The Relationship Between Upper Extremity Function and Balance and Functional Mobility in Parkinson's Disease

Parkinson's Disease (PD) is the second most common neurodegenerative disease, affecting 2-3% of the population aged 65 and over, characterized by the loss of dopaminergic neurons. The basal ganglia play a significant role in the pathogenesis of PD. The lesions of the basal ganglia impair the ability of patients to perform complex, goal-oriented, and skill-requiring movements. Consequently, motor symptoms such as bradykinesia, rigidity, hypokinesia, and tremor, which are progressively worse, are added to the clinical picture of the disease. These symptoms, which cause movement and activity limitations in individuals with PD, also affect upper extremity functions, balance, and functional mobility. Impairment of upper extremity functions, commonly seen from the early stages of the disease, can affect many basic activities of daily living, including buttoning clothes, tying shoelaces, sewing, writing, eating, and using various modern devices. Balance and mobility disorders are among the most debilitating features of the disease, as they lead to the deterioration of physical functions in PD. Balance and mobility issues in PD are identified as key determinants of the increasing fear of falling and the resulting decline in quality of life. Various factors such as rigidity, bradykinesia, impaired postural adjustments, and decreased sensory integration contribute to the negative impact on balance and mobility in individuals with PD. Proper balance and mobility performance are achieved through synergistic control during both dynamic and static postures between proximal body segments such as the trunk, spine, and pelvis. This contributes to the mobility of distal segments and the functionality of the upper extremities. Additionally, the contribution of upper extremity functions to balance and mobility has been demonstrated in healthy populations. Current literature also reveals that treatment programs targeting the upper extremities can improve mobility and balance, especially in neurological patient populations. In conclusion, balance and mobility disorders in Parkinson's disease can reduce proximal stability and affect hand dexterity. This study aims to examine the relationship between hand dexterity, balance, and functional mobility in individuals with PD.