Extensive laminectomy for multilevel cervical stenosis with ligamentum flavum hypertrophy: more than 10 years follow-up

The aim of this research was to evaluate the long-term results of extensive laminectomy for the treatment of cervical spondylotic myelopathy due to multilevel cervical stenosis (MCS) with ligamentum flavum hypertrophy (LFH).

From January 2000 to December 2002, a total of 91 patients who underwent extensive laminectomy for MCS with LFH were included in this study to investigate the long-term outcome of this surgical option. All patients were presenting moderate-to-severe preoperative cervical myelopathy. The patients with cervical lordosis, without cervical kyphosis and instability, were included in our study through preoperative radiological examination. Clinical outcomes were evaluated by the Japanese Orthopedic Association (JOA) scoring system and by recovery rate (RR). The changes in curvature of cervical spine were determined by cervical curvature index (CCI). Range of motion (ROM) of the cervical spine was assessed by measuring the C2–7 Cobb angle on flexion and extension. The anteroposterior diameters and the drift-back distance of the spinal cord were calculated using the MRI image. The axial pain was measured by a visual analogue scale (VAS). Statistical analysis was performed using paired t test with significance set at P < 0.05.

Ninety-one (83 %) of the 109 patients completed the follow-up in this study. The mean duration of follow-up was 12.1 years. The preoperative JOA scores in these patients averaged 6.8, and the postoperative scores at the final follow-up averaged 14.5 (average RR 68.4 %). The CCI decreased significantly from 20.8 ± 2.1 preoperatively to 11.5 ± 1.8 at last follow-up (t = 15.31, P < 0.01). The cervical ROM at C2–7 decreased from 42.7° before surgery to 20.4° at the final follow-up (t = 21.16, P < 0.01). The increased anteroposterior diameters at the level of maximum compression together with the significant drift-back distance of the spinal cord suggested that decompression was complete. The postoperative VAS score suggested that the axial pain was mild (1.4 ± 0.8).

A series of clinical results were obtained after the extensive laminectomy for a long-term follow-up period exceeding 10 years. The extensive laminectomy may be an option for an alternative procedure for treatment of MCS with LFH.