Anterior decompression with fusion versus posterior decompression with fusion for massive cervical ossification of the posterior longitudinal ligament with a ≥50% canal occupying ratio: a multicenter retrospective study

Abstract

Background context: Previous studies have shown that compared with laminoplasty, anterior decompression with fusion (ADF) is superior for postoperative neurologic improvement in patients with massive cervical ossification of the posterior longitudinal ligament (OPLL) with a ≥50% canal occupying ratio. However, it is unknown which method, ADF or posterior decompression with fusion (PDF), is more effective for the treatment of massive OPLL.

Purpose: This study aimed to investigate the surgical outcomes of ADF and PDF for the treatment of massive OPLL.

Study design: A multicenter retrospective case-control study was carried out.

Patient sample: A total of 61 OPLL patients with a ≥50% canal occupying ratio were included in this study. The mean age of the patients was 60.9 years (49 males and 12 females); 39 patients (31 males and 8 females, average age 61.1 years) underwent ADF, and 22 patients underwent PDF (18 males and 4 females, average age 60.6 years).

Outcome measures: The data collected from both groups included age, gender, neurologic symptoms evaluated based on the Japanese Orthopedic Association score, neck pain assessed using the visual analogue scale, and radiographic parameters, including cervical lordosis and the OPLL canal occupying ratio.

Methods: Clinical and radiological outcomes were compared between the ADF and PDF groups with a minimum of 2 years follow-up.

Results: There were no significant differences in the postoperative neurologic recovery rate between the two groups. However, in patients with kyphotic alignment (C2-C7 angle <0 degrees), the recovery rate was higher in the ADF group. Postoperative cervical pain was greater in the PDF group. The improvement in cervical alignment at C2-C7 was greater in the ADF group. The operating time was longer in the ADF group, whereas the intraoperative blood loss was greater in the PDF group. Approach-related complications were more frequently observed in the ADF group than in the PDF group.

Conclusions: The present study demonstrated that the postoperative recovery rate was similar in the ADF and PDF group. In patients with massive OPLL with kyphotic alignment, neurologic recovery rate in the ADF was superior to that in the PDF (in situ fusion). Additionally, postoperative neck pain was less severe in the ADF group. However, the occurrence of perioperative complications was more common in the ADF group.

Keywords: Anterior decompression with fusion; Canal occupying ratio; Complications; Neurologic recovery; Ossification of the posterior longitudinal ligament; Posterior decompression with fusion.