The victim, aged 18, was grabbed, taken to a back garden, handcuffed, his mouth taped and then beaten by at least seven men. It was one of Northern Ireland's worst punishment attacks, police said.
Chief Superintendent Ian Williamson of the RUC said: "It bears all the hallmarks of Sinn Fein-IRA thuggery. It was outrageous."
The youth, who has not been named, was seized and taken to the back garden of a house in Norglen Road, Andersonstown.
There he was bound with plastic handcuffs and black tape before spikes were hammered into his elbows and kneecaps.
Last night he was in the City Hospital suffering from a broken left elbow and leg and various puncture wounds.
This was the 3Oth paramilitary punishment attack in that part of west Belfast in the last year. There have been more than 210 others throughout Northern Ireland. Loyalists have been responsible for up to 100.
But this latest attack was blamed on republicans. Chief Supt Williamson urged witnesses not to be intimidated from coming forward.Reuse content