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Mechanical Low Back
Injuries
An Integrated Approach ofFunctional Movement
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Objectives
To identify the underlying causes andmechanisms of mechanical low back pain
To understand some of the physical,biomechanical and psychosocial impairments
/ approaches associated with mechanical lowback pain
To integrate the approaches into a clinicalmodel and incorporate treatment strategiesinto the approach
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Epidemiology
Leading cause ofdisability in those underthe age of 45
3rd major cause ofdisability in generalfollowing heart diseaseand arthritis
About 70% of all adultshave low back pain(LBP) at some time intheir life
Most episodes of LBPresolve in 2-3 months(80-90%)
Recurrence rates areabout 50% in thefollowing 12 months
5-10% of people with
LBP develop chronicLBP (>3 months)
(Mannon et al, 2002; OSullivan, 2000)
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Epidemiology (contd)
Upto 85% of low back clients cannot begiven a definitive diagnosis
It is assumed that these injuries are dueto (1) musculoligamentous injuries or (2)degenerative changes
(Mannon et al, 2001)
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Causes of Low Back
PainRheumatologic
Endocrine /
MetabolicNeoplastic Disease
Vascular /
Hematologic
Infections
Referred Pain
PsychologicalMechanical
(Swenson et al, 1998)
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Mechanical Low Back
PainMechanical Low Back Paincan bedefined as pain that appears to have
been caused by a mechanical event(eg. Lifting, twisting, etc), and isaggravated by movement
(Gallagher, 2002)
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Mechanical Causes of
LBPFacet
Disc
Paraspinal MusclesInstability
Ligaments
Sacroiliac JointSpondylolysis / spondylolisthesis
Spinal stenosis
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Facet Joints
Degeneration of facet joints as a cause of lowback pain was first postulated in 1933
Theory continues to be controversialSuggested that accounts for upto 15-20% ofclients with low back pain
Nocioceptive nerve fibres have beenidentified in facet-joint capsules and insynovial and pericapsular tissue
(Hanley et al, 1999;Swenson,1998)
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Intervertebral Disc
Easily imaged on MRI; however degeneration andprotrusion may be seen in upto 64% of asymptomaticadults
Innervation of the disc has been well characterized
The meningeal nerve branches supply the PLL &outer layers of the annulus fibrosus (AF)
The outer 1/3 of the AF is innervated with paintransmitting free nerve endings
Evidence suggests that severely degenerated discshave more extensive innervation than normal discs
(Hanley et al,1999)
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Disc (contd)
Two most common causes of disc pain
are annulus fibrosus tearsand disc
herniationHerniated discs cause compression onpain sensitive structures such as the
outer 1/3 of the annulus, PLL, anteriordura, nerve root & sinuvertebral nerve
(Hanley et al, 1999)
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Ligaments
6 main ligaments Anterior longitudinal ligament (ALL),Posterior longitudinal ligament (PLL), Interspinous,Supraspinous, Ligamentum flavum & Intertransverse
Ligamentumflavumnot sensitive to mechanicalstimulation
PLLsensitive to stimulation similar to that of theannulus fibrosus
? Injury to other ligaments cause pain due to stresson other pain sensitive structures that arises fromligament laxity
(Hanley et al, 1999;)
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Lumbar Spine Muscles
Trunk muscles have been categorizedinto localand globalmuscle systems
Localrefers to deep muscles of thetrunk (eg. Multifidus, QL, transversusabdominis, interspinales)
Global refers to larger, more superficialmuscles (eg. Other abdominal muscles,longissimus)
(Bergmark, 1989)
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Muscles (contd)
Muscles can be acutely injured or bedue to overuse injuries
A typical inflammatory response takesplace when a muscle is injured
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Instability
Defined as an abnormal response to applied loads,
characterized by motion in the motor segmentbeyond normal constraints or motion quality
abnormalities
Basic concept is that abnormally large intervertebralmotions cause either compression and/or stretchingof the neural elements or abnormal deformations of
ligaments, joint capsules, annular fibres and end-plates, which all have a significant density ofnocioceptors
(Panjabi,1992)
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Sacroiliac Joint
Controversial source of low back pain
Constant debate regarding the amount
of movement, the location of the axesand the vulnerability of the joint todysfunction
Certain authors believe that instability ofthe pelvic girdle can lead to low backpain
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Sacroiliac Joint (contd)
Instability again refers to a loss of thefunctional integrity of a system that providesstability
