Police in West Lothian are appealing for witnesses following the incident at around 11.45pm on Thursday 4 October in Livery Street near to Hanover Close.
The victim was approached by two men who assaulted him, leaving him with serious injuries to his pelvic area.
The suspects are believed to have left the area on foot towards Waverley Street.
The victim was treated at St John’s Hospital in Livingston and later released.
The first suspect is described as a white man, wearing a red jacket, khaki-green coloured shorts, white trainers and a multi-coloured hat.
The second suspect is described as a white man, wearing a long sleeved grey top, black jogging bottoms and black hat.
Detective Sergeant David Macmillan from Livingston CID said: “This was a brutal attack that left the victim requiring hospital treatment.
“I would ask anyone who was in the Livery Street area shortly before midnight last night and who witnessed what happened, to come forward.
“Equally anyone who may have any information that can assist with our ongoing inquiries and in tracing those involved, is asked to contact officers immediately.”
Those with information can contact Livingston CID via 101, quoting incident number 0192 of 5th October, or Crimestoppers anonymously on 0800 555 111.