Overview of Spasticity

Jaime M. Levine D.O.

March 2013

Overview

• A component of the UMN syndromes – Traumatic SCI and SC disorders

– Brain Injuries

– Neurodegenerative diseases, CP

• Presents with varying degrees of clinical

problems that challenge patients, families

and health care professionals.

Definition

• A motor disorder characterized by a

velocity-dependent increase in the tonic

stretch reflexes (muscle tone) with

exaggerated phasic stretch reflexes

(tendon jerks, clonus) resulting from

hyperexcitability of the stretch reflex.

Lance 1980

Definition

• Increased resistance to passive stretch

which is… – Velocity-dependent

– Direction-dependent

– May have initial free motion

• “clasp-knife” phenomenon

• Positive and negative symptoms

Spasticity

• Positive Symptoms

– Hyperreflexia

– Clonus

– Co-contractions

– Postural abnormalities

– Disorder of voluntary

movements

– Increased muscle

stiffness

• Negative Symptoms

– Muscle weakness

– Incoordination

– Fatigue

– Pain

Spasticity

(When you have a spastic pt, you see…)

1. Intrinisic tonic spasticity • Increased tone

• Increased denervation hypersensitivity and changed muscle properties

2. Intrinsic phasic spasticity • Hyperreflexia and clonus

3. Extrinsic spasticity • Involuntary spasms in response to a perceived stimulus.

Pathophysiology

• Not fully understood – Suspect loss of supraspinal inhibitory and excitatory inputs

causes:

• Increased excitability – Hyperexcitability of interneurons and alpha motor neurons leads to

exaggerated stretch reflexes

– Denervation hypersensitivity

• Reduced inhibition – Loss of descending inhibitory pathways to antagonist muscle leads

to co-contraction

• Plasticity?

Benefits of Spasticity

• Stability in sitting/standing

• Maintains muscle bulk

• Increases venous return

• Improves cough

• Improves functional capabilities – ADL’s

– Mobility

Problems with

Spasticity

• Impacts function and QoL – Medical

• Pain, stiffness, spasms, positioning, contractures, skin breakdown, infections and ulcers

– Physical

• Mobility, ADLs, hygiene

– Psychosocial

• Cosmesis, recreational, sleep, mood, self esteem, sexual

– Vocational

Assessment of Spasticity

• History and physical

• Scales

– Ashworth, Modified Ashworth, VAS, SCATS, Penn Spasm Frequency, Tardieu scales

• Tests

– Biomechanical

– Pendulum Wartenberg and joint oscillation tests

– Electrophysiologic (mostly used in research)

– H-reflex, H/M ratio, F-wave, Surface EMG

Clinical Scales

• Ashworth Scale: ordinal scale for measuring musle tone

• Modified Ashworth Scale: defines the lower end of the scale by

adding the 1+

• SCATS: spinal cord assessment tool for spasticity

• VAS: visual analogue scale (subjective)

• Penn Spasm Frequency Score: ordinal scale for measuring leg

spasm frequency per day

Clinical Scales, Continued

• Tardieu Scale – interval scale for measuring stretch response reactions at

specific velocities

– modified scale became much more involved and added specific

positions and alignments and measured angles

– R2 (muscle length at rest)

– R1 (muscle length when catch occurs)

– difference b/w the two is key

» large difference means large dynamic component

» small difference means more fixed and possibly

contracted

Testing Positions

Upper Limb

To be tested in a sitting position, elbow flexed by 90°

at the recommended joint positions and velocities.