In pelvic girdle, 2 systems that contribute tostability, the osteoarticularligamentousandmyofascial
These 2 systems have been referred to asform closure and force closure
Together they provide a self lockingmechanism
(Vleeming, 1990;1995)
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Spondylolysis /
SpondylolisthesisSpondylolysisrefers to a defect / fracture inthe pars interarticularis of arch
Spondylolisthesisrefers to a forwarddisplacement of one vertebrae over another(with or without a fracture)
Tissue of origin of pain is unknown
Places many back tissues under stressincluding discs, facets, ligaments
Fracture / defect itself could be source of pain(Swenson, 1998)
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Classification of LBP
Many authors have attempted toclassify LBP into categories to aid in
treatment and clinical decision making
4 classifications appear in the literature
that are widely used and thoroughlydescribed
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A Review of the Literature
of Classification Systems(Riddle, 1998) reviewed classification systemsdesigned for the majority of patients with low backpain
MEDLINE searchSystems reviewed were those most relevant tophysiotherapists
4 (of 11 found) were found to be most relevant and
reviewed criticallyMost appropriate because most thoroughlydescribed; used in continuing education courses andpractice;use diagnostic terms familiar to physios
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4 Approaches
1 developed by an orthopaedic surgeon
2 by physiotherapists
1 (Quebec Task Force Classification) bymany medical and non-medicaldisciplines
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Classification System of
Bernard & Kirkaldy-
Willis (1987)Developed by an orthopedic surgeon
Pathology based system
Purpose is to determine the pathologycausing the problem
23 categories in 3 groupsStrongly based on radiologic findings
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CategoriesGroup A
Herniated disc
Central Stenosis
Lateral StenosisSpondylolist-hesis
Segmental Instability
Group B
SI Joint Syndrome
Muscle Syndromes
Posterior JointSyndrome
Maigne Syndrome
Group C
Chronic Pain
Pseudo-arthrosis
Anky SponInfection
Tumour
Post fusion stenosis
ArachnoiditisFemoral nerveentrapment
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Classification System by
Delitto et al. (1995;1997)Developed by a physiotherapist
Clinical guideline index
Purpose is to guide treatment
Has 3 levels involving different types ofclinical decisions
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Classification Scheme
Physio ReferralConsultation
Stage II Stage IIIStage I
Extension
FlexionLateral Shift
Immobilization
Traction
Mobilization
Flexibilty
Deficit
StrengthDeficit
Cardio Deficit
Coord. Deficit
Body Mech.
Deficit
Activity
Intolerance
Work
Intolerance
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McKenzie Classification
Developed by a physiotherapist
Clinical guideline index
Purpose is to guide treatment
Has 13 categories
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Patients with low back pain who do not haveserious pathology, severe sciatica or
neurological deficits
PosturalSyndrome
4DysfunctionSyndromes
7DerangementSyndromes
Hip JointOr
SI JointProblem
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Quebec Task Force
Developed by experts in many fields
Judgement Approach
Purpose is to guide clinical decisionmaking, establish prognosis, for qualitycontrol and research
Designed for patients with low back painrelated to work injuries
1LBP without radiation of pain below gluteal folds,
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Work RelatedDisordersOf theSpine
1
2
34
5
6
7
8
9
10
11
LBP without radiation of pain below gluteal folds,No neurological signs
LBP with radiation not beyond the knee,No neurological signs
LBP with radiation below the knee,
No neurological signs
LBP with lower extremity radiation andNeurological signs
Presumptive compression of nerve roott based onRadiographic tests (eg.instability, fracture)
Compression of nerve root confirmed by imagingTests (eg. CT scan, MRI)
Spinal stenosis confirmed with radiologic tests
Post surgical status, 6 mos following surgery
Chronic pain syndrome, treatable active disease hasBeen ruled out
Other diagnoses (eg. Metateses, visceral disease)
A - < 7 daysB 7 days-7WeeksC - > 7 weeks
SymptomDuration
W WorkingI - Idle
WorkStatus
For Categories 1-4
For categories 1-4, 10, 11
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What System is Being
Used?No studies availablethat indicate clinicaluse / preference
2001 study didexaminephysiotherapistsreportedmanagement ofacute and subacuteLBP in Ontario
274 Ontario PTssurveyed whose weeklyworkload included more
than 10% of people withLBP
3 areasassessment,treatment, beliefsregarding treatment
3 scenarios andquestions related toassessment andtreatment
(Li & Bombardier, 2001)
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Results
Most respondentsassessed to rule outred flags
