# US 11,298,231 B2 · Percutaneous osseointegrated implant assembly for use in supporting an exo-prosthesis > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,298,231 B2 - Document ID: US11298231B2 - Status: Granted - Kind: B2 - Application number: 16/383,363 - Filed: 2019-04-12 - Published: 2019-08-08 - Granted: 2022-04-12 - Earliest claimed: 2011-06-06 - Assignees: Joseph A. Longo; University of Utah Research Foundation - Applicants: University of Utah Research Foundation; Joseph A. Longo - Inventors: Kent N. Bachus; Sujee Jeyapalina; James Peter Beck; Roy Bloebaum; Jayant P. Agarwal; Joseph A. Longo; Erik Kubiak; Brian Mueller Holt - Web page: https://patentgrep.com/patent/US11298231B2 ## CPC - A61F 2/2814: {Bone stump caps} - A61F 2/78: Means for protecting prostheses or for attaching them to the body, e.g. bandages, harnesses, straps or stockings for the limb stump - A61F 2002/0091: {Having cellular growth inhibitors} - A61F 2002/30028: {differing in tissue ingrowth capacity, e.g. made from both ingrowth-promoting and ingrowth-preventing parts} - A61F 2002/30299: {umbrella-shaped or mushroom-shaped} - A61F 2002/30576: {with extending fixation tabs} - A61F 2002/30589: {Sealing means} - A61F 2002/30594: {slotted, e.g. radial or meridian slot ending in a polar aperture, non-polar slots, horizontal or arcuate slots} - A61F 2002/30604: {modular} - A61F 2002/30729: {Separate collars} - A61F 2002/30784: {Plurality of holes} - A61F 2002/30879: {Ribs} - A61F 2002/30932: {for retarding or preventing ingrowth of bone tissue} - A61F 2002/7887: {for connecting limb exoprostheses to the stump bone} - 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) ## Abstract An implant assembly for a long bone is adapted to support an exo-prosthesis. The assembly includes a stem, a subdermal component and a percutaneous post. The stem has a proximal end that is adapted to be received in a surgically prepared medullary canal of the long bone, and a distal end having a surface that is adapted to promote bone ingrowth. The subdermal component includes a proximal portion that is adapted for attachment to the distal end of the stem, and a fixation surface that is adapted to promote soft tissue fixation. The percutaneous post has a proximal end that is adapted to be attached to the subdermal component. ## Claims ### Claim 1 A method of securing an exo-prosthesis to a selected bone of a limb of an individual in need thereof, comprising: preparing a medullary cavity of a selected long bone for receipt of at least a portion of an implant assembly, the preparing including performing an osteotomy by creating a cut through the selected long bone that is generally perpendicular to the longitudinal axis of the selected long bone; inserting at least a proximal end of a stem of the implant assembly within the prepared medullary cavity of the selected bone, wherein a distal end of the stem comprises a substantially flat collar having a substantially flat surface that extends perpendicular to the longitudinal axis of the selected long bone and that engages the selected long bone perpendicular to the longitudinal axis of the selected long bone, thereby forming a direct seal with the selected long bone; attaching a proximal portion of a subdermal component to the distal end of the stem; wherein the subdermal component comprises: a low energy surface configured to inhibit bio-adhesion disposed on the proximal portion of the subdermal component; a distal portion comprising a fixation surface having a porous structure configured to promote soft tissue fixation; and an intermediate portion disposed between the distal portion and the proximal portion and comprising a transition surface having a variable porosity configured to increasingly promote bio-adhesion and/or soft tissue fixation along a length of extension from the low energy surface to the fixation surface; and attaching a proximal end of a percutaneous post to the subdermal component. ### Claim 2 (depends on 1) The method of claim 1, further comprising: attaching a flexible elastomeric stoma shield comprising a plurality of ventilation holes to the percutaneous post of the implant assembly such that the stoma shield is disposed over an amputation stump of the limb of the individual. ### Claim 3 (depends on 1) The method of claim 1, wherein the distal end of the stem comprises a circumferential porous titanium coating. ### Claim 4 (depends on 1) The method of claim 1, wherein the stem of the implant assembly further comprises a plurality of splines, each extending substantially parallel to a longitudinal axis of the stem. ### Claim 5 (depends on 1) The method of claim 1, wherein the stem of the implant assembly further comprises a central slot that substantially bisects the proximal end of the stem of the implant assembly and thereby promotes fixation within the selected long bone. ### Claim 6 (depends on 3) The method of claim 3, wherein the continuous circumferential porous titanium coating is recessed relative to outer surfaces of adjoining portions of the stem. ### Claim 7 (depends on 1) The method of claim 1, further comprising: attaching a proximal end of an adapter to a distal end of the percutaneous post; and attaching a distal end of the adapter to the exo-prosthesis. ### Claim 8 (depends on 1) The method of claim 1, wherein the proximal portion of the subdermal component comprises a radial dimension that is greater than a radial dimension of the distal end of the stem. ### Claim 9 (depends on 1) The method of claim 1, wherein the distal portion of the subdermal component has a radial dimension that is greater than a radial dimension of the proximal portion of the subdermal component. ### Claim 10 (depends on 1) The method of claim 1, wherein at least a portion of the subdermal component has a concave profile. ### Claim 11 (depends on 1) The method of claim 1, wherein at least a portion of the subdermal component has a convex profile. ### Claim 12 (depends on 1) The method of claim 1, wherein the subdermal component is substantially cylindrical. ### Claim 13 (depends on 1) The method of claim 1, wherein a surface of the distal end of the stem comprises a porous structure configured to support osseointegration. ### Claim 14 (depends on 1) The method of claim 1, wherein the low energy surface of the proximal portion of the subdermal component has been treated to increase its hydrophobic characteristics. ### Claim 15 (depends on 1) The method of claim 1, wherein the low energy surface of the proximal portion of the subdermal component is formed utilizing a process selected from the group consisting of abrasive blasting, burnishing, grinding, buffing, chemical vapor deposition and combinations of such processes. ### Claim 16 (depends on 1) The method of claim 1, wherein the porous structure of the fixation surface is further configured to support osseointegration. ### Claim 17 (depends on 1) The method of claim 1, wherein the transition surface of the intermediate portion of the subdermal component has been treated to increase its hydrophobic characteristics relative to the fixation surface. ### Claim 18 (depends on 1) The method of claim 1, wherein the transition surface of the intermediate portion of the subdermal component is formed utilizing a process selected from the group consisting of abrasive blasting, burnishing, grinding, buffing, chemical vapor deposition and combinations of such processes. ### Claim 19 (depends on 1) The method of claim 1, wherein: the proximal end of the percutaneous post comprises at least one anti-rotation tab extending proximally away from the proximal end, and the attaching the proximal end of the percutaneous post to the subdermal component comprises coupling the at least one anti-rotation tab to the subdermal component.