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[Spondylolisthesis in childhood and adolescence].

Isthmic spondylolisthesis occurs in 4.4% of children. In general it is a benign condition. The majority of individuals with mild or moderate isthmic vertebral slip remain free of symptoms or get only mild symptoms. In children and adolescents with mild slip, primary treatment of pain symptoms is non-operative. Young children before the growth spurt need radiological follow-up for documentation of possible slip progression. If the slip exceeds 25% in a child, segmental fusion to prevent further progression should be considered. Uninstrumented posterolateral fusion is the method of choice for treatment of pain symptoms not responding to conservative measures in slips up to 50%. In severe slips (> 50%), anterior or combined fusion is necessary to prevent further progression of lumbosacral kyphosis. The clinical and subjective results of in situ fusion in this age group are satisfactory in 80-90% of cases. Slip reduction is possible. It requires internal fixation and is connected with a higher risk of complications. The results of slip reduction have not yet been shown to be superior to results after in situ fusion. It may be performed in cases of spondyloptosis with severe impairment of function and sagittal malalignment of the spine.