Comparison of ACAF and ACCF in the Treatment of Cervical OPLL (ACAF)

Comparison of Anterior Cervical Anteriodisplacement Fusion and Corpectomy Decompression Fusion in Treatment of Ossification of the Posterior Longitudinal Ligament: A Conservative Treatment- Controlled, Randomized, Open Label Clinical Study

Background: Dr. Shi recently proposed a new technique as Ossification of anterior decompression surgery, which is also called anterior controllable antedisplacement and fusion (ACAF) , for ossification of the posterior longitudinal ligament (OPLL) and cervical canal stenosis（CSS）. Yet, the effectiveness and safety should be further studied. Purpose: The aim of this study is to compare the effectiveness of clinical outcomes between ACAF surgery and Anterior cervical corpectomy decompression and fusion（ACCF）in patients with OPLL and CSS . A study hypothesis is that ACAF surgery outcomes will be equal even better and lower surgical complications which compared to ACCF surgery. Methods: This study is a randomized clinical trial with randomized, controlled, multicenter research design. The OPLL patients will be randomly assigned in one of the two treatment groups: ACAF surgery and ACCF surgery. Five outcome measures will be collected pre-operative for baseline, and then at1, 12, 24, 48, 96,240weeks post-operative follow-up visits, including: (1)JOA) .(2)VAS. (3)NURIC Graded .(4)NDI . (5) radiological parameter. After randomization, the ACAF group will receive anterior controllable antedisplacement and fusion and the ACCF group will receive anterior cervical corpectomy decompression and fusion.

Background: Although anterior and posterior decompression surgery are both reported to treat patients with myelopathy caused by OPLL（Posterior longitudinal ligament ossification）. The surgical strategy of the disease is still controversial when the OPLL is multilevel and severe. Novel techniques for better and safer results are required. Dr. Shi recently proposed a new technique as Ossification of anterior decompression surgery, which is also called anterior controllable antedisplacement and fusion (ACAF) , for ossification of the posterior longitudinal ligament (OPLL) with myelopathy. Yet, the effectiveness and safety should be further studied. Purpose: The aim of this study is to compare the effectiveness and safety of clinical outcomes between ACAF surgery and Anterior cervical corpectomy decompression and fusion（ACCF）in patients with OPLL. A study hypothesis is that ACAF surgery outcomes will be equal even better and lower surgical complications which compared to ACCF surgery. Methods: This study is a randomized clinical trial with randomized, controlled, multicenter research design. The OPLL patients will be randomly assigned in one of the two treatment groups: ACAF surgery and ACCF surgery. Five outcome measures will be collected pre-operative for baseline, and then at1, 12, 24, 48, 96,240weeks post-operative follow-up visits, including : (1) Japanese Orthopaedic Association (JOA) scales to assess the spinal cord functions.(2)Visual analogue scale (VAS) to assess pain relief. (3)NURIC Graded to assess walking function.(4) Neck Disabilitv Index(NDI) to assess cervical function . (5) radiological parameters to assess ossification forward distance. And the pre & postoperative radiological parameters, and surgical complications were also investigated. The investigator performing the outcome measures will be blinded to group assignment, and therefore will not participate in treatment. After randomization, the ACAF group will receive anterior controllable antedisplacement and fusion and the ACCF group will receive anterior cervical corpectomy decompression and fusion. Data Analysis: T test or wilcoxon rank sum test will be used to examine the differences in the five measures between groups and at the six different time frames with the α level set at 0.05. Chi square test will be used to compare the differences in the surgical complications data over time and between groups.

