ABSTRACT
Periprosthetic joint infection is the most serious complication after artificial joint arthroplasty. Epidemiological investigation has indicated that perioperative anemia is an independent risk factor for periprosthetic joint infection, which could play an important role by suppressing cellular mechanisms and autoimmune functions. Many domestic and overseas scholars have studied the relationship between periprosthetic joint infection and postoperative anemia, but the relationship between preoperative anemia and periprosthetic joint infection is relatively rare. However, preoperative anemia can reduce the C3b receptor on surface of red blood cells, decrease immune function of the body, increase blood-borne infection, prolong postoperative rehabilitation time, and lead to periprosthetic joint infection. For patients with preoperative anemia, prophylactic antibiotics could be used to prevent. And complement chalybeate used before operation, correct anemia by hemopoietin, treat chronic complications influence by hemoglobin production and improve patient's own immune status, blood transfusion treatment for patients with blood transfusion indications are performed. It could be better prevent occurrence of periprosthetic joint infection after total joint arthroplasty, and reducing chance of secondary or multiple renovations.
ABSTRACT
Objective By measuring the microstructure parameters of cancellous bone in vertebral bodies with different bone mineral density (BMD) levels, to study the correlation between such parameters and the corresponding maximum pullout strength (MPS) when fixed by pedicle screws, so as to understand if the microstructure parameters are related with screw stability and further to reveal the cause of screw loosening. Methods Based on the BMD detection results, fresh human cadaver spines were stratified into four levels: normal, osteopenia, osteoporosis and severe osteoporosis, according to diagnosis criteria in clinic. The corresponding vertebral specimens were then instrumented with pedicle screws, and screw pullout tests were conducted to measure the MPS of such screws. All the vertebral specimens were collected subsequently, and the cancellous bone cylinders were drilled from the center of each vertebra for micro CT scanning. Microstructure parameters of the vertebral trabecular bone at different BMD levels were obtained to investigate the interrelationships in between, and the relationships between the microstruture parameters and corresponding MPS of pedicle screws with osteoporosis severity were then compared. Results With the decline of BMD from normal to severe osteoporosis level, the corresponding MPS of pedicle screws was significantly declined. With the severity of osteoporosis increasing, the progressive bone volume loss, mechanical incompetence and microstructure deterioration also appeared evidently. Significant differences were found in microstructure parameters at different BMD levels. Strong correlations were extensively observed among BMD, microstructure parameters and MPS of screws. The MPS of pedicle screws was highly correlated with bone volume over total volume (BV/TV), trabecular thickness (Tb.Th) and trabecular separation (Tb.Sp) from micro-CT scanning. Conclusions Significant deterioration would occur in bone tissues with the decline of BMD level, and the MPS of pedicle screws was highly correlated with some microstructure parameters.