Transcript Back Pain & Treatment modalities

Back Pain & Treatment
Modalities
Dr. Dawood Nasir
Director Acute Pain & Regional Anesthesia
UTSouthwestern Medical Center
Overview
• Back pain affects most people at least once
over their lifetime.
• It can be a cause for lost wages & productivity
• Most people will become better in 6 weeks
Anatomy
• The back is composed of
vertebrae, muscles,
ligaments, intervertebral
disc,& nerves.
• There are 7 cervical, 12
thoracic, 5 lumbar & 5
coccygeal vertebrae
• Spinal cord has cervical
lordosis, Thoracic kyphosis,
& lumbar lordosis
Assessment of Low Back Pain
• History & Physical: Nocturnal exacerbation
occurs w tumors or inf, w benign causes like
herniated disc pain improves w bed rest
• Limitation of spinal motion correlates with the
presence of lower back disability
• Palpation: Gentle & systemic palpation of the
back, coccyx, sacrum, levator ani, coccygeus,
& piriformis ms, & associated ligament done
• Muscle spasm: has localized tenderness, &
increase in ms tone
Assessment of Back Pain
• Pain on percussion occurs with metastases or
inf, does not occur w disc protrusion & spasm
• Radiological test: Plain Xrays show
degenrative disc ds, spondylitis, compression
fx, metabolic bone disorder, bone tumors,
congenital anomalies & transitional vertebrae
• Oblique view of lumbosacral level is used to
visualize facet & sacroiliac joint
• Flexion-extension view is added when ever
spinal instability suspected
Straight leg raising test
• Straight leg raising test
should be performed to
detect nerve root irritation
• Even with a soft tissue pain
source, SLR can be used
as an index of improvement
• A +ve crossed SLR test has
the highest correlation w
myelographic finding of a
herniated disc
Causes of back pain
• Pain sensitive structures are the supporting
bone, articulations, meninges, nerves,
muscles, & aponeuroses
• Vertebral body despite being short is actually
a long bone with end plates of hard bone & a
center of cancellous bone
• It is innervated by dorsal roots
• Periosteum is pain sensitive as is facet joint
which have a capsule & meniscus richly
innervated w nociceptors
Muscular Pain
• Most back pains are
caused by sprain or
strain of the back
muscles & ligaments
• Pain will be in discrete
area & tender to touch
• It is of aching quality &
may involve muscle
spasm
• Pain not involved
shooting pain
Spinal causes
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Osteoporosis
Osteomylitis
Herniated Disc
Spondylolisthesis
Spondylolysis
Facet hypertrophy
Ischemia of the spinal
cord
Osteoporosis
• Osteoporosis is painful due
to microfracture
• Absence of wt bearing due
to bed ridden leads to
demineralization & fx upon
wt bearing
• Postmenopause & pt Rx
with corticosteroid is at risk
• Other cond r/o w serum
protein electrophoresis, sed
rate, alkaline phosphatase,
ca, x-rays.Rx
Biphosphonate, raloxifene
Osteomyelitis
• Vertebral osteomyelitis
presents as subacute back
pain that increases over
days to weeks
• Pain in low back if unRx
focal weakness, bowel &
bladder problem results
• Most common in lumbar
spine in men over 50
• With AIDS younger men &
cervical spine affected
Osteomyelitis
• In immunocompetent hosts, Staphylococcus
aureus inf most common
• Inf involves vertebral bodies, endplates, & disc
spaces, spares post elements
• In rare cases actinomycosis or
coccidiodomycosis, posterior elements
involved & spine becomes unstable
Vertebral metastases
• Vertebral metastasis presents as localized,
deep, aching, back pain
• If nerves are involved, pain occurs in neural
distribution
• Thoracic spine is most commonly affected
• Epidural spinal cord compression is a medical
emergency & pt may present with paraparesis,
sensory loss, bowl & bladder involvement
Vertebral metastases
• On plain film earliest sign of
spinal metastasis is erosion of
pedicle
• Over time vertebral body
begins to lose height
• MRI reveals change in signal
intensity in vertebral body
• As tumor progresses, it may
be seen invading epidural
space & compressing spinal
cord
Facet joint pain
• The vertebral bodies have
4 facet joint, 1 pair above
& 1pair below
• Synovial joints mean they
have fluid with in them
• Back pain caused by
arthritis of the facet joints
is mostly midline & may
spread to the back & to
the flanks
• Gets worse with bending
backward & side to side
Herniated Disc
• Intervertebral disc consists of an outer fibrous
body called the annulus fibrosus & an inner gel
like substance called the nucleus pulposus
• It acts as a shock absorber & spacer for the
spine giving room for the intervertebral neural
foramina which are portals for the exit of the
spinal nerves
• The nucleus pulposus contains noxious
chemicals which can be irritating to nerves
Herniated disc-cont• The intervertebral discs lie between the
vertebral bodies. In front is the ant. longitudinal
ligament & behind the post. longitudinal
ligament & behind that is spinal cord.
