Long-term Result of Circumferential Stabilization for Spondylolytic Spondylolisthesis by One Stage Posterior Approach

OBJECTIVE: The purpose of this study is to evaluate the efficacy of circumferential fusion with PLIF(posterior lumbar interbody fusion) using fusion cages and pedicle screw fixation by one stage posterior approach in the patients with spondylolytic spondylolisthesis. METHODS: Total 254 patients with spondylolytic spondylolisthesis underwent circumferential fusion during last 10 years. Among them, 117 patients could be followed for more than two years (mean follow up period: 27.4+/-5.5 months). The clinical and radiographic data were reviewed retrospectively. RESULTS: The clinical success rate according to Prolo's scale was achieved in 86.3% of patients and the solid bony fusion was occurred in 92.3%. The anterior slipping was reduced from 9.54+/-3.89mm to 3.26+/-2.46mm(p<0.001, paired t-test). Angular instability in lateral dynamic X-ray was improved in all case immediately after surgery. There were 3 cases of instrument-related complication (2.6%) such as loosening, disconnection, and cage retropulsion. CONCLUSION: The circumferential stabilization with PLIF using fusion cages and pedicle screw fixation by one stage posterior approach has been found to be an effective and safe procedure, demonstrating a high fusion rate and clinical success with a rare complications.

Multiple Spondylolytic Spondylolisthesis

Multiple spondylolytic spondylolisthesis is very uncommon, and surgical reports are also scarce. This study describes the clinical characteristics, radiologic findings and surgical methods in 18 cases of multiple spondylolytic spondylolisthesis encountered by the authors between January, 1993 and December, 1996. Two hundred and thirty spondylolytic spondylolisthesis patients underwent surgery at this hospital during the same period, and in 18 of these, the spondylolysis was multiple, an incidence of 7.8%. There were 16 cases of two level spondylolyses, 15 of which were at L4+L5, and one case at the L3+L4 level, as well as two cases of three level spondylolyses, one at L2+L3+L4 and the other at the L3+L4+L5 level. All 18 cases showed spondylolisthesis at L4/5 and two showed two-level spondylolisthesis at L4/5 and L5/S1. A decompressive laminectomy(Gill operation) was performed in all cases and in addition, two level 360degreesfixation with pedicle screws and PLIF with cages was applied in 16 cases, and two level PLIF with cages in the other two. All showed good post-operative results. In conclusion, the condition was more common in females and bilateral L4 and L5 pars interarticularis defect and L4/5 spondylolisthesis were more common. Decompressive laminectomy(Gill operation) and two level 360degreesfixation with pedicle screws and PLIF with cages was found to be an effective operative choice.