Elbow pain can result from flexing the elbows for too long, such as while talking on a cellphone or leaning on a window frame while driving. (Kevork Djansezian/Associated Press)

As people spend more time gabbing on cellphones, doctors in the U.S. say they are seeing more cases of numbness, tingling and pain from "cellphone elbow."

Cubital tunnel syndrome is similar to carpal tunnel syndrome that causes pain in the hand and wrist, but in this case it's the ulnar nerve that crosses the inside of the elbow that gets pinched.

"Cellular telephone use has increased exponentially, with 3.3 billion service contracts active worldwide — or about one for every two people on the planet," Dr. Peter Evans, director of the Cleveland Clinic's Hand and Upper Extremity Center, and his colleagues wrote in the May issue of the Cleveland Clinic Journal of Medicine.

"The exact incidence of cellphone elbow is not known, but anecdotal reports and our own clinical experience indicate that its incidence parallels the rise in the use of cellphones and computer workstations."

The repetitive strain injury is caused by prolonged flexing of the elbow, including from:

• Pulling, reaching or lifting.
• Constantly leaning on the elbow to talk on the phone, or resting an elbow on a window frame during a long drive, or on wheelchairs.
• Typing for hours with arms bent at a 90-degree angle.
• Keeping the elbow bent at night while sleeping.
• Sustaining an injury to the elbow area.

Patients with cubital tunnel syndrome often notice numbness inside the hand in the ring and little finger but symptoms vary between people.

"It's quite interesting, actually," said Jennifer Howey, a physiotherapist in Toronto. "Today, with technology, we have cellphone elbow but we commonly also see Blackberry thumbs and now Wii shoulders."

When the ulnar nerve is stretched and tensed for a long time, it will become irritated and not perform well.

Physiotherapy and acupuncture can settle the inflammation, and shaking and pumping the arm can also help, Howey suggested.

Phone tips

If the nerve compression persists, symptoms may worsen to hand fatigue and weakness, including difficulty opening bottles or jars, Evans's team said.

In most cases, lifestyle changes can help prevent or resolve symptoms, the researchers added. These include:

• Using a hands-free headset.
• Switching hands while on the phone.
• Using an elbow pad to keep the arm straight at night.

In severe cases, the pinkie and ring finger can curl up.

To diagnose the syndrome, doctors take a complete medical history and physical exam, and they may order tests of nerve conduction and muscle function.

Stopping the activity that is causing the problem is the most effective treatment, according to the University of Virginia Health System's web page on the topic.

Other treatment options include reducing or ceasing activities that aggravate the condition, anti-inflammatory medications and surgery.