**2.2 Bryan Cervical Disc Prosthesis**

Bryan Cervical Disc Prosthesis (Medtronic Sofamor Danek, Memphis, Tennessee) consists of a nucleus made of polyurethane between two titanium alloy endplates in a clamshell configuration. (Figure 2) There are two bearing surfaces in the arthroplasty at the interfaces between the nucleus and the endplates. A polyurethane sheath attaches to the endplates and surrounds the nucleus. Sterile saline is injected between the outer sheath and the nucleus as lubricant. The endplates have a titanium porous coating for bone ingrowth and a small flange anteriorly to prevent posterior migration.

(Courtesy of Medtronic Sofamor Danek, Memphis, Tennessee)

Fig. 2. Bryan Cervical Disc Prosthesis
