Anterior cervical discectomy with or without fusion with acrylate. A randomized trial.

STUDY DESIGN

A prospective randomized trial with assessment of treatment results by an independent observer and by patient questionnaire.

OBJECTIVES

This study evaluated whether implantation of polymethylmethacrylate after anterior cervical discectomy improved clinical results and whether polymethylmethacrylate provided a solid bony union with preservation of anatomical relations of the cervical spine.

SUMMARY OF BACKGROUND DATA

Discectomy without fusion disturbs anatomical relations of the cervical spine. Use of an autologous bone graft frequently causes donor-site complications. Therefore, synthetic materials such as polymethylmethacrylate have been used instead of bone to obtain spinal fusion. Whether these implants improve the clinical results of anterior discectomy is unknown. In addition, the radiological follow-up of discectomy with polymethylmethacrylate has hardly been investigated.

METHODS

Between April, 1986, and April, 1990, all patients with radiologically proven cervical disc pathology and a radicular syndrome were eligible for this study. The primary endpoint of the study was the clinical result after 2 years. Assessment of the result was rated both by an independent observer using Odom's criteria and by the patient using a written questionnaire. Before surgery and during follow-up, radiographs were obtained.

RESULTS

Two patients died during follow up. A good result was obtained in 28 of 42 patients (70%) treated with polymethylmethacrylate and in 30 of 39 patients (77%) of patients treated with discectomy only. Pre-operative neck pain subsided earlier if polymethylmethacrylate was used, but the difference was temporary and clinically insignificant. The use of polymethylmethacrylate resulted in a significant lower bony union rate. Polymethylmethacrylate frequently migrated into adjacent vertebrae.

CONCLUSIONS

No relevant clinical differences between treatments were found. The radiological results of anterior discectomy with polymethylmethacrylate were inferior to those of discectomy only. Based on these results, the use of polymethylmethacrylate to obtain fusion after anterior discectomy is not recommended.