A prosthesis for replacing a joint between a first bone and a second bone in a human hand or foot includes first and second rigid blocks (110, 120) interconnected by a flexible bridging structure (130). In certain embodiments, the flexible bridging structure employs a helical spring oriented with its central axis aligned with a central axis of a bone anchor portion of the first rigid block. One or more shear-limiting element (101, 140) is deployed within an internal volume of the helical spring (130) to limit an extent of shear deformation applied to the helical spring. Other aspects of the invention relate to adjustable bone-abutment flanges, an alternative bridging structure employing a helically-twisted leaf spring, and a structure and method for bridging between the first metacarpal and the scaphoid in case of removal of the trapezium from the hand.

The invention relates to an arthrodesis plate for the stiffening of joints, in particular finger joints, comprising a proximal and distal anchoring region which are connected to one another in a mechanically rigid manner, characterised in that at least one outer contour of one of the two anchoring regions has a cross-section which is undulating, for example roof-shaped, or is provided with alternating crests and troughs by means of coating, and/or has a transversal-sagittal cross-section.

A surgical implant having a plastic (e.g., PEEK) component having an exposed surface, wherein at least a portion of the exposed surface has a plurality of parallel microgrooves that (i) enhance bone growth and osseointegration with adjacent bone and, after the osseointegration, (ii) increase pull-out force of the surgical implant from the adjacent bone. In certain embodiments, the microgrooves have widths of less than or equal to 12 micrometers, depths of less than or equal to 12 micrometers, crests of less than or equal to 12 micrometers, and a periodicity of less than or equal to 24 micrometers.

Disclosed is a device for assisting in the placement of a trapeziometacarpal prosthesis including a cup to be fixed in the trapezium of a patient and a stem to be fixed in the patient's first metacarpal. The device includes a first guide to be interposed between the trapezium and the first metacarpal, the first guide including a first body having a first surface to be positioned on the articular surface of the trapezium, the first surface congruent with the articular surface of the trapezium and a second surface to face the articular surface of the first metacarpal before resection, the second surface preferably being congruent with the articular surface of the first metacarpal so as to be positionable on the articular surface of the first metacarpal. The first guide also includes locating members carried by the first body and arranged to define resection lines for the first metacarpal.

Implants, instruments, and methods are presented for fixing adjacent bone portions to promote fusion of the bone portions.

Arthroplasty implants replace an articulating surface of a bone joint such as bone joints of the foot, and is characterized by a three-component device comprising a bone screw, a button, and a cap. The button incorporates knurling on its distal end to fixate onto bone, a center hole, a spherical pocket to mate with the bone screw for stabilization, and a proximal retention structure to mate with the cap. The bone screw incorporates distal bone (cortical) threads or threading, a spherical head, and a drive structure used to insert the bone screw through the hole of the button and into the bone (e.g. a distal segment of the first metatarsal). The cap incorporates a distal mating structure that retains the cap onto the button, a proximal smooth spherical head that mates with the distal surface of the bone (e.g. a phalange bone), and a tang that prevents rotation after implantation.

A sling suspension system for supporting the thumb of a patient after basal joint arthroplasty, the sling suspension system comprising: an index metacarpal anchor, a thumb metacarpal anchor and a sling for securing the thumb metacarpal anchor to the index metacarpal anchor; the index metacarpal anchor comprising at least one bone-engaging element for engaging the index metacarpal and a sling-engaging element for capturing the sling to the index metacarpal anchor; the thumb metacarpal anchor comprising at least one bone-engaging element for engaging the thumb metacarpal and a sling-engaging element for capturing the sling to the thumb metacarpal anchor; and the sling comprising an elongated body having a first anchor-engaging element for securing the sling to the sling-engaging element of the index metacarpal anchor, and a second anchor-engaging element for securing the sling to the sling-engaging element of the thumb metacarpal anchor, wherein the second anchor-engaging element is adjustable.

A device, for example a medical implant, and a method of making the same, the device having a metal or metal alloy substrate, for example cobalt chrome, and a diffusion hardened metallic surface, for example a plasma carburized surface, contacting a non-diffusion hardened surface or a diffusion hardened surface having a diffusion hardening species different from that of the opposing surface.

An implant couples a first bone of a hand to a second bone of the hand. The implant includes a body that defines a median plane. The body also defines a first joint surface having a first central region that articulates with the first bone. The body further defines a second joint surface having a second central region that articulates with the second bone, and the second central region is disposed on an opposite side of the median plane of the body relative to the first central region. The first and second central regions correspond to profiles of first and second axial segments, respectively, the first and second axial segments are each one of a cylinder, a cone and a torus and are centered on first and second axes, respectively, and the first and second axes, as projected on the median plane, are substantially perpendicular to each other.