# US 10,245,149 B2 · Reverse total hip replacement > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,245,149 B2 - Document ID: US10245149B2 - Status: Granted - Kind: B2 - Application number: 15/225,873 - Filed: 2016-08-02 - Published: 2017-02-09 - Granted: 2019-04-02 - Earliest claimed: 2015-08-03 - Applicants: Nicholas John Loffredo - Inventors: Nicholas John Loffredo - Web page: https://patentgrep.com/patent/US10245149B2 ## CPC - A61F 2/34: Acetabular cups - A61B 17/1666: {for the acetabulum} - A61B 17/1746: {for the acetabulum} - A61F 2/3603: {implanted without ablation of the whole natural femoral head (endoprosthetic cartilage A61F2/30756)} - A61F 2/3609: {Femoral heads or necks; Connections of endoprosthetic heads or necks to endoprosthetic femoral shafts (A61F2/3601 takes precedence)} - A61F 2/4609: {of acetabular cups} - A61B 17/86: Pins or screws {or threaded wires; nuts therefor (A61B17/72 take precedence)} - A61F 2002/30332: {Conically- or frustoconically-shaped protrusion and recess} - A61F 2002/305: {Snap connection} - A61F 2002/30878: {with non-sharp protrusions, for instance contacting the bone for anchoring, e.g. keels, pegs, pins, posts, shanks, stems, struts} - A61F 2002/3483: {having a convex shape, e.g. hemispherical heads} - A61F 2002/3615: {having a concave shape, e.g. hemispherical cups} - A61F 2002/4629: {connected to the endoprosthesis or implant via a threaded connection} - A61F 2002/4687: {Mechanical guides for implantation instruments} - A61F: FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS (dental prosthetics A61C) - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) ## Abstract A reverse total hip prosthesis is characterized by a femoral cup component and an acetabular ball component and is used for reconstruction of a hip joint. The prosthesis reverses the mechanics across the joint medializing the center of rotation, preventing dislocation in a posterior direction. Both ball and socket portions of the components lie outside of bone enabling larger sizing of the femoral and acetabular components improving stability, regardless of the size of the patient's anatomy. A method for reverse hip prosthesis implantation eliminates reaming through the base of the acetabulum preserving acetabular bone stock. ## Claims ### Claim 1 A reverse hip replacement prosthesis device comprising: a femoral component having a femoral stem portion that is configured for fitting into a human femur and supports a femoral cup portion attached to a saucer-shaped spacer; and an acetabular component having: (i) an acetabular base formed as a spherical segment having a spherical interface surface that extends between a first flat surface and a second flat surface parallel to the first flat surface, wherein a central barrel having a keyed depression extends from the second flat surface, and wherein the acetabular base includes one or more tunnels formed through the spherical interface surface that define an anterior-to-posterior orientation for fastening the acetabular base to a patient's acetabulum; (ii) a hemispheric acetabular ball that is sized for articulating contact with the saucer-shaped spacer and featured for engagement with the central barrel. ### Claim 2 (depends on 1) The device of claim 1 wherein the keyed depression further has a screw threading to allow attachment of a guide for fastener placement. ### Claim 3 (depends on 1) The device of claim 1 wherein the stem portion is configured for fitting into a femoral neck. ### Claim 4 (depends on 1) The device of claim 1 wherein the stem portion is configured for fitting into an intramedullary canal of a proximal femur. ### Claim 5 (depends on 1) The device of claim 1 wherein the femoral cup and stem portions are formed of the same material. ### Claim 6 (depends on 1) The device of claim 1 wherein the acetabular ball has a central cavity for engagement with the central barrel of the acetabular base. ### Claim 7 (depends on 6) The device of claim 6 wherein the cavity of the acetabular ball and the central barrel of the acetabular base are featured for a tapered fitting. ### Claim 8 (depends on 1) The device of claim 1 wherein the saucer-shaped spacer is attached using a snap ring and groove. ### Claim 9 (depends on 1) The device of claim 1 wherein the saucer-shaped spacer is formed of a biocompatible material taken from the group consisting of a cobalt-chromium alloy, an alumina-alumina alloy, a zirconium alloy, an oxinium alloy, a ceramic, and a titanium alloy. ### Claim 10 (depends on 9) The device of claim 9 wherein the saucer-shaped spacer further has a hydroxyapatite coating. ### Claim 11 (depends on 1) The device of claim 1 wherein the saucer-shaped spacer is formed of a biocompatible material taken from the group consisting of polyethylene, ultra-high molecular weight polyethylene (UHMWPE), and cross linked UHMWPE. ### Claim 12 A reverse hip replacement prosthesis device comprising: a femoral component having a femoral stem portion that is configured for fitting into a femoral neck and supports a femoral cup portion attached to a saucer-shaped spacer; and an acetabular component having: (i) an acetabular base formed as a spherical segment having a spherical interface surface that extends between a first flat surface and a second flat surface parallel to the first flat surface, wherein a central barrel having a keyed depression extends from the second flat surface, and wherein the acetabular base includes one or more tunnels that extend through the spherical interface surface and that define an anterior-to-posterior orientation for fastening the acetabular base to a patient's acetabulum; (ii) a hemispheric acetabular ball that is sized for articulating contact with the spacer and featured for engagement with the central barrel by a tapered fitting.