Comparative Study of Anterior versus Posterior Surgical Approaches in Patients with Cervical Spondylotic Myelopathy indicating both Approaches based on Benzel Criteria

Introduction & Objective:

Cervical spondylotic myelopathy is a progressive degenerative disease as the most common cause of myelopathic symptoms in elderly patients, and yet many controversies exist regarding the optimal surgical approachs. In lordotic patients with ventral or ventrodorsal compression less than 3 levels, both anterior and posterior approaches can be selected. The purpose of this study was to compare anterior versus posterior surgical approaches in patients with cervical spondylotic myelopathy indicating both approaches based on Benzel criteria for choosing the optimal surgical approach.

Materials & Methods:

This non-randomized clinical trial was performed among patients referred to the neurosurgery clinic of our hospital between 2019 and 2021. Patients enrolled in the study were evaluated for SF-36 (Ware, 1992), mJOA (Benzel, 1991) and Nurick (Nurjck, 1972) scores preoperatively. Then, according to the surgeon's diagnosis, the patients were divided into two groups. It should be noted that all surgeries were performed by one surgical team and after discharge, they underwent 4.5 and 9 months follow-up to re-determine all three scores and the obtained information was analyzed by repeated measures analysis of variance.

In this study, 120 patients with a mean (± standard deviation) age of 61.10 (± 2.41) years, of whom 63 were men (52.5%) and 57 were women (47.5%), were studied. In this study, 60 patients underwent anterior surgery and 60 patients underwent posterior surgery. There was no significant difference between the two groups in terms of age (P = 0.053), gender (P = 0.361), duration of symptomatology (P = 0.075), degree of lordosis (P = 0.052), and anterior- posterior diameters of canal
(P = 0.284). The mean of SF-36 was significantly better in the anterior group than the posterior group at 4.5 (P = 0.001) and 9 months follow-ups (P = 0.001). The mean mJOA was significantly better in the anterior group than in the posterior group at 4.5 (P = 0.002) and 9 months (P = 0.001) follow-ups. The mean score of Nurick before surgery and follow-up of 4.5 months (P = 0.745) and 9 months (P = 0.909) was not significantly different between the two groups.

The results of this study showed that both anterior and posterior approaches improve the condition of patients in follow-up, but in patients with anterior approach, postoperative satisfaction ranking was better.