Long hours of smartphone use, especially in improper positions, can lead to significant musculoskeletal problems in the hands, fingers and wrists, according to Begüm Büyükerik, a physiotherapist and faculty member at Biruni University Vocational School.
In a statement from the university, Büyükerik said that although smartphones are designed for two-handed use, many people prefer one-handed operation for convenience.
“This habit places excessive strain on the thumb,” Büyükerik explained. “Using the phone with one hand creates a repetitive cycle of thumb movements. The rest of the hand also remains unnecessarily tense to grip the device. Over time, this can cause pain, reduced performance, and functional limitations.”
Büyükerik noted that one-handed phone use affects not only the thumb but also other fingers. She highlighted a growing deformity in the fifth finger, commonly known as the “pinky,” in recent years.
“This condition, referred to as ‘smartphone pinky,’ is becoming increasingly common,” she said. “Young people, in particular, constantly bend their pinky to support the bottom of the phone.”
The repetitive pressure on the small finger’s joints can lead to visible changes over time, including hollowing, slight bending, lateral shifting and indentation-like deformities on the bone. These changes typically result from soft tissues adapting to chronic pressure, Büyükerik explained.
Büyükerik emphasized that many shape changes in the fifth finger are largely preventable and offered the following advice:
Use the phone with both hands whenever possible.
Avoid using the pinky as a support.
Limit continuous phone usage and take regular breaks.
Incorporate simple hand and finger stretches throughout the day.
Use phone rings and ergonomic grips correctly to reduce strain.
“These precautions can significantly reduce the risk of long-term deformities, especially in young people,” she said.
She also warned that repetitive bending and straightening motions, poor posture, and prolonged static positions can reduce blood flow to the muscles, increase fatigue, and raise the risk of carpal tunnel syndrome.
While the long-term effects of smartphone use on hand muscles require further study, Büyükerik stressed the importance of developing proper habits early.
“Instilling healthy smartphone habits in youth can greatly reduce tendon, joint and nerve problems that may develop later in life,” she said.