• Wear & tear can cause annulus fibrosus to
weaken allowing bulges of nucleous pulposis
• These bulges may protrude out enough to
touch the spinal cord causing irritation to nerves
• These large disc bulges are called herniation
Herniated Disc
• With extreme forces these disc
bulges may tear the annulus
fibrosus & allow leakage of
nucleus pulposus
• This is observed as sudden sharp
pain radiating down the leg
• The chemicals of nucleus
pulposus can cause swelling of
nerves resulting in constant
burning pain termed lumbar
radiculopathy or sciatica, pain
radiating down the leg & feet
Types of Herniate Disc
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Disc degeneration
Disc prolapse
Disc extrusion
Disc seqestration
Radiographic herniated disc
Spondylosis
• It can be described as
arthritis of the spine
• The bony surfaces may
become roughened & bony
spurs may develop & intrude
upon the spinal canal
Spondylolisthesis
• It is a slippage of the
vertebra upon one
another
• The vertebra are
usually aligned so that
each one is stacked like
“legos” so that the
spinal canal is a fairly
straight tube
Spondylolithesis
• If there is a slippage,
the spinal canal has a
kink & is a smaller in
that area
• When spinal stenosis
occurs, it squeezes
upon the spinal cord
• This may cause
irritation or ischemia of
the spinal cord & lead
to cramping or aching
of the legs
Grades of Spondylolisthesis
Piriformis Syndrome
• It is a syndrome of low
back & leg pain due to ch.
Contracture of the
piriformis muscle that
causes irritation of sciatic n
• Gluteal pain radiates to
sciatic nerve
• It occurs by compression of
nerve between ms. Or ms
& pelvis
Buttock pain
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Common causes are
Piriformis syndrome
Ischial tuberosity inj.
Rupture of gluteal ms.
Piriformis Syndrome
• It is also called “hip pocket
neuropathy” or “wallet neuritis”
• Piriformis ms is flat, pyramidal ms
that originates from ant surface of
sacrum from S2-S4 & sacrotuberous
lig passes through the upper part of
greater sciatic notch, & inserts on
superior surface of great trochanter
Treatment of Back Pain
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Walking is best exercise
Physical therapy for core stabilization
Spinal manipulation & manual therapy
Analgesics like acetaminophen, NSAID’S,
antidepressants
• Application of heat or ice
• Acupuncture
• Corticosteroid injections
Treatment of Chronic Back Pain
• Treat the cause like in osteomylitis, surgery
with antibiotics is used
• Vertebral metastasis will respond to high
doses of dexamethasone, definitive treatment
with radiation & surgery
• Osteoporosis treated with Biphosphonate,
Robaxifene
• Muscle spasms may respond to ms relaxants
Back Exercises
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Ankle pump
Heel slides
Abdominal contraction
Wall squats
Heel raises
Straight leg raises
Knee to chest stretch
Hamstring stretch
Exercises with swiss ball
Epidural steroid injection
• Epidural space
identified w loss of
resistance tech or
fluroscopy
• 60-80 mg of triamcilone
with 0.25% bupivacaine
injected
Intradiscal electrothermic therapy
• IDET is done using fluoroscopy,
a hollow needle containing
flexible tube & heating element
is inserted into spinal disc
• The catheter placed in a circle
in the annular layer of disc &
slowly heated to 194 deg.