Assesment includedobservation,palpation, ROM,SLR, LE strength,reflexes, abdominalstrength, extensorstrength
>50% of the PTsreported would useother assessment
techniques such asMcKenzie, lumbar scan,SI testing, LE scan
No mention ofclassifying based on a
system (other thanMcKenzie)
Treatment was also notbased on a system
(LI & Bombardier, 2001)
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Risk Factors for Onset
of LBPAge 25-45
Male Sex
Physical Work Factors such as heavyphysical work (esp. lifting)
Psychosocial Work Factors such as lowworkplace social support and low job
satisfactionPrevious back pain
Low fitness level, obesity
Smoking(Hoogendoorn et al,2000;Bombardier et al,1994)
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Developmental
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Age Related Changes
As individuals age, their lumbar spinesundergo changes that are fairly uniformly
reflected by the populationThere is a natural biological process of agingin the lumbar spine
A natural process occurs but things we do
over the course of our lives can affect theprocess (eg. Exercise and osteoporosis)
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Discs
Becomes more fibrous,nucleus pulposusbecomes drier /
granularTherefore, less able toexert fluid pressure andtransmit weight directly
A greater share of thevertical load is borne bythe anulus fibrosus andis subject to greaterstresses
Previously thought thatdiscs loose their heightas we age, now know
height increases(10%for females and2%for males)
Loss of trunk stature is
due to decreases invertebral body heights
(Twomey & Taylor,1985;Bogduk & Twomey,1991)
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Vertebral Body
An overall decrease inbone density and bonestrength in vertebral
bodiesRelated to changes intrabeculae
A loss of horizontaltrabeculae removes the
bracing effect of thevertical trabeculae andthe load bearingcapacity of the centralportion of the vertebralbody weakens
Vertebrae then have torely more on corticalbone which fails sooner
than trabeculae boneThis reliance on corticalbone puts the vertebralbody at greater risk for
deformation and injury
(Bogduk & Twomey,1991)
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Facet Joints
Cartilage exhibits cell hypertrophy
Osteophytes often form
(Bogduk & Twomey, 1991)
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Clinical Implications
The older spine is less flexible and compliantand reacts more slowly to conditions ofsustained loading
Extensive research exists pointing to effect ofexercise on bone, education is our key rolewith regards to this
Smoking affects the integrity of the disc asdiscussed earlier, again our role as educatorsis emphasized
Education with regards to posture and body
mechanics
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Biomechanics
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Biomechanical Function
of the Spinal SystemTo allow movements between bodyparts
To carry loadsTo protect the spinal cord and nerveroots
(Panjabi,1992)
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A Biomechanical Theory
Proposed by Panjabi in 1992
Based on in vitro experiments of the
spineAttempts to explain the mechanics ofspinal motion
(Panjabi, 1992)
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Neutral Position
Neutral Positionthe posture of thespine in which the overall internal
stresses in the spinal column and themuscular effort to hold the posture areminimal
(Panjabi,1992)
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Neutral Zone
Neutral Zone (NZ)that part of thephysiologic range of motion, measured
from the neutral position, within whicheach spinal motion meets with minimalinternal resistance
(Panjabi,1992)
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Elastic Zone
Elastic Zone (EZ)that part of thephysiologic range, measured from the
end of the neutral zone up to thephysiologic limit within the EZ, spinal
motion is produced against a significant
internal resistance
(Panjabi,1992)
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Important Points
When spinal movement begins from neutral,spinal motion occurs first in the NZ, where itmeets with minimal stiffness
Movement is then through the EZ whichdisplays an increasing amount of resistanceto motion; the ligaments develop the greatestamount of tension
At this point these definitions only apply to theosseoligamentous spine (no muscles)
Therefore stiffness only refers to ligamentstiffness
(Panjabi,1992)
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Importance of Neutral
ZonePanjabis experiments revealed that changes
in the size or amplitude of the neutral zone
were more dramatic than were changes inoverall ROM as progressively greater loadswere applied to the spine
He noted that changes in neutral zone
provided a more sensitive indication of theonset of spinal injury
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Panjabis Experiments
Documented the load at which the NZ andROM increased & how they correlated withinjury
At a load of 6.3 kg dropped from 1 metre andaligned to produce compression/flexion, theNZ increased markedly while no significantchanges was seen in overall ROM
