Spasticity is a disorder characterised by an increase in muscle tone and exaggerated tendon reflexes – it mat be both a presenting feature and also a complication of neurological disease. Spasticity impacts on function, comfort and is a cause of disability.
Spasticity is part of upper motor neuron lesions (eg cerebral palsy, multiple sclerosis, traumatic brain injury, stroke, spinal cord injury). Positive symptoms of UMNL include spasticity (increased muscle tone, exaggerated tendon jerks, stretch reflex to spread to extensors, clonus) and released flexor responses (Babinski response and mass synergy patterns). Negative symptoms include loss of finger dexterity, weakness and loss of motor control of selective muscles.
Ashworth Scale for the Grading of Spasticity :
0 No increase in muscle tone
1 Slight increase in muscle tone, manifested by a catch and release or by minimal resistance at the end of range of motion when the affected part(s) is moved in flexion or extension
1+ Slight increase in muscle tone, manifested by a catch, followed by minimal resistance throughout the remainder of the ROM
2 More marked increase in muscle tone through most of ROM, but affected part(s) easily moved
3 Considerable increase in muscle tone, passive movement difficult
4 Affected part(s) rigid in flexion or extension
• Benzodiazepines (increases affinity of GABA to its receptor; eg Diazepam)
• Baclofen (GABA agonist)
• Dantrolene sodium (acts peripherally; reduces calcium release from sarcoplasmic reticulum reduces muscle contraction)
• Tizanidine (central alpha-2 noradrenergic agonist; inhibits H-reflex)
Botulism toxin (BTX) – affects neuromuscular junction by inhibiting acetylcholine release; usually lasts 3-4 months on average)
Phenol and alcohol
• stretching (helps maintain a full range of motion; prevents contracture; needs to be done >1x day)
• strengthening (spasticity often leads to loss of strength, so this needs to be restored/maintained)
• positioning (proper positioning improves comfort and can reduce spasticity; eg bed position, wheelchair positioning)
• weightbearing (can reduce spasticity)
• cold/ice (cold can improve muscle tone, but only improves function for short term)
• casting (serial casting can be used to gradually stretch our a contracted limb)
• electrical stimulation (to stimulate a weak muscle to overcome power of the stronger spastic muscle)
• biofeedback (may be able to conscious reduce muscle tone)
Orthoses and splints:
• allow a spastic limb to be maintained in a more normal position (eg AFO can keep foot flexed)
After evaluation as to the ability to carry out activities of daily living may need education regarding special techniques and the use of special equipment.
Activities can be used to improve co-ordination, muscular strength and endurance and sensory education.