Effect of calcitonin on bone mineral density and biomechanics around the artificial prosthesis in the rabbit of diabetic osteoporosis model / 中国医师杂志

ABSTRACT

Objective To investigate the influence of calcitonin on bone mineral density and biomechanics around the artificial pros-thesis in ovariectomized diabetic rabbit model. Methods Fourteen femina New Zealand white rabbits at the age of 5 months old were select-ed, which weight 2.24 -2.65kg, averaging 2.26kg. First, the model of rabbit with diabetic osteoporosis was successfully established by the compound method of ovariectomy plus streptozotocin. Osteotomy in the middle part of femur was performed in both groups, fixation of artifi-cial prosthesis was done with 3.0 kirschner wire. After that, Rabbit models with diabetic osteoporosis were randomly divided into experimen-tal group and control group. Rabbits in the experimental group were treated with calcitonin 6U intramuscular injection once every other day. In control group, intramuscular injection of normal saline solution 1.5ml once every three days. Rabbit models of two groups were sacrificed in the 24th week. The BMD of the region of interest (ROI) around the prosthesis were detected before experiment and 8, 16 and 24 weeks after injection. After rabbits were killed, experimental femurs in both groups were complete removal and soft tissues were rejected. Determi-nation of the pull-out and torsion bone biomechanics experiments of prosthesis was done in both groups respectively. Results The BMD of ROI in the experimental group before operation was (0.1863±0.004)g/cm2 and (0.1753±0.005)g/cm2 in 24 weeks after operation, in control group before operation was (0.1865±0.002)g/cm2 and (0.1638±0.005)g/cm2 in 24 weeks after operation. There were significant difference between the two groups(P < 0.05). Biomechanical show that the pull-out strength in the experimental group was (312.68±8.73 )N/cm2 and (205.43±12.45 ) N/cm2 in control group. There were significant difference between the two groups(P < 0.05). The tor-sion strength in experimental group was (80.47±2.51) N/cm2 and (38.52±0.64) N/cm2 in control group. There were significant differ-ence between the two groups(P < 0.05). Conclusion Salmon calcitonin can reduce the bone turnover rate around prosthesis and decrease bone absorption in the rabbit of diabetic osteoporosis models, accelerate the bone formation around prosthesis, and increase the BMD. It can ameliorate the quality of bone around prosthesis, improve its biomechanics property, and increase the holding power between prosthesis and body mass. It is of clinical significance for the prevention and treatment of aseptic loosening artificial prosthesis.