Shoulder

Horizontal Adductors V3

Vertical Adductors V3

Internal Rotators V3

Elbow

Flexors V2 Shoulder adducted

Extensors V3 Shoulder abducted

Pronators V3 Shoulder adducted

Supinators V3 Shoulder adducted

Wrist

Flexors V3

Extensors V3

Fingers Angle PII of digit III- MCP

Palmar Interossei V3 Wrist resting position

+ FDS

Lower Limb

To be tested in supine position, at recommended joint

positions and velocities

Hip

Extensors V3 Knee extended

Adductors V3 Knee extended

External Rotators V3 Knee flexed by 90

Internal Rotators V3 Knee flexed by 90

Knee

Extensors V2 Hip flexed by 30

Flexors V3 Hip flexed

Ankle

Plantarflexors V3 Knee flexed by 30

Ref: Boyd R, Graham K. Objective Measurement of clinical findings in the use of Botox type A for the

management of children with Cerebral Palsy. European Journal of Neurology 6(Supp 4) S23-35

Tardieu G, Rondont O, Mensch J, Dalloz J, Monfraix C, Tabary J. Responses electromyograhpiques a

l’etirement musculaire chez l’homme normal. Revue Neurologie + 97(1), 60-61

Gracies J, Marosszzeky J, Renton R, Sandaman J, Gandevia S, Burke D. Short term effects of dynamic

splints on the upper limb in hemiplegic patients. Archives of Physical Medicine and Rehabilitation, 81

1547-1555.

Modified Ashworth Scale

Score Criteria

0 No increase in tone

1 Slight increase in tone (catch & release at end of ROM)

1+ Slight increase in tone, manifested by a catch, followed by

minimal resistance through remainder (<1/2) ROM

2 Marked increase in tone through most of ROM, but affected

part easily moved

3 Considerable increase in tone; passive movement difficult

4 Affected part(s) rigid in flexion or extension

Quantitative Tests: Difficulties

• Static test for dynamic process

• Spasticity changes based on time of day and with many

other factors

• Test position usually not the position of function

• Poor correlation between scales

• Discrepancy between self-rated and clinical scores

• Decrease in score does not necessarily correlate with

improved function (weakness, muscle coordination are also

factors)

• Does not fully evaluate specific impact of spasticity in

limiting activity or participation

Questions to Ask before

choosing Treatment

• Does the spasticity cause pain?

• Is it leading to contracture?

• Does it interfere with function or sleep?

• Does it interfere with passive care?

• Does it have psychosocial consequences?

• Is cosmesis an issue?

• Is it interfering with proper brace fitting?

• Does it affect QoL?

Treatment Concepts

• Goals must be reality based and meaningful

– Decrease pain

– Increase function (i.e. mobility, ADL, QoL)

– Prevent contractures

• Decisions

– Severity

– Scope: local vs. regional

– Medical and cognitive status of patient

– Side effects!!

– Cost-benefit ratio

Distribution

• Focal such as flexed elbow, extended

toe, clonus

• Multifocal: several joints in the same

limb

• Regional: spastic diplegia (mostly legs

but some arms as seen in CP)

• Generalized: diffuse

Treatment Management

• Utilizing the most conservative approach – Least side effects and most cost effective

• Progression from simple to complex

interventions: – Remove noxious stimuli Rehabilitation therapy Oral

Rx Neurolysis/Muscle Paralysis Surgery

Rehabilitation Interventions

• Positioning on a consistent basis

– Bed, WC

• Modalities

– Heat, Cold, E-stim, Biofeedback

• Therapeutic exercise

– Stretching, Hydrotherapy

• Orthotics, bracing, serial casting

Serial Casting • Series of casts to reduce spasticity

– Increase soft tissue and/or muscle lengthening

• Can use Tardieu scale to know how much range one can achieve

• Go to end range then back off slightly to help improve tolerance to cast

• Remove first cast in 24 hours to check skin

• Subsequent casts every 2-3 days

• Can bivalve

• Stop when no improvement noted in 2 consecutive casts

• Can use injections first to augment stretch

Pharmacological Treatments

• Baclofen

• Benzodiazepines

• Alpha-2-agonists

• Dantrolene sodium

• Others – Cyproheptadine

– 4-aminopyridine

– TCAs

– Gabapentin

– Opioids

– Cannabis

Oral Baclofen

• GABA-b selective agonist

• Decreases release of excitatory transmitters

• First line agent for spinal spasticity

• Dosage 5-80mg/day as per the PDR

• Equivalent to diazepam in efficacy but less

sedation

• Avoid sudden withdrawal seizures,

hallucinations, rebound spasticity

Clinical Effects of Baclofen

• Decreases seen in:

