Neuropathies
Neuropathies involve dysfunction of the peripheral nerves, which consist of: motor neurones, that carry the electrical signals directly from the spinal cord and brain stem to activate muscle movement; the sensory neurones, which convey sensory information such as pain, temperature, light touch, vibration and position to the brain; and the autonomic neurons, which go to the internal organs and control blood vessel reflexes.
Neuromuscular junction disorders
Myasthenia gravis and Lambert-Eaton syndrome are examples of neuromuscular junction disorders. Muscular dystrophies and inflammatory myopathies such as polymyositis are examples of primary muscular (myopathic) disorders.
Neurodegenarative classification encapsulates the progressive loss of structure or function of the neurone and a number of conditions exhibit this form of progression. Hence, amyotrophic lateral sclerosis (ALS), Parkinson's and Huntington's are classified as neurodegenerative diseases that affect movement. These conditions exhibit characteristically slower movement compared to healthy people – hypokinesis – or excessive and abnormal involuntary movements – hyperkinesis [156]. Some common examples of hypokinesis include bradykinesia, freezing, rigidity and stiff muscles, while those belonging to hyperkinesis are chorea, dyskinesia, myoclonus, tics and tremor [242].
The most common neurological [215] and adult movement disorder, essential tremor (ET), is about 20 times more prevalent than Parkinson's disease itself. Patients with ET are likely to have tremors with 4–12 Hz and the risk factors associated with this are age, ethnicity and family history [215]. The condition affects the performance of work-related tasks and activities of daily living (ADLs) and a number of medical and physical rehabilitation approaches are in use as treatments for the condition [39, 295].
An estimated 7 to 10 million people worldwide are living with the second‐most common neurodegenerative disorder, Parkinson's disease (PD) [90]. Approximately 60 000 Americans are diagnosed with PD each year while in western Europe this figure is 160 for every 100 000 over the age of 80 [89]. In China, approximately 1.7 million above the age of 55 [396] are suffering from the condition. The movement disorders experienced by a PD patient can be classified into three stages [244]. In the initial stage, the patient may exhibit a forward stooped posture, festinating gait, rigidity, etc. During the first 10 years of PD, characteristic movements such as resting tremor, hypokinesia and micrographic handwriting are common. During the later phase, patients may exhibit dyskinesia, akinesia, postural instability, etc. In terms of treatment, various kinds of medical therapies, such as levodopa, as well as surgical approaches and deep brain stimulation are utilised to control symptoms in addition to physical rehabilitation therapies [171].
Although these two conditions are common and have a significant impact on the quality of life, they are not fatal diseases. In contrast, stroke is one of the most fatal conditions in developed countries [374]. However, a majority of stroke suffers may be alive after the initial injury, albeit losing some motor functions lifelong or for a prolonged period of time [193]. In 2005, there were 5.7 million deaths in low‐ and middle‐income countries due to stroke, which has increased significantly to 6.5 million and 7.8 million, respectively, in 2015 [338]. Age, gender, race, ethnicity and heredity are considered as important markers of risk factors [273], while hypertension, cardiac disease, diabetes, glucose metabolism, lipids, cigarette smoking, alcohol, illicit drug use, lifestyle, etc., are considered to have an adverse influence on the likelihood of stroke [273]. Similar to other disorders, physiotherapy is widely used as a rehabilitation therapy to assist stroke patients to regain physical functionality [291].
Such a complex locomotor and neural system are frequently influenced by various injuries and disorders. Therefore, a number of approaches have been explored to treat people suffering from conditions leading to abnormal movements and even disabilities. Among these methods, physical rehabilitation is commonly utilised to assist patients in recovery and reacquire ADLs.
Defined as “the treatment of disease, injury, or deformity by physical methods such as massage, heat treatment, and exercise rather than by drugs or surgery” [279], physiotherapy (also known as physical therapy) has been applied in clinics for thousands of years. A number of therapies are included in physical therapy, such as mechanotherapy, hydrotherapy, balneotherapy and so on [349], among which mechanotherapy was documented as early as the 1840s. In recent decades, physical therapy has been applied extensively for various musculoskeletal injuries and neurological movement disorders [107, 142]. The detailed examples can be found in Section 1.2.
Although traditional physical therapy has shown its effectiveness for the rehabilitation of physical functions of patients with movement disorders [95], a series of drawbacks can also be observed [9, 57], which are summarised as follows.
These rehabilitation programmes are “boring” and patients are demotivated by these repetitive exercises.
Computerised sensing techniques are not involved in these programmes, which may lead to incorrect interpretation of observed data.
A one‐to‐one form of delivering rehabilitation services makes conventional rehabilitation very inefficient and costly.
Costly equipment is required by traditional rehabilitation therapies.
Insufficient funding for rehabilitation services results in making access to these services unaffordable.
The workforce in the rehabilitation field is inadequate in number.
Rehabilitation centres are usually distributed in urban areas, while a large number of people needing rehabilitation services live