Thus when ligaments begin to fail, the NZ isthe first parameter to increase instability isseen in the NZ, not in overall ROM
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Effect of NZ
CompromisePanjabi noted injuries at the onset of NZinstability / laxity
Included: ligament tears, disc injuries,ligament avulsion tears, compressionfractures, torn facet joint capsules
(Panjabi,1992)
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Types of NZ
NZ is described as being of 2 typesactiveandpassive
Passivecan only be observed in experiments where
muscles have been removedActiveis seen in living or in vivo spine
The size of the NZ is likely to be of smaller amplitudeas the spinal muscles provide greater stiffnessthrough this portion of the ROM
Thus depending on the extent to which a personsmusculature is working optimally, their spine mayexhibit more or less movement in the NZ
(Panjabi,1992)
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Neutral Zone Summary
Overall spinal ROM is composed of motionthrough the NZ and EZ
NZ is a region of low stiffness or laxity
EZ is a region of high stiffness, whichincreases in a non-lonear fashion
Increases in the amplitude or size of the NZ
correlate with the onset of osseoligamentousinjury in the in vitro spine
The in vivo spine displays greater controlover size of NZ through the stabilizing effect
of muscles
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Biomechanical Study
In vivo experiment by McGill (1998)
Trained powerlifters
Video fluoroscopy, EMG (surface &indwelling)
Recording muscle action while subjects
lifted heavy loads
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Stabilizing Systems of
the Spine
ControlSubsystem
Neural
PassiveSubsystem
SpinalColumn
Active
Subsystem
SpinalMuscles
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Passive System
Ligaments do not provide stability to the spine interms of motion within the NZ; in this range theyfunction as proprioceptors
Ligaments likely provide stability only as movementapproaches limit of the EZ
Dysfunction of the passive system which could affectbiomechanics include overstretching of the ligaments,annulus tears or fissures, endplate microfractures,
disc extrusion into vertebral bodiesAll these factors decrease the load bearing andstabilizing capacity of the passive system
(Panjabi,1992)
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Active System
Muscles and tendons serve 2 functionswithin this model:
To provide stiffness or control of spinalmotion through the NZ
Proprioceptive feedback via GTOs andmuscle spindles
(Panjabi,1992)
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Neural System
The CNS is provided with input from a variety ofproprioceptors (GTOs, muscle spindles, jointmechanoreceptors)
With this input the neural control subsytem
determines specific reqirements for spinal stability,and causes the active system to achieve the stabilitygoal
The neural system monitors ligament stretch andmuscle tension to assess the position and load ofindividual spinal motion segments and the column ingeneral; with this feedback, the control subsystemcan alter the muscle forces acting across a spinal
joint to affect an appropriate stability response(Panjabi,1992)
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Motor Control
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Motor Control Issues
Has been a growing amount of research inthis area in the last decade
Studies have identified a number of motorcontrol issues which affect the overall stabilityof the lumbar spine
Research is now starting to reveal how thecentral nervous system prepares andmodulates the muscle system to support thelumbar spine and its segments for functionalactivity and load
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Transversus Abdominis
The deepest of the abdominal muscles
A cylinder like muscle with attachments to the
lumbar vertebrae via the thoracolumbarfascia
When it contracts bilaterally it produces adrawing in of the abdominal wall, resulting in
an increased pressure within the abdominalcavity and an increase in tension in thethoracolumbar fascia (Richardson et al, 1999)
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Main Deficits
3 main motor control problems identified in theTransversus Abdominis
These muscles appear to lose their normal
anticipatory function in patents with low back pain,exhibiting delays in activation & thus a loss of normalpreprogrammed function for support
In contrast to patients without low back pain, themuscle appears to be unable to function
independently of the other abdominal muscles inpatients with low back pain
Demonstrates phasic activity rather than the tonicactivity required for its supporting role
A Motor Control
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A Motor Control
Evaluation of
Transversus AbdominisStudy
Hodges etal, 1996
Subjects
N = 30
15 patientswith LBP
15 controls
Protocol
Subjectsperformedrapidshouldermovementsin responseto visual
stimulusMuscleactivity wasmeasured
Measures
Surface andindwellingEMG
Outcome
