Medical Bites
Back Pain
ECINSW
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Back Pain
Lecture to go with Medical Bites
Back Pain
Red Flags for diagnoses not to miss
 Acute on chronic pain associated with increasing
weakness (CES)
 Weakness or sensory symptoms associated with
systemic symptoms, such as fever or nausea,
implies an infective cause
 Neurological symptoms and signs of any kind
without a clear explanation
 Warfarin use and back pain is retroperitoneal
haemorrhage until proven otherwise
Back Pain
Red Flags for diagnoses not to miss
 A past medical history of cancer associated with
new back pain equals malignant metastases
until proven otherwise
 New atrial fibrillation associated with new back
pain, especially in as yet anticoagulated
patients, equals ischaemia of the spinal cord
Back Pain
Objectives
 To be able to assess, diagnose and treat serious
and common presentations of back pain
 To be aware of the risks and red flags
associated with back pain
Back Pain
Definitions
 Pain described by the patient or clinician as
arising from the back.
Back Pain
Risks
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Rupture Abdominal Aortic Aneurysm (AAA)
Renal colic
Pneumonia
Retroperitoneal Haemorrhage
Remember the Drug seeker, but don’t make it
life’s ambition
 Spine, infection, malignancy and fracture
 Cauda equina( the major back emergency)
Back Pain
Recognition of illness
 Always need to assess for
 Potential airway compromise
 Potential respiratory failure
 Potential circulatory failure
 Potential neurological failure
 Vitally important to identify when any patient
approaches the end of their ability to
compensate for illness or injury
 Just because a clinical variable is normal
does not mean that it still will be in 5 minutes
time
Back Pain
Recognition of illness
 Clinical signs of potential ABCDE system failure
are similar whatever the underlying process
 These signs reflect failing respiratory,
cardiovascular and neurological systems
 We therefore always need to assess ABCDE to
identify failure in one system, AND the effect of
failure on other systems
 If we treat immediately, we prevent further harm
Back Pain
Immediate actions
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Global overview of patient
Speak to patient
Formally examine ABCDE
Treat problems in systems - find an airway
problem, treat it immediately…
 Resuscitate - aim to reverse immediate
problems and halt deterioration - NOT to aim for
normal physiological values
Back Pain
History – important points
 Traumatic?
 Onset and course, is it…
 Persistent (malignancy, infection)
 Acute (musculoskeletal)
 Acute on chronic (pathological)
 Chronic (degenerative)
 Urinary / sexual dysfunction
 Neurological symptoms (cauda equina, nerve
route compression)
Back Pain
History – important points
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Unexplained fevers (infection)
Unexplained weight loss (malignancy)
Past back injuries or problems (musculoskeletal)
Past medical problems - malignancy,
immunocompetency (metastases)
 Social circumstances (disposition)
Back Pain
The pain
 Onset
 rapid with musculoskeletal
 slow with infection and malignancy
 Associations - immediate and delayed
 Exacerbation
 musculoskeletal improves with rest or lying
still
 renal colic tends to make you move around
 relief
Back Pain
The pain
 Referral patterns
 dermatomal patterns
 remember there are referral patterns with
musculoskeletal pathology which is nondermatomal
 Current analgesia taken, frequency, regularity
and doses
Back pain
Examination
 Global overview
 Behaviour
 Position e.g. lying straight and immobile with
musculoskeletal pain
 Moving around e.g. with renal colic
 Leaking or ruptured AAA can appear in many
guises depending on the extent of the leak but
may look very unwell
 Neurological examination lower limbs
 Straight leg raise (SLR) - positive test is pain to
the foot on extending the straight leg, implies
nerve root lesion
Back Pain
Investigations
 Often none required, apart from where there is
indication from history or examination that there
is serious / systemic illness associated with pain
Bedside
 Random blood glucose for diabetes (infection
neuropathy risk)
 ECG for atrial fibrillation (embolic risk leading to
spinal ischaemia)
Back Pain
Investigations
Bedside
 Urinalysis for blood (serious loin pain without
haematuria may still be renal colic but AAA must
be considered until excluded by ultrasound or
CT
Laboratory
 FBC - Hb (anaemia from leaking AAA,
malignancy), WCC (infection)
 EUC - renal function, metabolic disturbances
 Blood cultures - if febrile
Back Pain
Investigations
Imaging
 A number of ED physicians / surgeons can do
ultrasound scans to investigate for AAA
 Attempt to organise this investigation rapidly
when there is any suspicion of a leaking
aneurysm (i.e. any older person with abdominal
pain when another convincing diagnosis is not
immediately apparent)
Back Pain
Investigations
Imaging
 Lumbar spine or other X-rays may be helpful,
but where there is acute atraumatic or low
impact traumatic musculoskeletal pain
presenting for the first time in the ambulatory
patient, they very rarely are
 In fact there is little correlation between X-ray
findings and pain scores
Back Pain
Investigations
Imaging
 CT scans are often performed for back pain,
but when they are not specifically targeted at
investigating serious pathology such as
malignancy / metastases or fractures (where
mechanism or clinical picture or plain films
suggests fracture) they very rarely change
management
Back Pain
Investigations
Imaging
 Minor disc lesions and degenerative changes
which do not necessarily correlate with
symptoms are often disturbing and
misinterpreted by clinicians and patients
 Consider….
