Traumatic cervical spinal cord injury after cervical laminoplasty for ossification of posterior longitudinal ligament: a case series

Study design A retrospective review of a case series of five participants. Objective To elucidate the effects of post-cervical laminoplasty on the clinical pathophysiology of traumatic CSCI. Summary of background data Cervical laminoplasty has been widely performed with good results in individuals for cervical myelopathy. However, no reports have thus far referred to the incidence of traumatic cervical spinal cord injury (CSCI) after previous history of cervical laminoplasty. Setting Spinal Injuries Center, Japan. Methods From 2008 to 2017, 999 cervical myelopathy individuals were treated by cervical laminoplasty in our institution. Of these, only five participants were subsequently emergency transported to our institution caused by traumatic CSCI. The pathology of five participants were cervical ossification of posterior longitudinal ligament (C-OPLL). The changes of cervical sagittal range of motion (ROM) and the morphology of OPLL were radiologically evaluated. Moreover, the mechanism of injury, the level of injury, and neurological evaluations were discussed. Results All of the participants demonstrated ankylosed cervical spine due to developing OPLL and spontaneous bony facet and laminar fusion on post-laminoplasty. A significant difference in cervical ROM was observed between pre-laminoplasty and 6 months post-laminoplasty (p = 0.0065). Three participants were extension injury and the other two were flexion injury. Conclusions All of the five traumatic CSCI participants had a history of previous cervical laminoplasty for C-OPLL. Cervical laminoplasty for C-OPLL might lead to cervical spine with rigidity and ankylosing due to developing OPLL and bony facet and laminar fusion, and might have a risk for traumatic CSCI.