Modified Procedure Of Instrumented Posterior Lumbar Interbody Fusion With Insert Cage For Adult Spondylolisthesis

Objective An analysis of consecutive adult patients treated surgically for lumbar spondylolisthesis by modified procedure of instrumented posterior lumbar interbody fusion with emphasis on clinical and functional outcomes and complications.Method The modified surgical procedure was definitive reduction of the spondylolisthesis using pedicle screw instrumentation following primary reduction using intervertebral disc space distraction and interbody fusion with insert cages and local morselized bone after decompressive laminectomy. A prospective, single-cohort, observational study of the clinical outcomes, radiological data and complications was assessed in a series of 34 patients with lumbar spondylolisthesis who underwent the modified surgery between January 2003 and September 2005. There were 15 males and 19 females with an average age of 54. 4 years from 27 to 72 years. According to Newman classification, there, were isthmic spondylolisthesis in 7,degenerative spondylolisthesis in 26 and traumatic spondylolisthesis in 1. The clinical outcomes were evaluated according to Oswestry Disability Questionnaire, Prolo lumbar post-operative function evaluation standard and the radiographic data to slipping reduction degree and interbody fusion condition.Result 34 cases were followed up over 6 months and the average time of follow-up was 20 months from 6-39 months. Post-operatively, the slipping degree reduced and the radiographic data had no obvious loss. Solid bony fusion could be obtained at least one year after operation from CT scan. The objective clinical outcomes of the Oswestry Disability Questionnaire were in average 34.5 before operation and 17.3 after operation. Prolo lumbar post-operative function evaluation standard showed good operative outcomes. The complications of peri-operative period included dural tearing in 1 (2. 9%), transient neurological deficits in 6(17. 6%), incorrect pedicle screw position in 1(2. 9%), hematoma in 2(5. 9%). The long-term complications included persistent low back pain inll, (32. 4%), persistent neurological deficits in 1(2.9%).No pseudoarthrosis was found.Conclusion The modified procedure described is an advanced and scientific method for treatment of adult lumbar spondylolisthesis.It offers advantages not only in substantial deformity correction, but also in suitable interbody cages choosen and normal sagital plane alignment restoration. We must pay attention to make orientation in operation and avoid complications such as nerve injury in operation.