Smith & Nephew Richards Inc.

Smith + Nephew

Other

Mayo Foundation for Medical Education and Research

Jennifer J Lackey

Gregory C Marik

Leonard J Tokish, Jr

Scott Elliott

Jeffrey G Roberts

M Scott Elliott

Brian Schumacher

James A Rand

Robert Cofield

Thomas Andrew Carls

Chris E Johnson

Abraham Biglari Salehi

Ramon B Gustilo

Raymond H Roberson, Jr

Thomas B Buford, Iii

Steven J Imbimbo

Steve M Tammi

A posterior stabilized/constrained reamer guide is provided that enables a surgeon to prepare a patient s distal femur to receive either a posterior stabilized or a constrained type femoral component. The instrument guide has an opening the largest anterior to posterior housing size. For example, a constrained housing has a longer anterior to posterior dimension than a posterior stabilized housing. The apparatus of the present invention provides an improved reamer guide that addresses differences in housing sizes and necessary bone removal. The apparatus provides a housing guide that accepts either a posterior stabilized collet or a constrained collet. Each of the collets accepts a rotary reamer or a box chisel. During surgery, the reamer is first used to form a cylindrically-shaped or oval shaped cut. The box chisel then removes additional bone to create a rectangular or squared opening. This insures that only the necessary bone is removed for each housing depending upon the one selected by the surgeon.

Posterior stabilized/constrained reamer guide

A distal femoral sizing instrument includes an intramedullary rod for referencing the patient's intramedullary canal. A valgus module mounts to the intramedullary rod at a bore of the valgus. The bore of the module has a slant with respect to the flat reference surface of a valgus block. The module slidably connects to the block. The valgus block, referencing guide and a stylus (for connecting the valgus block and cutting together) are removed as a unit before shaping of the distal femur. An indexing system includes a gauge having a series of openings corresponding to 'anterior' referencing and to 'posterior' referencing. During anterior referencing, the gauge allows the surgeon to select the next smaller size prosthesis if the size falls in between available sizes. In posterior referencing, the gauge allows the surgeon to select the next larger size prosthesis if the gauge measures a size that falls in between available sizes.

Distal femoral cutting guide apparatus with anterior or posterior

A modular tibial trial prosthesis for attachment to a patient's surgically cut proximal tibia includes a tibial tray having proximal and distal surfaces, the distal surface to be fitted against the patient's surgically prepared proximal tibia during knee joint replacement surgery. The proximal surface of the tray accepts any one of a plurality of plastic liner inserts that fits the tray at the proximal tray surface with an interlocking connection. The liner inserts each have a distal surface for attachment to the tray and a proximal articulating surface that is receptive of a distal femoral articulating surface. The proximal articulating surface has concavely-shaped portions. The concavely-shaped portions of the liner inserts provide different articular geometries for selection by the user. A plurality of spacers of different thicknesses can be positioned in between a selected one of the plastic liner inserts and the tibial tray. Each spacer has proximal and distal surfaces. The spacers have connecting portions on each of said proximal and distal surfaces for forming respective connections with a tibial tray and a selected plastic liner insert. The liner inserts each have connecting portion on the distal surface thereof for connecting to the proximal surface of the spacer and to the proximal surface of the tray. The liner inserts and spacers each have a periphery in the form of a sidewall that extends generally perpendicular to the proximal surface of the patient's transversely cut proximal tibia. The periphery of the insert and spacers are of corresponding shape.

Modular trial tibial insert

A knee cutting instrument apparatus includes an elongated alignment rod that can enable a surgeon to define alignment with a patient's long bone. An instrument block body can slide upon the alignment rod between its end portions. A locking member forms a connection with the rod at a selected position along the rod. The locking member includes a cam locking arrangement that rotates about a pivot on the instrument body. The cam has a handle portion or arm that enables a user to rotate the cam and its locking tab about its pivot. Part of the locking cam includes a locking tab having a slot that extends circumferentially about ninety degrees (90.degree.) around the pivot of the cam. The slot is positioned radially in between the pivot and the periphery of the locking member at a locking member bearing surface. The slot provides a closed end portion and an open end portion that communicates with the locking member periphery at a positioned spaced away from the bearing surface. The slot is preferably sufficient long enough that it extends circumferentially the full length of the bearing surface.

Orthopaedic cutting instrumentation with cam locking arrangement

A distal femoral cutting instrument includes an intramedullary rod for referencing the patient's intramedullary canal. A valgus block with a flat reference surface mounts to the intramedullary rod at a bore of the valgus block. The bore of the block has a slant with respect to the flat reference surface on the valgus block. The reference surface defines a line that is normal to the mechanical axis of the patient while the bore of the valgus block tracks the patient's biomechanical axis. A distal femoral cutting block removably attaches to the valgus block and provides a flat cutting guide surface for shaping the patient's distal femur. The valgus block, intramedullary rod, and a stylus (for connecting the valgus block and cutting together) are removed as a unit before shaping of the distal femur. An indexing system includes a gauge having a series of openings corresponding to 'anterior' referencing and to 'posterior' referencing. During anterior referencing, the gauge allows the surgeon to select the next smaller size prosthesis if the size falls in between available sizes. In posterior referencing, the gauge allows the surgeon to select the next larger size prosthesis if the gauge measures a size that falls in between available sizes.

