Expansive lumbar laminoplasty for degenerative spinal stenosis in patients below 70 years of age

We reviewed the clinical and radiological results of patients with lumbar degenerative spinal stenosis who underwent expansive laminoplasty with a mean follow-up term of 5.6 years. Twenty seven patients underwent open- door-type expansive lumbar laminoplasty, which has both decompression and stabilization effects. Clinical results were assessed based on the score system devised by the Japanese Orthopaedic Association (JOA score). The number and causes of repeat surgery were also evaluated. Radiological changes, such as degenerative scoliosis and spondylolisthesis, were evaluated at the operated levels and at levels L1-L5. There was marked recovery of clinical symptoms assessed by pre- and postoperative JOA score. Nearly 80% of patients obtained good or excellent results. Only one patient (4%) required additional surgery, which involved discectomy at the caudal level of the laminoplasty. Radiographic evaluation revealed that postoperative changes of spondylolisthesis and scoliosis were slight both in the expanded area and the L1-L5 levels. Range of motion of the disc space angle in the expanded area showed a significant decrease postoperatively. However, pre- and postoperative radiological changes showed no significant correlation with JOA score changes and repeat surgery. In conclusion, lumbar fusion after posterior decompression in active patients with spinal stenosis offers satisfactory clinical results concomitantly with a relatively small risk of repeat surgery.