CHANGES IN FEMORAL BONE MINERAL DENSITY WITH ALLOGRAFT DURING REGENERATION DEPENDING ON BIOLOGICAL THERAPY AND RAT AGE

In orthopedic and trauma surgery, bone defects are an increasing clinical problem in daily practice. To fill them, many advantages have bone allografts (BA), namely a large stock of transplantation material. Purpose of the study: to evaluate changes in bone mineral density (BMD) of the femur of rats after filling a distal metaphyseal defect with an bone allograft in combination with the simultaneous administration of mesenchymal stromal cells (MSCs) or platelet-rich plasma (PRP) depending on age. Methods. The model of the hole defect in the metaphysis of the femur in rats (aged 3 and 12 months) investigated BMD in terms of filling BA, including, with the simultaneous administration of MSCs or PRP during surgery. Results. In rats with an unfilled defect — the immutability of BMD during the experiment. Compared with 3-month-old rats in 12-months-old rats with BA BMD was 1.11 times higher on the 14th day (p < 0.05), and on the 90th day it was 1.11 times lower (p < 0.05), on the 28th day it was not differed. In the 3-month-old rats with A and MSC showed a 1.20-fold lower BMD (p < 0.05) on the 28th day, and on the 90th day BMD did not differ compared to the group with BA. BMD in 12-monthold rats with BA and MSC did not differ from the group with BA. In in 12-month-old rats with BA and PRP BMD was 1.18 times (p < 0.05) higher on the 28th day and on the 90th day — 1.14 times (p < 0.05) compared to the BA group, and in 3-month-old rats did not differ for all terms. Conclusions. In the case of filling a bone defect with a bone alograft in 12-month-old rats, the increase of BMD of the femur is slower than in 3-month-old rats. The use of BA with MSCs in younger rats causes a delay in bone regeneration on the 28th day, but does not disrupt this process, according to BMD on 90th day compared to rats with BA, and in older rats does not significantly change BMD during the study. Filling defect BA with PRP promotes the growth of femoral BMD in older rats from the 28th d ay, b ut i n y ounger r ats it d oes n ot c ause significant changes compared to the group with BA.