– Spasms

– Hypertonia

– Clonus

– Pain

– Bladder issues

• Side effects:

– Sedation

– Weakness

– Nausea

– Ataxia

– Confusion

– Decreased seizure

threshold

– Weight gain

Benzodiazepines

• Binds to GABA-a receptors – Facilitates post-synaptic effects of GABA resulting in

enhanced pre-synaptic inhibition

• Effective in painful spasms

• Long and short acting meds

• Doses – Diazepam: start at 1-5mg BID, max 60mg/day

– Klonopin: 0.5mg-1mg at bed time for nocturnal spasms

Benzodiazepines

• Benefits

– Decreases

hyperreflexia

– Decreased painful

spasms

– Good for bedtime use

– Decreases anxiety

• Side effects

– Sedation

– Fatigue

– Weakness

– Confusion

– Can slow cog recovery

– Depression

– Ataxia

– Incoordination

– Potential for

dependency, abuse

Dantrolene Sodium

• Works directly on muscle – Prevents Ca release from SR

– Effects normal as well as spastic muscles (weakness)

– Less likely to cause sedation

• Indicated primarily in supraspinal spasticity

• Initial dose 25mg TID

• Max dose 100mg QID

• Monitor LFTs: – Before starting, during titration and after stable dose reached

Alpha-2 Agonists

• Clonidine

• Tizanidine

Clonidine

• Transdermal delivery – Also oral

• Benefits – Decreased spasticity, clonus, hyperreflexia

– Change patch weekly

– May enhance coordination (mobility)

• Side effects – Hypotension

– Fatigue

– Decreased intellectual function

– Skin reaction

Tizanidine

• Peak plasma concentration in 1-2 hours

• Start at 1-2mg QHS

• Max dose 36mg/day

• Better tolerated in QID dosing

• Most common side effects: – Dry mouth, somnolence, dizziness

• Most serious side effects: – Hallucinations, elevated LFTs

• Monitor pts on oral contraceptives

• Contraindicated with Cipro or Luvox

Cyproheptadine

• Antihistamine, antiseratonergic and mild anticholinergic activity

• Blocks post-synaptic denervated supersensitive spinal receptors

• Benefits

– May enhance coordination, i.e. improved gait mechanics

• Side effects – Fatigue, weight gain, psychosis

• Dosage: – Initiate at 4mg QHS

– Up to 36mg/day

– Most common: 16mg/day in divided doses

Other Medications • Gabapentin

– Small studies in MS and SCI

– Improved spasticity with higher doses: 1200-3600 mg/day in divided

doses

• Pregabalin

• Cannabis

• Opioids

• 4-aminopyridine

• Alcohol

Injections

Targets local

spastic muscles

by blocking:

• nerve supply

• muscle activity

Injections

Benefits:

• Reversible

• Temporary

• Titratable

• Can be used with other therapies

• Local treatment w/o systemic side effects – i.e., no fatigue, memory effects, or slowed thought

• Restores balance between agonists and antagonists

Goals of Injections

• Diagnose contracture

• Facilitate therapy and function – Increase passive and active ADL’s

– Improve fitting of braces

– Ease of care

• Clinical benefits – Decreased pain

– Prevent or delay complications

– Reduce disfigurement

Anesthetics and

Chemodenervating Agents • Local anesthetics short-duration diagnostic block

(2-8 hours) – Lidocaine

– Bupivacaine

– Etidocaine

• Neurolysis long-duration (3-12 months) – Phenol (3-7% dilution)

– Alcohol (35-60% dilution)

• Neuromuscular junction block long-duration (3-6 months) – Botulinum toxin A

– Bolulinum toxin B

Alcohol/Phenol Injection • Dehydrated alcohol (35-60%)

• Phenol (3-7%)

• Clinical uses: – Motor nerve block

– Motor point block (IM injection)

• Localize injection site using electrical stimulator

• Immediate effects

• Variable duration of effect

• Most common nerves – Musculocutaneous, median, obturator, femoral, posterior tibial

