Analysis of the Correlation Between Cerebrospinal Fluid Space and Outcomes of Anterior Controllable Antedisplacement and Fusion for Cervical Myelopathy Due to Ossification of the Posterior Longitudinal Ligament

Abstract

We investigated whether the cerebrospinal fluid (CSF) space on magnetic resonance imaging (MRI) correlates with the outcomes of anterior controllable antedisplacement and fusion (ACAF) for ossification of the posterior longitudinal ligament (OPLL). A total of 53 patients with OPLL who had undergone ACAF were enrolled. The Japanese Orthopaedic Association (JOA) scale, visual analog scale, and neck disability index were used to evaluate the clinical outcomes. The area of CSF space and spinal cord on T2-weighted MRI, the occupying rate of the CSF space and spinal cord, and the postoperative MRI score of the CSF space were measured. The patients were divided into 2 groups according to the JOA score improvement rate (IR). The relationship between the postoperative MRI score and the JOA score IR was analyzed. The patients in group A experienced better recovery compared with those in group B regarding the JOA, visual analog scale, and neck disability index score at the final follow-up visit. On both axial and sagittal T2-weighed MRI, patients in group A experienced lower improvement of the area of the spinal cord than in group B (P > 0.05). However, the mean improvement in the CSF space in group A was better than that in group B (62.86 ± 30.05 mm2 vs.-6.36 ± 24.58 mm2; P < 0.05), with a greater occupying rate of CSF space in group A at the final visit. A strong correlation was noted between the JOA score IR and postoperative CSF space score (P < 0.01). These results suggest that ACAF could provide good decompression of the spinal cord and neurological improvement. Also, recovery of the CSF space correlated closely with the surgical ACAF outcomes for cervical myelopathy due to OPLL.