The Boston hospital that last year performed the country’s first face transplant now plans to offer hand transplants under an experimental program announced. Brigham and Women’s Hospital has screened at least half a dozen people who have lost one or both hands and may be eligible for the complex surgery, Matthew Carty, MD, a reconstructive plastic surgeon, said in an interview. “We’re extremely excited about being able to offer this to patients,’’ he said. “There’s a huge potential pool of candidates in our soldiers returning from the front lines who have had severe limb injuries.’’ Fewer than 50 hand transplants have been performed worldwide, and only three US hospitals, in Louisville, KY, Pittsburgh, and at an Air Force base in Texas, have undertaken the procedure. UCLA Health System launched a program last month. Face and hand transplants are considered more complex than transplants of organs such as livers or kidneys because surgeons must also fuse bones, tendons, muscles, ligaments, nerves, and blood vessels, requiring delicate microsurgery.