He broke someone’s arm and that man lost his job; what must he do?
Question

Two neighbours had an argument because of a fight between their children. After they stopped the fight and separated the children, and each of them went to his own house, one of them came back out into the street, and started to impugn the honour of the other. When his neighbour heard him, he attacked him and beat him up, and broke his arm. The one whose arm was broken lost his job, so what are the rights and duties of each of them? What does Islam say about such a situation? Please note that both parties want to put an end to this problem and resolve the matter in a fair way. What is the Islamic ruling on that?
Praise be to Allah.Issues of disputes should be referred to the courts, but we can advise you that if the arm is paralyzed, then half of the prescribed diyah [for killing a person; diyah or “blood money” is compensation that must be paid for killing or injuring a person] must be paid for it. If it is put in a cast or loses its strength, then compensation must be paid.
Ibn Qudaamah (may Allah have mercy on him) said: If someone attacks another person’s arm and it becomes paralyzed, then the prescribed diyah [“blood money” or compensation] must be paid, because use of it has been lost. So he must pay the diyah for that, as is also the case if he caused his eye to go blind without removing the eye, or he makes him unable to speak, or he damaged its arm and made it crooked, or caused it to lose its strength or disfigured it; in those cases he must pay a discretionary compensation for the damage caused.
If he broke his arm, then it was put in a cast and straightened, he must pay discretionary compensation for disfiguring it. If it became crooked, then the discretionary compensation is greater, because the disfigurement was greater. End quote from al-Mughni (8/458).
The diyah for an arm is fifty camels.
With regard to injuries for which no specific diyah is prescribed, the judge may work out what they should be.
See: al-Mawsoo‘ah al-Fiqhiyyah (18/68).                                      
If the injured party needs treatment, the one who caused the injury must pay for it.
Ibn Hazm (may Allah have mercy on him) narrated in al-Muhalla (11/89) from Shurayh that with regard to a broken limb, if it need to be set in a cast, he ruled that that makes the liability greater, because the one who caused the injury must pay the doctor’s fee, as well as the injured party’s lost earnings from his work.
In ad-Durr al-Mukhtaar (p. 707) it says: In Jawaahir al-Fataawa it says: If a man injures another man, and the one who is injured becomes unable to earn a living as a result, then the one who caused the injury must pay for his maintenance and medical treatment. End quote.
Dr. Haani al-Jubayr said: Some of the fuqaha’ said that the one who caused the injury is liable for the injured party’s loss of work. In the case of a broken bone, if it is set in a cast, Shurayh ruled that the one who caused the injury must pay the doctor’s fee, as well as the injured party’s lost earnings from his work.
The scholars differed as to whether that is limited to the basic maintenance he needs, or whether it should be connected to the earnings that he missed out on because of being out of work.
This view makes sense, because it is a basic principle of Islamic teaching that harm should be removed, then it is up to the judge to decide to what extent the offender is liable.
End quote from http://bit.ly/2lBU9gY
With regard to the one who started the insults, he must repent, and the qaadi (judge) may impose a discretionary punishment, such as flogging or imprisonment, but he does not have to pay any financial penalty, regardless of whether the one whom he insulted pardons him or not.
And Allah knows best.