 If you are doing a CT scan of the back you
are giving a large radiation load
Back Pain
Investigations
Imaging
 Particularly in young and women patients you
must have a clear set of differential diagnoses
and treatment plans in mind, depending on
your result
 If you cannot do this then refer on for more
senior consultation
Back Pain
Investigations
Imaging
 MRI may be performed as an emergency
investigation where there is suspicion of
cauda equina syndrome (the major
diagnosis not to miss), in order to diagnose
spinal cord compression
 This is done urgently and often requires a
number of phone calls or transport out of
regular hours to another facility
 MRI for other indications is not an
emergency Investigation
Back Pain
Diagnoses not to miss
 Cauda equina syndrome (CES) - a
neurological emergency
 Fractures of any kind, particularly unstable
ones
 Infections of the spine, often at the extremes
of age
 Inflammatory conditions of the spinal cord
 Nerve root compressions
 Blood supply compromise e.g. secondary to
AF, emboli
Back Pain
Red Flags for diagnoses not to miss
 Acute on chronic pain associated with increasing
weakness (CES)
 Weakness or sensory symptoms associated with
systemic symptoms, such as fever or nausea,
implies an infective cause
 Neurological symptoms and signs of any kind
without a clear explanation
 Warfarin use and back pain is retroperitoneal
haemorrhage until proven otherwise
Back Pain
Red Flags for diagnoses not to miss
 A past medical history of cancer associated with
new back pain equals malignant metastases
until proven otherwise
 New atrial fibrillation associated with new back
pain, especially in as yet anticoagulated
patients, equals ischaemia of the spinal cord
Back Pain
Specifics
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Cauda equina syndrome (CES)
Infection
Nerve root compression
Inflammatory and ischaemic
Musculoskeletal
 Fractures
 Muscular pain
Back Pain
Specifics
Cauda Equina syndrome (CES)
 Low back pain
 Unilateral or usually bilateral sciatica
 Saddle sensory disturbances
 Bladder and bowel dysfunction
 Variable lower extremity motor and sensory loss
Back Pain
CES - pathophysiology
 Compression of susceptible cauda equina nerve
roots
 May be caused by…
 Trauma
 Lumbar disc disease
 Abscess
 Spinal anesthesia
Back Pain
CES - pathophysiology
 Compression of susceptible cauda equina nerve
roots
 May be caused by…
 Tumour, either metastatic or CNS primary
 Late-stage ankylosing spondylitis
 Idiopathic
 Inferior vena cava thrombosis
 Lymphoma or sarcoidosis
Back Pain
CES - history
 Low back pain
 Acute or chronic radiating pain
 Unilateral or bilateral lower extremity motor and
/or sensory abnormality
 Bowel and / or bladder dysfunction; symptoms
may be described within a spectrum from
hesitancy to incontinence, which is overflow from
an atonic bladder
 Saddle (perineal) anaesthesia
Back Pain
CES - examination
 Local lumbar tenderness to palpation or
percussion
 Reduced reflexes (not increased reflexes which
implies an upper motor neurone lesion in the
spinal cord)
 Sensory abnormalities over the perineal area or
lower extremities
 Light touch in the perineal area should be
tested
 Muscle weakness may be present in muscles
supplied by affected roots
Back Pain
CES - examination
 Muscle wasting may occur if CES is chronic
 Poor anal sphincter tone is characteristic of CES
 Babinski sign or other signs of upper motor
neuron involvement, suggests a diagnosis other
than CES, such as an intrinsic cord lesion or
external compression
 Anaesthetic areas may show skin breakdown
 A large residual post-void urine as measured by
catheterisation
Back Pain
CES - investigation
Bedside
 Urinalysis for infection
Laboratory
 FBC
 WCC - investigating for infection
 Hb - investigating for malignancy
Imaging
 Key investigations are imaging
Back Pain
CES - investigation
Imaging
 Plain radiography usually not helpful, however
may be used to look for destructive lesions, discspace narrowing, or spondylolysis (degeneration
of an articulating part of a vertebra)
 CT with / without contrast - lumbar myelogram
followed by CT
 MRI - currently considered a requirement in
suspected CES, but improved CT scanners may
disprove this
Back Pain
CES - treatment
 If suspect CES consult neurosurgical early for
