[Treatment of cervical ossification of the posterior longitudinal ligament using ultrasonic bone scalpel-assisted anterior controllable antedisplacement and fusion].

Objective: To investigate the technical key points and effectiveness of ultrasonic bone scalpel-assisted anterior controllable antedisplacement and fusion (ACAF) for treating cervical ossification of the posterior longitudinal ligament (OPLL).

Methods: Between June 2022 and December 2024, 11 OPLL patients underwent ultrasonic bone scalpel-assisted ACAF. The cohort included 8 males and 3 females, aged 49-74 years (mean, 56.7 years). The OPLL classification included 5 cases of mixed-type, 4 cases of segmental-type, and 2 cases of continuous-type cases. Ossification involved 2-5 spinal segments (mean, 3.2). Disease duration ranged from 2 to 18 months (mean, 6.2 months). The operation time, intraoperative blood loss, and complications were recorded. Pain improvement was assessed using the visual analogue scale (VAS) score, and neurological function was evaluated using Japanese Orthopaedic Association (JOA) score. Postoperative cervical CT and MRI were performed to measure spinal canal encroachment rate, spinal canal area, and spinal cord sagittal diameter.

Results: All operations were successfully completed. The operation time ranged from 174 to 360 minutes (mean, 255.9 minutes). The intraoperative blood loss ranged from 170 to 530 mL (mean, 345.9 mL). The C ₅ nerve root palsy occurred in 1 patient. No cerebrospinal fluid leakage, aggravated spinal cord injury, or recurrent/superior laryngeal nerve injuries occurred. All patients were followed 3-12 months (mean, 7.2 months). At last follow-up, VAS scores significantly decreased and JOA scores significantly increased compared to preoperative values ( P<0.05). According to the JOA improvement rate, the effectiveness was rated as excellent in 2 cases, good in 8, and fair in 1, with an excellent and good rate of 90.9%. Radiological re-examination revealed no implant loosening, screw breakage, or aggravated spinal stenosis. Postoperative spinal canal encroachment rate significantly decreased, while spinal canal area and spinal cord sagittal diameter significantly increased compared to preoperative measurements ( P<0.05).

Conclusion: For the treatment of cervical OPLL via ACAF, the intraoperative application of ultrasonic bone scalpel-assisted osteotomy enables precise vertebral groove creation and mobilization of the vertebra-ossification complex, thereby enhancing surgical safety and achieving satisfactory short-term effectiveness.