Surgical Strategy for Cervical Myelopathy Due to Ossification of the Posterior Longitudinal Ligament: Part 2: Advantages of Anterior Decompression and Fusion over Laminoplasty

Study Design: Retrospective study of 27 patients who underwent anterior decompression and fusion (ADF) for treatment of cervical myelopathy due to ossification of the posterior longitudinal ligament (OPLL).

Objectives: To compare surgical outcome of ADF with that of laminoplasty.

Summary Of Background Data: During the period 1986 and 1996, laminoplasty was the only surgical treatment selected for cervical myelopathy at our institutions. According to surgical results of laminoplasty performed during this period, we have performed either laminoplasty or ADF for patients with OPLL since 1996.

Methods: We reviewed clinical data obtained in 27 patients who underwent ADF between 1996 and 2003. Mean duration of follow-up was 6.0 years (range, 2-10 years). Surgical outcomes were assessed using the Japanese Orthopedic Association (JOA) scoring system for cervical myelopathy. Surgical results of ADF were compared with those of laminoplasty, which was performed in 66 patients during the period 1986 and 1996.

Results: ADF yielded a better neurologic outcome at final follow-up than laminoplasty in patients with occupying ratio > or =60%, although graft complications occurred in 15% and additional surgical intervention was required in 26%. Neither occupying ratio of OPLL, sagittal shape of ossification, nor cervical alignment was found to be related to surgical outcome of ADF.

Conclusions: Although ADF is technically demanding and has a higher incidence of surgery-related complications, it is preferable to laminoplasty for patients with occupying ratio of OPLL > or =60%.