A new therapeutic approach in physical medicine and rehabilitation
Botulinum toxin is a molecule produced in nature by the bacteria clostridium botulinum. Although in high doses this toxin is lethal to humans (the reason for it being called a toxin), at low doses it has been discovered to have very useful therapeutic applications!
There are seven types of toxins from A to G, however the one that has greater therapeutic application is botulinum toxin type A. It already exists on the market and is commercialised under different brand names.
Botulinum toxin acts as a neurotransmitter at the neuromuscular junction causing muscle paralysis. Its effect lasts from three to six months.
Botulinum toxins now play a very significant role in the management of a wide variety of medical conditions, as it relaxes clenched muscles. This neurotoxin acts on all neurological diseases where there is excessive muscle contraction, namely dystonia and spasticity in: cerebral vascular accident, multiple sclerosis, traumatic brain injury, spinal cord injury, cerebral palsy, spastic paraparesia, lateral sclerosis amyotrophic and cervical dystonia.
Other applications of Botulinum toxin are the reduction of sialorrhea (excessive production of saliva in degenerative brain diseases), chronic headache and some types of muscular contractures by inhibiting the release of pain.
Despite its various medical applications, there are absolute contraindications as to its application, due to the risk of developing antibodies, as is the case with some neuromuscular diseases, pregnancy or breastfeeding, local skin or muscle infection and a previous application of botulinum toxin (less than three months). Adverse reactions are rare, transient and self-limiting when applied by experienced physicians.
It is important to point out that people who suffer from the above mentioned pathologies and after botulinum toxin application should integrate a rehabilitation programme with an experienced multi or interdisciplinary team, able to apply different techniques:
■ Physiotherapy: proprioceptive neuromuscular facilitation (PNF), balance training, gait training, muscle strengthening, muscle stretching, hydrotherapy, functional electrical stimulation (FES);
■ Occupational therapy: perceptual-cognitive training, training in domestic daily activities, training for leisure activities, technical aids, games, computer, orthotic fitting and training, wrist and hand mostly training, training on wheelchair mobility and driving;
■ Daily living activities: hygiene, self-care/grooming, dressing, bed mobility, transfers (t.board, t.disk, t.elevator), support bars;
■ Orthotist: provision of various aids, such as removable splints for the support of joints and limbs in positions as physiological as possible;
■ Serial casting (doctor + nurse or physiotherapist/occupational therapist): the joint is placed in a plaster cast to prevent contractures and excessive muscle stiffness, sometimes used immediately after botulinum neurotoxin injections.
All these professionals, as well as psychologists, play a crucial role in providing education/advice/moral support to patients and caregivers affected by a congenital or acquired condition which affects the central nervous system, resulting in impairment with spasticity.
For botulinum toxin application, the patient needs to be seen by a specialist in physical medicine and rehabilitation to evaluate its indications and contraindications as well as the patient functional condition.
Botulinum toxin is applied by a specialist in physical medicine and rehabilitation at the Hospital Particular do Algarve.
By Dr Luis Malaia
Dr Luis Malaia is a specialist in physical rehabilitation at Hospital Particular do Algarve.