Back pain is one of the most common health problems and is usually due to mechanical causes like muscle strains or disc issues. While the cause is often unknown, signs and symptoms like radiating leg pain help identify patients who may have a herniated disc compressing the nerve root. MRI is the best way to visualize disc damage, and treatment ranges from conservative options to surgery for severe or progressive cases. Most acute back pain resolves on its own, but recurrence after initial episodes is common.

1. Back Pain

2. DefinitionDefinition
 Back pain can be defined as pain of any natureBack pain can be defined as pain of any nature
felt in any region ranging from the thoracicfelt in any region ranging from the thoracic
spine to the pelvis.spine to the pelvis.
 Generally, back pain is classified as mechanicalGenerally, back pain is classified as mechanical
or non-mechanical and can be subdivided byor non-mechanical and can be subdivided by
regional involvementregional involvement

3. AetiologyAetiology
 There are numerous causes of back pain.There are numerous causes of back pain.
 Generally, pain can be attributed to:Generally, pain can be attributed to:
1.1. Nerve root compression and subsequentNerve root compression and subsequent
inflammationinflammation
2.2. Mechanical damage to and inflammation of spinalMechanical damage to and inflammation of spinal
componentscomponents
3.3. Degenerative and bony changesDegenerative and bony changes
4.4. Others eg. psychogenic and referred.Others eg. psychogenic and referred.
 It should be noted, in a large proportion ofIt should be noted, in a large proportion of
cases back pain is idiopathic.cases back pain is idiopathic.

4. Specific examplesSpecific examples
 Muscle spasms and strains (ligaments, muscles, tendons)Muscle spasms and strains (ligaments, muscles, tendons)
 Intervertebral disc prolapseIntervertebral disc prolapse
 OsteoarthritisOsteoarthritis
 Osteoporotic compression fracturesOsteoporotic compression fractures
 Traumatic injuryTraumatic injury
 FibromyalgiaFibromyalgia
 Ankylosing spondylitis and sacroiliitis.Ankylosing spondylitis and sacroiliitis.
 Spinal stenosis (narrowing of spinal canal)Spinal stenosis (narrowing of spinal canal)
 Lateral root stenosis (narrowing of root canal)Lateral root stenosis (narrowing of root canal)
 Spondylolysis (deficiency of pars intereticularis of neuralSpondylolysis (deficiency of pars intereticularis of neural
arch)arch)

5.  Spondylolisthesis (vertebral body slips forward)Spondylolisthesis (vertebral body slips forward)
 Rheumatic disorders eg. RA and polymyalgia rheumaticaRheumatic disorders eg. RA and polymyalgia rheumatica
 Paget’s diseasePaget’s disease
 Scoliosis – pain from osteoid osteoma of vertebralScoliosis – pain from osteoid osteoma of vertebral
pediclepedicle
 Referred pain eg. from chest, abdomen or pelvisReferred pain eg. from chest, abdomen or pelvis
 PregnancyPregnancy
 Poor posturePoor posture
 Lifestyle eg. smokingLifestyle eg. smoking

6. IncidenceIncidence
 Back pain is one of the mostBack pain is one of the most
common health problems incommon health problems in
the US and UK.the US and UK.
 It is estimated 50 to 80% ofIt is estimated 50 to 80% of
adults have experienced backadults have experienced back
pain at some point.pain at some point.
 In the UK, 7% of the adultIn the UK, 7% of the adult
population consult their GPpopulation consult their GP
with back pain each year, at awith back pain each year, at a
cost of £500 million and 80cost of £500 million and 80
million working days lost.million working days lost.

