Back pain Flashcards
Functions of the spine
Locomotor: capable of being both rigid and mobile
Bony armour: protects the spinal cord
Neurological: spinal cord transmission of signals between brain and periphery
Key MSK structures of the spine
- Spinal column consisting of
A) 24 vetebrae (7 cervical, 12 thoracic, 5 lumbar)
B) intervertebral discs (act as shock absorbers, allow segmentation and multi-directional movement)
C) facet joints (small synovial joints at posterior spinal column linking each vertebra) - Muscles- move the spine
Where do you see normal kyphosis and normal lordosis in the spine
Cervical spine, lumbar spine- normal lordosis
Thoracic spine- normal kyphosis
Key neurological structures structures of spine
Spinal cord- transmission of signals from brain, ends at L2 spinal level
Nerve roots- exit spinal cord bilaterally
Cauda equina- nerve bundle
Movements of the spine
Flexion (forward bend) vs extension (backwards bend)
Lateral flexion (side bend)
Rotation (twist)
How common is back pain
Very common, >50% of people will experience an episode
Is acute back pain self limiting.
Usually yes, most better in a few days, 96% better in 6 weeks
What time duration of back pain qualifies for chronic back pain. How common is it and name a common risk factor
12 weeks
Also very common
Caused by sedentary lifestyle
Mechanical back pain exacerbating/ relieving factors?
Reproduced or worse with movement
Better or not present at rest
Common causes of mechanical back pain
Muscular tension (chronic poor posture, weak muscles)
Acute muscle sprain, spasm
Degenerative disc disease
Osteoarthritis of facet joints
What is sciatica?
What is the typical cause of sciatica?
What determines the location of pain of sciatica?
Pain radiating down one leg (may accompany mechanical back pain
Typically caused by disc herniation (nucleus pulposus herniates through annulus fibrosus) contacting the exiting lumbar nerve root
Location of pain is determined by level of herniated disc
Serious causes of back pain
Tumor- metastatic, myeloma
Infection- discitis, vertebral osteomyelitis, paraspinal abscess (microbiology- staphylococcus, streptococcus, TB)
Inflammatory spondyloarthropathy- ankylosing spondylitis, psoriatic arthritis, IBS-associated
Fracture- traumatic/ atraumatic (osteoarthritis)
Large disc prolapse causing neurological compromise
Referred pain- pancreas, kidneys, aortic aneurysm
Red flag symptoms of back pain
Pain at night or increased pain when supine
Constant or progressive pain
Thoracic pain
Weight loss
Previous malignancy
Fever/night sweats
Immunosuppressed
Bladder or bowel disturbance (Sphincter dysfunction)
Leg weakness or sensory loss
Age <20 or >55 yrs
What syndrome associated with back pain is a neurological emergency and why?
Cauda equina syndrome
Untreated, will lead to permanent lower limb paralysis and incontinence
Symptoms/ signs of Cauda equina syndrome
Saddle parasthesia
Loss of anal tone or PR
Radicular leg pain
Ankle jerks may be absent
Bladder/ bowel incontinence
Cauda equina syndrome investigation
Urgent MRI lumbar spine
Causes of Cauda equina syndrome
Large disc herniation
Bony mets/ myeloma
TB
Paraspinal abscess
Treatment of Cauda equina syndrome
According to cause, may require urgent surgery
Back pain: history-taking- what is included?
Site & pattern
Character (e.g. aching, throbbing, burning, electricity)
Onset
Prolonged morning stiffness
Exacerbating/relieving factors
Effect of movement vs. inactivity
Radiation (e.g. sciatica)
Buttock pain
Leg weakness
Sensory loss/paraesthesia
Lower limb claudication ((peripheral vascular disease, spinal stenosis))
What is involved in examination of the spine?
Look
Feel
Move
Straight leg raise (SLR) ((lie flat, lift leg straight up, if sciatica, at some point symptoms reproduced))
Lower limb neurological exam
General exam (signs of malignancy, AAA)
What investigations are carried out for back pain?
In the absence of red flags, investigation usually not required
Do not routinely arrange a spinal X-ray or other imaging to diagnose non-specific low back pain in primary care
Arrange review if symptoms persist or worsen after 3–4 weeks and reassess for an underlying cause
Treatment for low back pain without red flags
Time
Analgesia (NSAIDs e.g. ibuprofen, paracetamol, codeine)
AVOID bed rest: keep moving
Physiotherapy
-Soft tissue work
-Corrective exercises esp. core e.g. side plank, bird dog.
What types of investigations are used for back pain?
Blood tests, radiographs (Xray), CT, MRI
What can different blood results indicate with regards to back pain?
