25-11-21 - Clinical Anatomy of the Back Flashcards
Learning outcomes
- Apply knowledge of anatomy to disorders of the back.
- Apply knowledge of anatomy to the clinical basis of back pain.
- Briefly describe the clinical features associated with common disorders of the back.
- Recall the red flag features of cauda equina syndrome.
- Compare and contrast the imaging modalities used to diagnose conditions of the back.
What are 2 ways cervical ligaments can become injured?
• Cervical ligament injuries can occur through:
1) Impact
2) Hyperflexion
What is spondylosis? Where is spondylosis common? What is the purpose of facet joints? What can cause facet joint syndrome? When is pain worse with facet joint syndrome?
- Spondylosis is an umbrella term used to describe pain from degenerative conditions of the back
- Spondylosis is common in cervical and lumbar regions where the joints become weak
- Facet joints (aka zygapophyseal joints) prevent excess rotation or lateral flexion of the vertebrae, with support from the ligamentum flavum which connects the laminae of vertebrae
- Facet joint syndrome can be caused by degenerative changes in the synovial joint or the ligamentum flavum
- Pain is worse on rotation or lateral flexion with facet joint syndrome
What is spondylolisthesis?
Where is this condition most common?
Where does the vertebrae usually slip?
What may there be impingement/compression of?
- Spondylolisthesis is the anterior slip of a vertebrae on the lower segments due to weakness of the ligamentum flavum
- This condition most commonly occurs in the L4/L5 vertebrae or the L5/S1 due to spondylosis
- The vertebrae usually slips to one side
- There may be impingement of the spinal nerve as it exits the intervertebral foramen
- There may also be compression on the spinal cord and cauda equina
A patient (woman) comes in with severe lower back pain, which came on all of a sudden. The pain radiates down both legs and the patient is having difficulty walking
Why do we ask about urinary and bowel incontinence during a history taking?
What might numbness around the perianal and buttocks indicate?
What 2 things may be found during a neurological examination?
- Urinary and bowel incontinence (unintentional passing of faeces/urine) may indicate problems with the S2, 23 and S4 spinal nerves
- Numbness around the perianal region and buttocks may be an indication of saddle anaesthesia (reduced sensation in area where would make contact with a saddle – affects S2, S3, S4, S5)
- During a neurological examination, we would look fpr saddle anaesthesia
- We may also look for loss of anal sphincter tone during a PR (rectal examination), which would affect S2, S3 and S4 spinal nerves
When assessing the patient, what are pros and cons of using:
• X-ray scan (plain film)
• Computer tomography scan (CT)
• Magnetic resonance imaging (MRI)
• Which scan is the best for this patient?
What is Cauda equina syndrome?
What is needed to treat this?
What 3 things can be caused by cauda equina syndrome?
What are degenerative causes of cauda equina syndrome?
What is a traumatic cause?
What is a malignant cause?
- Cauda equina syndrome is the collection of symptoms and signs that result from the severe compression of the descending lumber and the sacral nerve roots within the lumbar cistern
- A prompt diagnosis and decompression of the cauda equina is needed
• Cauda equina syndrome can cause:
1) Permanent incontinence (lack of control over urination or defecation)
2) Sexual dysfunction
3) Paraplegia (paralysis of lower part of body)
- Degenerative causes – lumbar disc herniation, spondylolisthesis
- Traumatic cause – vertebral fracture/dislocation
- Malignant – metastases (development of secondary malignant growth at a distance from the primary site of cancer)
What way do lumbar intervertebral discs usually herniate?
Why are herniated discs usually an emergency?
Where is pain caused by lumbar intervertebral disc herniation?
When is it worse?
Where else might pain occur?
- Lumbar IV discs usually herniate postero-laterally towards the intervertebral foramen due to the central position of the posterior longitudinal ligament
- Herniated discs are usually an emergency as there may be compression of the cauda equina (caudal equina syndrome) or spinal nerve compression if the herniation is above L1/l2
- Lumbar intervertebral disc herniation causes lower back pain, characterised by a dull ache that is worse with flexion
- There may also be sciatica, which is pain or paraesthesia (abnormal sensation e.g pins and needles) in the dermatomal distribution of the sciatic nerve (nerve roots L4 – S3) and the weakness of those myotomes
What are 4 degenerative changes caused by lumbar intervertebral disc herniation?
What is an age-related change?
What are 3 activities where lumbar intervertebral disc herniation is common?
• Degenerative changes:
1) Gelatinous nucleus pulposus (NP) replaced with fibrous tissue
2) Unable to bear compressive forces
3) Weight transferred to annulus fibrosus (AF) causing fissures over time (fibres break/separate)
4) Once fissure reaches the peripheries of the IV disc, there is risk of NP herniation
- Annular (ring shaped) tears occur when the water content declines with age, reducing the tension in the AF
- Lumbar intervertebral disc herniation is common in:
1) Jobs involving heavy lifting
2) Contact sports injuries
3) Trauma to the vertebral column
What is osteomyelitis?
What are 3 causes?
What are 3 ways it spreads?
What is discitis?
How is it similar to osteomyelitis?
When is discitis highly suspected?
What is the imaging method of choice to detect infections of the spine?
- Osteomyelitis is infection of the bone and bone marrow (vertebrae)
- 3 causes of osteomyelitis:
1) In all age groups, infection with staph aureus (bacteria)
2) In sickle cell disease – salmonella species (bacteria)
3) In Potts disease – pulmonary TB that has spread to vertebra
• 3 ways the infection spreads:
1) Blood stream (blood supply to spine)
2) Direct – from infection in nearby tissue e.g cellulitis (recall veins in the spine lack valves)
3) During operation or procedures on the spine (streptococcus species – skin commensal)
- Discitis infection of the intervertebral dis
- Discitis has a similar aetiology and pathophysiology to osteomyelitis of the vertebrae
- Discitis is highly suspected in intravenous drug uses with subacute back pain (days-weeks)
- MRI is the imaging method of choice for detecting infection of the spine
What is the nerve that innervates the trapezius?
What 3 things can injury of this nerve lead to?
What are 3 common causes of lower back pain in athletes?
• The spinal accessory nerve is a superficial nerve in the neck that innervates the trapezius (superficial muscle)
• Spinal accessory nerve injury (traumatic or iatrogenic – relating to illness) can cause instability in:
1) Neck joints
2) Scapular joints
3) Glenohumeral joint
• Common causes of lower back pain in athletes:
1) Sprain
• Ligament injury or strain
• Muscle or tendon injury
• Especially common in sports that involve hyperextension of the back
• E.g gymnastics, cricket, pole vault, weightlifting
2) Spondylosis and spondylolisthesis of the vertebrae (vertebrae slips out of position)
3) Disc herniation
Where can back pain also be referred from?
What are 3 examples?
• Back pain can also be referred from intra-abdominal structures:
1) Peptic ulcer disease
2) Abdominal aortic aneurysm (bulge in blood vessel caused by weakness in vessel wall)
3) Pancreatitis
Winking owl sign
