Richard Greens threw his victim down concrete stairs, leaving him screaming in agony after his shin bone was left sticking out through his skin.
Edinburgh Sheriff Court heard that the 35-year-old had erupted after hearing someone at the party calling him “Robert”.
His wife Lee, 32, whom the court heard had “waggled” the victim’s shattered shin bone following the brutal attack, was given the chance to undergo a drug testing treatment order (DTTO) instead of jail.
Richard Greens’ defence solicitor Murray Robertson told the court yesterday that his client had been “under pressure” ever since the release of his brother in January, which sparked a public outcry when he was moved to Midlothian.
Robert Greens was jailed in 2005 after raping a Dutch student near Rosslyn Chapel.
Mr Robertson said: “It is not the first time in Penicuik he has had to take abuse as a result of being mistaken for his brother. To some extent he has been dogged by this.”
He added that the twins were identical except for a mark on his client’s neck.
At an earlier hearing, father-of-five Greens admitted assaulting Garry Campbell.
The court heard that Greens and his wife, Lee, 32, both of Woodside Drive, Penicuik, had gone to a New Year’s party at a relative’s home. They had been drinking heavily and Richard Greens had been taking Valium.
Another individual at the party – not Mr Campbell – accidentally called him “Robert” and he refused to accept it was a mistake.
After arguing furiously with party-goers, Greens threw Mr Campbell down the stairs.
Lee Greens then kicked the man’s broken leg, accusing him of being a “drama queen” before she “waggled” the broken limb three or four times as Mr Campbell screamed in pain.
Mr Campbell was taken to Edinburgh Royal Infirmary for treatment. The court previously heard that Mr Campbell was expected to have “considerable” scarring on his leg.
The couple also admitted a charge of reset – the Greens were arrested at their home, where police discovered items that had been stolen during a housebreaking.
Sentencing Richard Greens yesterday, Sheriff William Holligan rejected a plea to spare him jail pending further reports about drug treatment.
He told Greens that if he had not admitted the serious assault in the house in Carlops Road, Penicuik, the sentence would have been 16 months.
Yesterday’s sentencing had been delayed because the Greens failed to keep a previous court date – claiming they were stuck in traffic.
Speaking to the Evening News last month as he backed the campaign to evict his brother from Midlothian, Richard Greens said: “The hassle I have had is unbelievable, I’ve even had bairns run away from me in the street.”