Experience with five different intervertebral disc spacers for cervical spondylodesis.

The ventral spondylodesis with autologeous bone graft for degenerative disease of the cervical spine bears the disadvantage of complications and heavy pain at the superior pelvic straight. To reduce these problems the intervertebral disc spacer was developed. Between September 1997 and January 2002 we operated on 207 patients suffering from degenerative disease -- osteochondrosis and/or disc prolapse -- of the cervical spine. Without any patient selection, e. g. according to a randomized sample, we implanted the different disc spacer by a ventral approach after microsurgical discectomy and removal of the dorsal osteophytes by a high-speed drill. The Titanium disc spacer by Aesculap, Weber, Intromed, and Medinorm were used in 66, 54, 52 and 18 cases and the Carbonium disc spacer of AcroMed in 17 cases. We evaluated the handling, X-ray contrast, costs of implantation and the clinical results after 3 months and 1 year. All the five disc spacers are suitable for the ventral spondylodesis of the cervical spine. The titanium spacer from Weber is characterized by its comfortable handling and a price in the mean range. A good cost effectiveness and an easy handling is given by the Intromed-cage. The X-ray contrast of the Carbonium spacer by AcroMed is insufficient in the lower cervical spine. The handling is good, but the price is too high. The AcroMed, Medinorm and Intromed spacer have the tendency to migrate into the vertebral endplates. A final statement can only be given after the achievement of long-term results.