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Clinical and Radiological Outcomes of Skip-Level Cervical Disk Arthroplasty. BACKGROUND AND OBJECTIVES: The skipped, in-between indexed, level theoretically has higher chances of adjacent segment disease (ASD), especially in between 2 anterior cervical diskectomy and fusion (ACDF) constructs. However, this inference remains unclear. The objective was to compare cervical disk arthroplasty (CDA) with ACDF for noncontiguous cervical disk problems. METHODS: Consecutive patients who underwent skip-level anterior cervical diskectomies for symptomatic disk herniations or spondylosis involving noncontiguous pathologies of the subaxial cervical spine were retrospectively analyzed and divided into 2 groups: CDA and ACDF. Clinical and radiological outcomes were analyzed, including comparison of the range of motion (ROM), cervical lordosis, C2-7 Cobb angle, sagittal vertical axis, and T1 slopes. RESULTS: A total of 70 patients, 33 CDA vs 37 ACDF, completed at least 2 years of follow-up. Patients of the CDA group were younger (54.9 ± 8.6 vs 62.3 ± 9.9 years, P-value < .01) than ACDF. The incidences of radiological ASD were lower in the CDA than ACDF (18.2% vs 40.5%, P = .04) groups. One patient in the ACDF group had worsened symptoms caused by ASD of the initially skipped level that required a secondary surgery, whereas there were no reoperations for CDA. The ROM of both the skipped level and overall cervical spine (C2-7) were higher in the CDA group than those of the ACDF group (P-values = .04 and .01, respectively) at 2-year postoperation. The complication rates were no different between the 2 groups. CONCLUSION: Both skip-level CDA and ACDF can restore cervical lordosis, while the overall cervical ROM was well preserved in the CDA group but almost eliminated in the ACDF group. Skip-level CDA not only preserves motion at the indexed but also at the in-between skipped level, with lower incidences of ASD and higher ROM than ACDF. Therefore, to avoid a three-level fusion in the long run, CDA is the superior option for noncontiguous disk herniations or spondylosis that require surgery.