[Transaxial spongiosa-plasty and ventral, temporary atlanto-axial fixation for therapy of dens pseudarthrosis].

Purpose: According to literature there is a pseudarthrosis rate of about 1% up to 64% depending on the treatment of the dens fracture (16). Generally the treatment of dens pseudarthrosis consists of the fusion of the joint C1/C2 with or without dens resection. Now, a method is presented whereby, on the one hand the pseudarthrosis is treated, while on the other hand the anatomical structures and physiological function of the joint C1/ C2 are restored.

Method: The operation consists of a gradual outboring of the base of the dens and the dens axis and filling with autologous cancellous bone. Then follows a lateral, temporary transarticular screw fixation of C1/C2 which guarantees an immobilisation of the filled out dens. A halo-body-jacket is then applied. The removal of the screws of the temporary fixation follows three months post operatively after X-ray control. Then physiotherapy of the cervical spine follows.

Results: During 7/93 and 7/97 this operation was carried out on 11 patients. In 9 cases compression screw osteosynthesis was primarily conducted and in 2 cases conservative therapy had preceded. The X-ray follow ups showed on an average of 14 month a stable bony fusion in 10 patients, the clinical follow up examinations on an average of 14 month a normal function.

Conclusion: The operation presented is indicated in case of dens pseudarthrosis because this accomplished a definite bony fusion without disturbance of the function of the joint C1/C2 in patients not older than 60 years. Disadvantages are to be found in the intraoperatively high X-ray radiation and the 3 month immobilisation.