John Kerry (search) plans to have minor surgery Wednesday to repair a shoulder that he injured on the campaign trail.

Kerry's spokesman David Wade said the Massachusetts senator tore the subscapularis (search), a muscle beneath the scapula (search) in his right shoulder, when he braced himself during an abrupt stop on his Iowa campaign bus several weeks ago.

After the surgery, Kerry will use a sling for roughly a week, said campaign spokeswoman Stephanie Cutter. She said Kerry will return to work Thursday for administrative business and resume a public schedule next Sunday.

Wade said the Massachusetts senator's shoulder didn't bother him when he was skiing and snowboarding last week during an Idaho vacation. Kerry felt pain when he picked up a baby while greeting voters recently, Wade said.

Wade said the surgery would be an hour-long outpatient procedure at Massachusetts General Hospital in Boston, and he will likely undergo general anesthesia. He said Kerry made the appointment Saturday after reaching his doctor, Dr. Bertram Zarins, who was on vacation in the Virgin Islands.

Wade said Kerry was having the surgery "for convenience, just to get it done."

"He decided it was better just to get it fixed now," Wade said. "He decided to pull the trigger."

Kerry interrupted his campaign schedule for surgery twice last year. He had a cancerous prostate removed in February 2003 and minor outpatient surgery to remove a wart on his eyelid the following month.