gms | German Medical Science

Objective: Study Design: This is a prospective, randomized and controlled study, approved by the local ethics committee of Saarland (Germany), N° 209/06

Summary and background data: Anterior cervical discectomy and fusion (ACDF) including plate fixation is an accepted technique for treatment of symptomatic degenerative disc disease. Plate fixation has been introduced to improve stability, reduce pseudarthosis rate and improve the clinical result. Until now titanium is the material of choice for plate creation because of it is stability and biocompatibility. However, there are some disadvantage such as stress shielding, screw dislocation and imaging artefact. These negative side effects of titanium plate makes it necessary to think about new material. Bioresorbable plates were developed and thought to solve this problem. The aim of this study was to compare clinical results, segmental motility, MRI compatibility and change of the bone density of a cervical spine segment treated with bioresorbable versus titanium plate treatment.

Methods: 40 patients with a one-level cervical radiculopathy scheduled for surgery were randomized for anterior discectomy and fusion (ACDF) with bioresorbable plate (20 patients, study group) or titanium plate (20 patient, control group). Follow-up examinations were done using a Visual Analogue Scale (VAS) with regard to neck and arm pain, Neck Disability Index (NDI). Radiostereometry was performed immediately after operation, after 6 weeks, 3, 6 and 12 months. MRI of the cervical spine was done immediately after operation, after 3, 6 and 12 months in order to assess postoperative changes, such as effusion, haematoma and swelling. Computer tomography of the operated cervical spine segment was done to assess bone signal density, expressed in HU.

Results: Three dimensional analysis of segmental motion (left-right, cranio-caudal, and posterior-anterior) did not reveal any statistical difference between the two groups at any examination time after operation (p>0.05). The VAS and NDI did not differ between the two groups after 6 months (p>0.05). The rate and speed of fusion as evaluated on the CT of the cervical spine segment was similar in both groups.

Conclusions: Anterior plate fixation using a bioresorbable plate has the same fusion progress and stability, as Titan. During the study no complications, such as soft tissue inflammation, swelling and infection were seen.