Degenerative spondylolisthesis does not influence surgical results of laminoplasty in elderly cervical spondylotic myelopathy patients.

The objective of the study was to investigate the comorbidity of degenerative spondylolisthesis (DS), in elderly cervical spondylotic myelopathy (CSM) patients in our hospital, and the correlation between surgical results and preoperative DS. There are few studies on the outcome of laminoplasty for CSM with DS. A total of 49 elderly patients (>65 years old) who eventually had surgical treatment for CSM were evaluated. A slippage displacement of more than 2.5 mm at least at one level was classified to have a positive DS on flexion/extension radiographs (DS group). A slippage displacement less than 1.0 mm was considered a negative DS (non-DS group). Seventeen patients who had slippage of 1.0-2.5 mm were excluded from the study. The DS group (n = 15) included cases with DS at preoperation, while the remaining cases (n = 17) belonged to the non-DS group. The flexion/extension radiographs of the two groups were compared for range of motion and clinical results at 3 years after the operation. Of all elderly patients, 30.6% had DS. There was no significant difference between the two groups based on the clinical results. The range of motion of all cervical spines (DS group and non-DS group) was significantly limited. However, there was no significant difference between the two groups. New postoperative DS appeared in four patients, of which two were from the DS group and two from the non-DS group. These data suggest that degenerative spondylolisthesis does not influence surgical results in elderly cervical spondylotic myelopathy patients.