- Grade I astrocytomas grow very slowly over many years while grade IV cause death within several months
What is a glioblastoma multiforme?
grade 4 astrocytoma - v aggressive
What is the most common glial tumour?
glioblastoma multiforme
Describe oligodendrogliomas?
- These are gliomas that arise from oligodendrocytes
- They grow very slowly over several decades and calcification is common
Describe tumours of neuronal cell type and different types?
- Fully differentiated neurons can neither multiply nor give rise to neoplasms
- Tumours of this type are therefore derived from primitive nerve precursors (blast cells) and seen in infancy and childhood before completion of differentiation
- Depending on their site of origin they are given different names (but the tumour is mainly composed of the same cells which are blast cells- blast cells are basically a precursor to mature neurons)
Medulloblastoma
* Tumour arising from cerebellum
Retinoblastoma
* Tumour arising from the retina
Neuroblastoma and Ganglioneuroma
* These are tumours that arise from sympathetic ganglia
* In ganglioneuromas the tumour is derived from blast cells but as the tumour grows the neurons actually mature
Describe menigiomas?
arise from arachnoid granulations most commonly adjacent to venous sinuses
slow growing and essentially benign
can occassionally arise in the spine