258 results about "Femoral stem" patented technology

It is an object of the present invention to provide an improved orthopedic implant system with satisfied biological, mechanical and morphological compatibilities.Solid metal femoral stem and solid metal acetabular head are covered with diffusion-bonded foamed-shaped sheet made of commercially pure titanium or titanium alloy(s). The open-cells in said foamed metal sheet are impregnated with biocompatible polymethyl methacrylate resin cement, which is reinforced with selected oxides including alumina, magnesia, zirconia, or a combination of these oxides along with an application of a small amount of a metal primer agent.

The present invention provides a femoral component, and a method for surgical implantation of a femoral prosthesis, comprised of a revision knee implant and corresponding cutting block system. In particular, the revision knee implant, comprised of a femoral component having incremental markings thereon and a femoral stem, and corresponding cutting block system having corresponding incremental markings thereon, enables a surgeon maximally to position the cutting block adjacent as much area as possible of a distal femur of a patient and to infinitely position the femoral component in the exact position indicated by the cutting block.

It is an object of the present invention to provide an improved orthopedic implant system with satisfied biological, mechanical and morphological compatibilities. Solid metal femoral stem (entirely or partially) and solid metal acetabular head (entirely or partially) are covered with diffusion-bonded foamed-shaped sheet made of commercially pure titanium or titanium alloy(s). The open-cells in said foamed metal sheet are impregnated with biocompatible polymethyl methacrylate resin cement, which is reinforced with selected oxides (e.g., alumina, magnesia, zirconia, or a combination of these oxides) along with an application of a small amount of a metal primer agent.

Apparatus and method are described for interoperatively determining, during a trailing procedure conducted in connection with total hip arthroplasty, a combination of neck length and femoral head offset required in a femoral component for establishing appropriate hip mechanics in a prosthetic hip joint to be implanted at an implant site. A trial femoral head is coupled for selective movement relative to a femoral stem component to move the trial femoral head longitudinally and laterally relative to a predetermined direction among selected combinations of trial distance and trial offset to evaluate hip mechanics and determine interoperatively an appropriate combination of trial distance and trial offset corresponding to the combination of neck length and femoral head offset required in the prosthetic hip joint.

Bipolar prostheses which include various structures and other techniques for optimizing material wear and mechanical strength properties. Such prostheses feature, for example, improved resistance to polyethylene wear while also reducing potential for dislocation of the femoral stem from the prosthesis. Such techniques and structures include varying wear resistance and mechanical strength treatment in various components of the prostheses or portions of those components as desired to improve, accentuate or optimize wear performance and dislocation reduction, locking ring structural features, structures for retaining locking rings in the bipolar prosthesis shell, and structures for limiting or reducing movement or rotation of locking rings and liners in bipolar prosthesis shells.

A method and apparatus for performing a minimally invasive total hip arthroplasty. An approximately 3.75-5 centimeter (1.5-2 inch) anterior incision is made in line with the femoral neck. The femoral neck is severed from the femoral shaft and removed through the anterior incision. The acetabulum is prepared for receiving an acetabular cup through the anterior incision and the acetabular cup is placed into the acetabulum through the anterior incision. A posterior incision of approximately 2-3 centimeters (0.8-1.2 inches) is generally aligned with the axis of the femoral shaft and provides access to the femoral shaft. Preparation of the femoral shaft including the reaming and rasping thereof is performed through the posterior incision, and the femoral stem is inserted through the posterior incision for implantation in the femur. A variety of novel instruments including an osteotomy guide an awl for locating a posterior incision aligned with the axis of the femoral shaft, a tubular posterior retracter, a selectively lockable rasp handle with an engagement guide; and a selectively lockabele provisional neck are utilized to perform the total hip arthroplasty of the current invention.

A modular hip prosthesis includes a femoral stem, a spherical head and a coupling member extending from the head defining a neck whose lower end forms a base which plugs into a socket at the top of the stem to form a tapered neck / stem junction. That junction is aligned with the stem axis and has a cross-section with opposite sides that extend generally parallel to the sides of the stem. With such an arrangement, that junction may be relatively long and have a relatively large cross-sectional area thus making a strong junction even in smaller femoral implants.

