الفهرس 
Oestern and Tscherne Classification of Closed-Fracture Soft-Tissue InjuryOnly 14 pages are availabe for public view
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Abstract
Diaphyseal tibial fractures are the most common lower limb fractures worldwide. Despite advances in management, tibia fractures remain vulnerable to many complications, which often require secondary surgery. Potential complications include delayed union, non- union, malunion, compartment syndrome and infection.
Intramedullary nailing is a popular technique for the fixation of both closed and open tibial fractures, and this techniques seemed to be conducted in patients with non-unions and not in patients with acute long bone fractures when De Sahagun witnessed Aztec physicians placing wooden sticks into the medullary canals of patients with long bone nonunions.
The absence of either adequate fracture callus after a minimum period of 9 months or progression towards healing for 3 consecutive months was defined as a non-union in tibial fractures treated by ILN.
Most published data from large teaching hospital units quote rates for non-union and infection in nailed tibial fractures which range from 0% to 12% and 0% to 11%, respectively, with the higher figures relating to open type-IIIB tibial fractures.
Once non-union, exchange nailing considered the treatment of choice for all indicated cases.
Theoretically, exchange nailing requires only a small incision wound, produces less blood loss, is a simple technique, and allows early ambulation. Additionally, the reported union rate may be the highest among all techniques used.
Failures of exchange nailing has specifically been noted in long bone non-unions associated with extensive comminution at fracture site, large segmental defects, and metaphyseal– diaphyseal junctional fractures . Also exchanging the nail with nail of larger diameter cannot be done if the nail already inserted is of largest diameter as marketed by the manufacturer.
Problems of ununited fractures may be due to proximal or distal location of the fractures in the respective bones, undersized nail, extensive comminution or broken implants. All these factors lead to rotational instability at the fracture site even though axial and translational alignments have been suitably restored. Thereby it becomes paramount to control rotational instability at nonunion site by additional stabilizing mechanism . Augmentative plate fixation for the management of tibial non-unions after intramedullary nailing has been successfully attempted by few workers.
Nail dynamization is carried out also at least10–12 weeks postoperatively when slow or no progression to bone healing was observed.
“Dynamization” is a process of converting static intramedullary osteosynthesis into dynamic intramedullary osteosynthesis provide almost complete transfer of axial pressure on the bone fragments when critical opposition more than 50%, or when the fibrous callus provide stability of the bone fragments. Earlier it was considered that the task of dynamization is to promote callus remodeling.
Partial fibulectomy combined with the optimal axial compression provided by an Ilizarov frame represents a minimally invasive treatment which can avoid the need for bone grafting in non-unions without extensive bone loss or infection.
The Ilizarov method is more indicated in atrophic nonunion and in hypertrophic nonunion with hypometria and angular defects. In the cases where bone defect exceeded 2cm, bifocal consecutive distraction compression osteosynthesis technique was applied.
In the presence of infection, the current management of this kind of infection consists of two main objectives. Infection control, which usually is achieved by nail removal with debridement, lavage of the medullary canal, local delivery of anti- biotics by antibiotic-impregnated bead chains , and fracture union, which usually is accomplished by providing alternative fixation. The principle of antibiotic-impregnated beads is to fill the dead space and deliver high concentration of specific antibiotics to the infected sites simultaneously. An antibiotic-impregnated molded cement femoral component with a metal core has been used for stabilization and dead space management after infected total hip arthroplasty. According to this idea, some authors began using self-made antibiotic-impregnated cement rods to treat infection tibial non-union after nailing, and the good results were obtained.
Some useful alternative treatments for non-unions such as pulsed electromagnetic fields ,electrically pulsed current stimulation ,and extracorporeal shock wave therapy(ESWT) are considered to have promising results as reported over the past 20 years.
A variety of devices have been developed in order to produce electromagnetic fields to the fracturesite. Recent and more widespread PEMF devices utilize non-invasive inductive coupling and can be used along with every method of fracture fixation.
The mechanism of shock wave therapy in bone non-union is still not clear. ESWT may produce microfractures of bone, which, inturn, can stimulate neovascularisation, osteoblastvformation, and bone healing.