Complications of Multilevel Anterior Cervical Fusion

Abstract

Objective: Although anterior cervical fusion is a standard procedure for most anterior cervical lesions, multilevel anterior cervical fusion with or without instrumentation remains a challenge due to the complexity of decision making and the high rate of complications as reported in the literature. Patients and Methods: During the period from June 1994 to June 1999, 49 cases of multilevel segmental anterior cervical fusion were retrospectively reviewed. Levels of fusion were determined mainly according to clinical presentations and related magnetic resonance imaging (MRI) findings. A modified Smith-Robinson surgical procedure and tricortical autogenous bone graft taken from the anterior iliac crest were used in all reviewed cases. Instrumentation was indicated only when there were 3 or more fusion levels, and/or when instability was documented. Complications including a painful donor site, transient dysphagia, instrumentation failure, hematoma formation, and spinal cord injury were analyzed. Results: Thirty-six patients (73.5%) received 2 levels of fusion, 11 patients (22.4%) received 3 levels of fusion, and 2 patients (4%) received 4 levels of fusion. Sixteen of 49 (32.6%) patients received plate and screw fixation. All patients achieved solid fusion by at least the 12-month follow-up. Complications included a painful donor site in 18 patients (36.7%), transient dysphasia in 16 patients (32.6%), instrumentation failure in 4 patients (8%), donor site hematoma in 1 patient (2%), and spinal cord injury in 1 patient (2%). Conclusions: Although the fusion rate of multilevel segmental anterior cervical fusion can be maximized if an autogenous tri-cortical bone graft is used and the stability is reinforced with instrumentation, the morbidity remained high. Alternative fusion materials such as a cage with or without an autogenous bone graft should be considered to avoid a painful donor site; meticulous surgical technique with intermittent retraction blade relaxation may decrease the incidence of dysphasia. Proper patient selection is important for avoiding unnecessary fusion levels and instrumentation.