For Mary Spencer, just standing up straight can be a challenge. Multiple sclerosis has left her muscles prone to wild movements.
"You can't tell what direction is what. You're body doesn't know what's up or down," said Spencer.
But she says her ability to move normally has improved dramatically over the last few years. Not from taking medication, but simply putting on a vest.
"This is the Balance Wear assessment vest and it's Velcro receivable on the outside," said Oakland physical therapist Cynthia Gibson-Horn.
The vest, called Balance Wear, is Gibson-Horn's creation. She says it is designed to compensate for involuntary movement and loss of balance using a system of counter weights. Velcro panels inside allow therapists to move the cube shaped weights around as they test the effect on patients.
"If the patient has a balance problem, and I can identify the directional losses of balance, then we can treat those by strategically placing those light weights in the balance vest and right away you'll know that same treatment, whether or not your patient is going to benefit," said Gibson-Horn.
To see the effect, we asked Spencer to walk down a flight of steps without the vest. Her upper body is noticeably swaying, as she struggles to keep her balance.
Next Gibson-Horn places several weights in the vest, near her shoulder and lower back. Back on the steps, Spencer's gate is noticeably smoother and, she says, more controlled.
"At first I thought it was too heavy, especially when she added more weights, but it's not. It feels good. It's like I'm stabilized," said Spencer.
"If you think about balance, it's the foundation of movement. So you couldn't even sit, unless you had balance," said Gibson-Horn.
Gibson-Horn says more than 400 patients have been fitted with the vest. Research teams at two universities have now received a grant from the National Institutes of Health to study the devices long-term effectiveness. For Spencer, the results have already been life changing.
"I have the freedom to move without thinking, 'Where do I need to be? How do I need to stand?'" said Spencer.
The vest system comes in two models ranging from about $800-950. The more expensive version is covered by MediCare, but the other one is not.