Parkinson’s disease (PD) is the second most common degenerative brain disorder, after Alzheimer’s disease (Morris, 2000). It is common among older people, affecting approximately 1.5 to 2.0% of people aged 60 years and older (Sweeney, 2013). Due to the aging population, it is predicted that by the year 2020 more than 40 million people worldwide may have this disease (Morris, 2000).
PD is primarily associated with the gradual loss of dopaminergic neurons in the substantia nigra pars compacta of the brain (Erikson et al., 2005). Dopamine is a chemical messenger that transmits signals in the nigrostriatal pathway to coordinate and regulate muscle activity (Mandal, 2009). Loss of dopaminergic neurons demands greater exertions of effort for any given movement. Thus the patient is unable to direct or control movement (Mandal, 2009). . A degeneration of 80% of neurons is estimated to occur before signs of the disease become evident (O’Sullivan & Schmitz, 2001). Besides the loss of dopaminergic neurons, PD is also characterized by the accumulation of α-synuclein proteins into inclusions called Lewy bodies in the substantia nigra pars compacta (Erikson et al., 2005). Lewy bodies are the pathological hallmarks of PD. Although the exact cause and pathogenesis of the depletion of dopamine and the presence of Lewy bodies in PD are unknown, the condition likely results from both environmental risk factors and genetic factors (Mandal, 2009).
Clinical presentation of PD may vary between individuals. The typical motor symptoms of the disease include difficulty in initiating movement (akinesia); reduced movement speed in amplitude (bradykinesia); stiffness in arms, legs, and trunk (rigidity); postural instability and resting tremor (Keus et al.,2007). In addition secondary impairments of the disease include the development of abnormal fixed postures, fatigue, contractures, swallowing and communication difficulties, cognitive and behavioral dysfunction, and visual and sensorimotor disturbances (O’Sullivan & Schmitz, 2001).
PD is a chronic and progressive disease with a major impact on patients’ lives. It can severely compromise an individual’s ability to perform daily activities such as transfers, posture, balance, and walking. This can lead to increased dependence on others, falls, injuries, resulting in social isolation reduced quality of life (Keus et al., 2007). Physical therapy can reduce disability among patients to enhance their quality of life. Although it cannot cure the disease, it can improve daily function by teaching and training patients in the use of movement strategies (Keus et al., 2007). Furthermore, physical therapy can reduce secondary health problems by maintaining musculoskeletal and cardiovascular systems in optimal condition (Kwakkel).
When planning or managing physical therapy interventions, physical therapists should focus on patient’s history, stage of disease and symptoms, areas of functional deficit, and residual abilities and...