Single-level Bryan cervical disc arthroplasty: evaluation of radiological and clinical outcomes after 18 years of follow-up

Purpose: Many studies reported mid-term clinical and radiological outcomes after cervical disc arthroplasty. Only a few studies analysed the long-term results. The aim of the study was to evaluate the clinical and radiological outcomes in patients treated with single-level Bryan cervical disc arthroplasty after 18 years of follow-up. Methods: This study was a retrospective analysis of institutional databases concerning patients treated with Bryan cervical disc arthroplasty. SF36 PCS, NDI and VAS were used to evaluate clinical and functional outcomes. Standard, flexion–extension X-ray and MRI were used to evaluate the radiological results. Results: Fifty-seven patients treated with single-level Bryan cervical disc arthroplasty completed the 18-year follow-up. At the final follow-up, a residual movement was observed in 32 patients (56%). The treated level range of motion decreased from 10.1° pre-operatively to 6.1° at the last follow-up (p = 0.0021). The range of motion of the adjacent segments and of the cervical spine had no significant change. Disc degeneration of the adjacent segment after 18-year follow-up was observed in 77.1% of treated patients. Conclusion: The clinical and radiographic outcomes 18 years after surgery are acceptable. The treated level range of motion reduction and the adjacent segment degeneration seems not to affect the clinical results after 18 years of follow-up.