A new zero-profile implant for stand-alone anterior cervical interbody fusion

Several studies suggest fusion rates are higher with anterior cervical discectomy and fusion procedures if supplemented with a plate. However, plates may be associated with higher postoperative morbidity and higher rates of dysphagia. This led to the development of a cervical stand-alone cage with integrated fixation for zero-profile segmental stabilization.

We asked whether this new implant would be associated with a low rate of dysphagia and other short-term complications in patients having anterior cervical discectomy and fusion and would be able to achieve solid fusion and maintain postoperative reduction in pain.

We prospectively followed 38 patients with radiculopathy/myelopathy undergoing anterior cervical discectomy and fusion using the new implant. Intraoperative parameters, clinical features (Neck Pain Disability Index, visual analog scale score for neck/arm pain, Odom's criteria), and dysphagia scores were recorded. Radiographs were taken to assess implant failure. Thirty-four patients had a minimum 6 months' followup (mean, 8 months; range, 6-11 months).

Three patients at 6 weeks and one patient at 6 months complained about minor dysphagia-related symptoms. There was no hardware failure recordable and all patients had evidence of fusion. Compared to preoperatively, visual analog scale pain score and Neck Pain Disability Index were reduced at 6 weeks' followup without change during further followup.

The new cervical stand-alone anterior fusion device allows decompression and fusion with low complication rates. The incidence of chronic postoperative dysphagia was infrequent in comparison to published data. Prospective randomized trials with more patients and longer followup are necessary to confirm these observations.

Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.