directed investigations and ongoing
management
 Early steroids may be used
 Surgical decompression may be appropriate,
depending on aetiology
 Depending on local institutional practice surgery
may be performed early, intermediate or late
 Specific treatments such as antibiotics depend
on suspected causes
Back Pain
Infection
 Pyogenic vertebral osteomyelitis is the most
commonly encountered form of vertebral
infection
 Aetiology may be from
 direct open spinal trauma
 infections in adjacent structures
 hematogenous spread of bacteria
 can occur postoperatively
 Left untreated, it can lead to permanent
neurologic deficits, significant spinal deformity,
or death
Back Pain
Infection – risk factors
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Advanced age
Intravenous drug use
Congenital immunosuppression
Long-term systemic administration of steroids
Diabetes mellitus
Organ transplantation
Malnutrition
Cancer
Back Pain
Infection - history
 Back pain which is increasing, and lasting for
weeks to months
 Fever is present in around 50% of patients
Back Pain
Infection - examination
 Local tenderness, which may be initially mild
 Neurologic signs are usually late and occur due
to bony destruction
 Decreased range of motion
 Radicular (nerve root) signs and paralysis
suggest epidural abscess
Back Pain
Infection - examination
 Sensory examination includes
 sensory level
 heat / cold
 pain
 reflexes
 rectal tone
 perianal sensation
Back Pain
Infection - investigation
Bedside
 Urinalysis - infection, diabetes, blood
Laboratory
 VBG - metabolic status
 FBC - WCC as sign of infection
 Other inflammatory markers are often performed
(ESR, CRP) but do not rule in or rule out
infection, and are often a waste of time
 Blood cultures may be of benefit
 Clinical suspicion mandates further testing with
imaging
Back Pain
Infection - investigation
Imaging
 Plain radiography will show late destructive
lesions
 CT with and without contrast
 MRI if available and most likely after CT
 Technetium uptake scans for activity of
osteomyelitis
Back Pain
Infection - treatment
 Assessment using ABCDE, as infective back
pain may represent an underlying systemic
sepsis or may lead to this
 Keep tuberculosis in mind, particularly in at-risk
groups
 Initially broad spectrum antibiotics are used,
however consult early and widely, including
microbiology
Back Pain
Infection - treatment
 Adequate analgesia – often requiring IV opiates
 The premorbid state which allows spinal
infection implies the patient is at risk of
numerous pathologies, therefore a full medical
workup is required but is likely to occur over time
as an in-patient
Back Pain
Nerve root compression
 This back pain diagnosis is one of the more
clear cut, given that the history refers to both
motor and sensory issues in a nerve root
distribution, with concurrent reflex abnormalities
 Key point - signs must fit the nerve root
distribution, and there must not be signs or
symptoms suggestive of other red flag
pathologies, such as infection or cauda equina
syndrome
 The key to nerve root distributions is dermatomal
pattern, and which roots are involved in various
muscle groups (myotomes) and reflexes
Back Pain
Nerve root compression - history
 Pain as initial complaint, then varying degrees of
weakness as a later symptom
 May be history of trauma, and often of chronic
back pain
 Specifically question to elicit symptoms of
infection or malignancy, including fevers, weight
loss and general malaise
 Pain medication history is important, to gauge
both pain severity and potential for dependence
after prolonged use
Back Pain
Nerve root compression - examination
 Lower limb for obvious asymmetry of colour and
skin texture, to detect other system involvement
such as Circulation
 Full neurological examination of lower limb *(see
practical skills)
 Straight leg raise (SLR), is positive when the leg
is elevated with the patient supine and pain
radiates to the foot; this implies a nerve root
lesion
Back Pain
Nerve root compression - examination
 Sensory landmarks
 C6 at the thumb
 T4 at the nipple
 T10 at the umbilicus
 L5 at the top of the foot
 S1 over the sole of the foot
 S2-S4 at the perineum
 (see dermatome chart)
Back Pain
Nerve root compression
Back Pain
