A man was walking towards the main bar in NB’s bar in Bridge Street, Northampton, when he was attacked.
The victim was hit by an unknown man with dark hair who punched him in the face and neck.
He fell and broke his hip.
The assault at around 2am on Sunday (October 30) at around 2am.
Anyone with information can contact Northamptonshire Police on 101 or Crimestoppers anonymously on 0800 555111.