A femoral stem for canines or humans is made bone-compliant by use of a thick sintered titanium body in a proximal bone contacting region and a polymeric or ceramic body in a distal bone contacting region of the femoral stem. An elastic modulus is thereby engineered to match that of bone tissue. The porous sintered titanium body is created by sintering spheres of titanium. It is bonded to a central solid biocompatible metallic body by diffusion bonding. The distal region has a biocompatible polymeric body or biocompatible cement body. When compression molded the distal region develops an elastic modulus matching that of bone tissue. The proximal region has a porosity designed to encourage bone ingrowth.

Methods and apparatus for orthopedic replacement of the hip through three incisions with a modular prosthetic system assembled in vivo while substantially preserving muscles and soft tissues around the hip joint resulting in reduced healing time and decreased risk of dislocation. A prosthetic femoral stem is inserted into the femur. A prosthetic femoral neck is inserted from a point along the side of the patient's body and into the side of the femur and through a lateral bore in the prosthetic femoral stem to join the prosthetic femoral head. The methods and apparatus include structures and techniques for fixing or enhancing interconnection of implant components, such as by increasing the interconnection in an interference fit with one or more tapers, threads, and / or cooling of components prior to assembly.

Disclosed are a femoral stem for artificial coxal articulation, in which portions of the femoral stem interfering with and contacting an insertion in the joint movement of the femoral stem are removed from the femoral stem so as to maximize the range of the joint movement thereof while maintaining the cross sectional area thereof, and a method for processing a neck portion of the femoral stem. The method includes cutting symmetrical portions of the outer circle of a circular rod to form cutting planes inwardly inclined such that the cutting planes contact a virtual inner circle having the same center as that of the outer circle; and rounding a portion between the cutting planes along the inner circle so that the inner part of the outer circle is shorter than the outer part of the outer circle.

The present disclosure relates to bone plates that are configured for use with bones having periprosthetic fractures. For example, in the event that a proximal femur is fractured in an area that is adjacent to a prosthetic component, such as a femoral stem used in a hip replacement, the periprosthetic bone plates of the present invention may be used. In one exemplary embodiment, the periprosthetic bone plates include a periprosthetic zone having a plurality of central apertures and a plurality of outer apertures that are offset from the central apertures. The periprosthetic zone may further include a plurality of indentations, each indentation extending longitudinally between adjacent outer apertures to narrow a width of the bone plate.

Hip replacement prosthesis are provided, comprising a femoral stem, a femoral head coupled to the femoral stem, and an acetabular assembly coupled to the femoral head, and a plurality of sensors coupled to at least of the femoral stem, femoral head, and acetabular assembly.

A canine femoral stem system provides a set of sizes of stems designed to fit in a reamed femoral bone canal with controlled interference. The canine femoral stems can be implanted using either a cemented or cementless procedures. Cementless stems have a porous coating of sintered beads on the tapered proximal section providing interference with reamed femoral canal causing friction and initial stability. The distal end of the stem has a tapered fit and contacts the lower region of the reamed femoral bone canal due to curvature of the stem providing distal stability. The porous coating encourages bone ingrowth in the cementless system or cement penetration resulting in long term stability. The cementless system uses either cast cobalt chromium stems with 250±50 μm beads of cobalt chromium or Ti-6Al-4V stem with 250±50 μm beads of chemically pure titanium.

A prosthetic hip-joint includes: a. a prosthetic acetabulum cup for implantation into a pelvis; b. a prosthetic femoral assembly which includes: i. a ball-shaped femoral head that during implantation becomes located within the cup; and ii. a femoral stem that is fixed at a first end to the head, and that has a second end distal from the first end which is adapted for implant into a medullary canal of a femur, and c. a liner assembly adapted to he secured to the cup and is also adapted to receive and to constrain the head against dislocation. In one aspect the hip-joint permits the head to rotate through an angle which exceeds at least 153 degrees while concurrently constraining the head against dislocation. In another aspect the hip joint constrains the head a dislocation by a preestablished amount of force which is adjustable during implantation thereof.

