Spasticity - part 3 ( braddom 5th edition )

SPASTICITY - PART 3 ( BRADDOM 5TH EDITION )

EDITED BY ME

SIGNS AND SYMPTOMS

1 Muscle tightness or the limb cannot be moved

2 functional limitations -

A ) inability to release a grasped object

B ) difficulty in walking

C ) weakness

D ) difficulty in manipulating objects due to decreased hand dexterity

E ) inability to perform certain tasks

OFTEN WEAKNESS RATHER THAN SPASTICITY IS THE PRIMARY CAUSE OF LIMITATION

PROBLEM IDENTIFICATION AND GOAL SETTING

1 For this , there should be knowledge of abnormal postural pattern - are manifestations of imbalance

2 ARE THE GOALS SMART

S - specific ( well defined and targets a specific problem )

M - measurable ( either quantitatively ( technical ) or qualitatively ( functional )

A - agreed upon

R - realistic ( potential for improvement )

T - TIME BOUND

Or

SMARTER

E - EVALUATED

R - REEVALUATED

CLINICAL TESTING OR DIAGNOSIS

ASHWORTH SCORE

MODIFIED ASHWORTH SCORE

TARDIEU SCALE

REPAS SCALE ( IS BASED ON ASHWORTH AND MOD ASHWORTH TESTING ) - also kn as resistance to passive movement scale

DEFINITION

IS DEFINED AS VELOCITY DEPENDENT INCREASE IN TONIC STRETCH REFLEXES ( V IMP )

It occurs secondary to -

1 Increased non reflex intrinsic muscle stiffness

A ) Length dependent are secondary afferents whereas primary afferents are velocity dependent

B ) Velocity dependence was greater at greater muscle lengths and length was greater with faster stretches ( vice versa )

OVERALL , stretch responses are both velocity dependent and length dependent ( v imp )

NOW IT IS ALSO KNOWN THAT IT IS POSITION DEPENDENT ( VV IMP ) - PAY ATTENTION WHILE EXAMINING .

MANAGEMENT

A ) NON PHARMACOLOGICAL

1 - VV IMP - ALTHOUGH SPASTICITY IS A NEUROLOGICALLY BASED CONDITION , ITS OBVIOUS MANIFESTATION IS PHYSICAL , SO USE OF PHYSICAL MODALITIES

2 Passive stretching - effective in reducing tone and increasing ROM in patients with brain injury

3 use of splinting and casting in acute setting for sustained contractions - casting alone is sufficient to prevent contracture and to reduce spasticity if done earlier

4 electrical stimulation - only temporarily

B ) PHARMACOLOGICAL

1 APPROACH - 2 TYPES

A ) Base drug choice on the clinical presentation - no of limbs involved

B ) Determine the choice of drug on underlying pathophysiology of spasticity - according to neuroanatomical basis

DRUGS

A ) oral spasmolytics -

most commonly used are -

1 - Baclofen ( GABA B AGONIST )

2 - Tizanidine ( ALPHA ADRENERGIC AGONIST )

3 - Dantrolene ( HYDANTOIN DERIVATIVE )

4 - Benzodiazepines ( GABA A AGONIST )

5 - Gabapentin ( inhibitor of voltage gated calcium channels )

A ) These all are associated with adverse effects such as - sedation , drowsiness and weakness - vv imp ( VIVA IT OCCURS SECONDARY TO POOR ADHERENCE )

B ) THERE IS NO EVIDENCE BASED GUIDELINES - medicine choice is based on practical reasons

C ) A medicine should be allrounder or having patient related property *

Eg - use of tizanidine which also has analgesic properties along with spasmolytic activity can be used in painful nocturnal spasms - it also promotes sleep - BUT IT CANNOT BE GIVEN IN ORTHOSTATIC HYPOTENSION OR PATIENT TAKING CLONIDINE

D ) INJECTION SHOULD BE USED IN BRAIN DAMAGE PXS SINCE ORAL DOSING CAN CAUSE MORE SEDATION

OR

COMBINATION MEDICATION AT LOWER DOSE SHOULD BE USED

E ) DONOT ABRUPTLY STOP A DRUG - DONOT STOP BACLOFEN ABRUPTLY AS IT CAN CAUSE REBOUND SPASTICITY AND HALLUCINATIONS

F ) TIZANIDINE SHOULD NOT BE GIVEN WITH FLUOROQUINOLONES AS IT CAN INCREASE ITS LEVEL

G ) TIZANIDINE CAUSES DOSE DEPENDENT ANTI NOCICEPTIVE EFFECTS AS IT CAUSES INHIBITION OF SUBSTANCE P.