7. EpidemiologyEpidemiology
AgeAge
 Age of onset is spread relatively evenly from 16 years to the earlyAge of onset is spread relatively evenly from 16 years to the early
40s, gradually declines thereafter and is uncommon after the mid40s, gradually declines thereafter and is uncommon after the mid
fiftiesfifties
SexSex
 No difference in incidence between men and womenNo difference in incidence between men and women
Co-morbidityCo-morbidity
 Back pain is commonly associated with other conditions eg. OABack pain is commonly associated with other conditions eg. OA
OccupationOccupation
 It is generally thought back pain is more common in those withIt is generally thought back pain is more common in those with
manual occupations who undertake heavy liftingmanual occupations who undertake heavy lifting
AssociationsAssociations
 There is a strong association between smoking and back pain,There is a strong association between smoking and back pain,
possibly due to complex interaction of demographic variablespossibly due to complex interaction of demographic variables

8. Pathology of low back pain andPathology of low back pain and
sciaticasciatica
 Study by Kuslich et al. operated onStudy by Kuslich et al. operated on
patients undergoing decompressionpatients undergoing decompression
operations and stimulated variousoperations and stimulated various
tissues around the vertebrae usingtissues around the vertebrae using
mechanical force or electrical current.mechanical force or electrical current.
 They found sciatica can only beThey found sciatica can only be
produced by direct pressure orproduced by direct pressure or
stretch on the inflamed, stretched orstretch on the inflamed, stretched or
compressed nerve root. This maycompressed nerve root. This may
occur secondary to disc prolapseoccur secondary to disc prolapse
 The outer annulus of theThe outer annulus of the
intervertebral disc is the tissue ofintervertebral disc is the tissue of
origin in most cases of low backorigin in most cases of low back
pain.pain.
 In spite of what has been previouslyIn spite of what has been previously
suggested, muscle, fascia and bonesuggested, muscle, fascia and bone
were found to be quite insensitive.were found to be quite insensitive.

9. Clinical Features of a Disc ProlapseClinical Features of a Disc Prolapse
 Commonest levels to be affected are between L4/5 orCommonest levels to be affected are between L4/5 or
L5/S1L5/S1
 Muscular spasms can be profound , leading to aMuscular spasms can be profound , leading to a
scoliosis and restricted flexion.scoliosis and restricted flexion.
 Most patients report sharp, burning, stabbing painMost patients report sharp, burning, stabbing pain
radiating down the leg to the foot ie. sciatica.radiating down the leg to the foot ie. sciatica.
 Pain is intermittent but made worse by activity,Pain is intermittent but made worse by activity,
coughing, sneezing and straining.coughing, sneezing and straining.
 Paraesthesia and motor weakness can also occur – theirParaesthesia and motor weakness can also occur – their
distribution may allow the lesion to be localiseddistribution may allow the lesion to be localised

10.  Specific muscles can be assessedSpecific muscles can be assessed
for power to determine locationfor power to determine location
of the lesion eg. quadriceps areof the lesion eg. quadriceps are
innervated by L2, L3 and L4innervated by L2, L3 and L4
nerve roots. Reflexes shouldnerve roots. Reflexes should
also be tested.also be tested.
 If straight leg raising on theIf straight leg raising on the
unaffected side producesunaffected side produces
controlateral pain, this is highlycontrolateral pain, this is highly
suggestive of a disc prolapse.suggestive of a disc prolapse.
 A central herniated disc mayA central herniated disc may
compress nerve roots of thecompress nerve roots of the
cauda equina resulting incauda equina resulting in
bladder or bowel dysfunctionbladder or bowel dysfunction
(difficult urination or(difficult urination or
incontinence). This should beincontinence). This should be
dealt with as an emergency.dealt with as an emergency.

11. Natural HistoryNatural History
 Most acute episodes settle within 4-6 weeksMost acute episodes settle within 4-6 weeks
without any treatment.without any treatment.
 It is beneficial to provide symptomatic relief forIt is beneficial to provide symptomatic relief for
the first six weeks of symptoms.the first six weeks of symptoms.
 Involvement of the bladder, anal canal or anyInvolvement of the bladder, anal canal or any
other severe neurological deficit should be dealtother severe neurological deficit should be dealt
with as an emergency and treated immediately.with as an emergency and treated immediately.

