Abstract: A method of manufacturing an intervertebral disc prosthesis for insertion into an intervertebral disc compartment between two vertebra includes: a) biometrically determining the shape of a first dome formed within an apophyseal ring of the first vertebra; and b) providing a first constituent element which is provided on one side with a first joint member and has on the other side a first abutment face which abuts against the first vertebra when the intervertebral disc prosthesis is inserted into the intervertebral disc compartment. The first abutment face has a shape that has no rotational symmetry and that has a vertex configured such that the first constituent element can rotate within the first dome by at least 10° when the vertex of the first abutment face contacts a vertex of the dome.

Abstract: An intervertebral implant has a head positioned at one end of the implant. The head has a conical portion, on which an external thread is formed, and an outer end region formed by a protective elevation. The elevation is, is viewed from the outside, convexly curved and free from sharp edges. A central portion is positioned between the head and a basic structure which is formed at an opposite end of the implant. The central portion is formed by a plurality of struts extending from the head to the basic structure. The central portion is provided with an external thread and has openings formed between the head, the struts and the basic structure.

Abstract: The invention relates to a preparation device for preparing an intervertebral disc compartment (14) which is delimited by a first and a second vertebra (16, 18). Such a preparation is carried out prior to the insertion of an intervertebral disc prosthesis (110), in order to guarantee a correct positioning of the intervertebral disc prosthesis between the vertebrae (16, 18). The preparation device (10) comprises a reference frame (22), which is capable of being fastened above an operating table (12), and a first fixing element (58) which is capable of being rigidly connected to the first vertebra (16) are capable of being fastened to the reference frame (22) in varying first positions. A second fixing element (68) is capable of being rigidly connected to the second vertebra (18) and capable of being fastened to the reference frame (22) in varying second positions. A material-abrading tool (78) is capable of being fastened to the reference frame (22), preferably in varying positions.

Abstract: A method of manufacturing an intervertebral disc prosthesis for insertion into an intervertebral disc compartment between two vertebra includes: a) biometrically determining the shape of a first dome formed within an apophyseal ring of the first vertebra; and b) providing a first constituent element which is provided on one side with a first joint member and has on the other side a first abutment face which abuts against the first vertebra when the intervertebral disc prosthesis is inserted into the intervertebral disc compartment. The first abutment face has a shape that has no rotational symmetry and that has a vertex configured such that the first constituent element can rotate within the first dome by at least 10° when the vertex of the first abutment face contacts a vertex of the dome.

Abstract: A method of removing an intervertebral disc prosthesis from an intervertebral disc space includes the steps of: a) providing a surgical extractor with two legs; b) individually inserting the legs, while the legs are completely detached from each other, into the intervertebral disc space; c) rotating the legs so that they take up a locking position in which a pulling force can be applied by the legs to the intervertebral disc prosthesis; d) connecting the legs to an extraction element; and e) pulling at the extraction element so that the legs apply a pulling force to the intervertebral disc prosthesis.

Abstract: An intervertebral-disc prosthesis for insertion into an intervertebral disc compartment has a first and a second constituent element (10,10?) each being provided on one side with a joint member (28,28?) and on the other side with an abutment face which abuts against adjacent vertebrae. The abutment faces have a convexly curved region that has at least substantially the shape of a ramp. Preferably the region is surrounded by an annular flat region having a larger roughness than the curved region. The curved region may have a vertex which contacts a vertex of a dome formed in the adjacent vertebra. This facilitates rotation of the constituent element within the intervertebral disc compartment.

Abstract: An instrument for measuring the distraction pressure between vertebral bodies comprises a control device (34, 36; 64, 66) for introducing a pressure force onto surfaces of opposing vertebral bodies and a measuring device (50; 84) associated with the control device (34, 36; 64, 66) for determining the pressure force applied onto the vertebral bodies. According to the invention, at least one end region of the control device (34, 36; 64, 66) carries a support body (10), which is designed for engaging in a concave dome that is surrounded by a bone ring of the vertebral bodies. The support body can be pivoted about at least one pivoting axis with respect to the control device and/or has a convex support surface, so that the support body when engaging into the dome can be pivoted in a sliding manner with respect to the vertebral body about at least one pivoting axis.

Abstract: A system for aligning a material-abrading tool (56, 58) relative to an intervertebral-disc compartment at the start of an intervertebral-disc operation comprises an operating table (12), which is capable of being tilted about its longitudinal axis (14), and an image-recording device (22) for recording lateral images of the intervertebral-disc compartment. The tool (56, 58) is capable of being fastened to a reference frame (20), which is arranged above the operating table (12), in a defined relative position with respect to the reference frame (20). Farthermore, the reference frame (20) is capable of being tilted about a tilt axis parallel to the longitudinal axis (14) of the operating table (12). The system comprises, in addition, an alignment element (30) which is rigidly connected to the reference frame (20) and at the same time capable of being registered with the intervertebral-disc compartment by the image-recording device (22).

Abstract: Disclosed is a surgical extractor (20) for surgically removing intervertebral prostheses that are provided with two support plates (3, 4) with one respective joint part (5, 6). The inventive extractor (20) comprises two legs (21, 21?) which are interconnected in a prong-shaped manner, can be inserted into an intermediate space between the two support plates (3, 4), and each support at least one locking element (22, 22?) at the free end thereof. Said at least one locking element (22, 22) allows for insertion into the intermediate space between the two support plates (3,4) in a first position while protruding from the intermediate space in a vertical direction in a second, locked position. The two legs (21, 21?) are connected to a common extraction means (24, 25, 26) for transmitting a tractive power to the legs (21, 21?) in the longitudinal direction thereof.

Abstract: An intervertebral-disc prosthesis for insertion into an intervertebral disc compartment has a first and a second constituent element (10,10?) each being provided on one side with a joint member (28,28?) and on the other side with an abutment face which abuts against adjacent vertebrae. The abutment faces have a convexly curved region that has at least substantially the shape of a ramp. Preferably the region is surrounded by an annular flat region having a larger roughness than the curved region. The curved region may have a vertex which contacts a vertex of a dome formed in the adjacent vertebra. This facilitates rotation of the constituent element within the intervertebral disc compartment.

Abstract: The invention relates to a preparation device for preparing an intervertebral disc compartment (14) which is delimited by a first and a second vertebra (16, 18). Such a preparation is carried out prior to the insertion of an intervertebral disc prosthesis (110), in order to guarantee a correct positioning of the intervertebral disc prosthesis between the vertebrae (16, 18). The preparation device (10) comprises a reference frame (22), which is capable of being fastened above an operating table (12), and a first fixing element (58) which is capable of being rigidly connected to the first vertebra (16) are capable of being fastened to the reference frame (22) in varying first positions. A second fixing element (68) is capable of being rigidly connected to the second vertebra (18) and capable of being fastened to the reference frame (22) in varying second positions. A material-abrading tool (78) is capable of being fastened to the reference frame (22), preferably in varying positions.