Spine
-
This is a level IV retrospective descriptive study at a single institution. ⋯ 4.
-
Case-control study. ⋯ 4.
-
Secondary analysis of subjects in the control anterior cervical discectomy and fusion (ACDF) arm of Medtronic Investigational Device Exemption (IDE) trials for cervical disc arthroplasty (CDA). ⋯ 2.