clinical anatomy of the vertebral column Flashcards
What does the vertebral column consist of
33 vertebrae in total, 23 cartilaginous disks between them.
What are the functions of the vertebral column?
Upright position, assists with balance, shock absorbent and facilitates movement e.g. flexion and extension. Protects vertebral canal housing spinal cord.
How are the curves of the vertebral column seen?
sagittal plane
What type of joint is an intervertebral disc?
Fibrocartilaginous joint
What is the structure of the intervertebral disc?
Consists of an outer annulus fibrosus and inner nucleus pulposus
What keeps the intervertebral discs in place?
Anterior and posterior longitudinal ligaments form boundaries and provide stability. Anterior stronger. Anterior prevents hyperextension, posterior prevents hyperflexion.
Why do we “shrink” in height we get old?
Joint space narrowing, loss of muscle mass and tone, reduced volume of intravertebral disc
Why do the intervertebral discs not heal properly after injury?
Avascular and low cell density
what are the articulation points?
what are articular surfaces covered in?
Superior articular facets articulate with vertebrae above. Inferior with vertebrae below. Indirectly articulate via intervertebral discs.
Articular surfaces covered in hyaline cartilage.
important ligaments and what are they between?
: Ligamentum flavum – between lamina. Interspinous and supraspinous – spinous processes.
how to insert a lumbar puncture?
what are the layers the needle goes through?
causes of back pain
sinrim
why is back pain important?
Estimated that between 60 – 80% of the population have back pain at some point in their lives.
Very common presentation in both GP and ED.
Some presentations are chronic, some are medical emergencies.
HERNIATED INTERVERTEBRAL DISK
-> degenerative changes
-> age related changes
causes
most likely location
what is sciatica and how to test for it
->Gelatinous NP replaced with fibrous tissue
Unable to bear compressive forces.
Weight transferred to AF causing fissures over time.
Once fissure reaches peripheries of the IV disc, risk of NP herniation.
=> Annular tears occur when the water content declines with age, reducing tension in the AF.
Flexion of the spine (Bending over)
Jobs involving heavy lifting
Contact sport injuries
Trauma to the vertebral column
Mostly occur in lumbar region (L4-L5 or L5-S1 level)
Compress L5 or S1 part of sciatic nerve sciatica
Useful test: straight leg raise
Lower back pain (dull ache, worse with flexion)
Sciatica – pain or paraesthesia in the dermatomal distribution of sciatic nerve (nerve roots L4-S3) and weakness of those myotomes
Usually postero-lateral IV disc herniation, impinging on spinal nerve root
what type of herniation is often an emergency and why
Posterior herniation of IV disc is often an emergency: cauda equine syndrome or spinal cord compression (if above L1/L2
how to diagnose for herniated intervertebral disk and how to treat
Diagnosis (Dx)?
Clinical findings
MRI
Treatment (Tx)?
Analgesia, nonsteroidal anti-inflammatory drug
Keep active rather than bed rest
Avoid activities which aggregate symptoms (e.g. lifting)
Physiotherapy
Steroid injection may help
Surgery is the last resort
what is kyphosis
causes/ consequences
what scan shows osteoporosis
Excessive convex curvature of the spine, especially the thoracic region
DEXA scan (bone densitometry) showed evidence of osteoporosis
DEXA Scan (Bone Densitometry): This is a test used to measure bone mineral density (BMD) and assess bone strength.
Bones are the reservoir for calcium (Q11)
Calcium deficiency –> bones appear porous –> bone mineral density decreased on DEXA (bone mass decreased) –> bone becomes weak –> fractures easily
Causes with age include: degenerative disc disease, muscle loss, wedge/ compression fractures.
Consequences – further reduce mobility, increased risk of falls and therefore #
what to look for on scans => AP view and lateral view
Look for The owl’s two eyes (pedicles) and beak (spinous process); shape and contours
On AP film: A winking owl (single or bilateral pedicle disruption) suggests possible fracture.
On the lateral film a compression fracture (wedge shape vertebral body). These are common in osteoporosis, after the bone has become brittle.
Other causes of winking owl sign
Bone metastasis
TB
Neurofibromatosis
Congenital hypoplasia of pedicle
vertebral fractures
what does the range look like
when to suspect
what type of treatment
Range from compression fracture in elderly patient to burst fracture in young patient
When to suspect:
History of significant trauma relative to patient’s age
Sudden severe central spinal pain which is relieved on lying down
Structural deformity of the spine
Vertebral tenderness
Treatment depends on the type of fracture and its stability
SPONDYLOSIS & FACET JOINT SYNDROME
what is it?
what region is it in?
what can it be associated with?
when is pain worse?
Osteoarthritis (Degeneration) of the spine / facet joint
Common in cervical and lumbar regions.
May be associated with bony spurs (osteophyte)
Pain is worse on rotation or lateral flexion.
what is SPONDYLOLYSIS
what can it progress to?
Stress fracture through the pars interarticularis of the lumbar vertebrae
Can progress to spondylolisthesis
what is spondylolisthesis?
what region?
what could occur?
what might it compress?