• The heat is meant to destroy the
nerve fibers & toughen the disc
tissue, sealing any small tear
Vertebroplasty
• Under fluoroscopy, a
hollow needle is inserted
& a cement is injected to
restore the vertebra
Kyphoplasty
• In kyphoplasty a ballon
is inserted through the
hollow needle into the
fractured bone to restore
the height & shape of the
vertebra.
• Once the ballon is
removed, the cement
mixture is injected.
Kyphoplasty / Vertebroplasty
Spondylolithesis
Discectomy
• A scope is inserted
through a small cannula
to inspect disc surface
• Peri-annular fat is
removed & small
capillaries are
cauterized
• Small nerves in the
annular fat can be
removed with periannular tissue
WHO Pain ladder
GOAL:
Freedom From Pain
STEP 3
Pain Persists
STEP 2
Pain Persists
STEP 1
• Step 3: Opioids for
moderate-to-severe
pain +/- non-opioid +/adjuvant therapy
• Step 2: Opioids for
mild- to-moderate
pain +/- non-opioid +/adjuvant therapy
• Step 1: Non-opioid
+/- adjuvant therapy
WHO Pain Ladder
• Step 1 Mild (pain rating 1-3)
Non opioid + co-analgesics
e.g. NSAID+TCA/membrane stabilizer/ms.relax.
• Step 2 Moderate (pain rating 4-6)
Opioid + Non opioid + co-analgesics
Lorcet + NSAID+TCA/memb. Stab./ms. Relax.
• Step 3 Severe ( pain rating 7-10)
Pure opioids + non-opioids + co-analgesics
e.g. Morphine SR + NSAID + above.
Opioid combination products
Drug
Opioid
Non-opioid
Doses
Lortab (vicodin)
Hydrocodone
5 mg
APAP 500 mg
1-2 q 4 hrs.
Max. 8 tabs/day
Lorcet
Hydrocodone
10 mg
APAP 650 mg
1 q 4 hrs.
Max. 6 tabs/day
Tylenol # 3
Codeine 30 mg
APAP 300 mg
1-2 q 4 hrs.
Max. 13 tabs/day
Norco
Hydrocodone 10
mg
APAP 325 mg
1-2 q 4 hrs.
Max. 12 tabs/day
Percocet
Oxycodone 5 mg
APAP 325 mg
1-2 q 4 hrs.
Max. 12 tabs/day
Tylox 5/500
Oxycodone 5 mg
APAP 500 mg
1-2 q 4-6 hrs.
Max. 8 tabs/day
Acetaminophen (Tylenol)
• MoA: Cox-3 inhibter of PG in the CNS &
peripheral pain impulse
• Pain indication: Use alone for mild pain
• Do not exceed 4 gms / day
• Lorcet – 6 tabs/day= 60 mgs morphine
• Lortab- 8 tabs / day=40 mgs morphine
• Adverse effects:
-Lightheadedness, dizziness, hepatotoxicity
with high doses & chronic use
NSAID’S
• Indications: anti-inflammatory, antipyretic, analgesic
• Acetylsalicylic acid ( ASA ) irreversibly inhibits platelet
• Side effects: Reversible antiplatelet effect, minimal
w/ non-acetylated salicylates ( eg Disalcid, Dolobid )
- GI ulceration, less w ibuprofen, etodolac, salsalate,
nabumentone
- Nephrotoxity – caution in CHF, dehydratation, elderly
- Hepatotoxicity: caution in elderly & alcoholics
- Avoid in asthmatics & nasal polyps
Mechanism of Action
– Phospholipids, released from cell membrane are cenverted
to Arachidonic acid by phospholipase A2
– Arachidonic acid is acted by lipo-oxygenase to be converted
to Leukotrienes
– Cyclo-oxygenase acts on Arachidonic acid to form
Prostaglandin endoperoxides which are converted to
Prostaglandin G & by isomerase into Prostaglandin E2,
Prostaglandin D2, & F2 alpha
– Prostaglandin H is formed from prostaglandin endoperoxides
& converted by Thromboxane to Thromboxane A2 &
Thromboxane B2.
