99 results about "Hip arthroplasty" patented technology

One or more rigid components associated with an articulating bone are used to encase, encapsulate, contain, or otherwise protect a compressible/resilient member. The embodiments are applicable not only to artificial disc replacement (ADR) devices, but also to joint situations including total knee and hip arthroplasty. The cushion elements in the preferred embodiments include synthetic rubbers, hydrogels, elastomers, and other polymeric materials such as viscoelastic polymers and foam polyurethanes. The invention effectively combines the advantages of such materials (cushioning, shape memory, and expansion after insertion in the case of hydrogels), while providing increased protection, particularly the elimination of shear stresses. When applied to an ADR, the invention also minimizes the risk of extrusion.

A system for calculating a position and orientation of an acetabular cup in computer-assisted surgery comprises a first trackable reference secured to a pelvis, with a frame of reference being associated with the first trackable reference. A device is positionable between a femoral neck and the acetabulum of the pelvis in a known relation, the device having a second trackable reference. Sensors track the trackable references for position and orientation. A position/orientation calculator calculates a position and orientation of the frame of reference and of the device and for determining an orientation of the neck axis with respect to the frame of reference from the known relation at a desired position of the femur. An implant position/orientation calculator provides cup implanting information with respect to the orientation of said neck axis as a function of the tracking for position and orientation of at least the first trackable reference.

A broaching instrument and method using a segmented broach head. First and second broach segments are laterally engageable with each other in vivo, and are aligned with each other on a common longitudinal axis when so engaged. The method involves making a small anterior incision adjacent a patient's femur, inserting the broach segments sequentially through the anterior incision, interconnecting the plurality of broach segments in vivo, connecting the broach handle to the broach segments, and broaching the proximal medullary canal with the assembled multi-part broach instrument.

One or more rigid components associated with an articulating bone are used to encase, encapsulate, contain, or otherwise protect a compressible/resilient member. The embodiments are applicable not only to artificial disc replacement (ADR) devices, but also to joint situations including total knee and hip arthroplasty. The cushion elements in the preferred embodiments include synthetic rubbers, hydrogels, elastomers, and other polymeric materials such as viscoelastic polymers and foam polyurethanes. The invention effectively combines the advantages of such materials (cushioning, shape memory, and expansion after insertion in the case of hydrogels), while providing increased protection, particularly the elimination of shear stresses. When applied to an ADR, the invention also minimizes the risk of extrusion.

Broaching instruments divided into multiple parts to reduce the size of incisions necessary to perform a total hip arhroplasty, minimizing trauma to tissue surrounding the hip joint. One approach is to divide the broach head into first and second segments for insertion through posterior and anterior incisions, respectively, and interconnection within the patient. Methods of preparing the proximal medullary canal of a femur for receiving a hip stem implant utilize the multi-part broaching instruments and two-incision techniques to introduce the broaching instruments into the patient for broaching the canal in preparation for receiving the implant.

An expanding reamer for reaming or cutting a concave surface, for example, for reaming an acetabulum in preparation for implanting a prosthetic component during a hip arthroplasty. A rotating shaft cooperates with a surgical drill or other power source at one end and rotates a reamer head at the other end, and an actuation system expands one or more blades on the reamer head. The reamer head comprises one or more cutting blades, which act as segments of a cutting sphere, wherein the blades are expandable in directions non-parallel to the plane of the respective blades in order to enlarge the cutting sphere. Upon rotation of the reamer head, the blade(s) form a portion of an effective cutting sphere that is preferably greater-than-180-degrees; this allows greater flexibility in placement of the shaft of the reamer relative to the surface being reamed, for example, relative to the center of axis of the acetabulum. In one embodiment, two parallel blades move out away from each other and away from the rotational axis of the device, staying parallel to each other to become, in effect, more distanced, but still parallel, segments of a larger cutting sphere. In another embodiment, two blades start generally parallel to each other and to the rotational axis of the device, but pivot out from each other in directions generally perpendicular to their respective blade planes, again becoming more distanced, but not parallel, segments of a larger cutting sphere.

The invention relates to apparatus and methods for facilitating total hip arthroplasty.

