Provided is an artificial joint that can improve fatigue strength while achieving the ability to fix to a bone. An artificial joint 1 includes a stem portion 2. The stem portion 2 has a distal end for insertion into a bone and a proximal end opposite the distal end and includes a roughened surface portion 4 which is provided in a proximal end-side portion, which has a rougher surface than a distal end-side portion, and which is larger in cross-sectional area than the distal end-side portion. The roughened surface portion 4 includes a distal end-side edge section 7 and a proximal end-side section 7, the distal end-side edge section 7 including a distal end-side edge portion of the roughened surface portion 4, the proximal end-side section 7 being configured as a section closer to the proximal end than the distal end-side edge section 7 is to the proximal end. The distal end-side edge section 7 has a surface roughness Ra1 lower than a surface roughness Ra2, Ra3 of the proximal end-side section.

A short-stem femoral implant suitable for use in hip arthroplasty configured to self-stabilise against sliding across the endo-cortex when implanted in a subject's femur. The femoral implant includes a distal end configured to engage in abutment with the lateral endo-cortex of the subject's femur at two distal locations such that when implanted, the femoral implant has a reduced tendency for sliding across the endo-cortex.

A short-stem femoral implant suitable for use in hip arthroplasty configured to self-stabilise against sliding across the endo-cortex when implanted in a subject's femur. The femoral implant includes a distal end configured to engage in abutment with the lateral endo-cortex of the subject's femur at two distal locations such that when implanted, the femoral implant has a reduced tendency for sliding across the endo-cortex.

Hip implant systems described herein can include a distal stem, a proximal body, and a fastener. In some embodiments, the distal stem can include a cavity configured to receive the fastener when a portion of the distal stem is positioned within the proximal body. In some embodiments, the distal stem can include a threaded exterior surface configured to mate with a fastener when a portion of the distal stem is positioned within the proximal body. In some embodiments, a distal end of the distal stem can include an anterior relief configured to conform to interior surface of a femoral canal of a patient.

A hip/shoulder prosthesis includes: a head component; a metaphyseal component; a diaphyseal nail, and a locking device. The head component includes: a front face and rear face; with a bore, and first and second shaped recesses in the rear face. The metaphyseal component includes: a central transverse aperture at an angle to the metaphyseal component's axis; a first end configured for threaded engagement within the bore of the head component; and a longitudinal hole that begins at the second end, transects the transverse aperture and reaches the first end, to receive the locking device. The diaphyseal nail is inserted in the femoral or humeral canal, and includes: fastening apertures that receive corresponding screws for fastening the diaphyseal nail to the femur or humerus; a portion configured to he received within, and engage, the transverse aperture of the metaphyseal component, and a transverse hole configured to receive the locking device.

A hip implant for use in hip replacement surgical procedures. The hip implant comprises a femoral stem body designed for fixation in two planes, i.e. the AP plane and the lateral plane. The curvature of the implant is designed to mirror the geometry of the femur, thus providing for more contact points with the inner surface of the medullary cavity. The outer surface curvature cooperates with the inner surface associated with the medullary cavity. The hip implant is designed to provide increased or maximum contact with the interior of the bone, i.e. femur, while decreasing or minimizing stress risers or stress points, thus reducing the likelihood of patient pain and/or implant failure.

A method for manufacturing an implant includes pre-selecting a designed porous microstructure having a lattice composed of cells, including selecting one or more predetermined cell topologies, selecting a predetermined porosity, cell strut thickness and packing factor of the lattice, and selecting an arrangement of the cells within the lattice to have a periodic and/or aperiodic arrangement. Additive manufacturing is used to form the designed porous lattice microstructure in at least a region of at least an external surface of the implant.

An intramedullary stem prosthesis includes a trunnion tapered in a first direction toward a proximal end of the intramedullary stem, and a conical shaft interfacing with the trunnion at a modular taper junction. The conical shaft is tapered in a second direction toward a distal end of the second component and has a proximal portion, a distal portion, and flutes positioned about a longitudinal axis of the conical shaft and extending along an entire length of the conical shaft and terminating at the modular taper junction such that the flutes intersect the modular taper junction. The proximal portion defines a first taper angle, the distal portion defines a second taper angle greater than the first taper angle, and the flutes define a major diameter of the conical shaft. The major diameter tapers at a major diameter taper angle that is constant along the entire length of the conical shaft.

Provided is an artificial joint that improves fatigue strength and fixes to a bone. An artificial joint includes a stem portion having a distal end for insertion into a bone, a proximal end opposite the distal end, and a roughened surface portion provided in a proximal end-side portion, which has a rougher surface than a distal end-side portion, and which is larger in cross-sectional area than the distal end-side portion. The roughened surface portion includes a distal end-side edge section and a proximal end-side section, the distal end-side edge section including a distal end-side edge portion of the roughened surface portion, the proximal end-side section being configured as a section closer to the proximal end than the distal end-side edge section is to the proximal end. The distal end-side edge section has a surface roughness Ra1 lower than a surface roughness Ra2, Ra3 of the proximal end-side section.

An anchoring stem for a joint prosthesis with a centromedullary fixation includes a metaphyseal-diaphyseal (M-D) portion intended to be inserted into the medullary canal of the long bone of the joint to be prosthesized. It receives an epiphyseal-diaphyseal (E-D) portion, having its upper portion protruding from the considered bone and intended to receive in turn an articular element. The M-D portion and the E-D portion are independent from each other but may be fastened to each other. The E-D portion is received within the M-D portion along a direction parallel or substantially parallel to the main dimension of the M-D portion, along a length of cooperation of the portions with each other such that the ratio of the length of reception of the E-D portion within the M-D portion to the total length of the M-D portion is in the range from 0.5 to 0.85. The M-D portion is provided with means capable of forbidding any rotation or angular displacement of the E-D portion once the latter has been received within the M-D portion.