– Prostacyclin synthetase converts prostaglandin
endoperoxides to Prostacyclin ( PGI )
Co-analgesic Pain Medications
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Antiepileptics
Antidepressants
Muscle Relaxants
Anesthetics
Corticosteroids
Psychostimulants
Substance P
inhibitors
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Alpha-2 agonists
Neuroleptics
Antiarryhmics
Benzodiazepines
Antiepileptics
• MOA: Block Na+ & Ca+ channels>>inhibits release of
glutamate>> stabilizes neural memb.
• Uses: Trigeminal neuralgia, peripheral neuropathies,
herpetic neuralgia, phantom limb pain, migraines.
• Aniepileptics: Gabapentin, Carbamazepines,
topiramate, phenytoin, oxycarbamazepine, pregabalin
• Comared to TCA’s:
-equally efficacious in painful DN
-some AED may be more expensive
- differences in safty profile
- synergy with AED plus TCA
Gabapentin (Neurontin)
• MOA: a 2-delta ca+ channel subunit modulator
• Uses: Peripheral neuropathic pain, phantom limb pain,
CRPS, post herptic & trigeminal neuralgia.
• Doses: adjust for elderly & renal failure
-range 300- 3600 mg /day divided in 3-4 doses
• Somnolance, dizziness, constipation, fatigue,
peripheral edema, difficulty concentrating
Pregabalin (Lyrica)
• MoA: a 2 delta Ca+ channel subunit modulator
• Pain uses: Diabetic & post herpetic neuropathic pain
at doses 300-600 mgs/day divided 2-3 X.
• Other neuropathic pain conditions, fibromyalgia,
generalized anxiety disorder.
• Compared to gabapentin:
- Bioavailability remains 90% at all doses
- Time to effective dose (150-300mg/day) is 1-3days
- Class v schedules drug.
Carbamazepine ( Tegretol)
• MoA: Na+ & Ca+ channel blockade
• Pain uses: trigeminal neuralgia,
glossopharyngeal neuralgia, DPN
• Dosing: 200-1000mg divided 2-3X (with food)
• Side effects: N & V, dizziness, sedation,
transient leukopenia, hepatic toxicity,
thrombocytopenia, diplopia, hyponatremia,
rash, Steven-Johnsons syndrome.
Tricyclic antidepressants
• MoA: inhibits re-uptake of NE, SE, antihistamine
• Pain indications: Painful neuropathies, Phantom
limb pain, migraine prevention
• Dose: start low & adjust every 2- 3 days
• Drug interactions
- caution with other anticholinergics/serotonergics
- CYP2D6 substrate ( all TCA’s)
- CYP3A4 substrate ( Elavil )
Choice of A TCA
• Amitriptyline ( Elavil)
- most widely studied
- more side effects- hang over effect.
• Doxepin ( Sinequan )
- similar to Elavil, but shorter duration of sedation
• Desipramine ( Norpramin ), Nortriptyline ( Pamelor)
- may cause insomnia
- less anticholinergic effect
- Desipramine may cause orthostatic hypotension
TCA – Side Effects
Side effects
• Blurred vision
• Cognitine changes
• Constipation
• Dry mouth
• Orthostatic hypotention
• Sexual dysfunction
• Tachcardia
• Urinary retention
• Desipramine
• Nortriptyline
• Doxapin
• Amitriptyline
Duloxetine ( Cymbalta )
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MoA : Dual reuptake inhibitor ( NE & SE )
Indications : Neuropathic pain, depression
Dosage : 30 mgs PO qd to 60 mgs PO bid
Side effects : nausea, dry mouth, constipation
decreased appetite, dizziness, insomnia
• Drug interaction : CYPIA2 & 2D6 substrate –
SSRI’s , quinidine, cimetidine, quinolenes, may
increase duloxitine levels.