A surgical procedure for replacing a destructed hip joint with an artificial joint is disclosed. The present invention provides a two-incision minimally invasive surgery for total hip arthroplasty. This method comprises positioning of the patient on a lateral decubitus position and a series of surgical techniques including a first skin incision over the anterior side of the trochanteric area of the femur (ranging from 3 cm to 10 cm), intermuscular dissection between the Gluteus muscle (Gluteus minimus and medius) and Tensor fascia lata muscle, incision of the anterior joint capsule, osteotomy of the femoral neck, removal of the femoral head and neck, acetabular reaming and socket insertion, secondary skin incision over the Gluteus maximus muscle (ranging from 1 cm to 6 cm), dissection through the muscle fiber of the Gluteus maximus, intermuscular dissection between the Gluteus medius and Piriformis, partial incision of the joint capsule, femoral reaming, femoral stem insertion, femoral head insertion, joint capsule closure and skin closure.

A reamer system is provided which includes a cannulated reamer handle, and a corresponding cannulated reamer, which, when assembled and operated over a drill pin secured in a manner axially aligned with the stem of the femoral joint, enables the accurate and controlled reshaping of the femoral joint. The reamer is made up of a cutting form and a central guide, in which the guide is supported at the center of the cutting form by a bar structure. The bar structure includes portions which connect to and extend radially between the central guide and a peripheral edge of the cutting form. Optionally, the central guide includes a surface offset from a plane of the bar structure to a degree which enables that surface to contact an associated surface referenced to the bone, in order to prevent the cutting form from plunging so far over the bone as to potentially damage the femoral stem. This offset surface is preferably polished to reduce friction during relative rotational movement between this surface and the surface referenced to the bone. The offset surface is an axially perpendicular surface of a boss through which the drill pin is guided.

A surgical procedure for replacing a destructed hip joint with an artificial joint is disclosed. The present invention provides a two-incision minimally invasive surgery for total hip arthroplasty. This method comprises positioning of the patient on a lateral decubitus position and a series of surgical techniques including a first skin incision over the anterior side of the trochanteric area of the femur (ranging from 3 cm to 10 cm), intermuscular dissection between the Gluteus muscle (Gluteus minimus and medius) and Tensor fascia lata muscle, incision of the anterior joint capsule, osteotomy of the femoral neck, removal of the femoral head and neck, acetabular reaming and socket insertion, secondary skin incision over the Gluteus maximus muscle (ranging from 1 cm to 6 cm), dissection through the muscle fiber of the Gluteus maximus, intermuscular dissection between the Gluteus medius and Piriformis, partial incision of the joint capsule, femoral reaming, femoral stem insertion, femoral head insertion, joint capsule closure and skin closure.

A femoral head offset and neck length required in a femoral component to be engaged with an acetabular component are determined for establishing appropriate hip mechanics in a prosthetic hip joint. Alternate selected sleeves of different lengths are interposed between a trial femoral head component and a trial femoral stem component movable relative to one another to admit each selected sleeve, interoperatively, for serial trialing to determine an appropriate trial distance, the appropriate trial distance corresponding to the required femoral head offset and neck length in the prosthetic hip joint.

A method for placing a pelvic implant including a cup and a femoral stem includes planning at least one of a location of the cup within a pelvis and a location of the stem within a femur such that a combined anteversion between a predetermined cup component and a predetermined femoral stem component satisfies a predetermined combined anteversion.

