Experience with Poly Ether Ether Ketone (PEEK) cages and locking plate for anterior cervical fusion in the treatment of spine trauma without cord injury

The purpose of this study was to determine whether spinal fusion using radiotransparent cages can be an appropriate treatment for traumatic injury of the cervical spine. This series included 30 patients aged 17-84 years (average 46 years) treated between October 1999 and June 2003 for traumatic injury of the cervical spine without neurological deficit or cord injury. There were two bifocal cases so that the study concerned 32 fusions. Injuries were: tear drop (n=1), serious flexion sprain (n=8), biarticular dislocation (n=4), serous hyperextension sprain (n=4), dislocation-fracture (n=1), uniarticular fracture (n=7), fracture-separation of the facet joints (n=4), post-traumatic herniation (n=3). For each injury, we measured pre and postoperatively and at last follow-up: the intersomatic angle, anterior displacement, and height of the intersomatic space at the center of the intervertebral disc. All x-rays were read twice, by two independent investigators. In the event of disagreement, the x-rays were read again by a senior surgeon and the main author of this article. Anterior fusion was achieved using a Poly Ether Ether Ketone (PEEK) (32%) and knitted carbon (68%) cage (cologne, Ostapek, Nexis) filled with cancellous bone harvested percutaneously from the iliac crest. The cage was associated with an anterior titanium plate fixation (Senegas, Euros and Orion, Medtronic). A posterior approach was associated if further stability was required (n=4 fusions). All patients were reviewed at minimum five months follow-up. Intersomatic fusion was verified on the standard x-rays (plus stress images and computed tomography at three months). Fusion was considered to be achieved if continuous bone lines crossed the graft and angle measurements remained stable, with the cage in the same position on successive examinations. One patient died from lung cancer five months after spinal fusion. All other patients survived with a mean follow-up of 24 months. Fusion was achieved in all cases, at mean 78 days. The mean intersomatic angle increased from 12 degrees kyposis preoperatively to 13 degrees lordosis postoperatively at last follow-up. Anterior displacement of the fractured vertebral body was 3 mm preoperatively and 0.3 mm postoperatively. Height in the middle of the intersomatic space was 5.3 mm preoperatively and 8.2 mm postoperatively. There were no cases of secondary displacement. This study demonstrated that fusion with an intersomatic cage associated with anterior pla