A deviation from the normal pattern of movement in walking. A number of gait disturbances characterize Parkinson’s disease. These all result from the disruption of communication among the neurons in the brain related to movement, caused by the depletion of the neuro-transmitter dopamine. As with other symptoms of Parkinson’s, gait disturbances affect people in different and various ways. One person with Parkinson’s may have severe and numerous gait disturbances as early symptoms while another has barely perceptible problems until much later in the course of the disease; gait problems severe enough to cause falls very early (within the first two years of symptoms) raises questions as whether another form of parkinsonism, such as progressive supranuclear palsy or multisystem atrophy may be the correct diagnosis. A person with Parkinson’s may have one gait disturbance or multiple problems with walking. anti-parkinson’s medications can control gait disturbances for most people during the early and mid stages of the disease, although in later stages these symptoms typically “break through” during off-state episodes, when the medications, particularly levodopa, are not effective. There is a general feeling that levodopa may be a slightly more effective medication for gait and balance problems than even high doses of dopamine agonists.
Gait disturbances ultimately affect everyone whose Parkinson’s becomes moderate to advanced as the brain’s ability to direct the functions of movement continues to deteriorate. The way this takes place varies greatly among individuals. A particular gait disturbance may become progressively more severe, or additional disturbances may develop. Freezing of gait, start hesitation, and shuffling are the most prevalent gait disturbances in Parkinson’s. Although these symptoms are involuntary, it does often help for the person to focus conscious attention and effort on the functions of movement. Because these functions have always occurred automatically (without conscious awareness), learning to focus in this way is frustrating, especially at first, for many people with Parkinson’s. As well, there is a point at which the damage from the Parkinson’s becomes extensive enough that it is no longer possible to “will” the body into movement.
Changing Direction (Turning)
Changing direction, or turning, becomes a challenge for many people with Parkinson’s and is a function of movement during which the risk for falling is high. In natural or normal movement, changing direction takes place as a pivoting action. In the stance phase of the gait cycle the foot plants, and the body shifts not only its weight but its direction of travel. This sequence of motions requires balance, equilibrium, and coordination all of which deteriorate as Parkinson’s disease progresses. The person with Parkinson’s attempts to accommodate the loss of these abilities by using small, shuffling steps to move in an arc when changing direction. This gait has the appearance of walking around an unseen obstacle. As the Parkinson’s becomes more severe, and during off-state episodes in which anti-parkinson’s medications cannot control movement, the span of this arc becomes wider and wider. Effort to shorten this span often results in loss of balance and falling.
Sometimes the person with Parkinson’s attempts to stop and then change direction. Often, however, this is no easier a combination of movements and results in other gait disturbances such as stop hesitation (difficulty in stopping) and start hesitation (difficulty in beginning the next movement). Movement specialists recommend that the person with Parkinson’s attempt to overcome turning challenges by planning directional changes and making them in a U-turn style, allowing for an adequate approach and wide arc or turning radius to minimize balance loss. This action, like other movement accommodations, requires focus and concentration.
The Latin origin of the word festination means “to hasten,” as a person with this gait disturbance appears to do. A festinating gait consists of short, increasingly rapid steps with a marked forward lean, as though the person is about to break into a run. This is an involuntary attempt to restore balance, but it instead shifts the body’s center of gravity increasingly farther from center. It is very difficult for the person with Parkinson’s to stop moving when festination occurs, and often he or she falls. Festination often begins when the person is attempting to change direction or to stop; it is a combination of gait disturbances and postural instability. walking aids such as a walker, walking stick, or cane can help to prevent festination.
People with Parkinson’s often drag one foot or sometimes both feet, depending on whether movement dysfunctions are unilateral (primarily affect one side) or bilateral (affect both sides). Foot drag involves both motor and proprioception dysfunctions. The dopamine depletion that characterizes Parkinson’s disease causes distortion in the movement signals from the brain to muscles that results in bradykinEsia and incomplete motions. As well, the body’s sense of orientation and placement becomes distorted as sensory signals from the muscles to the brain also encounter disruption. Foot drag raises the risk of injury because it increases the likelihood of stumbling and falling. The person with Parkinson’s can help overcome mild to moderate foot drag by consciously concentrating on lifting each foot completely from the surface with every step. This effort also improves shuffling, another gait disturbance common in Parkinson’s.
Freezing of Gait
Freezing when walking or attempting to walk, in which the person with Parkinson’s temporarily cannot move, is one of the most frustrating and common gait disturbances of Parkinson’s disease. Freezing of gait (FOG) is sometimes called “magnetic feet” as the person with Parkinson’s feels that his or her feet are stuck in place. Other terms for FOG include gait hesitation and stop hesitation. It is most likely to occur when there is a change in the walking surface, such as going from a carpeted room to a tiled floor or approaching stairs, and at the point of the change, such as a threshold. This tendency suggests that there is a visual component of FOG.
