Graft migration or displacement after multilevel cervical corpectomy and strut grafting

Study Design. A retrospective review of consecutive patients with graft migration or displacement after anterior cervical corpectomy surgery was performed. Objectives. To examine the associated risk factors and results of treatment among patients who sustained graft displacement or migration after anterior cervical corpectomy surgery. Summary of Background Data. Graft migration or displacement after anterior cervical corpectomy is a potential complication that may require revision surgery, but because of the low incidence, the factors associated with graft movement and the results of treatment are not well defined. Methods. All patients who had undergone a cervical corpectomy were examined for graft migration or displacement. None of the patients had a previous cervical laminectomy or prior posterior cervical surgery. All the patients were treated with autogenous strut grafting after decompression. Results. Over a 25-year period, 249 consecutive patients underwent one- to five-level anterior cervical corpectomies and strut grafting. All the patients were fused using autogenous bone grafts (iliac crest or fibula). During the postoperative period, 16 of the patients (10 women and 6 men; average age, 61.4 years) experienced migration of their grafts. The average follow-up period was 4.7 years (range, 2-12 years). The graft migration rates increased with more levels of fusion (odds ratio of 1.65 for having a displaced graft with each additional level): 4 of 95 single-level grafts, 4 of 76 two-level grafts, 7 of 71 three-level grafts, and 1 of 6 for four-level grafts. Of the 16 patients with graft migration, 14 had procedures involving a corpectomy of C6 with a fusion inferiorly extending to the C7 vertebral body (P = 0.001, statistically significant difference). Of these 16 patients, 5 underwent revision surgeries acutely for displacement and associated fracture of the inferior graft and vertebral body junction. None of the patients sustained a neurologic or respiratory complication as a result of graft migration ordisplacement. All of the patients went on to successfulfusion. Conclusions. This study demonstrated that a greater number of vertebral bodies removed and a longer graft are directly related to an increased frequency of graft displacement. Graft displacement may require revision surgery, but no patient in this study experienced a permanent adverse result from this complication. Corpectomies involving a fusion ending at the C7 vertebral body were associated with a higher rate of graft migration.