Miley Cyrus underwent an operation on her wrist on Friday (12Dec14).

The Wrecking Ball hitmaker posted a graphic image on Instagram.com of what appears to be her wrist mid-operation, showing a flesh wound being prised open with metal tools.

She did not explain the nature of the surgery, but a source tells E! News that she had a cyst removed and is "doing fine".

A source also told People.com, "She had an outpatient procedure on her wrist..."

Cyrus uploaded more snaps from her hospital visit, showing her lying on a bed with her wrist in a black cast, and another 'selfie' of her in a surgical gown.