NEW YORK -- Severe muscle spasms are a huge side effect of everything from spinal cord injuries and strokes to cerebral palsy and multiple sclerosis.

But doctors are now using some remarkable new technology -- implantable drug pumps -- to treat patients with muscle spasticity.

For some people, their muscle spasms are so severe, they limit their movement -- and their independence.

Kristina Hoover has multiple sclerosis, and her legs are cramped and stiff.

"My legs spasm all the time," she said.

Oral medication hasn't helped Hoover, who dreams of a day when she can bathe herself, feed herself and relax enough to sleep soundly.

Now, her dreams may come true. Dr. Eric Hassid, a Kaiser Permanente neurologist, is going to run a test to see if Hoover could benefit from a Baclofen drug pump.

It would be surgically implanted in Hoover's abdomen so it could pump tiny doses of medication through a tube straight into her spinal fluid 24 hours a day.

"Not only can it help with spasticity, but it can help with their motor control," Hassid said.

Hassid will run a spinal tap test to see if the delivery system will work for Hoover. First, he numbs the skin on her back, then he delivers a single dose of the drug by syringe straight into Hoover's spinal fluid. Then Hoover must wait several hours to see if the medication helps her.

Other patients rave about how well Baclofen works. Before therapy, Susan Lebowski's legs dragged on the ground, debilitated by muscle spasms.

Now, she says she "might be able to go out and dance again."

After the drugs took effect, Hoover said she still felt a little tight, but she was able to overcome the muscle spasms much easier. Hoover will get the pump with higher doses of the drug. Hassid said he can use a remote control to regulate and change the dose of the drug by computer.

Hoover will need to get her pump refilled in an outpatient procedure every two months.

Doctors can tailor the pump to function as the patient wishes, programming it to deliver high doses at night and low doses during the day for someone like Hoover. The pumps run on batteries that last from five to seven years.