Outcome Evaluation of Modified Uninstrumented Open-door Cervical Laminoplasty for Ossified Posterior Longitudinal Ligament with Cervical Myelopathy

Study Design This was a retrospective study. Purpose To evaluate the short term outcomes of a novel self-developed technique of performing uninstrumented open-door cervical laminoplasty (ODCL) in patients with cervical myelopathy secondary to ossified posterior longitudinal ligament (OPLL). Review of Literature Published literature on cervical laminoplasties largely focuses on the outcomes of instrumented variants. Materials and Methods Retrospective data were collected from 54 patients who underwent uninstrumented ODCL for cervical OPLL at a single institution from January 2010 to February 2017. The preoperative and postoperative modified Japanese Orthopaedic Association score (mJOA) and Nurick grading were documented. Cervical lordotic angle at C2-C7 and range of motion (ROM) were obtained from the preoperative and postoperative lateral cervical radiographs in neutral and flexion extension views, respectively. Descriptive and analytical statistics were generated by SAS 9.4 University Edition (SAS Institute, Cary. North Carolina, USA). Results The average age was 58.6 ± 7.8 years. The average time of presentation from the onset of symptoms was 7.6 ± 3 months. Of the 54 patients who were included in the study, majority (48.14%) had segmental type of OPLL while C3–C6 was the most commonly operated level (66.67%). The mean operating time was 115 ± 31 min with a mean blood loss of 165.9 ± 75 ml. There was a significant improvement in the mJOA scores (9.2 ± 1.1-13.7 ± 0.9, P < 0.0001) and Nurick grading (3.4 ± 0.8-1.6 ± 0.5, P < 0.0001) at 24-month followup. Preoperative C2–C7 angle had an average decrease of 4.5° at 24-month followup (19.3 ± 7.2-14.8 ± 8.8, P < 0.0001). There was a mean reduction of 4.3° ± 3.78° noted in the C2–C7 ROM between the preoperative and final followup. Conclusion Uninstrumented ODCL is an easily reproducible and economical alternative to the standard instrumented laminoplasty with equivalent short term outcomes. This technique is a valuable option in the treatment of cervical OPLL, especially in regions with scarce resources.