HealthCentral: When Weakness in Your Left Arm Means Stroke

HealthCentral recently interviewed neurologist Benedict Pereira, MD, a stroke specialist at Cedars-Sinai, about how to tell whether sudden arm weakness is a sign of stroke or another condition.

A stroke occurs when blood flow to the brain is blocked or interrupted, preventing brain cells from getting oxygen and causing them to become damaged or die. Symptoms can include sudden weakness or heaviness in one arm, typically on the side opposite the affected area of the brain.

While arm weakness may accompany other symptoms like facial drooping, speech difficulties or vision changes, Pereira told HealthCentral that sometimes “arm weakness can be the only sign of stroke.”

He said the key difference between stroke-related arm weakness and other causes is speed.

“What makes a case more likely to be a stroke, as opposed to other causes, is its sudden onset,” Pereira told HealthCentral. “A stroke doesn’t gradually start happening—it happens instantly.”

Other conditions can cause arm weakness that develops over time. These include pinched nerves, peripheral neuropathy and brachial plexus injury—damage to the nerves running from the spine into the arms. Additional causes include autoimmune diseases, such as Guillain-Barré syndrome, in which the body’s immune system mistakenly attacks the peripheral nerves outside the brain and spinal cord.

Pereira told HealthCentral that Guillain-Barré syndrome typically causes weakness on both sides of the body, starting in the feet and arms.

“Chances are you would know you have it before it reached your arms,” he said.

Pereira emphasized that time is critical during a stroke, because the most effective treatment for reducing brain damage must be administered within four and a half hours of symptom onset.

Experts encourage the use of the F.A.S.T. acronym to remember the warning signs of a stroke: facial drooping, arm weakness, speech difficulties, and time to call 911.

Read the complete article from HealthCentral.