Nerve root compression - investigation
Bedside
 Urinalysis - infection, diabetes, blood
Laboratory
 As indicated by history and examination,
however none may be indicated
Imaging
 Plain X-rays are usually of no use but be guided
by the patient history
Back Pain
Nerve root compression - investigation
Imaging
 CT scan may be of use but it will confirm nerve
root compressive elements
 MRI may be required
 Importantly, often none of the above are urgent if
no red flags are present
Back Pain
Nerve root compression - management
 Early, effective analgesia is the key to treating
any back pain
 IV opiates if needed
 ‘Triple analgesia’
 Paracetamol 1g 6 hourly PO
 Ibuprofen 400mg 6-8 hourly PO
 Oxycodone 5mg 6 hourly PO
Back Pain
Nerve root compression - management
 Together with analgesia and reassurance, early
referral for assessment and specialist
management of nerve root symptoms is the
mainstay of treatment
 For significant symptoms such as debilitating
weakness, or unrelieved pain, admission may be
very rarely required
Back Pain
Inflammatory and ischaemic
 These are very important diagnoses and often
very difficult to appreciate early
 the key is to respond to positive findings and
indicators in your history and examination by
appropriate investigations, and thereafter by
referral
 If you have a positive finding do not ignore it
because it does not fit your diagnosis.
 If it doesn’t fit it may be spurious but it may also
be part of a complex presentation; always ask
senior ED and refer if possible
Back Pain
The commonest diagnosis
 Musculoskeletal mechanical back pain
 Logically this is divided into…
 Fractures
 Muscular pain
Back Pain
Fractures
 The diagnosis of fractures starts with
suspicion…
 when there is a mechanism which could
transmit significant load to the back, including
compressive forces such as a heavy object
hitting the top of the head and transmitting
energy down the spine
Back Pain
Fractures - examination
 Primary survey, ABCDE approach and
immediate resuscitation in systems, including
oxygen, IV analgesia and fluids via x2 large bore
cannulae (see serious trauma lecture)
 Call for help early - senior ED
 Thorough top to toe examination (secondary
survey)
 Full neurological examination
 This will then direct you, given the background
level of suspicion to appropriate imaging,
remembering Nexus / Canadian C-spine rules
Back Pain
Fractures - examination
Nexus rules
If the patient is alert, and there is…
 No neck pain
 No posterior midline cervical spine tenderness
present
 No evidence of intoxication present
 A normal level of alertness
 No focal neurologic deficit present
 No painful distracting injury
You do not have to image this patient
Back Pain
Fractures - examination
Canadian C-spine rule
 Patient alert (GCS 15)
 Not intoxicated
 No distracting injury (e.g. long bone fracture, large
laceration)
 The patient is not high risk (age >65 years or dangerous
mechanism or paraesthesia in extremities)
 A low risk factor that allows safe assessment of range of
motion exists. This includes simple rear end motor
vehicle collision, seated position in the ED, ambulation at
any time post-trauma, delayed onset of neck pain, and
the absence of midline cervical spine tenderness
 The patient is able to actively rotate their neck 45
degrees left and right
Back Pain
Fractures - management
 Any patient in which a spinal fracture is
suspected must be kept immobilised and other
suspicious areas imaged, i.e. when there is one
spinal fracture there is a 10% likelihood of
another being present
 Immobilisation means a C-collar needs to be
applied and remain in place, and the patient log
rolled when transport or movement required
(see practical skills)
Back Pain
Fractures - management
 Analgesia, using morphine IV titrated to pain
 Antiemetics, traditionally metclopramide 10mg,
and more recently ondansetron 4 mg IV
 Steroids may be requested by neurosurgeons
managing the patient
Back Pain
Muscular – introduction
 A number of both senior and junior doctors
dislike seeing back pain patients; this is because
of the perceived difficulties in their management
 As with all our difficult ED patients, when a
system is applied it assists the resolution of the
patient’s problems, and the dilemma of the
clinical staff.