Disclosed therein is a big femoral head and femoral head surface replacement, which are used for hip osteoarthritis and vascular necrosis of femoral head. As a person get older and aged, the weight bearing hip joint is indispensably changed to osteoarthritis and sometimes showed avascular necrosis of the femoral head with unknown etiology. The deformed femoral head and hip joint should be replaced with the THA. Till now, the total hip replacement is performed in such a way that the necrosed femoral head and a healthy femoral neck are all removed and a femoral stem is inserted into the marrow cavity, and in this case, a small femoral head causes a reduction of a range of motion and dislocation of the hip joint occasionally, and osteolysis due to abrasion of plastic acetabular liner. In case of a conventional femoral head surface replacement (hereinafter, called “conventional FHSR”), a complication of femoral neck fracture and could not combined use with conventional THA. Recently, hard bearing system such as metal on metal THA or ceramic on ceramic THA without using plastic has been introduced to solve the problem of osteolysis due to abraded plastic particles generated when the THA is worn out as time goes. But there also have many problems as a limited range of motion, resected normal femoral neck and difficulties of rereplacement of the femoral stem. Because of the big femoral head or the FHSR can increase the range of motion and lower dislocation rate these devices are gradually widespread in young active person and Asian peoples. This invented design of the modularity gives the convenience to the surgeon and economically lower burden to patients to use of the FHSR and big femoral head system. The related accessory showed initial stability of the FHSR during operation and prevent from femoral neck fracture in follow-up periods.

An apparatus for orienting a prosthetic femoral head relative to an acetabulum comprises a femoral stem and a femoral head member. The femoral stem is configured to be received within the intramedullary canal of a femur. The femoral head member is configured to couple to the femoral stem and further configured to be received in the acetabulum. The femoral head member further comprises an indicia configured to orient a relative position of the prosthetic femoral head to the acetabulum such that the indicia signifies proper relative position of the prosthetic femoral head in the acetabulum.

The femoral hip implant is defined by a femoral ball and a femoral stem. The femoral stem has a proximal end, a distal end and a length. The femoral stem extends from the femoral ball and terminates at the distal end. The femoral stem is arranged and configured to be received by a femur bone. A method of use is also provided.

A femoral stem 2 for artificial hip joint is provided that is capable of tightly fixing a greater trochanter and is suitable for treatment of transcervical fracture where it is necessary to fix the greater trochanter. The femoral stem 2 comprising: a stem member 20 including a distal part 21 of the stem member which is inserted in a medullary cavity of a femur and fixed therein and a proximal part 22 of the stem member which has a neck 26 for fixing an artificial head and is positioned at a proximal end of the distal part, the distal part and the proximal part being integrated or separable; a plate fixing portion 36 which is detachably attached at a top of the proximal part; and a greater trochanter plate 3 for depressing the greater trochanter 71, the greater trochanter being fixed to the plate fixing portion 36 at a certain angle or fixed to the plate fixing portion so as to adjust an angle. Since the greater trochanter plate 3 is fixed onto the femoral stem 2 of the present invention, the greater trochanter is tightly fixing and thus the fixation can be stabilized. Furthermore, since the greater trochanter plate 3 is fixed at the top of the proximal part 22, the greater trochanter plate 3 covers the top of the greater trochanter 71 when the greater trochanter 71 is fixed. Therefore upward displacement of the greater trochanter by a gluteus medius musculus can be effectively suppressed.

Bipolar prostheses which include various structures and other techniques for optimizing material wear and mechanical strength properties. Such prostheses feature, for example, improved resistance to polyethylene wear while also reducing potential for dislocation of the femoral stem from the prosthesis. Such techniques and structures include varying wear resistance and mechanical strength treatment in various components of the prostheses or portions of those components as desired to improve, accentuate or optimize wear performance and dislocation reduction, locking ring structural features, structures for retaining locking rings in the bipolar prosthesis shell, and structures for limiting or reducing movement or rotation of locking rings and liners in bipolar prosthesis shells.

A total hip femoral prosthesis provides high lateral offset with a construct including a conventional length neck. The neck is shifted medially to position the head center in a high offset location. The proximal medial portion of the stem is augmented to provide adequate support to the medialized neck. Modular components are disclosed. Methods of using the prosthesis in total hip arthroplasty are described.