Humans can move, and skeletal muscles can function because of the concurrent collaboration between upper motor neurons, lower motor neurons, the neuromuscular junction, and the muscle itself. An impairment at any of these levels is defined as a neuromuscular disorder. Neuromuscular disorders can happen at any given moment and are not necessarily congenital, but the most common cause of physical disability in children is the non-progressive brain disturbance cerebral palsy, affecting 2-3 children out of 1000 live births. Acquired brain damage can be caused by traumas or cerebrovascular accidents, better known as strokes, and impacts 19.000 Belgian inhabitants and their families each year.
This article provides insight into the most common neuromuscular disorders, more specifically, how orthoses can be utilized in treatment and therapy.
Cerebral Palsy
The disease expresses itself in complications on three different levels, the primary, secondary and tertiary level. Problems related to the neuronal lesion lead to a lack of muscle strength, disturbed muscle tension known as tonus, selectivity and coordination difficulties, and disordered balance. All of the above are defined as primary problems. The bony deformities and fixed contractures arising from the primary issues in combination with a lack of movement and growth are defined as the secondary issues. Coping strategies to reduce primary and secondary problems are defined as tertiary problems.
An orthosis can offer support to the patient in each of these levels. In the past, treatment focused on the secondary level but nowadays, the cause of these problems is addressed. On the primary level, balance levels and the lack of muscle strength can be compensated with a lower limb orthosis. Severity determines the base of support, but the disturbed muscle tonus should be kept in mind when deciding what orthosis to implement. A more common approach is the integrated botulinum neurotoxin, a treatment, in which casting and orthosis are implemented post injection. From foot Orthosis to Trunk-Hip-Knee-Ankle-Foot orthosis, multiple types of mainly lower limb orthosis are used as functional or accommodative support.
Spina Bifida
Spina Bifida is a congenital neural tube malformation leading to an open or closed spinal dysraphism. The incomplete fusion of the spinal cord can occur at any height of the neural tube, leading to, e.g., Anencephaly or Encephalocele but most prevalent is the open spina bifida, Myelomeningocele. The level of the paralysis determines the prognosis for functional activity. Neurologic lesions at the sacral level, the least severe variant, can lead to foot deformities such as claw toes or cavovarus or a lack of strength in the gastrocnemius and intrinsic foot muscles. Integrating an ankle-foot orthosis can improve stabilization and increase normal function.
In the treatment of the lower lumbar level lesion, the lack of knee strength must be compensated as well. Together with the lurching gait and adequately strong hip muscles, the KAFO is the orthosis implemented in this treatment.
The higher the lesion, the more severe the consequences, lesions in the higher lumbar level thus result in more detrimental disturbances. For this level and thoracic lesions, the reciprocating gait orthosis leads to the most efficient walkers.
Duchene
A mutation in the dystrophin gene leads to recessive X-linked Duchenne’s muscular dystrophy, affecting 1 out of 3600 boys. The absence of dystrophin leads to muscle degeneration since it is a fundamental structural component for stability in the muscle tissue. The course of the disease is progressive, and life expectancy is only 25 years. Research is still ongoing since there is no curative treatment yet. Implementation of an orthosis in treatment leads to a higher life expectancy due to the postponed contractures resulting from muscle weakness.
Spinal muscular atrophy
In SMA muscles lose function due to a motor neuron defect. The motor neurons in the anterior horn of the spinal cord are affected due to the SMN1 gene, resulting from an autosomal recessive disease. Life expectancy varies from a few weeks to adult life depending on subtype, type I – Werdnig-Hofmann, type II – Dubowits, and type III – Kugelberg-Welander. The disease is not yet curable, but symptoms can be eased with several therapies, including orthoses. A common symptom is a growth disturbance of the vertebral column, known as scoliosis.
Cerebrovascular accident
A stroke is the third cause of death worldwide. Orthoses won’t prevent strokes, but four out of ten patients who survived a stroke encounter stroke-induced difficulties in their daily life. The life of 174.000 people in the Netherlands is affected by its consequences.
There are multiple physical disabilities caused by a cerebrovascular accident varying in severity, e.g., numbness, muscle weakness, incontinence, loss of eyesight and speech, etc. Muscle weakness and overall pain can be supported and respectively eased with the implementation of an orthosis.
Depending on the level of the lesion, as equally explained in the spina bifida section, an orthosis can be implemented to support the patient in his or her daily activities.
The contents of this article may not be used as a treatment prescription; they are written to offer an overall understanding of this topic. Always contact your general practitioner or doctor.