• Complications – Pain, dysesthesias, tissue fibrosis

Alcohol/Phenol:

Adverse Effects

• Acute: brief burning/pressure during injection, inflammation, skin irritation and rare systemic side effects

• Subacute: if mixed sensorimotor nerve injected, can see pain and dysesthesias lasting several weeks; rare risk of soft tissue necrosis

• Chronic: induration, tender nodule formation, tissue fibrosis

Botulinum Neurotoxin

• 7 serotypes

– A to G

• Only types A and B are currently available

– Multiple products for type A

– Not interchangeable

– Different preparations

– Different side effect profiles

Botulinum Toxin

• Acts presynaptically to prevent the release

of ACh

• Onset of effect 24-72 hours

• Peaks at 2-6 weeks

• Average duration = 3 months

• Nerve sprouts and reinnervates

• Can be used in conjunction with other

treatments

Botulinum Toxin Injections

• Techniques – Motor point with EMG guidance

– E-stimulator

– Ultrasound

– Anatomic landmarks

• Adverse effects – Short intervals between injections and higher doses may

increase Ab formation

• Recommend: – Injection at 3 month intervals

When to turn to

Intrathecal Baclofen

• Spasticity not

responding to oral

meds

• Intolerable side

effects from oral

meds

• No alternatives left

except for surgery

SynchroMed Infusion System

• Pump – Infuses drug at programmed rate

• Catheter – Delivers drug to intrathecal (subarachnoid) space

• Programmer – Allows for precise dosing

– Easily adjustable dosing

Advantages of ITB Therapy

• Non-destructive

• Reversible

• Potential for fewer systemic side effects

• Programmable

• Dose can be titrated to optimal effect

Pharmacokinetics

• Intrathecal

– 600 mcg/day dose: 1.24 mcg/ml IT lumbar

concentration

– Lumbar to cervical concentration is 4:1 b/c of

molecular weight

– Half-life is 4-5 hours

• Oral

– 60mg dose: 0.024 mcg/ml IT lumbar concentration

– Half-life 3-4 hours

Post-Operative Phase

• Begin concentration at 500mcg/ml

• Can increase dose after 24 hours

– 10-15% per day as needed

• Maintenance dose = 300-1500 ug/day

Complications

• Overdose

• Underdose

• Infection

• Pump failure

• Pump dislodgement

Emergency Procedure:

Overdose

• Signs of overdose: seizures, sedation, weakness

• Maintain ABCs and provide supportive care

• If applicable, empty pump reservoir to stop drug flow and record amount withdrawn

• Physostigmine controversial for treating sedation or respiratory depression

• If LP is not contraindicated, withdraw 30-40ml CSF to decrease baclofen concentration – can be done via access port as well

Emergency Procedure:

Under Dose • Sign of rapid withdrawal: seizures, autonomic dysfunction,

hallucinations, rebound spasticity, itching

• Always make sure your patients have a supply handy of oral baclofen

(or benzo) should they pass their alarm date or miss refill appointment.

– may even need IV medications

• Treat seizures accordingly

• Supportive care

• Rapidly refill or reprogram pump

• Investigate pump for cause of possible failure

• Have meticulous system in place to avoid alarms

Surgical Treatments

• Neurodestructive

– Neurectomy

– Myelotomy

– Rhizotomy

– Cordectomy

– Selective dorsal

rhizotomy

• Orthopedic

– Tenotomy, Tendon lengthening, Myotomy, Tendon

transfers

SPLATT Procedure

• Split Anterior Tendon Transfer

• Treatment of equinovarus deformity of the

foot – Foot is PF (due to spastic GSC) and inverted and

supinated (due to spastic TA)

• Usually in conjunction with achilles tendon

lengthening

• Makes the TA a neutral inverter

Selective Dorsal Rhizotomy

• Procedure – Surgeon intraoperatively determines which rootlets

cause the spasticity

• Via EMG and careful dissection

– Selectively cuts these rootlets

• Two primary goals 1. Facilitate patient care: sitting, dressing, transfers

2. Improve function: walking

Thank you!

Jaime.levine@nyumc.org