The main surgical procedures include discectomy of the involved levels, thinning of the anterior part of the involved vertebrae, intervertebral cages, anterior plate and screws installation, bilateral osteotomies of the vertebrae, and antedisplacement of the vertebrae-OPLL complex

Removal of the vertebral body，exposed ossification of the posterior longitudinal ligament，and then removed

Changes of patient-reported scores assessing improvement of spinal cord function underwent ACAF surgery compared to ACCF surgery

JOA total score up to 17 points, the lowest 0 points. The lower the score, the more obvious the dysfunction. Improvement index = post-treatment score - pre-treatment score, post-treatment score improvement rate = [(post-treatment score - pre-treatment score) / 17 - pre-treatment score] × 100%. By improving the index can reflect the improvement of patients before and after treatment and clinical efficacy. The improvement rate can also correspond to the commonly used efficacy criteria: cure is 100% improvement, improvement is greater than 60% effective, 25-60% is effective, and less than 25% is ineffective.

Changes of patient-reported scores assessing improvement of Walking function underwent ACAF surgery compared to ACCF surgery

NURIC Graded presented by NURIC in 1972 used to assess improvement of Walking function。s divided into 6 levels, 0 - Although there are symptoms, but not based on the basis of spinal cord involvement (no limb numbness, decreased muscle strength and other symptoms); Grade 1 - spinal cord involvement (numbness of the limbs, decreased muscle strength and other symptoms), but normal gait; Level 2 ---- mild gait abnormalities, does not affect the work; Level 3 ---- abnormal gait, affecting work; Level 4 ---- Need to support before walking; Level 5 ---- can not walk.

Changes of patient-reported scores assessing improvement of pain underwent ACAF surgery compared to ACCF surgery

Visual Analogue Scale/Score（VAS） score used to assess improvement of pain.This method is more sensitive and comparable. Draw a 10 cm horizontal line on the paper, one end of the horizontal line is 0, said no pain; the other end of 10, said the pain; the middle part of the pain of varying degrees.

Changes of patient-reported scores assessing improvement of quality of life and cervical function underwent ACAF surgery compared to ACCF surgery

Neck Disabilitv Index（NDI) used to assess improvement of Quality of life and cervical function.Clinical assessment of cervical function is commonly used, the scale includes the degree of pain, personal food, carrying objects, reading, headache, attention, work, driving, sleep and entertainment in all aspects. Each 5 points, the total score from 0 points (barrier-free) to 50 points (completely paralyzed), the higher the score the heavier the dysfunction.

Changes of patient-reported scores assessing ossification and spinal cord forward distance underwent ACAF surgery compared to ACCF surgery

radiological parameters used to assess assessing ossification and spinal cord forward distance.The results for the direct measurement of CT and MRI results, the minimum 0mm, the maximum 10mm, the greater the distance forward, indicating that the wider spinal canal, the better the spinal cord decompression, the better the surgical results.

Inclusion Criteria: patients aged 45-70 years, without gender limitation, are willing to sign informed consent; patients diagnosed with posterior longitudinal ligament ossification of the cervical spine; patients with limbs numbness, walking instability, banding and other spinal cord, nerve root compression symptoms, may be associated with urinary dysfunction, conservative treatment is invalid or gradually increased; Exclusion Criteria: Cervical ligamentous ossification, cervical trauma, cervical cancer, cervical tuberculosis and other inflammatory diseases; accompanied by thoracolumbar spine and other spine parts of the disease affect the clinical symptoms of patients; associated with amyotrophic lateral sclerosis and other motor neuron diseases and other neurological diseases; poor health condition, unable to tolerate surgery; patients (or their guardians) can not give full informed consent for adult dysfunction; patients who have participated in other clinical trials in the past 1 month patients with active hepatitis B (including HBeAg) or serological markers (HBsAg or / and HBeAg or / and HBcAb), hepatitis C, tuberculosis, cytomegalovirus infection, severe fungal infection or HIV infection; patients with active peptic ulcers within 3 months before randomization. patients with malignant neoplasms

Chen Y, Yang L, Liu Y, Yang H, Wang X, Chen D. Surgical results and prognostic factors of anterior cervical corpectomy and fusion for ossification of the posterior longitudinal ligament. PLoS One. 2014 Jul 7;9(7):e102008. doi: 10.1371/journal.pone.0102008. eCollection 2014.