A hip prosthesis (20) having a shell (22), liner (24), and retainer ring (26) is utilized for hip arthroplasty. The liner (24) fits inside the shell (22), which is attached to a patient's pelvis, and the retainer ring (26) engages a terminal liner margin (54) to inhibit expansion of and decrease the size of a restricted liner opening (72) defined by the liner margin (54). By inhibiting expansion of the liner opening (72), the ball (92) of a patient's femur (90) is securely held in the liner (24). In one embodiment, the liner (98) is inhibited from rotation relative to the shell (96) by a plurality of protrusions (106) which mate with recesses (102) in the shell (96). In that embodiment, the liner (98) is provided with catch lips (108) to hold the liner (98) in the shell (96) and a positioning flange (110) which operates to form a relief gap (120) between the shell (96) and the liner (98). In another embodiment, the retainer ring comprises an attachment portion (128) and a retainer portion (130) with a threaded connection (132) between the attachment portion (128) and the retainer portion (130).

a minimal invasive hip arthroplasty device is provided. The system comprises a long nail portion, a lag screw portion, distal locking screws, and a resurfacing head. The long nail portion is inserted into a shaft body of a femur from a top portion of the femur and disposed in the femur. The lag screw portion engages and anchors at the long nail portion through a lag screw hole, and the lag screw portion is inserted into a neck of the femur. The distal locking screws queue through the shaft body of the femur perpendicularly and fix the long nail portion to the femur further. The resurfacing head comprises a cup portion configured to cover a head of the femur and a fixing pin portion configured to be inserted into the head and the neck of the femur and engaging the lag screw portion through a resurfacing head hole.

This disclosure is directed to a resilient interpositional arthroplasty implant for application into joints to pad cartilage defects, cushion joints, and replace or restore the articular surface, which may preserve joint integrity, reduce pain and improve function. The implant may endure variable joint compressive and shear forces and cyclic loads. The implant may repair, reconstruct, and regenerate joint anatomy, and thereby improve upon joint replacement alternatives. Rather than using periosteal harvesting for cell containment in joint resurfacing, the walls of this invention may capture, distribute and hold living cells until aggregation and hyaline cartilage regrowth occurs. The implant may be deployed into debrided joint spaces, molding and conforming to surrounding structures with sufficient stability to avoid extrusion or dislocation. Appendages of the implant may repair or reconstruct tendons or ligaments, and an interior of the implant that is inflatable may accommodate motions which mimic or approximate normal joint motion.

An impactor for positioning and inserting an acetabular cup into an acetabulum of a pelvis during hip arthroplasty is described. The impactor includes a guide element mounted to an elongated body and including first and second openings aligned with each other to define an axial passage. The first and second openings and the axial passage receive a guide pin therethrough that is pinned in a fixed position to the pelvis. The guide element provides a mechanical orientation guide which restricts an angular orientation of the impactor relative to the guide pin when the guide pin is pinned in the fixed position relative to the pelvis and received through the first and second openings of the guide element. Centering the openings of the guide element relative to the guide pin in the fixed position accordingly achieves a desired orientation of the impactor within a predetermined angular tolerance.

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.

An external proximal femoral prosthesis for total hip arthroplasty (THA) is described, which fundamentally comprises a shell configured a hollow, thin-wall, asymmetric bell shape and a plurality of tension anchor means. An inner transverse cross contour of the shell forms a cavity, which could be affixable to a profile of outer surface of the area of neck, trochantic bed and calcar of the proximal femur. A neck portion of the shell is compatible with acetabular components (ball and cup). The prosthesis is mechanically fastened by tension anchor means during the operation and further biologically secured by in-growing bone through the side holes on the shell wall and into its interior coating surface of implant wall thereafter. The loading force on the femoral head would be well transferred and distributed on the shell and then directly conducted into the cortical bone of the femoral shaft therearound.

Femoral head modular resurfacing systems are described. The systems primarily include a head component and a stem component. The configuration of the head component and stem components allow for minimum invasiveness into the femur head region, thus conserving greater amounts of bone tissue than would be possible with conventional hip replacement systems. The systems also provide for various angles and offsets to be achieved between the systems and the femur head. The systems are useful in partial hip replacement procedures, as well as total hip replacement procedures, in which case an optional acetabular component would also be employed.

The instant invention is a novel method and apparatus for minimally invasive treatment of unstable pelvic ring injuries combined with fixation of acetabular cup assemblies for total hip arthroplasty. Fixation means and acetabular cup assemblies are affixed to the ilia and subcutaneous anteriorly bowed elongated rods/plate including possibly a subcutaneous posterior plate are connected between the fixation means.

Novel femoral implants for use in hip arthroplasty are described and illustrated. The femoral implant comprise a stem and neck portion, with the neck portion having a novel configuration that provides for improved range in motion for the prosthesis without compromising strength of the implant.

The present invention includes a measurement/assessment technique based upon a collection of angular and distance measurements taken with respect to x-ray visible osteo-anatomical artifacts to arrive at accurate and easily reproducible component placement. In the context of hip arthroplasty surgery the method of the present invention involves determinations, from two different two-dimensional views, of the angles and distances from osteo-anatomical artifacts, to allow a surgeon to approach a hip resurfacing operation with the distance and angular measurements to be translated into actual markings and device settings to be able to accurately ream the femoral head structure, position and affix the femoral cap and acetabular cup components in accordance with the pre-determined distance and angular measurements.