A method and apparatus for installing a knee prosthetic component on a patient's tibia includes the selection by a surgeon of one of a plurality of reamers, each of the reamers having a different cutting size diameter such as for example between ten and twenty-two millimeters of cutting diameter. The reamer is initially selected as a very small reamer and the surgeon places progressively larger cutting diameter reamers in the patient's intermedullary canal until resistance or until the reamer becomes stuck. When the surgeon finds a reamer that is sized so that it will ream and cut cortical bone preferably a full three hundred and sixty degrees (360.degree.), the patient's intramedullary canal is cut and reamed into a depth which corresponds to the length of the stem portion of the femoral prosthetic component. Instrumentation is installed on the upper generally cylindrically shaped portion of the reamer as soon as cutting and reaming is completed and without removal of the reamer from the intermedullary canal. This insures that cutting instrumentation will be properly oriented with regard to the hole that is cut and reamed to prepare the intermedullary canal.

Instrumentation for long stem surgery

A modular humeral prosthesis that can be custom fitted to a particular patient by interchanging sizes of the various components by a surgeon interoperatively. The prosthesis features a humeral head having a hemispherically shaped outer surface for placement within the glenoid cavity of a human scapula, the head including on its undersurface a recessed center portion having a first cooperating connecting means. The body has a proximal end and a distal end, with the proximal end including an angled platform having a second cooperating connecting means for engagement with said first connecting means, and the distal end having a third cooperating connecting means. The body also includes a plurality of fins. A cylindrical primary stem has a proximal end and a distal end, the proximal end having a forth cooperating connecting means for engagement with said third connecting means, and the distal end having a fifth cooperating connecting means. A cylindrical secondary stem has a proximal end and a distal end, the proximal end having a sixth cooperating connecting means for engagement with said fifth connecting means, and the distal end having a tip for insertion within the medullary canal of a resected human humerus.

Modular humeral component system

An apparatus for guiding the resection of the head of a humerus is provided. The apparatus includes an intramedullary alignment member having a longitudinal axis and structured for substantial axial alignment with the intramedullary canal of the bone, one point of reference for the resection. The apparatus also includes an extramedullary alignment member and a collar rotatably mounted on the intramedullary member for rotating the extramedullary alignment member about the longitudinal axis of the intramedullary alignment member to a desired degree of retrotorsion. A cutting block and a first shaft and a second shaft in a perpendicular orientation relative to the first shaft for positioning the cutting block in a desired orientation relative to the head of the bone are also provided.

Intramedullary referenced humeral head resection guide

Improved femoral instrumentation for long stem surgery provides a femoral drill guide with interchangeable femoral collets, a femoral reamer, and a femoral anterior/posterior cutting block with an adaptable anterior femoral ledge. This instrumentation allows all cuts to be made relative to the long stem component of a femoral prosthesis which will fit in the hole formed by the reamer with the collet and cutting block both oriented on the reamer, and all cuts made by the surgeon will be oriented relative to the long stem or spike component of the femoral prosthesis.

Femoral instrumentation for long stem surgery

A plurality of various shaped wedges, each wedge having an upper and lower face, each face including a plurality of spaced aligned protrusions adapted to engage a plurality of channels formed in the under surface of the tibial base, the protrusions registering with the channels to allow positioning of the wedge relative to the shape of the tibial component in various positions along the edge of the component, so that the plurality of wedges may be positioned to align themselves with the edge of the tibial component, and therefore in addition to providing a spacer between the bone and the undersurface of the component, to be secured within the same confined area as the component.

System of inserts for the tibial component of a knee prosthesis

A femoral component base having a pair of laterally spaced apart condylar portions, each of which has an external surface that is smoothly convexly curved anterior-posteriorly to match generally the distal profile of the anatomical femoral condyle and smoothly convexly curved laterally throughout its antero-posterior extent. The external convexly curved surfaces engage the tibial component having a platform portion laterally with spaced apart concavities, each of which would receive one of the condylar portions of the femoral component to allow antero-posterior rotation between the components during use of the joint. The femoral component includes a modular member having adjustable plates for adjusting the position of the femoral component in response to the bone condition discovered during surgery. The tibial, femoral and modular components further include a triangular, ramp post and corresponding confined recess to limit flexion and undesirable lateral movement.

Growing community of inventors

Memphis, TN, United States of America

Jennifer J Lackey