Most Parkinson's patients suffer from freezing, but causes for this symptom is not clear. Photo: Frank Rumpenhorst/dpa
A common symptom of Parkinson’s disease (PD) is ”freezing,” a temporary inability to move.
”Patients describe it as feeling like their feet are ‘glued’ to the ground,” says neurologist Dr Andres Ceballos-Baumann, chief physician in the Parkinson’s clinic at Schön Hospital in Munich-Schwabing. “It affects almost all patients during the course of the disease.”
There are various forms of PD, a progressive nervous system disorder for which there’s no cure. Roughly three in four patients have idiopathic Parkinson’s, meaning the cause is unknown.
The disease causes neurons in a part of the brain called the substantia nigra to gradually break down or die, explains the German Parkinson Association (DPG). These brain cells produce the chemical messenger dopamine, which among other things plays a key role in generating movement.
Decreased dopamine levels lead to symptoms including tremor, stiff arms and legs, slowed movement, balance problems - and freezing.
Freezing often develops gradually. “If it occurs right at the beginning of the disease, there’s good reason to doubt that it’s the typical form of PD and not another form,” says Ceballos-Baumann.
Whether and exactly when freezing episodes occur depends in part on the medications - the primary means of treatment - that are prescribed to help control PD symptoms, he says. Many of them increase or substitute for dopamine.
Their effectiveness fluctuates. During “off” periods when medication isn’t working well or the patient is due for the next dose, PD symptoms aren’t controlled as well. “And during these off periods, freezing can be more frequent or severe,” Ceballos-Baumann notes.
Special training can protect Parkinson's patients from freezing up, something that not only restricts mobility and independence, but also increases the risk of injury. Photo: Frank Rumpenhorst/dpa
Freezing often occurs when people with PD start to move, transitioning from standing to walking. “The traffic lights turn green but they can’t budge” - a state that may last a few seconds or as long as half a minute, he says, “by which time the lights may have turned red again.”
Time pressure can also trigger a freezing episode: The telephone in the hallway rings or the person thinks about having to get out of the bus at the next stop.
Walking through doorways is another action that can lead to freezing. ”The automatic door at the supermarket can present a problem, for example,” Ceballos-Baumann says. Many PD sufferers are therefore hesitant to leave their home for fear of freezing in public.
Turning around can be tricky too, for instance when the person is in the kitchen and wants to take something out of the refrigerator. ”Their torso turns but their feet remain rooted to the spot.”
If they lose their balance and fall, the consequences can be serious. They often land on their hip, which can result in complicated fractures.
Freezing engenders strong feelings of helplessness. The good news is that compensation strategies can help. But what works for one person may not work for another. “It all has to be rehearsed individually and constantly repeated,” Ceballos-Baumann says.
It’s best to begin with the strategies as soon as possible, and cues are the key. They’re external stimuli that prompt forward movement and help to break - or even prevent - a freezing episode.
”You can gently rock back in forth and place, using the rocking to initiate the next step,” advises Ceballos-Baumann. Or you can lightly slap your thigh to signal your foot to leave the ground. An auditory cue would be to listen to the ticking of a clock - using it as a metronome - or to count to yourself.
The traffic light changes to green, you want to start walking, but your feet remain glued to the ground. This is an example of freezing - something that occurs in Parkinson's disease. Photo: Mascha Brichta/dpa
A visual cue would be to paint or tape lines on the floor of your home to prompt you to step over them. Many PD sufferers can climb stairs with no difficulty, notes Ceballos-Baumann, because “stairs are like lines on the floor.”
There are also special aids for PD patients, for example walking sticks with a lever on the handle that makes “a small horizontal bar pop out at ground level that the patient can step over.” Walkers that, at the push of a button, project a laser line across the ground are available as well. Or as a less expensive alternative, Ceballos-Baumann suggests “stretching a clearly visible cord between the walker’s rear wheels, and hanging a small ball on it that you can kick.”
PD sufferers need to keep in mind that cues can become less effective over time. “When patients always hear one rhythm - the ticking of a clock - then after a while they don’t notice it any more,” he says. ”That’s the problem.”
If a friend or family member witnesses a freezing episode, they should show understanding. “It’s not easy for people who don’t have PD to comprehend how someone can go up and down stairs smoothly but come to an abrupt halt in front of a doorway,” says Ceballos-Baumann.
They can also help by reminding the PD sufferer of the cues he or she has learned. Or they can serve as a metronome themselves by counting aloud: “one, two, one, two, one, two ...” Something else they can do is to place their foot perpendicular to the “frozen” person’s foot and ask them to step over it.
It’s also important that they’re mindful of whether freezing episodes become more frequent. If so, points out Ceballos-Baumann, it could be a sign that the timing and/or dosage of the person’s medications need to be adjusted, or that the person isn’t taking them regularly. – dpa
