Cervical Alignment and Range of Motion Change after Anterior 3-Level Hybrid Surgery Compared with Cervical Laminoplasty: A Matched Cohort Study.

OBJECTIVES

Cervical alignment and range of motion (ROM) changes after cervical spine surgery are related to cervical biomechanical and functions. Few studies compared these parameters between posterior laminoplasty and anterior 3-level hybrid surgery incorporating anterior cervical discectomy and fusion (ACDF) with cervical disc replacement (CDR). This study is aimed to detect the differences of cervical alignment and ROM changes of the two surgeries in a matched-cohort study.

METHODS

From January 2018 and May 2020, 51 patients who underwent 3-level hybrid surgery incorporating ACDF with ACDR were included. A 1:1 match of the patients who underwent cervical laminoplasty based on age, gender, duration of symptoms, body mass index, and cervical alignment type was utilized as control group. General data (operative time, blood loss, etc.), Japanese Orthopaedic Association (JOA) score, VAS (Visual Analog Score), NDI (The Neck Disability Index), cervical sagittal alignment, and cervical range of motion (ROM) were recorded and compared.

RESULTS

Both groups gained significant improvement in JOA, VAS, NDI scores postoperatively (p < 0.05). Cervical alignment significantly increased in hybrid group and decreased in control group after surgeries (p < 0.001). ROM decrease was similar in two groups. For cervical lordosis, though cervical alignment angle in control group decreased, the final follow-up cervical alignment and cervical alignment changes were not significantly different between hybrid and control groups. For cervical non-lordosis, cervical alignment decreased in control group while increased in hybrid group. At final follow-up, cervical alignment and the changes between the two groups were significantly different. Both control group and hybrid group had similar ROM decrease after the surgery no matter whether there was cervical lordosis or non-lordosis. Hybrid surgery showed cervical alignments significantly improved and similar ROM preservation compared with control group at final follow-up both for 1-level and 2-level disc replacement subgroups.

CONCLUSIONS

The hybrid surgery demonstrated advantages of preserving cervical alignment and gaining similar cervical ROM preservation compared with cervical laminoplasty, especially for cervical non-lordosis. Given the importance of restoring lordotic cervical alignment, hybrid surgery may be preferred over laminoplasty to treat multilevel cervical disc herniation.