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 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.

An array stabilizer for a surgical system includes a pair of arms configured to extend alongside opposite sides of a portion of an array adapter, which is attachable to a rotational instrument in a manner such that the rotational instrument is rotatable about a central axis relative to the array adapter. The array adapter is configured to extend from another component of the surgical system, such that at least one of the arms of the array adapter is configured to resist rotation of the array adapter about the central axis relative to such component as the rotational instrument rotates. The array stabilizer is either rigidly integrated with such component or is coupled to such component via a coupling device.

Disclosed are bone screw drill targeting guides and methods for using such targeting guides that are useful in surgical procedures for correcting hallux valgus deformity.

Disclosed are bone screw drill targeting guides and methods for using such targeting guides that are useful in surgical procedures for correcting hallux valgus deformity.

Disclosed is a system to engage one or more tools. In the system, a drive shaft and collet may be assembled to engage and disengage, selectively, a plurality of tools. A guide may be used with the system to select various features of a procedure, such as depth and position.

Disclosed is a system to engage one or more tools. In the system, a drive shaft and collet may be assembled to engage and disengage, selectively, a plurality of tools. A guide may be used with the system to select various features of a procedure, such as depth and position.

A method of preparing a knee joint for a prosthesis in a patient includes mating a patient-specific three-dimensional curved inner surface of a femoral alignment guide onto a corresponding three-dimensional femoral joint surface of the patient. The patient-specific three-dimensional curved inner surface is preoperatively configured from medical scans of the knee joint of the patient. First and second holes are drilled into an anterior portion of the femoral joint surface through corresponding first and second guiding apertures of the femoral alignment guide.

A stemless humeral head replacement system including a base plate and a humeral head implant. The base plate includes a bone facing side, an implant side opposite the bone facing side, a curvate perimeter, at least one fin protruding from the bone facing side a first distance and extending linearly a length along the bone facing side, and an implant engagement structure on the implant side. The humeral head implant includes a curvate implant surface and a base plate engagement structure opposite the curvate implant surface, the base plate engagement structure configured to couple to the implant engagement structure of the base plate.

A tibial alignment device includes an upper part for coupling with a tibial cutting guide and a lower part coupled to the upper part to be vertically slidable, wherein the upper part includes a cutting guide coupling part configured to mount the tibial cutting guide, and a connection part to connect the upper part and the lower part, and the lower part includes an ankle forceps part, wherein the cutting guide coupling part includes a fastening member for coupling to the tibial cutting guide, and a reception member to slidably receive the fastening member, wherein the fastening member includes a coupling part that protrudes to be coupled to the tibial cutting guide, the reception member includes a coupling part that protrudes to be coupled to the tibial cutting guide, and the coupling part of the fastening member is capable of adjusting a gap with respect to the coupling part of the reception member.