Preliminary clinical experience with polyetheretherketone cages filled with synthetic crystallic semihydrate form of calcium sulfate for anterior cervical discectomy and fusion

Purpose: Performing an anterior cervical discectomy by an interbody fusion is one of the surgical procedures for the treatment of cervical degenerative disc disease. Although high fusion rates have been reported with autogenous bone grafts, the immediate and long-term morbidity associated with an iliac crest harvest is well recognized. The objective of this study was to assess the efficacy of polyetheretherketone (PEEK) cages filled with a synthetic crystallic semihydrate form of calcium sulfate for an anterior cervical discectomy and fusion (ACDF). Methods: Twenty-four patients treated with an ACDF using PEEK cages with Stimulan at 27 various levels of the cervical spine, some patients at more than one level, were prospectively evaluated with a minimum of 12-month follow-up (mean: 18.4 months). The cervical lordosis and fusion status were assessed with radiographs including cervical spine plain films and a computed tomography scan. New bone formation was divided into three categories, namely, Grade I, II, and III. The clinical outcomes were evaluated with the visual analog scale (VAS) score for neck and arm pain at 6 and 12 months. Results: At approximately 12 months during the course of follow-up, the radiographs demonstrated Grade I, II, and III new bone formation at levels 2, 7, and 18, respectively. None of the patients experienced implant-related complications, such as cage failure or migration. Clinical outcomes evaluated with the VAS score demonstrated a significant improvement in both neck and arm pain. No complications associated with the use of PEEK cages were observed. Conclusion: The anterior cervical fusion using the PEEK cage with calcium sulfate demonstrated positive radiologic and clinical outcomes. Therefore, the use of the PEEK cage packed with Stimulan is a safe and effective alternative to autologous iliac bone grafts.