A segmented disc nucleus replacement prosthesis and system for its implantation wherein the segments are made of a compliant, homogeneous material throughout. The prosthesis comprises a plurality of modular segments that mate together in a rail-and-slot arrangement. The rails and slots are configured to interlock and hold together under load despite being formed of compliant materials. In one embodiment, insertion tools and stabilizers are utilized for manipulation of the modular segments, the insertion tools and stabilizers being designed to accommodate for handling the compliant modular segments.

An expanding implant (10, 10, 10) includes a base (12) having a contact surface (14) for contacting a first region of tissue and a displaceable portion. (24) having a contact surface (26) for contacting a second region of tissue. The base (12) has a proximal portion (16) in sliding engagement with, a distal portion (18) so as to define an arcuate path of relative motion between the proximal and distal portions. The base assumes an initial state with a first arcuate extent and is adjustable towards a second State by changing an: extent of overlap between the proximal and distal portions to vary an. arcuate extent of the base. First and second rigid linking segments (20, 22) are in articulating connection with the distal and proximal portions of the base, and with the displaceable portion such that adjustment of the base from the initial state towards the second state causes an increase in a distance between the contact surfaces of the base and the displaceable portion.

Tissue spacer implants and surgical methods for inserting the implants are disclosed. The implants may include a first cylindrical body with an outer surface, an axially extending hole, and a first end, a second cylindrical body with an outer surface and an axially extending hole, and an adjustment member with an outer surface, an axial hole, and at least one helical slot. The adjustment member axial hole may be adapted to receive the first cylindrical body and the adjustment member may be configured to be inserted into the axially extending hole of second cylindrical body. The implants may also include a travel mechanism for engaging the first cylindrical body, adjustment member, and second cylindrical body along the at least one helical slot to maintain a space between two bodies of tissue.

A disc prosthesis comprising an upper cover provided with a cavity and a curved surface; a bearing member comprising an outer surface, on which the upper cover can rotate and received by the cavity, and at least one mount; a movement member which is provided with an outer surface compatible with an inner surface of the mount, and which is received by the mount so as to move concurrently with the upper cover; a lower cover provided with a cavity to receive said mount and a curved surface; and a connection member extending from the cavity towards the lower cover and being mounted to the movement member by being passed through a channel which extends along the bearing member and is in connection with said mount so as to connect the bearing member to the upper cover.

The present invention relates to an intervertebral disc prosthesis preferably comprising at least three pieces including an upper plate (1), a lower plate (2) and a mobile core (3) at least in relation to the lower plate (2), co-operation means (23, 33) allowing to limit or eliminate the movements of the core (3) in relation to the lower plate (2), in translation and in rotation, respectively, about an axis substantially parallel to the lower plate (2) and about an axis substantially perpendicular to the lower plate (2), at least one part of the surface of at least one plate being concave and complementary with a convex surface (30) of the core (3), with which it is in contact, wherein the tip (31) of the convex surface (30) of the core (3) is off centre, in at least one direction, in relation to the centre (32) of this convex surface (30).

An intervertebral prosthetic implant having a first endplate having a first surface configured to substantially engage with a first vertebral body and a second surface having an extension with a concave contact surface, the concave contact surface being spaced apart from the second surface. A second endplate is provided with a first surface configured to substantially engage with a second vertebral body and a second surface comprising a convex contact surface, and the second endplate having a securing element positioned along and above the second surface defining a first and second window on opposing sides of the second surface. The securing element extends along the width and length of the lower endplate and configured with an access hole. An extension portion extends from the first surface of the first endplate through the access hole of the securing element and contacts the second surface of the second endplate.

An orthopaedic fixation assembly for prosthetic biologic attachment. The orthopaedic fixation assembly may include a main body with a longitudinally-extending stem having a proximal end, a distal end, and a cavity body. An anchor plug may be configured to be received within the stem cavity, and securable thereto via complementary mating surfaces. A spindle structure may be fixedly attached to the proximal end of the longitudinally-extending stem and protrude outwardly therefrom such that a portion of the structure extends externally beyond the resected cavity of the bone that may prevent rotational motion of the spindle. The spindle structure may have at least one compliant biasing member configured to apply a compressive force to the surrounding bone. A porous coating may be at the juncture between stem and spindle structure, on the spindle, and the splines and anti-rotation chocks, improving the initial stability of the implant and facilitating long-term bone ingrowth.

Tissue spacer implants and surgical methods for inserting the implants are disclosed. The implants may include a first cylindrical body with an outer surface, an axially extending hole, and a first end, a second cylindrical body with an outer surface and an axially extending hole, and an adjustment member with an outer surface, an axial hole, and at least one helical slot. The adjustment member axial hole may be adapted to receive the first cylindrical body and the adjustment member may be configured to be inserted into the axially extending hole of second cylindrical body. The implants may also include a travel mechanism for engaging the first cylindrical body, adjustment member, and second cylindrical body along the at least one helical slot to maintain a space between two bodies of tissue.

An expandable implant is disclosed having an adjustable height for insertion between two adjacent bony structures or joint surfaces, for example between two adjacent spinal vertebrae. The implant includes at least one gear associated with at least one threaded shaft. Rotation of the gear engages the threaded shaft to expand the implant. The implant can be inserted in a collapsed configuration and expanded in situ. The invention also provides methods for using the implant to facilitate arthrodesis or fusion of adjacent joint surfaces or spinal vertebrae.

The present application relates to a facet joint prosthesis comprising a first component having a first disc with a first outer face for engagement of a first bone. The first outer face has an opposed first inner face, which includes a first post connecting said first disc to a tongue. The facet joint prosthesis further comprises a second component having a second disc with a second outer surface for engagement with a second bone. The second outer surface has an opposed second inner face, which comprises a bridge located near the periphery of said second disc. Said bridge connects the second disc with a third disc. The third disc comprises a pocket. Insertion of said tongue into said pocket and rotation of said tongue relative to said pocket results in a locking of said tongue between said second disc and said third disc.