Selection of operative approaches for multilevel cervical spondylotic myelopathy by imageological score

A retrospective study of the operative approaches for multilevel cervical spondylotic myelopathy (MCSM) patients to establish an imageology scoring system and a prospective study to explore the clinical significance of the scoring system.

To develop and establish an imageology scoring system and explore its clinical significance for selecting the best surgical approach to treat MCSM.

MCSM often requires surgical intervention. A number of surgical methods are available, including anterior, posterior, and posterior-anterior united approaches. The key issue is to select an appropriate surgical approach that optimizes clinical outcomes. However, the selection of a surgical approach for MCSM is still controversial. As there is a lack of high-quality quantitative data and a uniform standard for selecting the best surgical approach, the choice is usually based on surgeon experience in practice.

A total of 226 MCSM patients who underwent different surgical approaches with satisfactory clinical results (>60% recovery rates) from January 1998 to June 2004 were retrospectively analyzed. The patients were divided into 3 groups according to the surgical approach they underwent: anterior, posterior, or posterior-anterior united approach. Six imageological indices closely related to MCSM were collected for each patient. The indices included the following: the stability of the cervical vertebra, the degree of spinal stenosis, the degree of spinal cord compression, hypertrophy of ligamentum flava, and the local (≤2 levels) or continuous (>2 levels) ossification of the posterior longitudinal ligament. The maximum likelihood method for discriminatory analysis was adopted to analyze the imageology indices, thus the imageology scores were obtained and the imageology scoring system was established. During the second stage of the study, 165 MCSM patients were prospectively analyzed between June 2005 and September 2008. The surgical approach with the maximum total score according to the imageology scoring system was regarded as the recommended surgical approach, but the actual surgical approach was determined by the surgeon's clinical experience. The patients were divided into 3 groups according to the actual surgical approach. Patients underwent either an anterior approach, posterior-anterior united approach, or posterior approach in groups A, B, and C, respectively. The following criteria were evaluated: perioperative and postoperative complications, Japanese Orthopedic Association (JOA) scores, and recovery rates. The correlation between the actual surgical approach and the recommended surgical approach by the imageology scoring system was analyzed.

The postoperative JOA score improved significantly in all the 3 groups. There were no significant differences in JOA scores (group A: 13.10±1.47, group B: 12.89±1.26, group C: 12.98±1.69) or recovery rates (group A: 61.71%±11.41%, group B: 60.21%±9.35%, group C: 60.93%±15.20%) at a 1-year follow-up in all the 3 groups. The correlation between the actual surgical approach and the recommended surgical approach was 87.27%, 90.16%, and 82.05% in groups A, B, and C, respectively.

The imageological scoring system proved to be effective for selecting a surgical approach for MCSM, which can make surgical techniques more quantified and standardized.