Blackberry thumb refers to an injury or irritation of the tendons and muscles of the thumbs caused by repetitive movements when using cellphones, specifically BlackBerry phones, or other thumb-operated devices. This condition was named after the BlackBerry smartphone because of its popularity with business professionals and its wide use for texting and sending emails using its QWERTY keyboard. Unlike the other four fingers, the thumb does not have the dexterity to continuously perform high-speed tasks, making it sensitive to this type of injury.
Techopedia explains Blackberry Thumb
Blackberry thumb is categorized as a repetitive strain injury, which is caused by persistent, repetitive movements of a certain body part. Symptoms include a throbbing or aching pain at the base of the thumbs, which often persists even when the thumb is not being used. Sometimes, it radiates to the other fingers and wrist, causing disability of the whole hand.
Experts recommend a few basic precautions to avoid Blackberry thumb and other similar injuries:
Stop and rest. When using the device causes pain, stop doing whatever causes pain and rest. This will give the body a chance to heal, and reduce the risk that the injury will become a chronic problem.
Stretch and massage the area. Minimizing muscle tension in the affected area can resolve the aching sensation and improve flexibility.
Seek professional help. If the pain becomes unbearable and causes difficulty with daily tasks, consult a physician. Proper treatment and management of repetitive strain injury can reduce long-term consequences.
Blackberries aren't the only device to cause repetitive strain. In fact, there are terms for similar injuries acquired through a variety of gadgets, like "nintendinitis", "cellphone thumb", "wiiitis" and "PlayStation thumb".