OBJECTIVETo investigate the clinical effects of cervical disc prosthesis in patients of cervical spondylosis early, compared with the anterior cervical interbody fusion.

METHODSBryan disc prosthesis replacement applied in 21 case (22 levels) of cervical spondylosis, 27 patients (32 levels) were treated by the anterior interbody fusion. Clinic (JOA grade) and radiological (X-ray of bending, extending; left and right bending position) follow-up of 48 patients was performed preoperatively and postoperatively. Systemic radiographic study about stability and rang of movement (ROM) of replaced levels postoperatively was measured; meantime the ROM of adjacent levels of all cases was observed. CT or MRI scan were applied in 21 patients postoperatively to find out the pressure of the spine and heterotopic ossification in the replaced level.

RESULTSThere was no complication. Improvement in all case increased obviously, JOA score increased and stabilized postoperatively in all cases (P < 0.01). Replaced segment achieved stability and restored partial of ROM. There was no prosthesis subsidence or excursion. The adjacent ROM of the case treated by the anterior interbody fusion increased obviously (P < 0.01). No heterotopic ossification was found in the replaced level, but the deteriorated adjacent level of 1 case applied by the anterior interbody fusion occurred.

CONCLUSIONSBryan cervical disc prosthesis restore stability and partial motion to the level of the intact segment in flexion-extension and lateral bending in postoperational images; The adjacent ROM has not increased obviously. At the same time, it can achieve good short-term clinic effect in replaced level, compared with the anterior interbody fusion.