Trunkmuscles incontrolscontractedbefore orshortly afterdeltoid
T.A.delayed inLBP with allmovements
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Multifidus
Most medial of the lumbar muscles
Unique arrangement of predominantly
vertebra-to-vertebra attachmentsPredominantly Type I fibres (tonic role)
Contributes to the support and control of
the orientation of the lumbar spine andthe support of the lumbar segments
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Main Deficits
Appears to react by inhibition at asegmental level in acute episodes of
low back painSlower activation/recruitment renderingthe muscles too slow to meet the
demands of joint protection
(Hodges,2000)
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Exercise
Physiology
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Inactivity Changes
Low back pain leads to a variety ofdegenerative changes associated withinactivity
This is further compounded if there is anextended time span between injury andadmittance to rehab programs
Changes can include muscular atrophy,decreased flexiblityandcardiovasculardeconditioning
(Robert et al,1995)
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Muscle AtrophyDysfunction of the lumbar muscles in LBP patientshas been demonstrated using imaging modalities thatallow assessment of muscle size or cross sectionalarea and muscle consistency
Atrophy in terms of decreased size of the paraspinalmuscles has been demonstrated using imagingtechniques
Decreased muscle density, which can be a sign ofmuscle atrophy, is caused by fatty infiltration or actual
fatty replacement of fibresFatty degeneration of the multifidus and erectorspinae has been found in chronic LBP patients andpost operative patients
(Alaranta et al,1993;Richardson et al,1999)
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In addition changes in the internal structure ofthe type I fibres of the multifidus have beendemonstrated in LBP patients
The fibres have been described as moth
eaten in appearance
Changes in the internal structure of type Ifibres occur quickly (in biopsy specimens of
subjects with a symptom duration of only 3weeks)
(Richardson et al,1999)
Effects of Exercise on CSA
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of Multifidus in LBP
PatientsStudyHides et al,1996
Subjects
41 patientswith acuteLBP (< 3
weeks)
1st episodeof LBP
Protocol
2 groups
10 weeks ofRx
1.MedicalRx
2.MedicalRx + Ex
Measures
VAS, RMQ,US,Habitual
activity levelquestionnairre
Reax
weekly x 4wks + @ 10weeks
Outcome
Multifidusrecoverynot
spontaneous onremission ofsymptomsin group 1
Mmrecoveryrapid &morecomplete in
group 2
Effects of Work Hardening on
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g
Cardio Fitness & Muscle
StrengthStudy
Robert etal,1995
Subjects
31 LBPpatients
Acute &chronic
Protocol
Singlegroup
6 weeks of
cardio,wt.training,
Stretching& work sims
Measures
Sub maxcycleerg,Arcon
staticstrengthtestingdevice
Pre test and
post test
Outcomes
Markedimprovement in cardio
& muscularfitness
Nodifference
bt fitnesslevels forthose whoreturned towork & whodidnt
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Motor Learning
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Motor Learning
A set of internal processes associatedwith practice or experience leading to a
relatively permanent change in motorskill
(Schmidt & Lee,1999)
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Motor Learning & LBP
Very few, if any studies that look directly atmotor learning principles
Are studies that investigate body mechanicstraining and performance as well as studiesthat look at practice and ability to performcertain exercises
In addition there are studies that investigatefunctional training vs. non functional physioand how this affects RTW and functionalrestoration
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Motor Learning &
StabilityStage 1 The Cognitive Stage
Stage 2 The Associative Stage
Stage 3 The Autonomous Stage
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Stage 1- Cognitive Stage
A high level of awareness is demanded of subjects inorder to isolate the co-contraction of specific muscles
Aim of first stage is to train the specific isometric co-
contraction of transversus abdominis and multifidusat low levels of maximal voluntary co-contraction
Also to cease contraction of other muscle subsitution
Training is suggested 1x/day(10-15 mins)
Incorporate into functional tasks once achieved
At this stage a degree of pain control is expected withpostures = a biofeedback for client
(OSullivan,2000)
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Stage 2Associative Stage
Focus is on refining a particular movementpattern
Aim is to identify 2 or 3 faulty or painprovocative movement patterns and break
them down into component movements withhigh reps
Patient does this while maintaning co-contraction of local muscles
Can be performed for sit to stand, lifting, etcPatients do on a daily basis and increasespeed and complexity
(OSullivan,2000)
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Stage 3-Autonomous Stage
A low degree of attention is required for thecorrect performance of the motor task
