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Background:The target of fracture fixation is to stabilize bone till full healing and return of full function of injured extremity. The use of external fixation in lower extremity fractures of children usually reserved for open fractures especially in polytraumatized patients. In this study we tried to assess the effectiveness both clinical and radiological together with complications of using external fixators as a definitive tool of fracture fixation. Patients and Method:We analyzed the outcomes and complications of 92 consecutive closed lower extremity long bone fractures in 82 children (52 males). All treated by closed manipulation and stabilization of fracture by one of three types of monoplane external fixators (Hoffman, dynamic axial fixators and tubuler fixator).Results: 92 fractures in 82 children included this prospective study. Age range 5-14 years (average 7.6 years). Fixator applied for 6-9 weeks (average 8 weeks). Average follows up 21 months. Mean time for union 13 weeks (range 10 to 36 weeks). There were no cases of nonunion and low incidence of growth disturbances. All patients achieved a satisfactory outcome with little morbidity, early mobilization, and short period of hospitalization. Conclusion:External fixator is a useful modality in treatment of pediatric closed diaphyseal fracture with multiple systemic injuries. It provides good stability can be done early or following surgical management of life threatening conditions, less invasive, avoids disturbance of fracture haematoma, inexpensive and many of its parts can be reused.

This paper presents a single-substrate microstrip rectenna for dedicated radio frequency energy harvesting applications. The proposed configuration of the rectenna circuit is composed of a clipart moon-shaped cut in order to improve the antenna impedance bandwidth. The curvature of the ground plane is modified with a simple U-shaped slot etched into it to improve the antenna bandwidth by changing the current distribution; therefore, this affects the inductance and capacitance embedded into the ground plane. The linear polarized ultra-wide bandwidth (UWB) antenna is achieved by using 50 Ω microstrip line and build on Roger 3003 substrate with an area of 32 × 31 mm2. The operating bandwidth of the proposed UWB antenna extended from 3 GHz to 25 GHz at −6 dB reflection coefficient (VSWR ≤ 3) and extended from both 3.5 to 12 GHz, from 16 up to 22 GHz at −10 dB impedance bandwidth (VSWR ≤ 2). This was used to harvest RF energy from most of the wireless communication bands. In addition, the proposed antenna integrates with the rectifier circuit to create the rectenna system. Moreover, to implement the shunt half-wave rectifier (SHWR) circuit, a planar Ag/ZnO Schottky diode uses a diode area of 1 × 1 mm2. The proposed diode is investigated and designed, and its S-parameter is measured for use in the circuit rectifier design. The proposed rectifier has a total area of 40 × 9 mm2 and operates at different resonant frequencies, namely 3.5 GHz, 6 GHz, 8 GHz, 10 GHz and 18 GHz, with a good agreement between simulation and measurement. The maximum measured output DC voltage of the rectenna circuit is 600 mV with a maximum measured efficiency of 25% at 3.5 GHz, with an input power level of 0 dBm at a rectifier load of 300 Ω.