The clinical efficacy of anterior controllable antedisplacement and fusion with unsevered posterior longitudinal ligament in the treatment of multilevel cervical ossification of the posterior longitudinal ligament

English Keywords:Ossification of the posterior longitudinal ligament  Multilevel  Anterior controllable antedisplacement and fusion  Clinical efficacy

English Abstract:

  【Abstract】 Objectives: To evaluate the clinical outcome of anterior controllable antedisplacement and fusion(ACAF) with unsevered posterior longitudinal ligament(PLL) for the treatment of multilevel cervical ossification of the posterior longitudinal ligament(OPLL). Methods: Data of 73 patients with multilevel cervical OPLL who underwent ACAF in our hospital from October 2017 to November 2019 were reviewed retrospectively. The patients were divided into the unsevered group(n=42, 32 males and 10 females, averaged 55.8±9.7 years old and 2.4±0.4 years of follow-up) and severed group(n=31, 25 males and 6 females, averaged 56.7±11.4 years old and 2.3±0.3 years of follow-up). The operative time, blood loss, length of hospital stay, and complications of the two groups of patients were collected. The occupying rate of spinal canal, antedisplacement distance, decompression width, and anteroposterior canal diameter were measured on CT images before and at 12 months postoperatively to evaluate the decompression. The interspinous motion, intra-and extragraft bone bridging and changes in the total interbody height of fused vertebral bodies were observed on cervical anteroposterior and lateral images, dynamic X-ray, and CT images at 7d and 12m postoperatively to evaluate the fusion. JOA scores were recorded before surgery and at the final follow-up to assess the recovery of neurologic function. Results: The unsevered group showed less operative time(212.9±33.8min vs 257.4±33.2min), blood loss(489.8±199.0ml vs 598.9±241.3ml) and length of hospital stay(7.2±2.0d vs 8.9±3.2d) than those of severed group(P<0.05). The preoperative and 12m postoperatively occupying rate, decompression width, antedisplacement distance, and anteroposterior canal diameter were not significantly different between the two groups(P>0.05). The unsevered group demonstrated a higher fusion rate at 12 months[Interspinous motion(92.9% vs 74.2%), intra- and extragraft bone bridging(88.1% vs 61.3%)] postoperatively than that of the severed group(P<0.05). The unsevered group demonstrated less incidence of complications than that of the severed group(9.5% vs 32.2%, P<0.05). The JOA scores and neurologic recovery rates at the final follow-up were not significantly different between the two groups(P>0.05). Conclusions: ACAF surgery with unsevered PLL can ensure the decompression effect while reducing the operation difficulty, thus decreasing the operative time, blood loss, and incidence of complications, which can also accelerate postoperative recovery of patients and fusion.