- mod. Inhibitor of CYP2D6 – increases TCA’s,
phenothiazine, type 1C antiarrythmias
Muscle Relaxants
• Heterogenous group of medications:
- Spasticity from upper motor neuron syndrome
- Muscular pain & / or spasm from peripheral
musculoskeletal condition.
- Dose : may dose 6-8 hrs ATC or give more hs if
daytime drowsiness does not resolve ( e.g.
Flexaril 10-30 mg po qhs )
Side effects:Drowsiness,dizziness,blurred vision
Drug interaction: Other CNS depressants
Muscle Relaxants
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Spasticity:
Baclofen ( Lioresal )
Tizanidine ( Zanaflex)
Dantrolene ( Dantrium )
Diazepam ( Valium )
• Muscular pain & spasm
- Methcarbamol (Robaxin)
- Cylobenzaprine(Flexaril)
- Carisoprodal ( Soma )
- Baclofen ( Lioresal )
- Tizanidine ( Zanaflex )
Muscle Relaxants
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Spasticity:
Baclofen ( Lioresal )
Tizanidine ( Zanaflex)
Dantrolene ( Dantrium )
Diazepam ( Valium )
• Muscular pain & spasm
- Methcarbamol (Robaxin)
- Cylobenzaprine(Flexaril)
- Carisoprodal ( Soma )
- Baclofen ( Lioresal )
- Tizanidine ( Zanaflex )
Baclofen ( Lioresal )
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Baclofen ( Lioresal ) – gaba – b agonist
Indications : Neuropathic pain, spasticity
Side effects : less sedating, ms weakness
With drawl syndrome: spasticity,
hallucination, anxiety,seizure when doses
80 mgs/ day or intrathecal baclofen are
stopped abruptly
Flexeril ( Cyclobenzaprine )
• Indications : muscle spasms, neuropathic
pain
• Side effects : CNS & anticholinergic effect
• Drug interactions : w/TCA’s additive
anticholinergic side effects, CYPIA2
substrate
Systemic / Topical anesth.
• Lidocaine 5% patch apply to intact skin at most
painful site, 1- 3 patches for 12 hrs
• Indications : Post-herpetic neuralgia, post
thoracotomy, mastectomy, pain syndrome.
• Side effects : site irritation, dizziness, arrythmia’s
• Lidocaine cream 5% apply to affected area 3-4 X /
day for short term use.
• Mexileteine 150 mg po bid adjust q 2-3 days upto
400 mgs / day
- Indications : resistant neuropathic pain
- Side effects : dizziness, tremor, GI upset,
arrythmia’s
Tramadol ( Ultram )
• MoA : mu – opioid receptors, NE & SE
reuptake inhibitors
• Mixed mild to moderate pain
• Side effects: dizziness, nausea, constipation,
somnolence, sweating, pruritus, sz,
serotonergic syndrome
• Maximum dose: 400 mg / day
• 10-20% pt. lack CYP2D6 needed to form MI
( metabolite ) impact or efficacy & safety
• Dose conversion: 50 mg = codeine 30 mg.
Botulinum Toxin A ( Botox )
• MoA : direct antinociceptive effects, prolonged
ms relaxation by inhibition of acetylcholine
release at the neuromuscular junction
• Indications : Blephrospasm, facial wrinkles, ms
spasm
• Duration of effect : 3 – 4 months
• Side effects:
Opioids
• MoA : agonist on mu, kappa, & delta receptors
• Methadone: also NMDA receptor antagonist &
NE/SE reuptake inhibitor
• Indications: Acute & ch Moderate to severe pain
• For most type of pain with limited use in
- Neuropathic pain
- Spinal cord compression
- Bone pain