Although FOG occurs because of the disruption of nerve signals from the basal ganglia and other structures in the brain that direct movement, scientists do not fully understand the mechanisms of how it takes place. FOG likely represents dysfunctions of the motor-sensory feedback loop, in which signals back to the brain from the muscles are distorted as well. Some people with Parkinson’s experience FOG during off-state episodes, and others experience FOG regardless of their medication cycles. Anxiety about walking can increase the frequency of freezing episodes. The duration of a freeze varies from a few seconds to as long as several minutes.
People with Parkinson’s deal with FOG in various ways, from waiting it out to concentrating on the intended movement to thinking about something entirely different. One of the most effective techniques for many people is to anticipate points at which FOG is likely, such as surface transitions, and approach them as though they are tangible obstacles that must be stepped over. Consciously raising the foot in a high step and “reaching” it over the imagined obstacle then seem to circumvent the freeze. Marching or thinking about dancing to a rhythmic beat are also techniques to break out of a freezing episode. Changes in the environment, including removing carpet or rugs in favor of tile or hardwood floors, and removing clutter around the home to make rooms seem more open are often effective in reducing freezing as well.
Retropulsion is the tendency to step back; pulsion (sometimes called antepulsion) is the tendency to step forward when bumped or bumping into an object. A person with normal gait may take a step or two; a person with Parkinson’s takes an uncontrolled number of steps. This is a function of impairments to balance and motor skills (muscle control). Retropulsion or pulsion can also occur at points of transition during movement, such as initiating walking, changing direction, and stopping. Retropulsion and pulsion events often end with falls as the person loses control of movement. Walking aids reduce the risk for these gait disturbances.
Walking stooped forward with short, shuffling steps is perhaps the most distinctive gait disturbance of Parkinson’s. In this gait, the person’s feet barely clear the surface when walking, or one or both feet may drag. Heel and toe typically overlap, sometimes to the extent that the feet barely clear each other and forward progress is very slow. There is minimal to no arm swing. This shuffling gait is a combination of postural instability, rigidity (increased muscle tone), and impaired movement. In the early and mid stages of Parkinson’s disease, anti-Parkinson’s medications typically eliminate this gait disturbance and the person appears to walk almost normally. The difference can be striking, and apparent within 20 to 30 minutes of a levodopa dose.
Start and Stop Hesitation
Start and stop hesitations are manifestations of freezing of gait that occur at the beginning or end of walking. In start hesitation, the person with Parkinson’s is in position to walk but cannot initiate movement. Stop hesitation occurs when the person is walking and suddenly stops, or freezes. Start hesitation is common during change of direction when walking, if the person stops before turning. The same approaches for overcoming FOG are often effective for start and stop hesitation. Most important is patience, both to the person with Parkinson’s and to others.
Techniques for Accommodating or Overcoming Gait Disturbances
Even though walking appears to be a conscious act and concentration can overcome some of the challenges people with Parkinson’s face, the gait disturbances that characterize Parkinson’s disease are involuntary. Physical therapy and occupational therapy can teach methods for overcoming or compensating for gait disturbances. Remaining as physically active as possible helps to maintain independent mobility for as long as possible.
People with Parkinson’s who have pronounced gait disturbances often are uncomfortable in public, afraid that they may fall and worried that others will not understand that their mobility problems are beyond their ability to control. People with Parkinson’s-related gait disturbances who can view their situations with humor find it easier to deal with the challenges. Maintaining a positive outlook allows the person with Parkinson’s to explore creative, even if unusual, solutions to common but frustrating gait problems such as start hesitation and freezing. Some people scold or cajole their feet, for example, as though they are recalcitrant children, or sing or recite favorite poems during FOG episodes. This method helps to relieve anxiety for the person with Parkinson’s as well as for others present. As the person with Parkinson’s knows all too well, directing frustration at the situation only prolongs and intensifies it.
When gait disturbances occur in early or mid-stage Parkinson’s, adjusting the anti-parkinson’s medications regimen often corrects them. This may mean changing doses or dosage times or trying different drugs or different combinations. In later stages of the disease when anti-Parkinson’s medications are losing their effectiveness, such adjustments are less likely to often do help. For some people, especially those with early-onset Parkinson’s who are younger and have few or no other health disorders, surgery such as deep brain stimulation (DBS) or pallidotomy becomes a viable option and can improve not only gait but other motor Parkinson’s symptoms such as tremors. Because motor system deterioration continues as the Parkinson’s progresses, however, these approaches do not produce permanent relief.