Could trace elements be linked to fracture healing acceleration in TBI-related skeletal multitrauma?

Dealing with trauma cases, physicians may have noticed that patients with concomitant TBI has shorter terms in bone callus formation. Such phenomenon was firstly reviewed by Morley back in 2005. Identification of the most significant factors affecting the acceleration of bone union may give opportunities for nonunion treatment. Materials and methods. To reproduce the isolated fracture and TBI-related polytrauma, 90 white female rats were used. According to the timing of the samples harvest(7, 14, 21 days), the animals were divided into six equal subgroups. Hip fracture was modeled by blunt guillotine injury, while for TBI modified control cortical impact was used. Results. At day 14 the concentration of both blood and bone copper increased in the polytrauma animals(p = 0.002) and in the sham(p = 0.004). There was a spike of 43% in the average blood copper in sham group on day 21. Meanwhile, bone copper decreased by 17%(p = 0.013). The difference in bone zinc concentration on day 21 was 25% in favor of the sham group (p < 0.001), while blood zinc at 21 days was amounted to 39% in favor of the polytrauma rats. On the 14th day the average concentration of blood magnesium reached equal concentrations for both groups (p = 0.47). At the time of day 21, bone magnesium of both groups was almost the same in favor of the multitrauma (p = 0.2). At the time of 14 days, the bone calcium of polytrauma animals increased by 1.4 times (p < 0.001). After reaching this peak on day 14, the calcium returned to a value equal to sham group one week later(p = 0.12). Conclusions. The critical period of acceleration could be day 14, which corresponds to the peak values of bone zinc, magnesium, and calcium. The third week was accompanied by a decrease in the bone trace elements with a simultaneous increase in the concentration of blood cadmium.