Grammy Award-winner Sam Smith has undergone successful vocal cord surgery at a Boston hospital.

Massachusetts General Hospital said in a statement today - the singer's 23rd birthday - that he is expected to make a full recovery.

The surgery to stop recurrent vocal cord bleeding was performed by Dr Steven Zeitels, who has performed the same procedure on Steven Tyler, Lionel Richie and Adele.

Smith's song Stay With Me won Grammys for song and record of the year and he was also named best new artist in February. The British's singer's In The Lonely Hour was named best pop vocal album.

According to the hospital, Smith's condition was the result of unstable blood vessels in the vocal cord that can rupture and prevent vocal performance.

Smith's next live show is scheduled for July 18.