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Abstract
Pseudoarthrosis of the tibia, while perhaps less common today than in the past,continues to challenge orthopedic surgeons. Because it is usually very difficult to obtain union, coexisting problems of deformity, infection, and leg-length discrepancy are often not primarily addressed. In more complex cases with atrophic bone ends, substance defects, chronic osteomyelitis, or a combination of these, amputation may be the eventual outcome despite current techniques of internal fixation, bone grafting, and electrical stimulation.
Possible risk factors of non-union include systemic factors as old age, male sex, smoking, bad nutrition, debilitating general disease, some drugs and exposure to irradiation. Local factors include instability, presence of fracture gap, diaphyseal location of the fracture, bad soft tissue covering the fracture site, open fracture, short transverse fracture shape, presence of infection and bad surgical technique when dealing with these fractures.
The diagnosis of non union is unjustified until there is evidence, either clinical or radiological, that healing has ceased and that union is highly improbable. A fracture of the shaft of The tibia should not be considered a non union until at least 6 months after the injury because unless there is a gap, union requires 6-8 months especially after some local complications such as infections.
Many classification for nonunion are present, of them Paley classification is used in this study.
Diagnosis of nonunion depends on clinical diagnosis and radiological examination including x-ray especially stress views, computerized tomography (CT), bone scanning, magnetic Resonance imaging (MRI), osteomedulloangiography, positron emission tomography (PET), angiography, laboratory diagnosis and tissue biopsy.