A fixation device includes a tapered cannula defining a bore therethrough, a shaft, and a post. The shaft includes a proximal portion disposed within the bore, and central and distal portions extending distally from the tapered cannula. The proximal portion includes a threaded inner surface defined therein. The shaft includes blades disposed within the central portion, the blades movable between a closed position in which the blades are disposed within the shaft and an open position in which the blades extend laterally through the shaft. The post includes a threaded outer surface threadingly engaged with the threaded inner surface of the shaft. The post is movable longitudinally within the shaft to transition the blades between the closed and open positions.

A transpedicular anchoring screw including a screw body having a first helical thread having:includes a proximal portion, having notched portions inscribed within notched angular sectors and separated by separation portions inscribed within separation angular sectors, where, over a screw pitch, a ratio between the sum of the measurements of the separation angular sectors and the sum of the measurements of the notched angular sectors is between 50% and 150%. The anchoring screw also includes a distal portion, having notched portions inscribed within notched angular sectors and separated by separation distal portions inscribed within separation angular sectors, where, over a screw pitch, a ratio between the sum of the measurements of the separation angular sectors and the sum of the measurements of the notched angular sectors is between 0% and 10%.

A surgical screw configured to expand and prevent or minimize bone growth inside of the surgical screw is provided. Accordingly, the surgical screw is configured to increase the purchase of the surgical screw with respect to the bone, but also to be withdrawn from the bone without damaging the bone as a result of bone ingrowth. The surgical screw includes a center post with an inner bore and an outer sleeve concentric to the center post. An outer surface of the outer sleeve includes a thread to engage bone. The outer sleeve includes a cut pattern defining an expandable region configurable between a first state with a first radius measured from a longitudinal axis of the surgical screw to the outer surface and a second state having a second radius measured from the longitudinal axis to the outer surface.

A compression device made of a superelastic material having a peripheral portion with an upper surface, a lower surface, and a central opening extending therethrough is provided. One or more resilient teeth project inward of the peripheral portion into the central opening and are configured to exert a biasing force in an axial direction when deformed in a direction opposite the axial direction.

A surgical screw configured to expand and prevent or minimize bone growth inside of the surgical screw is provided. Accordingly, the surgical screw is configured to increase the purchase of the surgical screw with respect to the bone, but also to be withdrawn from the bone without damaging the bone as a result of bone ingrowth. The surgical screw includes a center post with an inner bore and an outer sleeve concentric to the center post. An outer surface of the outer sleeve includes a thread to engage bone. The outer sleeve includes a cut pattern defining an expandable region configurable between a first state with a first radius measured from a longitudinal axis of the surgical screw to the outer surface and a second state having a second radius measured from the longitudinal axis to the outer surface.

Disclosed herein are an implant with an attachment feature and a method for attaching to the same. The implant may include a cavity with a porous layer disposed within a non-porous layer wherein the non-porous layer defines a chamber. The chamber may receive and confine liquefiable material and direct liquefiable material to permeate through the porous layer. A method of attaching a device to the implant may include liquefying a liquefiable portion of the device and allowing the liquefied material to interdigitate with the second layer and then solidify to prevent pullout.

The invention relates to a screw (1), preferably a bone screw, comprising a shaft (2) with a tip (3), a head (4) and a thread (5). The shaft further comprises a longitudinal axis (A). An array of radial cross-sectional surfaces (Q) of the head (4) extend through the longitudinal axis (A) of the screw (1), the location of each radial cross-sectional surface (Q) being defined by an azimuth angle (6) in a plane (E) perpendicular to the longitudinal axis (A). Each radial cross-sectional area (Q) has an area defined by the longitudinal axis (A) and the outer surface of the screw (8). The thread (5) extends into the head (4) in such a way that the surface areas of the radial cross-sectional surfaces (Q′) in a first azimuth angle range (9) are constant and the surface areas of the radial cross-sectional surfaces (Q″) in a second azimuth angle range (10), which is different from the first, have a different, preferably smaller, value than the surface areas in the first azimuth angle range (9). The first azimuth angle range (9) is at most 350°, preferably at most 345°.

An implant may include a body having a first portion and a second portion and a structural member having a central member curve. In addition, the structural member may be exposed on an outer surface of the implant. Further, the central member curve may include a winding segment, and the winding segment of the central member curve may wind around a fixed path extending from the first portion of the body to the second portion of the body. Also, the central member curve may make one or more full turns around the fixed path. And, the structural member may have a member diameter at the winding segment, wherein the winding segment has a winding diameter corresponding with the full turn around the fixed path and the member diameter is greater than the winding diameter.

An intramedullary bone fixation device that includes a shaft with a flexible region. The flexible region may be configured to flex from a first shape to a second shape as the shaft moves along a curved medullary canal. For example, the bone fixation device may include a distal bone screw that is configured to move along the curved medullary canal of first and second segments of a fractured bone (e.g., two segments of a broken rib) and fasten to the segment bone segment. The bone fixation device may include a locking member (e.g., a proximal bone screw) that is configured to lock the shaft to the first bone segment. For example, the shaft may be fixed to the distal bone screw and ratchetably coupled to the shaft such that the first and second bone segments can be compressed together by urging together the distal bone screw and the locking member.

A device for fixation of inner and outer bone fragments comprises at least three fixation means (5), at least one tilting preventing means (6) and a securing plate (7). The fixation means (5) are configured to allow, during secondary compression of the inner and outer bone fragments (2, 3), a sliding movement of the fixation means and said outer bone fragment relative to one another and thereby an interruption of an engagement of the securing plate (7) with the outer bone fragment (3) without affecting the angular position of the fixation means relative to the securing plate and relative to one another. The tilting preventing means (6) is configured to allow, during said secondary compression, a sliding movement of the at least one tilting preventing means and said outer bone fragment (3) relative to one another and thereby an interruption of the engagement of the securing plate (7) with the outer bone fragment. The tilting preventing means (6) is also configured to prevent or counteract tilting of the device.