ABSTRACT
Objective To design a new type of external fixator for bone fracture and verify its rationality and feasibility. Methods The frame and screw of stainless steel achieved fracture fixation in vitro with a threaded locking structure.At the same time the increasing thickness of body frame, the inclined nail holes and the raised bottoms were designed to greatly enhance the strength and overall stability of body frame.FEM (finite element method),measuring the relative displacement and stress distribution after axial load,was used to verify the rationality of the design.An animal experiment with sheep was used to verify the feasibility of fracture treatment. Results Simulated result of FEM indicated that the biggest relative displacement between the separated bones was 0.04 mm,which was much less than the minimum value 1 mm required for fracture healing.The maximum stresses applied on the frame of the fixator,fixator screw,and bone were 35,26,and 6 MPa, respectively, which was much less than the allowable stress. In the animal experiment, fracture site was fixed firmly after operation and was well cured 3 months later.Conclusion The design of this new device is feasible and it can be used as a new method of fracture treatment.
ABSTRACT
[Objective]To research the effect of using Ilizarov technique in bone transmission and fascia skin flap for large defeciency of bone and soft tissues of lower limb.[Method]There were 12 patients in our group,11 patients had severe compound trauma of the leg,one in arm.Bone defeciency range was 4～12 cm,average 8 cm,cotaneous defeciency was 4?5 cm2～14?5 cm2,and all of them had acute infection.Nine had been treated with leg lateral fascia skin flap,1 had been treated with leg fascia skin flap,1 had been treated with the opposide leg skin flap,1 had been treated with the arm fascia skin flap,in 12 bone transport,elongation range was 4～12 cm,average 8 cm.Eight had been used double arms external fixation device,4 cases had been used circle shape external fixation device.[Result]Totally 12 patients were followed up for 2～10.8 years(average,4.2 years) elongation part and compressed part healed naturally,all of the fascia shin flap were alive.No bone ununion and chronic osteomyelitis appeared.[Conclusion]Using Ilizarov bone transport technique and fascia skin flap is a good way for treating large defeciency of bone and soft tissue.Its advantages:(1)The wound limb can maintain stability by external fixatian device.The methed of the bone transportation can fill big section bone deficiency;(2) In the same time the fascia shin flap may be transported,and repair soft tissue deficiency,provide good condition to bone's healing and control infection;(3)The external fixation device can provide distraction and compression functions,this function makes elongation part and compressed part obtain the reasonable biomechanics condition which would be good to bone healing;(4)The course of bone transmission can stimulate bone repair mechanisms,to enhance the wound limb metabolism,increase blood supply circularation,the grown bone factor aggregation,enhance the body's initiative repair mechanisms and infection controlling mechanism;(5)In the protection of the external fixation device,the patient's wound limb can do early rehabilitation,thus can avoid osteoporosis and joint dyfunction because of the lone-term immobility;(6)To use these methods,the treatment period will be shortened,antibiotic application will be decreased,the treatment cost will be lower than other methods and complications will be decreased as well.
ABSTRACT
@#ObjectiveTo observe the clinical therapeutic effect of postoperative infection of fracture bone of lower extremity treated with external fixation device combined with closed irrigation.Methods32 patients of long bones fracture of lower extremities with postoperative infections were treated with composite external fixation device combined with focus clearance and continuing closed irrigation.ResultsThrough 1.5～3 years follow-up, there was no infection relapse in 31 extremities, 26 bones' fractures healed in half a year, there was no malunion such as crispation or angulation and there was no complication of serious anchylosis.ConclusionIt is an efficient way to treat postoperative infection of fracture bone of lower extremity with external fixation device combined with closed irrigation.