[Application of restorative laminoplasty combined with spinous process osteotomy and internal fixation for treatment of degenerative scoliosis].

Abstract

Objective: For treatment of mild degenerative scoliosis (DS) complicated with lumbar canal stenosis (LCS), posterior decompression and the spinal canal enlargement with spinous process osteotomy was performed in combination with fusion and pedicle screw instrument fixation.

Methods: Between 1999 and 2003, 18 male and 26 female elderly patients (with mean age of 63 years, ranging from 47 to 72 years) with DS complicated with LCS were treated with the described surgical procedures, including 25 with single segment lesion and 19 with involvement of 2 segments. A posterior medical incision from one vertebra superior to the target fusion area till the vertebral segment below it was made for spinal exposure. Undermining enlargement of the spinal canal was carried out according to the segments of the stenosis; in some cases the intervertebral disc was resected. Osteotomy was subsequently performed at the base of the spinous process, and the bony defect was covered with the spinous processes. Finally Moe fusion and Isola (17 cases) or Diapason (27 cases) instrument fixation were performed. The therapeutic effects were evaluated according to Oswestry scores and postoperative imaging examinations.

Results: The average follow-up period was 3 years, ranging from 1 to 4 years. Thirty-three patients were followed up for one year and 93.9% of them had excellent or good outcome; 27 patients were followed up of 2 years and showed a rate for excellent or good results of 88.9%. Both sagittal and transverse diameters of the lumbar spinal canal were increased obviously as found by CT scanning without spinal canal scar. A rate of 92.6% of the ostetomized spinous processes had bony fusions. Successful covering bone healing was achieved in a mean of 4 months after surgery. Compressive vertebral fractures superior to the fixed segments occurred in 2 cases, including 1 with pedicle screw loosening and the other with pedicle screw breakage. Another patient had delayed wound healing. No recurrence of LCS, spondylolisthesis and decompensation, or pseudarthrosis of the spine was observed in these cases.

Conclusion: The described surgical procedures for DS can decrease the occurrence of spinal canal scar and promote the healing of the covering bone, and can be a satisfactory treatment for mild DS complicated with LCS in the lumbar sagittal curve.