Anterior longitudinal decompression in the management of severe ossification of the posterior longitudinal ligament in the cervical spine.

The advantages of anterior surgery for severe ossification of the posterior longitudinal ligament in the cervical spine have been reported. However, it is more technically demanding and associated with a high risk of surgery-related complications. The purpose of this study was to evaluate the feasibility of longitudinal decompression techniques in anterior surgery for severe ossification of the posterior longitudinal ligament in the cervical spine. Between June 2008 and December 2011, twenty-two patients (16 men and 6 women; average age, 58 years [range, 45-72 years]) who underwent anterior corpectomy and fusion for severe ossification of the posterior longitudinal ligament were studied retrospectively. The clinical efficacy, canal narrowing ratio, fused segment height, and complications were investigated. After a mean 25.4-month follow-up, mean Japanese Orthopaedic Association score increased from 8.8±1.4 preoperatively to 14.0±1.2 at final follow-up (P<.05), an improvement rate of 63.5%±12.5%. Mean canal narrowing ratio decreased from 62.0%±6.0% preoperatively to 8.2%±4.9% postoperatively (P<.05). Mean fused segment height increased 2.3±0.5 mm from pre- to postoperatively and decreased 2.8±0.4 mm from postoperatively to final follow-up (P>.05). Five patients developed cerebrospinal fluid leakage, and 1 patient experienced hematoma. No instrument failure was observed, and all patients had successful fusion. Anterior longitudinal decompression is a relatively effective procedure in the management of severe ossification of the posterior longitudinal ligament in the cervical spine. It can be applied to treat closed-base ossification of the posterior longitudinal ligament (defined as no space between the lateral margin of the ossified base and the spinal canal lateral wall), but it is associated with a high risk of cerebrospinal fluid leakage.