Parkinson’s disease patients who have a tendency to fall use different strategies to control their balance than those who do not fall, according to a recent study.
The study, “Fallers with Parkinson’s disease exhibit restrictive trunk control during walking,” was published in Gait and Posture.
Due to Parkinson’s-related motor imbalance, falls are a common consequence of the disease, and the risk of falling increases as patients get older and as the disease progresses.
Parkinson’s patients are twice as likely to fall than older adults living independently, and are also nine times more likely to have recurrent falls.
Observational studies suggest these patients underestimate the amount of work necessary for their muscles to produce a certain movement. They compensate for this lack of motor and perceptual ability by adopting distinct postural strategies to keep their balance during both static and dynamic movements.
Static measures of posture control can distinguish Parkinson’s patients from healthy older adults, but not Parkinson’s fallers from non-fallers.
“A better understanding of the relationship between falls and static and dynamic movements may provide further insight into falls-risk assessment in this clinical population,” the researchers said.
To study this, researchers at the University of Ottawa in Canada conducted a study that recruited 25 Parkinson’s patients and 17 healthy older adults used as controls.
They analyzed postural differences between Parkinson’s fallers and non-fallers, based on the self-reported occurrence of falls in the previous three months, and between healthy controls.
Motor disability was measured using the Unified Parkinson’s Disease Rating Scale III, cognitive impairment by the Montreal Cognitive Assessment, and freezing of gait by the Freezing of Gait questionnaire.
Participants were given static and dynamic motor tasks, consisting of one quiet standing condition and one walking condition (walking 15 meters while looking straight ahead).
Both tasks were presented twice and lasted for 30 seconds. Testing was performed while patients were optimally medicated with dopaminergic therapies.
The standing test was sensitive enough to distinguish between Parkinson’s patients and healthy controls, but not between fallers and non-fallers with Parkinson’s disease. However, static tasks were less sensitive in differentiating between fallers and non-fallers with Parkinson’s disease and healthy older adults than dynamic tasks.
Fallers had difficulty controlling their upper body (torso) when walking, compared with non-fallers and the control group. This was also true for individuals with Parkinson’s disease versus older healthy adults.
Importantly, falling was associated with static and dynamic postural control in Parkinson’s patients, with fallers and non-fallers adopting different postural strategies to regulate balance.
“Overall, this study provides useful information for falls-risk assessments as well as for developing fall prevention program specific to fallers and non-fallers with PD,” the researchers concluded.