The impact of exercise on postural control in patients with Parkinson's disease measured by computerized dynamic posturography
Abstract
Postural instability (PI) is one of the most debilitating symptoms of Parkinson's Disease (PD) that onsets in early stages of disease. The pathophysiology of PI occurs because of complex sensorimotor dysfunction that is not medically mediated by dopaminergic pharmaceutical agents. Exercise interventions that incorporate progressive resistance training (PRT) and tasks of high motor-complexity have been shown to positively impact motor symptoms of PD, including PI. Several standardized balance assessments and technologies have been validated to assess postural control; however, current literature is inconclusive regarding what standardized tools most accurately quantify PI. We hypothesized that individuals with PD who exercise regularly would show better performance outcomes measured by computerized dynamic posturography (CDP), balance, and physical function, in comparison to sedentary controls. METHODS: Thirteen individuals with PD who participate in the Rock Steady Boxing Program (EX= 70.1[plus or minus]6.1 yrs, H&Y stage 1.5[plus or minus]0.52, 207.7[plus or minus]56.7 min structured exercise/week) and twelve sedentary controls, also diagnosed with PD (SED= 68.5[plus or minus]5.02 yrs, H&Y stage 1.7[plus or minus]0.49, 0 min structured exercise/week) participated. Individuals underwent a single-session CDP testing battery: sensory organization (SOT), motor control (MCT), toes up/toes down adaptations (ADT), and limits of stability (LOS). The Modified Fullerton Advanced Balance scale (MFAB) and the 4-stage CDC (4CDC) were used to assess clinical balance. RESULTS: Between-group CDP analysis did not detect differences in performance on SOT, ADT, MCT, or most variables of LOS. Exercisers had faster reactions to horizontal translations (EX= 139.7[plus or minus]10.75 msec, SED= 150[plus or minus]13.5 msec, p<0.05) and more directional control (71.08[plus or minus]5.34 percent) than sedentary controls (64.6[plus or minus]7.6 percent, p=0.022). No betweengroup differences were detected in SOT or ADT performance. Exercisers showed better dynamic balance on the MFAB (EX= 33.5[plus or minus]3.3, SED= 25.8[plus or minus]4.5, p<0.01) and static balance reported by the 4CDC (EX= 38.5[plus or minus]2.48, SED= 31.3[plus or minus]5.6, p=0.002) compared to controls. CONCLUSION: CDP was unable to detect differences in balance performance between exercisers and sedentary individuals with PD. Clinical balance assessments, the MFAB and 4CDC, showed the exercising individuals to have better dynamic and static functional balance than sedentary controls. These findings suggest that CDP is not an ideal tool to assess exercise-induced changes in functional balance performance and PI in PD.
Degree
M.S.