Bone fractures, especially when treated surgically, are connected with changes in thehomeostasis of the elements of which bone compounds consist, as well as the ones whichparticipate in controlling processes. Such changes influence both the fracture itself andthe operative procedure. For successful treatment of broken bones, it can be crucial to bringthe homeostasis of bioelements back to the normal state.Thus, the aim of this work has been to determine magnesium and calcium concentrationsin plasma from patients with fractures of long bones, and to analyze changes in the examined elements depending on the time after the operative procedure, injury and patient’sage.The research was conducted on the blood of patients: 1) with long bone fracturestreated surgically, 2) after a limb amputation because of a fracture or injury, 3) with longbone fractures and with multiorgan injury. With respect to the patients’ age, there were 3 groups: 1) patients aged 18-40 years, 2) patients aged 41-60 years, 3) patients older than 60 years. In the postoperative period, the patients were on a strict postoperative diet, receivingonly i.v. 0.9% NaCl and 5% glucose solutions.Blood was taken from patients first directly after admittance to hospital and nexton the first, third, fifth and seventh day after an operative procedure.Plasma calcium and magnesium concentrations were determined by the method of emissionspectrometry with induction plasma (ICP-OES). The results were worked out statistically.The differences p