Surath Sanjaya Kumara
National Hospital for Neurology and Neurosurgery, UK
Scientific Tracks Abstracts: J Neurol Neurosci
Objectives: Does hypertrophy of posterior longitudinal ligament (HPLL) significantly contribute to cervical spondylotic myelopathy (CSM), when associated with cervical disc herniation (CDH)?
Although anterior decompression is a common and widely accepted surgical technique for cervical myeloradiculopathy, it is still difficult to determine whether HPLL should be removed during ACDF for CSM.
Materials & Methods: This single institution retrospective study analysed 56 patients presenting with CDH and associated HPLL with CSM during a time period of 4 years from 2012 to 2016. The presence of thickened HPLL was confirmed by T2-weighted Magnetic Resonance Imaging (MRI) scanning.
Preoperative Neurological function was evaluated using the Modified Japanese Orthopaedic Association (MJOA) Cervical Spine Myelopathy Functional Assessment Scale. All the patients were treated by a single/two level ACDF performed by a single surgeon. Removal or preservation of HPLL was decided upon the degree of satisfactory decompression intraoperatively following removal of disc-osteophyte complex. Surgical outcome was evaluated at the end of 12 months according to Odom’s criteria. Postoperative MJOA scores and spinal canal diameters were compared in the two groups.
Results: Out of 56 patients who underwent ACDF, HPLL was removed in 29(57.8%) and preserved in 27(48.2%). At the end of 12 months, 26(89.6%) patients who underwent removal of HPLL revealed excellent or good outcome scores according to Odom’s criteria, although 18 out of 27(74.1%) patients whom HPLL was preserved found to have similar Odom’s criteria. The difference in outcome was statistically significant at a p value of 0.036. The improvement of mJOA scores in removal group is statistically significant at 6 and 12 months follow up compared to the preserved group. (p=0.041). No significant difference in postoperative increase in spinal canal diameters observed between the two groups at follow up.
Conclusion: Removal of HPLL has a significant effect on surgical outcome when performed along with cervical discectomy during single/ two level ACDF.