Abstract: Background: Ethylene oxide is widely used for secondary sterilization of bone allograft to reduce the risk of infection and associated complications. In this study the effects of ethylene oxide gas sterilization on the osteoinductivity of demineralized bone powder is investigated.
Materials and Methods: Two separate implants consisting 30 mg aseptically prepared, and 30 mg ethylene oxide-sterilized demineralized bone powder was placed into two different muscle pouches created in the paravertebral muscles of eighteen rats. After 4 weeks, they were removed with 0.5 cm normal surrounding tissue. Histological examination was done to determine the presence or absence of osteoinduction.
Results: All except one of eighteen aseptically prepared demineralized bone powder sites histologically contained new bone elements (94.4 %) and fourteen (77.7%) out of eighteen ethylene oxide sterilized demineralized bone powder sites showed evidence of new bone elements. There is no significant difference in osteoblast formation in the two groups (p>0.05).
Conclusion: It is concluded that ethylene oxide sterilization in 42˚C did not significantly reduce the osteoinductivity of demineralized bone powder. So, it can be considered as a suitable but not perfect method for secondary sterilization of demineralized bone powder.

Background: There are several methods to manage intertrochanteric fractures. The external fixation device could produce favorable clinical outcomes. Furthermore, it has a lower rate of morbidity. Therefore, this study aimed to compare two different methods for the reduction of the intertrochanteric fracture in elderly high-risk patients : external fixator vs. skeletal traction.

Materials and Methods: In this randomized clinical trial, 60 elderly patients (mean age, 78 years) with a pertrochanteric fracture were randomly assigned to the two groups and treated with either skeletal traction (group A) or external fixation (group B).

Results: Significant improvements were observed in all fractures acceptable reduction was achieved in 8 patients in group A and 26 patients in group B. The mean length of hospitalization was 14.3 days for group A and 2.2 for the group B. There was a significant difference between the two groups regarding the acceptable reduction of fracture and duration of hospitalization (P<0.05). At 12 months after surgery, the mean Harris hip scores were 57 and 66 in the group A and B, respectively.

Conclusion: M anagement with external fixator is an effective method for intertrochanteric fractures in elderly high-risk patients. Its advantages include quick and simple application, minimal blood loss, less radiation exposure, early discharge from hospital, low costs and favorable functional outcomes.