A novel surgical technique for the treatment of continuous-type ossification of the posterior longitudinal ligament with K-line negative

Objective To investigate a novel surgical technique for the treatment of patients with continuous-type cervical ossification of the posterior longitudinal ligament (OPLL) with K-line negative using anterior hinge-like osteotomy through ossification and antedisplacement of the vertebral-ossification compound, combined with posterior single open-door laminoplasty. Methods Four patients with continuous-type cervical ossification of the posterior longitudinal ligament (OPLL), showing straight and stiff cervical alignment without lordosis, and identified as K-line negative, underwent a novel surgical procedure. Initially, posterior single open-door laminoplasty was performed in combination with lower facet V-shaped osteotomy and lateral mass joint release. Subsequently, an osteotomy was conducted through the ossification ligament using a hinge-like technique, along with anterior displacing and pulling using pre-bent plates and screws, to restore cervical lordosis. The duration of surgery, amount of blood loss, and the following parameters were assessed using radiography, CT scans, and MRI: cervical lordosis, spinal canal enlargement, and medullary decompression. Pain levels were measured using the Visual Analog Scale (VAS), while disability was evaluated using the Neck Disability Index (NDI) and Japan Orthopedic Association (JOA) scores, both before and after surgery. Results The surgery was successful, with an average operation time of 240 ±38 minutes and a bleeding volume of 400 ± 50ml. Postoperative images revealed a significant enlargement of the cervical spinal canal, improved cervical lordosis compared to preoperative measurements, and resolved compression of the spinal cord. The postoperative patients experienced a significant improvement in their clinical symptoms, as evidenced by improved VAS, NDI, and JOA scores. This indicates that the novel surgery effectively provided sufficient decompression. Conclusions The novel technique of anterior hinge-like osteotomy through ossification and antedisplacement of the vertebral-ossification compound, combined with posterior single open-door laminoplasty, has demonstrated the ability to restore cervical lordosis and enhance the outcomes of single posterior laminoplasty in the treatment of cervical OPLL with negative K-line. This innovative approach offers a new and promising solution for treating complex cases of cervical OPLL.