Abstract: A spring member for an artificial intervertebral disc includes a substantially annular body including an axially extended bore therethrough defining a passageway. A seat extends radially inward towards the bore for seating therein a bearing member for adjusting and compensating vertebral disc motion. An engagement member extends radially outwardly from the bore for engaging a housing member and securing the spring member within the housing member. The spring member absorbs compressive loads between the bearing member and the housing member while controlling motion and position of the bearing member.

Abstract: A spring member for an artificial intervertebral disc includes a substantially annular body including an axially extended bore therethrough defining a passageway. A seat extends radially inward towards the bore for seating therein a bearing member for adjusting and compensating vertebral disc motion. An engagement member extends radially outwardly from the bore for engaging a housing member and securing the spring member within the housing member. The spring member absorbs compressive loads between the bearing member and the housing member while controlling motion and position of the bearing member.

Abstract: An artificial intervertebral disc including housing members including spaced inner surfaces facing each other and oppositely facing outer surfaces for engaging spaced apart intervertebral surfaces; self-adjusting bearing mechanisms operatively disposed between the inner surfaces for moving relative to the housing members to adjust and compensate for vertebral disc motion; and positioning ring for controlling motion and position of the bearing mechanisms and for absorption of compressive loads. An artificial intervertebral disc including housing members having an oval recess on the inner surfaces; oval bearing mechanisms operatively disposed within the oval recess between the inner surfaces for moving relative to the housing members to adjust and compensate for vertebral disc motion; and oval positioning ring. A spring member for an artificial intervertebral disc including a substantially annular body having an axially extended bore therethrough defining a passageway.

Abstract: The present invention provides a wear-resistant titanium alloy orthopedic device. Also provided is a method of forming a wear-resistant titanium alloy orthopedic device by deeply diffusing oxygen into the titanium alloy device. A method of hardening a device formed of titanium by deeply diffusing oxygen into the titanium alloy device is provided.

Abstract: A screw and rod fixation assembly for fixing a screw and a rod, the assembly having a screw including a screw head, a body portion including a screw head receiving device for receiving the screw head and a rod receiving device for receiving a rod therein, the rod receiving device being offset from the screw head receiving device, and a locking device for locking a rod within the rod receiving device. A medical device for fixing a screw and a rod, the assembly having a screw including a screw head, a body portion having a receiver for receiving the screw head and an offset slot for receiving a rod therein, and a lock for locking the rod within the assembly. A receiving member for receiving and maintaining a rod therein, the receiving member having a body portion having a receiver for receiving a screw head and an offset slot for receiving a rod therein. A rod receiving device having a body portion having a receiver for receiving a screw therein and a rod seat offset within the body portion.

Abstract: An artificial intervertebral disc comprising at least two individual disc units that create a single center of rotation within an intervertebral space. An artificial intervertebral disc including housing members including spaced inner surfaces facing each other and oppositely facing outer surfaces for engaging spaced apart intervertebral surfaces; self-adjusting bearing mechanisms operatively disposed between the inner surfaces for moving relative to the housing members to adjust and compensate for vertebral disc motion; and a flange formed on an outer surface of said housing members for aligning the disc in an intervertebral space. A method for posteriorly inserting an artificial disc assembly by inserting at least two artificial disc assemblies around a spine and into an intervertebral space.

Abstract: An artificial intervertebral disc including housing members including spaced inner surfaces facing each other and oppositely facing outer surfaces for engaging spaced apart intervertebral surfaces; self-adjusting bearing mechanisms operatively disposed between the inner surfaces for moving relative to the housing members to adjust and compensate for vertebral disc motion; and positioning ring for controlling motion and position of the bearing mechanisms and for absorption of compressive loads. An artificial intervertebral disc including housing members having an oval recess on the inner surfaces; oval bearing mechanisms operatively disposed within the oval recess between the inner surfaces for moving relative to the housing members to adjust and compensate for vertebral disc motion; and oval positioning ring. A spring member for an artificial intervertebral disc including a substantially annular body having an axially extended bore therethrough defining a passageway.