B ) FOCAL TREATMENT - BOTULINUM TOXIN CHEMODENERVATION

1 - it exerts its action through inhibition of acetylcholine release at NM junction

2 - it takes several days following an injection and its a complex process -

A ) internalisation of the toxin

B ) reduction and translocation of disulfide bonds holding the light and heavy chains of the toxin

C ) inhibition of acetylcholine release - cleaving of SNARE protein ( sensitive n ethylmaleimide sensitive fusion attachment receptor )

3 DOSING -

600 - 800 UNITS ARE SAFER ( Incobotulinum toxin A and onabotulinum toxin A )

4 DILUTION - high volume or end plate targeted botulinum toxin result in more profound neuromuscular blockade than low volume - its a double edge sword as it can leads to reversible paralysis of non affected area or muscle group - OPTIMAL CONCENTRATION IS REQUIRED

5 ENHANCEMENT TECHNIQUES

1 Target the muscle innervation zone not just the motor points ( v imp ) can optimise the effects of botulinum toxin innervation

2 guide injection by listening to EMG activity

3 identify motor points through electrical stimulation

4 visualising target sites by sonography

5 role of casting ( v imp - practical point of view ) enhances the effects of onabotulinum toxin A owing to prolonged stretching of spastic muscles

6 pairing with electrical stimulation - influences the activity of synaptobrevin 2 receptors - it facilitates neuronal binding and subsequent uptake of botulinum toxin ( v imp )

7 Pairing with extracorporeal shock wave therapy - recently through modulation of muscle rheology and neurotransmission

POTENTIAL REASONS FOR POOR OUTCOME ( VV IMP - VIVA VOCE )

1 PATIENT RELATED -

A ) age and size

B ) disease condition

C ) concurrent medications that can interact with spasmolytics

D ) unrealistic goals

2 - INJECTOR RELATED

A ) incorrect diagnosis

B ) incorrect muscle selection

C ) improper injection technique

3 DRUG RELATED

A ) incorrect dose

B ) incorrect preparation

C ) FOCAL PHARMACOLOGICAL TREATMENT ( NERVE BLOCK - NEUROLYSIS )

1 By phenol ( 5 - 7 % ) or alcohol ( 35 to 60 % ) - denatures proteins ( v imp ) in neural tissues leading to blockage of nerve transmission

2 causes degeneration of muscle spindles , damage to both afferent and efferent nerve fibers - is irreversible - leads to permanent control of spasticity

3 is also an anesthetic at low concentrations - less than 3 %

4 effect is immediate

5 commonly injected nerves are - pectoral , subscapular , musculocutaneous , obturator and tibial nerve

6 side effects - injection related dysesthesia , localised swelling , excessive weakness , hypotension , tremor and convulsions

D ) INTRATHECAL BACLOFEN

1 - has the advantage of direct access to GABA B receptors in spinal cord because the BBB has not to be crossed for this

2 - decreases the oral related adverse effects

3 to be used in severe spasticity OR severe dysautonomia following brain injury , when other Rx fails

4 trial should be done and is defined as 1 to 2 drop in modified ashworth score - the recommended trial dose is 50 micrograms

5 - most common drug related side effect is hypotonia , somnolence , headache , convulsions , dizziness and urinary retention

E ) SURGICAL INTERVENTION - LAST RESORT

1 is well accepted treatment option for contractures as it primarily address joint deformities rather than spasticity itself

2 includes neuroablative procedures such as rhizotomies , peripheral neurotomies and orthopaedic reconstruction procedures such as tendon lengthening and tendon transfers

3 commonly performed tendon procedures are - SPLATT ( SPLIT ANT TIBIAL TRANSFER ) , achillis tendon lengthenings for managing spastic equinovarus - specifically corrects the abnormal joint positioning by providing a new position