# US 11,076,897 B2 · Orthopedic locking screw for an orthopedic fastening system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,076,897 B2 - Document ID: US11076897B2 - Status: Granted - Kind: B2 - Application number: 15/776,667 - Filed: 2015-11-18 - Published: 2018-12-27 - Granted: 2021-08-03 - Earliest claimed: 2015-11-18 - Assignees: Stryker European Holdings I, LLC - Applicants: Stryker European Holdings I, LLC - Inventors: Manfred Wieland; Nils Zander - Web page: https://patentgrep.com/patent/US11076897B2 ## CPC - A61B 17/725: {with locking pins or screws of special form} - A61B 17/8042: {the additional component being a cover over the screw head} - A61B 17/863: {with thread interrupted or changing its form along shank, other than constant taper} - A61B 17/8635: {Tips of screws} - A61B 17/866: {Material or manufacture} - A61B 17/8685: {comprising multiple separate parts} - A61B 17/686: {Plugs, i.e. elements forming interface between bone hole and implant or fastener, e.g. screw} - A61B 17/8057: {the interlocking form comprising a thread} - A61B 2017/8655: {with special features for locking in the bone} - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) ## Abstract An orthopedic locking screw is configured to be retained inside a bore of an orthopedic implant. The orthopedic locking screw includes a shaft extending axially, a casing secured around an outer surface of the shaft, a deformable thread disposed along an outer surface of the casing, and a forward external thread disposed on the shaft. The forward external thread has a pitch that is different from a pitch of the deformable thread of the casing. Further, an orthopedic locking screw is provided, wherein projections and the casing are alternately arranged on the outer surface of the shaft. ## Claims ### Claim 1 An orthopedic locking screw configured to be secured through a bore, provided with an engagement feature, of an orthopedic implant, the orthopedic locking screw comprising: a shaft extending along an axis between a first end and a second end; a casing having a first end proximate the first end of the shaft and a second end proximate the second end of the shaft, the casing secured to an outer surface of the shaft such that during securing of the orthopedic locking screw through the bore of the orthopedic implant the casing is rotationally and axially fixed around the outer surface of the shaft and prevented from slipping radially relative thereto; a deformable thread disposed along an outer surface of the casing configured to deform when the deformable thread engages the engagement feature as the orthopedic locking screw is secured through the bore of the orthopedic implant; and a forward external thread disposed on the shaft between the first end of the casing and the first end of the shaft, wherein the forward external thread has a pitch that is different from a pitch of the deformable thread of the casing. ### Claim 2 (depends on 1) The orthopedic locking screw of claim 1, wherein the forward external thread has a pitch that is larger than the pitch of the deformable thread of the casing. ### Claim 3 (depends on 1) The orthopedic locking screw of claim 1, wherein the deformable thread is an external thread and the engagement feature of the bore is an internal thread so as to retain the shaft in the bore. ### Claim 4 (depends on 1) The orthopedic locking screw of claim 1, wherein the deformable thread is a continuous thread extending from adjacent the first end of the casing to the second end of the casing. ### Claim 5 (depends on 1) The orthopedic locking screw of claim 1, wherein the deformable thread has a minor diameter and a major diameter, wherein at least one of the minor and major diameters is constant along the length of the deformable thread. ### Claim 6 (depends on 5) The orthopedic locking screw of claim 5, wherein the outer diameter of the deformable thread of the casing is larger than an outer diameter of the forward external thread. ### Claim 7 (depends on 1) The orthopedic locking screw of claim 1, wherein the casing is integrally formed with the deformable thread and wherein at least one of the casing and the deformable thread is formed of a plastically deformable material. ### Claim 8 (depends on 1) The orthopedic locking screw of claim 1, further comprising a rear external thread disposed on the shaft between the second end of the shaft and the second end of the casing. ### Claim 9 (depends on 8) The orthopedic locking screw of claim 8, wherein the rear external thread has a pitch that is equal to the pitch of the forward external thread. ### Claim 10 (depends on 8) The orthopedic locking screw of claim 8, wherein at least one of the forward external thread and the rear external thread is axially spaced apart from the casing. ### Claim 11 (depends on 8) The orthopedic locking screw of claim 8, wherein an outer diameter of the rear external thread is larger than the outer diameter of the deformable thread of the casing and wherein the outer diameter of the rear external thread is equal to or larger than the outer diameter of the forward external thread. ### Claim 12 (depends on 1) The orthopedic locking screw of claim 1, wherein the casing has an outer cross-sectional width that is larger than a cross-sectional width of the first end of the shaft adjacent the first end of the casing. ### Claim 13 (depends on 1) The orthopedic locking screw of claim 1, wherein the first end of the casing is tapered radially inwardly toward the outer surface of the shaft. ### Claim 14 (depends on 1) The orthopedic locking screw of claim 1, wherein the shaft comprises a polygonal or other non-circular profile that prevents the casing from rotationally slipping on the shaft. ### Claim 15 (depends on 1) The orthopedic locking screw of claim 1, further comprising a tip disposed at the first end of the shaft, wherein the tip comprises a self-tapping feature. ### Claim 16 (depends on 1) The orthopedic locking screw of claim 1, further comprising a drive member disposed at the second end of the shaft, the drive member comprising a head configured to engage with a rotational drive member, wherein the head forms a shoulder extending radially outwardly from an outer surface of the shaft to an outer surface of the head. ### Claim 17 (depends on 1) The orthopedic locking screw of claim 1, wherein a material of the casing is softer than a material of the shaft, the material of the casing preferably comprising at least one of a plastic and a metal, and the material of the shaft preferably comprising at least one of a plastic, a metal, and a ceramic. ### Claim 18 (depends on 1) The orthopedic locking screw of claim 1, wherein the orthopedic locking screw is configured to be secured through an orthopedic implant formed of a biocompatible material and comprising the bore. ### Claim 19 An orthopedic fastening system, comprising: an orthopedic implant comprising a threaded bore; and an orthopedic locking screw configured to be restrained inside the threaded bore, the orthopedic locking screw comprising: a shaft extending along an axis between a first end and a second end, the first end sized to be received in the threaded bore; a casing having a first end proximate the first end of the shaft and a second end proximate the second end of the shaft, the casing secured to an outer surface of the shaft such that during securing the orthopedic locking screw through the threaded bore of the orthopedic implant the casing is rotationally and axially fixed around the outer surface of the shaft and prevented from slipping radially relative thereto; a deformable thread disposed along an outer surface of the casing, wherein the deformable thread is configured to deform when engaged with a complementary internal thread feature of the threaded bore as the orthopedic locking screw is screwed through the threaded bore of the orthopedic implant; and a forward external thread disposed on the shaft between the first end of the casing and the first end of the shaft, wherein the forward external thread has a pitch that is different from a pitch of the deformable thread of the casing. ### Claim 20 An orthopedic locking screw configured to be secured through a bore, provided with an engagement feature, of an orthopedic implant, the orthopedic locking screw comprising: a shaft having projections disposed on an outer surface of the shaft; and a casing secured to the outer surface of the shaft such that during securing the orthopedic locking screw through the bore of the orthopedic implant the casing is rotationally and axially fixed around the outer surface of the shaft and prevented from slipping radially relative thereto, wherein the casing is formed of a deformable material configured to deform when engaged with the engagement feature as the orthopedic locking screw is secured through the bore of the orthopedic implant, wherein the projections and the casing are alternately arranged on the outer surface of the shaft, such that the projections and the casing together form a thread-like feature along the shaft.