Spasticity

Spasticity is a muscle disorder characterized by tight or stiff muscles and an inability to control those muscles. Reflexes may persist for too long and maybe too strong (hyperactive reflexes). The muscles remain contracted and resist being stretched, thus affecting movement, speech, and gait.

Spasticity usually is accompanied by paresis and other signs, such as increased stretch reflexes, which collectively are called upper motor neuron syndrome.

Paresis mainly affects distal muscles, with loss of the ability to perform fractionated movements of the digits

What Causes Spasticity? Spasticity is generally caused by damage or disruption to the area of the brain and spinal cord that are responsible for controlling muscle and stretch reflexes.

In other words – due to an imbalance of signals from the central nervous system (brain and spinal cord) to the muscles, these disruptions causing muscles to lock in one place.

Spasticity can be a symptom of a variety of conditions and diseases, including:

• brain injury

• spinal cord injury

• stroke

• cerebral palsy

• multiple sclerosis (MS)

• amyotrophic lateral sclerosis (ALS, Lou Gehrig’s disease)

• hereditary spastic paraplegias

• adrenoleukodystrophy (ALD)

• phenylketonuria

• Krabbe disease

Spasticity has several characteristics that differentiate it from rigidity:

1. Velocity dependence

2. Clasp Knife Phenomenon: Limb initially resists movement and then suddenly gives way

3. Distribution: Antigravity muscles being more affected

4. Stroking Effect: Stroking the surface of the antagonist’s muscle may reduce tone in spasticity.

Diagnosis The diagnosis of spasticity should involve a thorough medical history and physical examination, focusing on potential causes for the symptoms, to make the right diagnosis and management recommendations.

Essential factors to be considered include any traumatic events that may have affected the CNS, changes in medications, noxious stimuli, and intracranial pressure changes.

Additionally, electromyography (EMG) can provide valuable information about the velocity of nerve conduction, magnetic resonance imaging (MRI) scans can help to visualize causative damage in the central nervous system.

The severity of the condition can be classified according to a clinical scale, such as the Ashworth Scale, Tardieu Scale, Physician’s Rating Scale or the Spasm Scale.

Management Interventions for spasticity may vary from conservative (therapy and splinting) to more aggressive (surgery); most often, a variety of treatments are used simultaneously or are employed interchangeably.

Treatment options do not need to be used in a stepladder approach. Neurorehabilitation comprises four main categories of spasticity management targets.

1. Client care: Preventing or treating contractures; preventing or treating pressure areas; proper positioning of the body on the bed/wheelchair; easy orthotics fitting.

2. Movement improvement: The unmasking of voluntary movements previously covered by significant spasticity in cases of incomplete lesions; accelerating the “spontaneous” recovery process; modifying the “immature” motor pattern; using new recovery techniques to promote guided neuroplasticity, e.g. robotic rehabilitation; new functional pattern in moving and walking.

3. ADL’s: transfers, getting around, putting on clothes, personal hygiene, driving, etc.

4. Quality of life: Independent living; social and professional reintegration Current spasticity management options include the following:

• Therapeutic interventions (physical therapy, occupational therapy, hippotherapy, aquatics) and physical modalities (ultrasonography, electrical stimulation, biofeedback)

• Positioning/orthotics (including taping, dynamic and static splints, wheelchairs, and standers)

• Oral medications (such as baclofen, dantrolene, etc.)

• Injectable neurolytic medications (botulinum toxins and phenol)

• Intrathecal baclofen

• Surgical intervention (including selective dorsal rhizotomy and orthopedic procedures)

Physiotherapy Spasticity is one of the components of the UMN syndrome. Still, it should not be considered in isolation when it comes to management strategies.

Management targets must function and is always patient-focused rather than aimed at reducing the degree of spasticity.

• Progressive Resistance Strength Training.

• Biofeedback combined with functional electrical stimulation and occupational therapy.

• Nabiximols (a specific Cannabis extract ) effectiveness in MS-related spasticity combined with a PT program may improve overall response to the reduction in spasticity.

• Shock wave therapy on flexor hypertonic muscles.

• Continuous ultrasound therapy over a 5-week period (frequency 1MHz and intensity 1,5 W/cm2).

• Cryotherapy, using cold packs (12°C) for 20-minutes.

• Electric Stimulation using agonist stimulation showed a significant improvement in Ashworth Scores, while antagonist stimulation showed an increase of stretch reflex-initiating angle.

Pharmacological

If spasticity is widespread then systemic medication is used.

This includes:

• Dantrolene (Dantrium)

• Baclofen (Lioresal and others) • Tizanidine (Zanaflex)

• Diazepam (Vallium) If the spasticity is locallised then local medication is used. This includes:

• Boutulinum Toxin (Botox)

• Baclofen (Inrathecally – High concentration more locally).

• Phenol / Nerve Block Surgical procedures are also indicated in some circumstances to correct the positioning of tendons or nerve pathways.

Intrathecal baclofen therapy (ITB) may be used in severe cases, which involves direct administration of baclofen to the spinal cord, thus reducing the risk of systemic side effects.

Orthopedic surgery or neurosurgery can also help to remedy changes to the muscles, bones, connective tissue or nervous system.