Abstract: A polyaxial connector for spinal fixation systems has a lateral connector element having a first receptacle for a polyaxial connection to a spherical head of a pedicle screw and a second receptacle for a polyaxial connection to a spherical head of tulip that is configured to receive a connection rod clamped in the tulip by a locking element. A clamping piece is mounted in longitudinally-movable manner in the connector element between the receptacles. If the locking element is tightened, a pressure ram received in the tulip exerts a clamping force on the pedicle screw head, thereby fixing the connector element to the pedicle screw.

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 computer program for spine mobility simulation is configured, if running on a computer, to cause the computer to perform the following steps: a) accessing bio-metric data which relate to the spine of a patient, the spine having at least one compromised spine segment; b) displaying a model of the spine of the patient comprising a plurality of vertebrae; c) enabling a user to change the position of at least one of the vertebrae of the spine model; d) computing the effects of the position change on the remaining vertebrae; e) displaying the spine model in a new configuration, thereby taking into account the position changed by the user in step c) and the position changes of the remaining vertebrae computed in step d).

Abstract: A spine fixation system (10) comprises a rod (12a, 12b), which is configured to extend over a portion of the spine, a plurality of fasteners (14) and a plurality of connectors (18). Each fastener has a longitudinal axis (22) and is configured to be secured to a vertebra (V1, V2, V3) to be treated. Each connector (18) is connected to, or is capable of being connected to, one of the fasteners (14) and has a seat member (20) for receiving and fixing the rod (12a, 12b). The seat member (20) is capable of being fixed in different rotational positions with regard to a rotational axis (46) that extends, or is capable of being positioned such that it extends, parallel to but not coinciding with the longitudinal axis (22) of the fastener (14) to which the respective connector (18) is connected.

Abstract: A spine fixation system (10; 210; 310) comprises a first rod (16; 216) that connects a first vertebra (V2) to a second vertebra (V) but not to a third vertebra (V4), and a second rod (14; 214) that connects the second vertebra (V3) to the third vertebra (V4) but not to the first vertebra. The spine fixation system is configured such that first vertebra (V2), but not the third vertebra (V4), is allowed to move relative to the second (V3) vertebra after the spine fixation system has been completely implanted.

Abstract: An instrument set for screwing an implant into an intervertebral disc space comprises a guide sleeve and a screwing-in instrument. The latter has a shank having a distal end at which the implant can be fixed in a rotationally rigid manner. At the proximal end a rotary handle is fastened in a rotationally rigid manner. The screwing-in instrument further has a residual-advance indicator, which is configured to quantitatively indicate to the surgeon, during the screwing-in procedure, how far the implant is distant in the axial direction from an axial specified position that is fixed relative to the location at which the guide sleeve is supported on the vertebrae.

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-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.