The third stage is the aim of the exerciseintervention, whereby patients candynamically stabilize their spinesappropriately in an automatic manner during
the functional demands of daily living
(OSullivan,2000)
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Effects of Practice on
Stabilization ExsStudy
Hagins etal, 1999
Subjects
44asymptomaticvolunteers
(No LBPwithin 3mos ofstudy)
Protocol
2 groups
1.Ex
2.No Ex
Pretest of 7exercisesfor muscle
controlmeasured,pass/fail
Measures
Pretest of 7exs formusclecontrol witha pressuretransducer
Pass/fail
Measuredagain @ 4weeks
Outcome
Level of exattainmentincreasedfor ex groupwithinstructions& testing
F ti l R t ti
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Functional Restoration
vs. Regular PhysioStudies in the USA on the efficacy of FRare very positive regarding RTW rate
Studies in Canada and Finland do notdemonstrate as strong results
Hypothesized difference could be due tolower economic benefits during sick
leave in USA lead to favourable resultsfrom FR programs
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Review of LiteratureOverall the programs are effective in returning agreater percentage of individuals to the workplaceand in a more efficient manner (between 21-52%improvement in the rate of RTW vs control groups)
A review of the literature reveals the programs areeffective for chronic and acute LBP
1 study examining reinjury reported that 48% of Rxgroup and 79% of control group had a reoccurencewithin 1 year
Only 1 cost analysis study. The program resulted inan increase cost of $400/subject but there was asaving of $2000/subject in WCB costs, resulting insavings of $1600
(Lechner,1994;Bendix,2000)
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Motor Learning Summary
Few studies exist in the LBP literature directlyrelated to motor learning
Studies / information is available thatdiscusses different treatment methods thatinclude aspects of practice
Points to a need to research in motor learning
in this area and to investigate what motorlearning principles are being used in clinicalpractice
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Psychosocial
P h i l F t &
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Psychosocial Factors &
LBPPsychosocial factors play a crucial rolein low back pain clients
They play a particular important role inthe transition from an acute injury to achronic injury
Seems to be personal and work
psychosocial factors that affect LBPclients
P h i l F t @
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Psychosocial Factors @
WorkOne,psychosocial work characteristics candirectly influence the biomechanical loadthrough changes in posture and movement
Two,these factors may trigger physiologicalmechanisms, such as increased muscletension or increased hormonal excretion, that
may lead to organic changes or influencepain perception
(Hoogendoorn,2000)
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Three,psychosocial factors may changethe ability of an individual to cope with
an illness which could in turn influencethe reporting of symptoms
Four, the association may be
confounded by the effect of the physicalfactors at work
(Hoogendoorn,2000)
P h i l F t t
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Psychosocial Factors at
WorkA 2000 review of the literature found 6reported psychosocial factors at work thatinfluence LBP
Work Pace
Qualitative Demands
Job Content
Job Control Social Support in the Workplace
Job Satisfaction(Hoogendoorn,2000)
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Work Pace
3 high quality studies1 found no significant effect
1 found a statistically significant effect of ahigh work pace on back related shortabsenteeism
1 found a statistically significant effect of ahigh work pace on sciatic pain
When rated the studies showed there isinsufficient evidence of an effect of high workpace on the risk of pain, due to inconsistentfindings
(Hoogendoorn,2000)
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Qualitative Demands
Include conflicting demands, interruption oftasks, and intense concentration for longperiods
1 high and 1 low quality study
1 study found that high conflicting demandshad a statistically significant effect on shortand long absences from work due to pain
When rated there is insufficient evidence ofan effect of high qualitative demands on therisk of LBP
(Hoogendoorn,2000)
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Job Content
Includes monotonous work and workwith few possibilities to learn new skills
4 high quality studiesNo statistically significant effect wasfound
(Hoogendoorn,2000)
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Job Control
Includes aspects such as autonomy andinfluence
2 high quality studiesBoth found no significant effect
(Hoogendoorn,2000)
Social Support in
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Social Support in
WorkplaceIncludes social support of coworkers andsupervisors, relationships at work andproblems with coworkers and supervisors
5 high quality studies4 of 5 showed that low support had astatistically significant effect
