Boy W, who cannot be named for legal reasons, was left 'utterly shattered' by the incident, said his father.
But no disciplinary action was taken against the boy, also aged 10, who broke W's arm last November while giving him a 'Chinese burn.'
Instead, he said, his son was the one punished by being unfairly isolated from other children at the school in Basingstoke, Hants.
'I also want to protect the future safety of all children at the school, including my son.'
Mr W was speaking after being given leave to apply on his son's behalf for judicial review of the head teacher's decision not to take disciplinary action against the assailant.
He is also challenging the school governors' decision to take no action, while imposing conditions on W.
Mr W says the conditions were ostensibly to protect W from further injury while his arm mended, but they had the effect of denying him the company of friends and isolated him from communal school activities.
Mr Justice Forbes ruing it was an 'appropriate case' to grant leave after Philip Engelman, representing the family in court, said letters from the head and the chairman of governors demonstrated the school had 'closed its mind to this serious matter and the bullying that underlies it.
'There has not been a serious investigation of the underlying facts, or serious consideration of the harm actually inflicted on the applicant by the other boy,' said counsel.
The head teacher had been reluctant to take action and indicated very shortly after the incident that he believed there was no serious assault.
W was waiting in a lunch queue when the incident occurred and he suffered a spiral fracture to his arm, which indicated that considerable force was used in the assault.
His assailant had admitted: 'I went and gave him a Chinese burn and he moved, then I heard it click.'
W had previously been bullied to such an extent in the lunchtime queue by the same boy that he had decided to stop having school dinners and had only resumed so that he could be with his friends.
The police concluded that W's assailant may have been guilty of criminal assault but the boy's parents, on legal advice, had refused to accept a formal caution. There was to be no prosecution.
In January, the governors decided no action would be taken against W's assailant over the 'accident', and said they were satisfied with the school's anti-bullying policy.
Later the local education authority wrot to Mr W pointing out that a police investigation had not established 'evidence of intent' to cause harm and it was proposed to take no further action.
Since W's return to school in January, 'a policy of isolation' had been applied, denying him the opportunity to be accompanied by a friend at lunchtime, nor permitting him to take part in activities outside the classroom, other than PE and games for which he was not fit.
The chairman of the governors had also written to the father saying they would not tolerate 'a campaign against the good name' of the school and its headteacher.
Outside court, Mr W said: 'This was serious bullying which required serious action.
'My son is utterly shattered by what has happened. It is outrageous.
'On the one hand, he has discovered the truth of British justice. A 10-year-old juvenile can do anything and doesn't get prosecuted and his parents are allowed to refuse a caution, at which point an informal warning is given.
'He is shattered by that and the fact the school appear not to care. Now he is isolated. He, the victim, is being punished.'