ANTERIOR LUMBAR VERTEBRAL TRANSLATION FOLLOWING TRANSLAMINAR SCREW FIXATION - A REPORT OF 5 CASES

Translaminar screw fixation is a good procedure for posterolateral spi nal fusion of one or two motion segments. Anterior translation of the upper fused vertebra occurred in 5 of our patients following this proc edure. A further fusion with pedicle screw fixation was needed in 2 of them. This complication has been previously reported after decompress ion operations on the lumbar spine. Translaminar screwing produces sli ght posterior distraction which pushes forward the upper vertebra. Thi s procedure should be avoided in cases with evert minimal anterior tra nslation before operation. Translaminar screw fixation is nit ideal te chnique for fusion of a degenerated segment when the upper vertebra ha s slipped posteriorly.