Anterior slip of a vertebra on the lower segment due to weakness of ligamentum flavum or fracture of pedicle.
Usually slips towards one side
Commonly L4/L5 or L5/S1
There may be impingement of the spinal nerve as it exits through the intervertebral foramen
May compress on the spinal cord or cauda equina
what is spina bifida?
Sclerotome does not develop/fuse properly (Neural tube defect)
Exact cause not known
Folate (folic acid) deficiency, some medications (eg valproic acid
ABNORMAL NUMBER of VERTEBRAE
Sacralisation of L5
Lumbarisation of S1
what is ANKYLOSING SPONDYLITIS
what does it eventually cause?
An inflammatory disease of the joints and ligaments of the spine
Eventually causes ankylosis of vertebral and sacroiliac joints (Bamboo spine).
Patient is admitted with severe lower back pain, which came on all of a sudden. The pain is radiating down both legs and she is having difficulty walking.
How will you assess this patient systematically?
History vs neurological exam
which imaging technique?
History
PQRST: Pain at rest.
Low back pain, dull in nature.
Radiates down both buttocks, thighs and lower legs (radicular pain).
Acute onset (hours-days)
Urinary incontinence (S2-4)? Are you aware when your bladder feels full (urinary retention)?
Bowel incontinence (S2-4)?
Numbness around perianal region + buttocks? (saddle anaesthesia - S2-4)
Neurological Examination
Local tenderness? (lumbar spine)
Loss of sensation? (touch, pain, temperature) in dermatomes supplied by lumbar + sacral nerve roots.
Lower limb muscle weakness? (unilateral or paraplegia)
Loss of knee and ankle reflex (L3-4 and S1)
Saddle anaesthesia? (loss of sensation)
Loss of anal sphincter tone? (on PR exam) – S2-4
which imaging technique?
what is CAUDA EQUINA SYNDROME?
causes:
-degenrative
-traumatic
-infective
-malignant
symptoms
SPINE
Summary of Cauda Equina Syndrome (CES)
Definition:
Cauda Equina Syndrome is caused by severe compression of the lumbar and sacral nerve roots in the lumbar cistern, leading to serious neurological symptoms.
Key Risks:
- Permanent incontinence
- Sexual dysfunction
- Paraplegia
Importance:
Prompt diagnosis and surgical decompression are crucial to prevent lasting damage.
Causes (Aetiology):
1. Degenerative:
- Lumbar disc herniation (most common)
- Spondylolisthesis
2. Traumatic:
- Vertebral fracture or dislocation
- Epidural hematoma (trauma or post-surgery)
3. Infective:
- Epidural abscess
- Tuberculosis
4. Malignant:
- Metastases
- Primary CNS malignancies
cancers of spine
what is more common than primary cancer?
what are Common cancers that metastasis to spine?
Metastasis to spine is much more common than primary cancer
Common cancers that metastasis to spine:
Prostate
Breast
Lung
Renal
what is Osteomyelitis
types of infections
How do they spread?
infection of the bone and bone marrow (vertebra)
In all age groups infection with staphylococcus aureus (bacteria)
In sickle cell disease salmonella spp (bacteria)
Pott’s disease = Pulmonary tuberculosis that has spread to the vertebra (uncommon)
Blood stream (recall blood supply to spine)
Direct (from infection in nearby tissue e.g. cellulitis. Recall veins lack valves in the spine)
During operation or procedures on the spine (streptococcus species – skin commensal)
What is Discitis?
aetiology and pathophysiology ?
when to have a high suspicion?
infection of the intervertebral disc
Similar aetiology and pathophysiology to osteomyelitis of the vertebra.
Have a high suspicion of discitis in intravenous drug users with subacute back pain (days-weeks)
how to detect infection of the spine
MRI
what is this?
cause
ODONTOID PEG FRACTURE (C2).
Odontoid (peg) view plain film.
Lateral CT.
Caused by sudden severe flexion.
what is this?
cause
JEFFERSON FRACTURE (C1).
Caused by axial loading i.e. falling on head.
Atlas compressed between occiput and C2 with fracture of the lamina and pedicles.
what is this and what is it associated with?
FACET JOINT DISLOCATION (Example C4-C5)
These are rotational injuries, rarely occurring in isolation.
Associated with significant ligament injury, therefore unstable.
what is this?
what was it historically caused by/ how about now?
HANGMANS FRACTURE (C2)
Hyperextension leading to pedicle fracture.
Historically caused by hanging. In modern times seen in patient’s who have struck their head on the steering wheel during an RTC.
whiplash injury - what does it tear?
What are the risks and considerations of C-Spine immobilization in the Emergency Department?
True C-Spine Injury is Rare: While cervical spine injuries are uncommon, many patients arrive immobilized as a precaution.
Risks of Immobilization:
Raised Intracranial Pressure (ICP): Tight collars may restrict venous drainage from the head.
Pain: Discomfort from prolonged immobilization can cause distress.
Tissue Ischaemia/Pressure Sores: Prolonged pressure from collars can damage skin and underlying tissue.
Impaired Ventilation: Restriction of neck and chest movement can interfere with breathing.
