Background and aim: Cervical degenerative disc diseases (CDDD) include various degenerative conditions often associated with cervical disc herniations (CDHs) that may result in radiculopathy and/or myelopathy. The first line management is conservative. In patients who need surgical management anterior cervical discectomy and fusion (ACDF), is the most accepted and widely performed spinal fusion procedure. In this study, we aimed to determine the outcomes of single or multilevel ACDF with polietereterketon (PEEK) cages in 152 patients (a total of 237 cages) with focus on the cage instability in terms of migration and subsidence that may occur in the early postoperative period.
Materials and method: A total of 176 consecutive patients who had undergone single-or multilevel anterior cervical discectomy with PEEK cage for CDDH from January 2015 to January 2021 were retrospectively evaluated.152 patients (237 PEEK cages) who found to be suitable for the study criteria were included. The clinical and radiological outcomes were evaluated at 1st and 3rd months.
Results: The age of the patients ranged from 25 to 80 years. 79 patients were operated from single distance, 56 patients from 2 distances and 17 patients from 3 distances. There were no postoperative cage extraction or fracture in any of our patients. Cage migration was observed in 15 cages in 12 patients without relevant clinical complaint. In 11 patients (11/152; 7.2%) a total of 14 cages (14/237, 5.9%) were found to be migrated at least 2 mm anteriorly up to the margin of the lower vertebra corpus on the 1 st month follow up. On second follow up radiographies at the 3 rd month no further displacement were observed in any of these 14 cages despite the same exercise program and not using neck collar.In 1 patient other than these 11 patients the PEEK cage was migrated inferiorly into the inferior end plate.There was no case of superior migration of the cage into the superior end plate and no posterior or sideways migration.Subsidence was not detected in any cage and functional radiological examination was present in all cases with maintained intervened disc distance height during the follow ups.
Discussion and conclusion: The use of PEEK cages without anterior plate instrumentation and without use of postoperative neck collar in single level and also multilevel ACDF provide satisfactory clinical and radiological results. The cage related complications can be avoided by careful clinical examination and appropriate use of cages confirmed by preoperative radiological imaging. In addition, radiological follow up of the cages is important to detect early complications related with the cage position.