Pros and cons of radiography, CT, MRI
Radiographs (X-rays)
-poor sensitivity, radiation
-cheap, widely available
Computed tomography (CT) scans:
-good for bony pathology, larger radiation dose
Magnetic resonance imaging (MRI):
-Best visualization of soft tissue structures like tendons and ligaments
-Best for spinal imaging: can see spinal cord and exiting nerve roots
-Expensive and time-consuming
What does this image show?
Possible cause?
“Wedge fracture”/ vertebral collapse
Can be caused by osteoporotic weakening
25 year old man originally from Nepal
Worsening low back pain for 8 weeks
Worse in the morning but present at all times
Weight loss
Night sweats
Differential?
TB! (cancer less likely because young)
Nepal is an indicator
In what age groups are herniated discs most common
30-50
Natural history for herniated disc
Good outlook
Normally spontaneous improvement, although typically slower than for low back pain alone
Treatment of herniated disc
- Conservative as for LBP without sciatica
-Analgesia especially NSAIDs
-Physiotherapy to improve core strength and treat associated muscle spasm - Nerve root injection (local anaesthetic and glucocorticoid)
- Surgery if neurological compromise or symptoms persist (Trials of surgery vs conservative Rx show no long term advance for surgery)
Can slipped discs resolve spontaneously
Yes, sequential MRI studies show that herniated portion of the disc tends to regress with time with partial or complete resolution in two thirds of cases after six months.
What is inflammatory spondyloarthropathy? Give examples
Group of immune-mediated inflammatory diseases
Ankylosing spondylitis (AS)((loss of spinal movements, severe spinal deformity)), psoriatic arthritis and inflammatory bowel disease (IBD)
What joins are affected in inflammatory spondyloarthropathy?
Primarily inflammation of the spine (spondylitis) and sacro-iliac joints (sacro-iliitis)
Peripheral joints, esp. tendon insertions (entheses), can also be affected- this can cause dactylitis/ sauasage fingers
Extra-articular manifestations of inflammatory spondyloarthropathy?
Anterior uveitis (iritis) – ocular inflammation
Apical lung fibrosis
Aortitis/aortic regurgitation
Amyloidosis – due to chronically serum amyloid A (SAA) depositing in organs
Pathophysiology of ankylosing spondylitis
Characterised by enthesitis (inflammation of the entheses- sites where tendon and ligaments join to bone)
Large genetic component
Many genetic variants associated with the disease (polygenic)
HLA-B27 is the strongest genetic risk factor
HLA = a region on chromosome 6 encoding MHC molecules
HLA-B27 is a class 1 MHC molecule
Cells present peptides to CD8 T cells in association with MHC class 1 molecules
HLA-B27 +ve in 90% of AS patients versus ~10% in general population
Used as a diagnostic biomarker but HLA-B27 +ve alone does not equal AS
Cytokines play important roles in pathogenesis
tumour necrosis factor alpha (TNF-alpha)
interleukin-17 (IL-17)
interleukin-23 (IL23)
Aberrant peptide processing pathways (aminopeptidases) in the endoplasmic reticulum
What can you see in imaging of sacroiliac joint in ankylosing spondylitis
Irregular SI joint, increased whitening on either side
Imaging in ankylosing spondylitis:
Sacro-iliitis on MRI
Natural history of untreated Ankylosing Spondylitis
Spinal enthesitis
->
Bridging syndesmophytes
(new bone growth between adjacent vertebra)
->
Spinal fusion
Spinal MRI in Ankylosing Spondylitis-Advantage over Xray?
What is an MRI sign of AS on MRI?
MRI can detect spinal inflammation before X-rays changes develop
In image we see “Shiny corners” sign at L4, L5 and S1
Management of ankylosing spondylitis
1) Physiotherapy and a life-long regular exercise programme
2) Pharmacological
1st line: non-steroidal anti-inflammatory drugs (NSAIDs)
-e.g. ibuprofen, naproxen, diclofenac
-Mechanism: NSAIDs inhibit cyclooxygenase 1 and 2 (COX1 and 2)
-Risks: peptic ulcer, renal, asthma exacerbation, ↑ atherothrombosis risk
-Selective COX2 inhibitors (e.g. celecoxib) reduce GI ulcer risk
2nd line: ‘Biological’ therapies
Therapeutic monoclonal antibodies (mAbs) targeting specific molecules
Use if inadequate disease control after trying 2 NSAIDs
Anti-TNF-alpha (e.g. adalimumab, certolizumab, infliximab, golimumab)
Anti-IL17 (e.g. secukinumab)