Rating system showed that there is strongevidence for low social support in theworkplace as a risk factor for back pain
(Hoogendoorn,2000)
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Job Satisfaction
7 high and 2 low quality studies
Researchers in 5 high quality studies
found that low job satisfaction had astatistically significant effect
Strong evidence for low job satisfaction
as a risk factor for low back pain
(Hoogendoorn,2000)
Personal Psychosocial
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Personal Psychosocial
FactorsThe same review in 2000 examined the studiesavailable on the effect of psychosocial factors inprivate life and there effect on LBP
Only 1 high and 2 low quality studies were foundFactors studied included family support, presence ofa close friend, social contact, social participation andemotional support
In general, no significant effect was found
Application of the rating system found there isinsufficient evidence of an effect of psychosocialfactors in private life
(Hoogendoorn,2000)
P h l i l F t i th
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Psychological Factors in the
Development of Chronic LBP
Psychological factors in addition to being riskfactors for LBP also appear to play a role inthe development of chronicity in LBP
A systematic review of the literature done byPincus et al (2002) reviewed studies thatinvestigated psychological factors as
predictors of chronicity/disability inprospective cohorts of LBP
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Method
6 studies met inclusion criteria
Inclusion criteria :prospective cohortsconcerning LBP;subjects with acute or
subchronic LBP;measurement of at least 1psychological variable at baseline
Rated on 3 main criteria (methodologicquality, quality of measurement of
psychological factors and quality ofmeasurement of psychological factors)
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Results
4 psychosocial factors are identified inthe literature
Psychological distress/Depressive Mood Somatization
Personality
Cognitive Factors
(Pincus,2002)
P h l i l Di t /
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Psychological Distress /
Depressive Mood
Due to tools used in studies difficult todifferentiate between psychological distress,depressive symptoms & depressive moods
Authors therefore used distress to representa composite of all terms
Distress is a significant predictor ofunfavorable outcome
This effect was independent of clinicalfactors, such as pain and function @ baseline
(Pincus et al,2002)
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Somatization
I high quality study and 1 acceptablestudy
Somatization scales predict unfavorableoutcomes
(Pincus et al, 2002)
P lit d C iti
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Personality and Cognitive
Factors
Personality Minnesota
Multiphasic
Personality Inventory(MMPI) subscale ofhysteria wasreported to be apredictor of RTW in 1
study Overall quality rated
low
Cognitive Factors Dealt with coping
strategies, fearavoidance,catastrophizing
Studies had a low qualityrating
(Pincus et al,2002)
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Summary
Distress and somatization are confirmed as having arole in the progression to chronicity in LBP
2 areas of psychological risk are surprisinglyunderrepresented: fear avoidance and
catastrophizingAuthors commented that although it is felt that painrelated fear and avoidance appear to be an essentialfeature of the development of chronicity, support fromprospective studies is sparse
Research regarding catastrophizing predictingdisability is based on cross sectional studies or basedon groups with different disorders
(Pincus et al,2002)
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Functional Self Efficacy
Refers to confidence judgments regarding theability to execute or achieve tasks of physicalperformance
Suggests that those having higher levels ofFSE and believing they could performfunctional tasks could be expected to reachhigher levels of physical performancebecause they invest more effort and
persistence and, consequently are less likelyto become preoccupied with expectations offurther pain and injury
(Lackner et al,1996)
FSE & Chronic LBP
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FSE & Chronic LBP
StudySome interesting conclusions made bythe authors
A link between FSE and disability FSE has a predictive power
Individuals with high FSE may be lessprone to thoughts of future harm and mayapply coping skills more effectively
(Lackner et al,1996)
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An Overview of
Treatment Approaches
used in LBP
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Interventions
A wide range of interventions exist forthe treatment of LBP
These include Exercise
Modalities
Manual Therapy
Education Functional Restoration Programs
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Efficacy
With the exception of exercise andfunctional restoration no evidence exists
that substantiates effectiveness of theother interventions in a low backpopulation
