An intervertebral implant may include a shaft having a proximal end, a distal end, a longitudinal axis, a minor diameter, and a helical thread disposed about the shaft along the longitudinal axis between the proximal end and the distal end of the shaft. The helical thread may include a major diameter and a concave undercut surface angled towards one of the proximal end and the distal end of the shaft. The intervertebral implant may be implanted within an intervertebral space between a superior vertebral body and an inferior vertebral body. A ratio of the major diameter to the minor diameter may be less than 1.50. The concave undercut surface may engage the superior vertebral body and the inferior vertebral body and may be shaped to resist at least one force transmitted between the superior vertebral body and the inferior vertebral body to stabilize the intervertebral space.

A bone disunion instrument system may include a first bone pin, a second bone pin, and a guide block. The guide block may include first and second bone pin holes to receive the first and second bone pins, and a window intermediate the first and second bone pin holes. The first bone pin may be anchored in a first bone portion and inserted through the first bone pin hole, and the second bone pin may be anchored in a second bone portion and inserted through the second bone pin hole to impart a compression or distraction force on a bone disunion between the first and second bone portions. The window formed through the guide block may provide access for an implant placed through the window to stabilize the bone disunion while the bone disunion is placed under a compression or distraction force.

A bone disunion fastener may include a fastener shaft, a helical thread, and a bone staple. The helical thread may include a concave undercut surface oriented towards one end of the fastener shaft. The bone staple may include a first bone-engaging feature, a second bone-engaging feature, and a middle portion with an opening. The bone disunion fastener may be implanted along a disunion between a first bone portion and a second bone portion. The concave undercut surface may be shaped to resist at least one force transmitted between the first bone portion and the second bone portion to stabilize the disunion. The first bone-engaging feature may engage the first bone portion and the second bone-engaging feature may engage the second bone portion to couple the bone staple to the bone portions and resist at least one force transmitted between the bone portions to stabilize the disunion.

The invention relates to a biodegradable, magnesium-containing bone screw for implanting into a patient body for use in medical applications, such as, orthopedic, craniofacial and cardiovascular surgery. The bone screw has a head, shaft and tip. The thickness of the head is greater than the thickness of conventional bone screws. The shaft includes both a non-threaded and a threaded portion. The tip is non-threaded and pointed, such as, conical in shape. The composition of the bone screws provide for improved biodegradability and biocompatibility, and the features of the structure of the bone screws facilitate guidance and placement during implantation as well as reduce the potential for mechanical failures.

A bone screw comprising a shaft having a wall, the wall including a minor diameter and at least one thread having an external thread form. The thread form including a first portion comprising a crest of the thread form and a second portion extends between a minor diameter of the thread form and the first portion. The first portion having a solid configuration relative to the second portion. In some embodiments, systems, spinal constructs, surgical instruments and methods are disclosed.

Monocortical pin (1) for an external fixator for temporary and/or permanent fixing applications for treating bone fractures and connecting two or more bone fragments together, comprising an elongated cylindrical stem (2) which extends along a longitudinal axis (X) and a conical portion (3) with a tip having an external thread for inserting the pin (1) inside a bone; where said elongated cylindrical stem (2) has a flattened surface (2a) which lies along a reference plane (A) parallel to the longitudinal axis (X) and said conical portion (3) with the tip has an overall length, measured along the longitudinal axis, equal to the diameter (d) of the stem (2) +20% of said diameter (d); said monocortical pin (1) is characterized in that the conical portion (3) comprises a tip (31) which has a centring zone (33) which extends longitudinally over a length equal to 6-8% of the diameter (d) of the stem (2), and a threaded portion (32); moreover the conical portion (3) comprises two base cones (3a and 3b) having two different angles of conicity, a first base cone (3a) in a distal position with respect to the elongated cylindrical stem (2) of the monocortical pin and a second base cone (3b) in a proximal position with respect to the elongated cylindrical stem (2) of the monocortical pin; said first base cone (3a) having an angle of conicity of 13°; said second base cone (3b) having an angle of conicity of 26°.

A bone fastener system can comprise a fastener and a first sizing component. The fastener can comprise a shaft that provides an anchoring footprint. The first sizing component can be configured to be connected to the shaft and can include a first anchoring feature, or circumferential bone engaging feature, to increase a size of the anchoring footprint. The first anchoring feature can comprise a sleeve that radially expands a diameter of the threaded shaft. The first anchoring feature can comprise axially extending teeth. The system can further comprise a second sizing component including a second anchoring feature to increase the size of the anchoring footprint, the second anchoring feature being different from the first anchoring feature. The second anchoring feature can expand the diameter of the threaded shaft a greater amount than the first anchoring feature. The second anchoring feature can have a length greater than the first anchoring feature.

Self-drilling, self-tapping and self-advancing orthopedic screws are provided. An orthopedic screw includes a relief cut at the tip of the screw that is timed to the distal-most thread at the end of the screw tip to create a wide and sharp cutting edge for the screw.

A spinal fixation device includes a modular head assembly and a bone screw having a head and a shank. The modular head assembly includes a housing defining proximal and distal surfaces and a throughhole therethrough; an anvil slidable within the throughhole; a biasing member circumferentially surrounding the anvil; an assembly cap secured to the housing and defining an inner surface having a first portion with a first diameter and a second portion with a second diameter smaller than the first diameter; a retaining ring movable from the first portion of the assembly cap to the second portion of the assembly cap to transition the retaining ring between a first configuration in which the retaining ring is sized to receive the head of the bone screw and a second configuration in which the retaining ring is compressed about the bone screw to fix the bone screw relative to the modular head assembly.

A minimally invasive precision cutting guide, targeting guide, implant, and other instruments comprise a system that permits a physician to surgically correct a bunion or similar deformity with a minimum disruption of surrounding soft tissue. The precision cutting guide ensures that the physician cuts bone in the proper location and orientation. Each of the instruments is designed to minimize disruption to surrounding soft tissue. The system also precisely locates an orthopedic implant such that it can fixate two bone fragments after an osteotomy, or two bones after surgery. The precision cutting guide, targeting guide, implant, and other instruments are provided in a sterile kit for the convenience of the surgeon and safety of the patient.