12. InvestigationsInvestigations
 Plain radiographs of thePlain radiographs of the
lumbar spine are of limitedlumbar spine are of limited
use in the diagnosis of discuse in the diagnosis of disc
prolapse, but may be usedprolapse, but may be used
to exclude other pathologyto exclude other pathology
eg. fracture.eg. fracture.
 The gold standard forThe gold standard for
herniated disc imaging isherniated disc imaging is
MRI. This allowsMRI. This allows
visualization of discvisualization of disc
damage and should alwaysdamage and should always
be performed if surgery isbe performed if surgery is
contemplated.contemplated.

13. Differential DiagnosisDifferential Diagnosis
 Mechanical back pain:Mechanical back pain:
 Pain is usually restricted to the buttock and posterior thigh ie.Pain is usually restricted to the buttock and posterior thigh ie.
not sciatic distribution.not sciatic distribution.
 Pain is exacerbated during standing and twisting movements;Pain is exacerbated during standing and twisting movements;
pain from herniated disc is made worse by positions that putpain from herniated disc is made worse by positions that put
increased pressure on the annular fibres eg. sitting.increased pressure on the annular fibres eg. sitting.
 Any other condition causing compression of lumbarAny other condition causing compression of lumbar
nerve rootnerve root
 Lumbar spinal stenosisLumbar spinal stenosis
 SpondylolisthesisSpondylolisthesis
 TraumaTrauma
 Piriformis syndromePiriformis syndrome
 Spinal tumoursSpinal tumours

14. TreatmentTreatment
 Conservative: prevention is the best remedy – liftingConservative: prevention is the best remedy – lifting
and handling methods, bed rest, physiotherapy andand handling methods, bed rest, physiotherapy and
exerciseexercise
 Medical: analgesia, steroid or local anaestheticMedical: analgesia, steroid or local anaesthetic
injections.injections.
 Surgery is indicated forSurgery is indicated for
 Acute central disc prolapse with balder involvementAcute central disc prolapse with balder involvement
 Progressive neurological weakness despite bed restProgressive neurological weakness despite bed rest
 Unremitting pain with abnormal neurological signs despiteUnremitting pain with abnormal neurological signs despite
bed rest for 2-3 weeksbed rest for 2-3 weeks
 Marked muscle weaknessMarked muscle weakness
 Recurrent episodes of sciatica with only partial relief fromRecurrent episodes of sciatica with only partial relief from
conservative treatmentconservative treatment

15. SurgerySurgery
 Involves removal of the protruding material through aInvolves removal of the protruding material through a
laminotomy or partial laminectomy – may be combinedlaminotomy or partial laminectomy – may be combined
with fusion of affected segment.with fusion of affected segment.
 Percutaneous nucleotomy – contained disc isPercutaneous nucleotomy – contained disc is
decompressed by laser or instrumentation passed intodecompressed by laser or instrumentation passed into
the disc under X-ray controlthe disc under X-ray control
 Chemonucleolysis – chymopapin is injected into theChemonucleolysis – chymopapin is injected into the
disc space to dissolve the disc. High risk of anaphylaxis.disc space to dissolve the disc. High risk of anaphylaxis.

16. Laminotomy

17. PrognosisPrognosis
 Most acute episodes settle with bed rest only in 4-6Most acute episodes settle with bed rest only in 4-6
weeks.weeks.
 90% of cases don’t require surgery90% of cases don’t require surgery
 5% of people do go on to experience chronic severe,5% of people do go on to experience chronic severe,
incapacitating lower back painincapacitating lower back pain
 After successful laminotomy or laminectomy 80-85%After successful laminotomy or laminectomy 80-85%
of patients do extremely well and are able to return toof patients do extremely well and are able to return to
their job in 6 weeks.their job in 6 weeks.
 After one disc prolapse there is a statistically significantAfter one disc prolapse there is a statistically significant
increase in risk of a further prolapse.increase in risk of a further prolapse.

18. SummarySummary
 Back pain is extremely common.Back pain is extremely common.
 There are multiple causes – in most cases noThere are multiple causes – in most cases no
underlying pathology can be identified.underlying pathology can be identified.
 Of the large number of patients presenting withOf the large number of patients presenting with
back pain, the main role of the history andback pain, the main role of the history and
examination is to identify the small number whoexamination is to identify the small number who
have a serious or specific spinal disorder.have a serious or specific spinal disorder.