Sean Meli, 34, threw punches at his mother and kicked her head three times with "great force" then left her on the floor with blood coming from her mouth and scalp.
Newcastle Crown Court heard the victim, who did not co-operate with the prosecution of her son, was unconscious after the violence, lost a tooth and had pain to her neck, back, abdomen and head.
The court heard the trouble flared in the early hours of February 8 last year when Meli stepped in to protect his girlfriend from an attack by his mother but went "far beyond what was reasonable".
A neighbour, who had been alerted by the noise, saw on a security camera what was happening in the lobby outside the victim's home.
Rachel Landen, prosecuting, told the court: "He is described as continually punching her to the face and head."
The court heard the violence continued despite worried neighbours calling for it to stop and saying that the police were on their way.
Miss Landen added: "The defendant was seen to kick his mother with what was described as great force, three times to her head."
A neighbour who witnessed the violence told police it lasted "approximately seven minutes"
Meli, of Victoria Road, South Shields, who has previous convictions for violence in the distant past, admitted assault.
Judge Robert Spragg told him: "You initially started by defending your partner, who herself was attacked, it would appear, by your mother and that is accepted by the prosecution
"But then you launched what can only be described as a sustained attack, including repeated punches and kicks, to the head with some force, that lasted seven minutes.
"It is no exaggeration to say you simply lost the plot."
Judge Spragg sentenced Meli to 21 months imprisonment, suspended for two years, with a three month curfew and rehabilitation requirements.
The judge said he accepted Meli's remorse for what he did and said the sentence could be suspended due to information contained in psychiatric and probation reports.
The court heard Meli has stayed out of trouble for years and is in a settled relationship with a young child and another baby on the way.
Meli told a psychiatrist he and his partner had turned up at his mother's home to borrow money when their funds ran low during a rare night out after the birth of their child.
He told the expert he was "acting in defence of his girlfriend" when the trouble started.