RÉSUMÉ
Objective To investigate the setting property and compressive strength of β-TCP (β-tricalcium phosphate)/α-CSH (α-calcium sulphate hemihydrate) combined bone graft. Method β TCP/α CSH combined bone graft and distilled water were mixed with different ratio: 1 g∶0.1 mL、1 g∶0.2 mL、1 g∶0.3 mL、1 g∶0.4 mL、1 g∶0.5 mL, respectively. The initial setting time (Ti), final setting time (TF), compressive strength were recorded, and the X-ray diffraction (XRD) and the scanning electron microscope (SEM) were examined. Results The initial and final setting time of combined bone graft increased along with the increase of solid/liquid ratio. The Ti and TF were (4.6±1.3) min and (13.1±2.9) min respectively when the solid/liquid ratio was 1 g∶0.2 mL. The average compressive strength was 7.86 MPa in one day after setting, which was about two times higher than that of β-TCP alone. The XRD results showed that no other materials were produced except that α-CSH was transformed to CSD in the setting process. The SEM results indicated that thick CSD granules were adhered to the porous surfaces of β-TCP granules after setting. Conclusions The setting time and compressive strength of β-TCP/α-CSH combined bone graft could be adjusted by the different solid/liquid ratio.
RÉSUMÉ
Objective To investigate the epidemiological characteristics of multiple-injuries of bone and joint in the belief that a better knowledge of such injuries may help their prevention and treatment. Methods A retrospective study was done on the data of 346 patients with multiple-injuries of bone and joint who had been ad- mitted to our department from January 2001 to December 2004. On the basis of CAI's classification, the following data were statistically analyzed: gender, age, cause of injury, injured part, number of injured parts, associated injuries and mortality. Results Of the 346 injured patients, there were 278 males and 68 females, with an av- erage age of 32.8 years (9months to 89 years). Two hundred and twenty-six cases resulted from traffic accidents, 65 from crush by a heavy object, and 52 from falling. There were 159 fractures of shaft of tibia and fibula, 96 fractures of femoral shaft, 87 fractures of shaft of ulna and radius, 58 fractures of ankle and foot, 57 chest injuries, 50 knee injuries, 50 hip injuries, 49 injuries at the pelvis region, 46 wrist and hand injuries, 36 injuries of shoulder, 36 skull fractures, 33 fractures of humeral shaft, 23 spinal fractures, and 17 elbow injuries. Two hundred and forty-two patients had two parts injured, 83 had three parts, 20 had four parts, and one had six parts. The average number of injured parts was 2.3. Two hundred and five patients suffered from close injuries, and 141 from open ones. The associated injuries included skull and brain injury in 51 cases, chest injury in 23, abdomen injury in five, urine system injury in three, nerve and vessel injury in 21, shock in 78, and fat embolism in six. Five patients died. Conclusions Male young people tend to be the majority of victims of multiple-injuries of bone and joint. Traffic accidents result in most of such injuries. Since multiple-injuries mostly involve lower limbs, they are easy to diagnose while the associated close injuries involving brain, chest, abdomen and pelvic are likely to be overlooked or misdiagnosed. Strengthening safety education and technical training of first aid is important to im- provement of treatment and to decrease of disability rate and mortality.