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istraction osteogenesis (callotasis) has been widely used in patients with limb-length inequality or massive bone defects. This procedure, however, may be associated with a high incidence of physical and psychosocial complications. Callotasis telescoping on a locked intramedullary nail has been used to shorten the period of external fixation. Little attention has been given to the use of locked intramedullary nails in the treatment of complications after callotasis.Between 1990 and 1999, we used locked intramedullary nailing in 27 patients for the treatment of complications after distraction osteogenesis. There were 17 men and ten women with a mean age of 33.2 years (16 to 66). The nail was inserted at a mean of 3.4 weeks (0 to 15) after removal of the external fixator. Simultaneous autogenous bone grafting and soft-tissue reconstruction were also undertaken in seven and two patients, respectively.There was consolidation of the callus or docking site in all patients at a mean of 6.4 months (2 to 14) after surgery. The mean shortening of the callus was 0.7 cm (0 to 2.5). Two patients had infection at the site of a distal screw which resolved after removal of the nail. In 17 patients the nail was removed at a mean of 26 months after its insertion.Locked intramedullary nails are useful in treating complications after distraction osteogenesis in skeletally mature patients. The risk of infection should be borne in mind. Distraction osteogenesis (callotasis) has been widely used in the treatment of patients with leg-length discrepancy or a D massive bone defect.1 There is, however, a high incidence of complications including pin-track infection, fracture of the callus, nonunion of the docking site and delayed formation of callus. There may also be psychosocial complications and poor tolerance by the patient may result in failure or early termination of the procedure.2 Plaster casts or further periods of external fixation and plating have been used in the treatment of fracture or bowing of the callus and premature removal of the external fixator.2,3 Locked intramedullary nails, which have rotatory stability and maintain the length of long bones, have been widely used in the treatment of comminuted fractures. The technique of distraction osteogenesis over an intramedullary nail has also been described. [4][5][6][7] This procedure shortens the period of external fixation and allows an improved range of movement of the adjacent joints. Interlocking nailing after external fixation has also been described for the treatment of compound fractures of long bones. [8][9][10][11][12][13][14] Its use in the treatment of complications after distraction osteogenesis has, however, received little attention. Our aim was to evaluate the results of using locked intramedullary nailing in the treatment of complications after this procedure. Patients and MethodsBetween 1990 and 1999 we undertook 256 procedures for distraction osteogenesis in 223 skeletally mature patients. A total of 26 (10.2%) required internal fixation for complications ...

A systematic holistic mathematical programming (HMP) is proposed to formulate a mixed integer nonlinear programming (MINLP) model for one-step optimization of water-allocation and heat exchange network (WAHEN) designs with single-or multi-contaminant water streams. The proposed model formulation and solution strategy are believed to be superior to the available ones in the following aspects. First, a comprehensive representation combining two separate superstructures is adopted to capture the structural characteristics of the integrated WAHEN. Then, a hybrid optimization strategy integrating stochastic and deterministic components is developed for the resulting MINLP model and, also, an interactive iteration method is adopted based on sensitivity analysis to guide the search toward a potential global optimum. Finally, evolutionary strategies and manipulations are executed to enhance WAHEN configurations.Two illustrative examples are presented to demonstrate the validity and advantages of the proposed approach.

The title of this article should be corrected to "Mesoscopic simulation for the structural change of a surfactant solution using dissipative particle dynamics" because of an error in the editing process.