Lack of evidence is mostly due to (a)lack of studies and (b) lack of high levelstudies
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Exercise
Literature seems to be divided into 2groups
General Exercise (stretching,strengthening, aerobic, McKenzie)
Stabilization Exercise (specific to deeptrunk muscles)
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General Exercise
A review was published in 2001 undertaken by thePhiladelphia Panel
The review evaluated 9 rehab interventions for LBP1 being exercise
Studies were eligible if they were RCTs,nonrandomized controlled clinical trials (CCTs), casecontrol and cohort studies
Studies had to evaluate exercise in nonspecific LBP
and included post surgerySummarized exercise studies according to acuteLBP, subacute LBP and chronic LBP
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Exercise & Acute LBP
Acute defined as < 4 weeks
4 RCTs
Exercises included McKenzie, back extension,
strengthening exsNo efficacy was demonstrated
Therapeutic exercises were no better than control forimproving function, ability to work and pain
Clinical Recommendations: poor evidence to includeor exclude stretching or strengthening exs alone asan intervention for acute LBP
Exercise & SubAcute
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Exercise & SubAcute
LBPSub acute defined as 4-12 weeks3 RCTs included
Exercises included McKenzie, Flexion Exs,strengthening exsClinically important benefits found withregards to pain relief, patient assessed globalcondition & functional status
Recommendations: good evidence to includeflexion, extension and strengthening exs asinterventions for subacute LBP
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Exercise & Chronic LBP
Chronic defined as > 12 weeks
8 RCTs
Exercises included: flexion, extension,stretching, circuit training and strength exsClinically important benefit was demonstratedfor pain relief & functional status
Recommendations: good evidence to includestretching, strengthening and mobility exs asinterventions for chronic LBP
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Stabilization Exercises
A review was done by Gallagher (myself) in2002
Identified and reviewed literature available onexercise studies that incorporated the use ofstabilization exercises
Stabilization exercises was defined as
exercises that incorporated training of themultifidus and transversus abdominismuscles
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Summary of Literature
5 studies reviewed
3 RCTs and 2 single group designs
Included studies of acute and chronic clients
Clinically important benefits included painrelief, decreased disability and decreasedmuscle atrophy
Recommendations: Stabilization exs arerecommended for acute and chronic clients toaddress pain, disability, muscle atrophy andpossibly motor control issues
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An Integration of
Approaches in Clients
with LBP
Biomechanics: Clinical
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Biomechanics: Clinical
Implications
As therapists we should:
Be aware of the neutral zone and factors
that affect it Maintain neutral zone with stability exs
Protect the joint with proper exercises andeducation on posture and ergonomics
Help maintain muscle strength
Motor Control: Clinical
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Motor Control: Clinical
Implications
As therapists we should:
Be aware of muscles most affected in LBP
Provide exercises relevant to theseaffected muscles
Measure outcomes as closely as possible
Attempt to have patients minimize use ofinappropriate muscles
Motor Learning: Clinical
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Motor Learning: Clinical
Implications
As therapists we should:
Provide practice and feedback for clients
Encourage practice outside of treatmentsessions
If work related injuries, provide tasks /treatment that is specific to tasks they have
to return to
Exercise Physiology:
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Exercise Physiology:
Clinical Implications
As therapists we should:
Be aware of effects of inactivity in the LBP
client Enhance cardiovascular fitness of LBP
clients
Address muscle atrophy with specific
exercise training
Psychosocial: Clinical
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Psychosocial: Clinical
Implications
As therapists we should:
Be aware of the factors that affect LBP and
chronicity of LBP Identify factors that may be affecting a
clients treatment / return to work
Identify If work psychosocial factors are
affecting treatment
Attempt to increase functional self efficacy
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An Integrated Model to
Address Function in
Low Back Pain Clients
Group Activity
Obj ti
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Objectives
To identify the underlying causes andmechanisms of mechanical low back pain
To understand some of the physical,biomechanical and psychosocial impairments
/ approaches associated with mechanical lowback pain
To integrate the approaches into a clinicalmodel and incorporate treatment strategiesinto the approach