Treatment of Degenerative Spondylolisthesis of the Lumbosacral Spine by Decompression and Dynamic Transpedicular Stabilisation

PURPOSE OF THE STUDY The aim of the study was to present the effect and advantages of surgical decompression and dynamic transpedicular stabilisation in patients with degenerative spondylolisthesis of the lumbosacral spine. MATERIAL AND METHODS This prospective study involved patients undergoing dynamic transpedicular stabilisation using Isolock or Isobar TTL (Scient X, France) systems. Between June 2003 and June 2009, 65 patients were treated and followed-up. They were aged 35 to 75 years (average, 57.17 years), and there were 32 men and 33 women. Follow-up ranged from 1 to 6 years. Based on indications for surgery they fell into two groups. Group 1 included 52 patients with grade I or II degenerative spondylolisthesis or retrolisthesis. Group 2 (control) consisted of 13 patients with degenerative disc disease or failed back surgery syndrome. The disorder had always been manifested by combined axial and radicular symptoms. Treatment included posterior decompression of nerve structures by laminectomy in conjunction with semi-rigid stabilisation, without fusion. Followup clinical (VAS, ODI), neurological and radiographic examinations were carried out at 6 weeks, 6 months and 1 to 6 years after surgery. The VAS and ODI results of both groups were statistically analysed and compared. RESULTS During follow-up the ODI values decreased by 54 % (from 58.4 % to 26.8 %) and VAS values by 62 A) (from 7.9 to 3.0) as compared with the pre-operative values, and this was statistically significant. When both groups were compared, the VAS values decreased significantly (by 5.61) in Group 1, as compared with Group 2 (decrease by 3.54). DISCUSSION In the treatment of pseudospondylolisthesis, the semi-rigid stabilisation with spinal decompression, as presented here, is a convenient alternative to simple decompression without fixation or to various forms of instrumented or non-instrumented arthrodesis. A disadvantage associated with arthrodesis is a higher risk of ASD development; dynamic systems do not allow for reduction of spondylolisthesis and involve a change in sagittal spinal balance, and simple decompression carries the risk of slip progression and recurrent problems. CONCLUSIONS The authors demonstrated that decompression combined with semi-rigid stabilisation had a very good effect on the clinical state of patients with degenerative spondylolisthesis (retrolisthesis) at medium-term follow-up. The procedure was less effective in other indications. Semi-rigid stabilisation with Isobar TTL or Isolock systems prevented the progression of anterolisthesis or retrolisthesis; none of the patients experienced instrumentation failure. Neither symptomatic restenosis nor disc herniation was found in the instrumented segment. Semi-rigid stabilisation can, if necessary, be converted to fusion or disc replacement.