[Correction of lumbosacral kyphosis in high grade spondylolisthesis and spondyloptosis].

Spondyloptoses, but also high-grade spondylolistheses, usually only develop at the lumbosacral junction and are nearly always classed among dysplastic spondylolistheses. Kyphosis of the lumbosacral junction leads to compensation mechanisms with increased lumbar lordosis and straightening of the pelvic tilt with involvement of the hip and knee joints. Reconstructing a physiological sagittal profile by more or less complete repositioning with permanent fusion of only the lumbosacral motion segment is thus of primary importance in the surgical management of high-grade spondylolisthesis and spondyloptosis. This aim led to the following treatment modality: Dorsal repositioning following sacral dome resection with subsequent intersomatic fusion with the posterior lumbar interbody fusion (PLIF) technique. This procedure was performed in 11 patients between January 1995 and January 1998 for six grade IV spondylolistheses and five spondyloptoses. Four patients had undergone previous surgery. Measurements of the slip angle (Boxall), sagittal translation (Taillard), sacral inclination (Boxall), and sagittal rotation (Wiltse and Winter) were done in the follow-up and to check the postoperative results. Denis' pain scale was used to classify pre- and postoperative complaints as well as those of the last examination. Only one inadequate repositioning occurred in a previously operated patient who required instrumentation from L4 to S1 after a pedicle screw had been torn out at L5. In another previously operated patient, the dura was damaged intraoperatively and managed accordingly. Postoperatively, this patient developed a unilateral nerve root syndrome, which did not improve in the further course. Another patient developed decompensation of the adjacent cranial motion segment in the follow-up period. In ten cases complete or nearly complete reposition was achieved. Firm bone consolidation was seen in all patients. Complaints were markedly reduced in all patients compared to the preoperative status.