COMPARATIVE CHARACTERISTICS OF THE BONE MARROW FROM FEMORAL HEAD AND ILIAC BONE IN PATIENTS WITH FEMORAL NECK FRACTURES
Increasing number of elderly patients with femoral neck fractures requires a search for an optimal treatment regimen based on a natural sustenance and regulation mechanisms of bone homeostasis. Purpose of the study - to perform a comparative cellularity analysis of bone marrow obtained from femoral neck and iliac bone of elderly patients. Material and methods. The experimental group included 29 patients with closed fractures of femoral neck, injured by falling on the side from a standing position. Bone marrow was obtained from femoral neck and iliac bone during procedure of screw internal fixation or hip replacement. In the control group, the authors used bone marrow harvested from the same anatomical areas of 10 cadaveric donors. Nucleated cells (Ncs), hematopoietic stem cells (HScs) and multipotent mesenchymal stem cells (MScs) were counted in bone marrow by flow cytometry. Results. comparative study demonstrated that bone marrow from the hip of patients with fractures and cadaveric donors contained less concentration of Ncs and HScs than bone marrow from the ilium. However, the difference in concentration was significant only in the experimental group. at the same time, in patients with fractures the Ncs concentration and absolute content of HScs in bone marrow obtained from hip was significantly lower than those from cadaveric donors. Meanwhile, samples obtained from the iliac bone in the experimental and control groups had no significant difference. The authors also observed that concentration of HScs and MScs in the bone marrow from male hips was significantly lower than in females. as a result, male patients with fractures demonstrated difference in concentrations of HScs samples from ilium and femoral neck reaching 84.6%, MScs - 86.6%; females demonstrated differences of 68.9% and 69.2% respectively. Discussion. The data collected allows suggesting that one of the main factor violating micro-architecture of bone and in development of osteoporosis is an alteration in the cellular composition of bone marrow. while MScs are active in regeneration of bone tissue, increase in their concentration in the fracture zone can stimulate the healing. Thus, to improve treatment outcomes in patients with hip fractures after internal fixation with cannulated screws, it could be beneficial to use grafting of autologous bone marrow obtained from the iliac bone featured by a higher stem cells concentration.