 The key to adequate treatment of back pain is
getting the confidence of the patient early
Back Pain
Muscular - history
 Often there is no history of major or even minor
trauma, but sudden onset after, for example,
‘bending to pick up a pen’
 There is usually back-straining activity in the last
two weeks, or there is a history of a backintensive occupation such as bricklayer or
mother of young children
 Red flags, as mentioned earlier, need to be
carefully excluded
Back Pain
Muscular - examination
 ABCDE
 Full neurological examination including SLR
 Full examination looking for other systems
pathology as indicated
 Examination may be normal, but limited due to
pain; if this is the case you have given enough
analgesia to relieve resting discomfort
Back Pain
Muscular - investigation
 None
Back Pain
Muscular - management
 Early analgesia, in adequate amounts, is the
mainstay of treatment
 See triple therapy described earlier
 Ensure you give a clear explanation that the
medications in triple analgesia therapy are…
 …metabolised separately, so no risk of
overdose
 …multiplicative rather than additive, so give
added analgesia
 …taken regularly rather than PRN, to
ensure adequate ‘levels of pain relief’
Back Pain
Muscular - management
 Start on full dose triple therapy, and give clear
instructions about titrating analgesia down
 To get the patients confidence you must get their
comfort and then you will get cooperation
 If pain is severe, control initially with morphine
and then introduce oral medications early if you
intend to discharge the patient (you do!)
 The principle is the oral medications take over
from the morphine and discharge can be
facilitated
Back Pain
Muscular - management
 If you incrementally increase / escalate pain
medications because each one does not work
individually, the patient will remain longer in the
ED, you will lose their confidence and make
discharge harder
 Therefore - titrate morphine 5 mg + 2.5mg
IV…etc until pain relief achieved
 Depending on amount required after 2 hours
add in oral paracetamol 1g and oxycodone (5mg
for milder pain, 10mg for more severe)
 When patient has had some food give some
ibuprofen 400mg
Back Pain
Muscular - management
 In this way, after 3-4 hours, and even in patients
with severe back pain, you may have someone
who is able to be discharged
 For less severe pain, commence with either
ibuprofen, paracetamol or oxycodone depending
on the level, or potentially a combination of two
agents rather than three
 Ensure, however, that the patient has good
analgesia, rather than worry about too much
analgesia
 Discuss ongoing requirements and the
pathophysiology of the pain with the patient
Back Pain
Muscular - management
 Explain that the severity of the pain often does
not reflect the amount of pathology or damage,
and that the spasm is a protective mechanism
 If discharging the patient, you need to know full
social circumstances
 Advise that manipulation should not be done
acutely and may not help in the long term, but
good advice regarding back management from
physiotherapists and osteopaths may
 Remember a number of patients will attend other
clinicians and rather than disregarding this you
should advise how best to use them
Back Pain
Summary
 Give analgesia in adequate amounts, titrate in a
timely fashion
 Keep red flags in mind, and if the history and
examination does not fit then be suspicious
 Drug seeking is a possibility, but be careful with
this as a diagnosis (e.g. IVDUs get spinal
infections). It is better to give an opiate addicted
person one episode of medication than to deny
a person in pain the analgesia they really need
 We need to engender Comfort, Confidence and
Cooperation
Back Pain
Summary
 The patient who cannot be discharged due to
pain or social circumstances should get
admission; but you will need to negotiate local
custom whether it is appropriately medical (more
common in elderly), orthopaedic or
neurosurgical as the admitting team. (They are
all wankers anyway!)
 When referring be sure you have adequately
trialed analgesia, have a clear clinical picture
and can present the patient concisely to the ED
senior or other clinician