(12) United States Patent
`Sohngen
`
`(10) Patent N0.2
`(45) Date of Patent:
`
`US 8,092,454 B2
`Jan. 10, 2012
`
`US008092454B2
`
`,
`
`,
`
`aWes
`
`(54) FIXATION INSTRUMENT FOR TREATINGA
`BONE FRACTURE
`
`(76) Inventor: Gary W. Sohngen, San Pedro, CA (US)
`
`( * ) Notice:
`
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U-S-C- 154(1)) by 166 days-
`
`-
`
`-
`
`(21) Appl. No.: 11/078,750
`
`(22) Filed:
`
`Man 11 2005
`’
`
`(65)
`
`.
`.
`.
`Pm" Pubhcatlon Data
`
`US 2005/0203510A1
`
`Sep. 15, 2005
`
`Related US. Application Data
`.
`.
`.
`.
`(60) Provisional application No. 60/552,229, ?led on Mar.
`11, 2004-
`(51) Int- Cl‘
`(2006-01)
`A61B 17/58
`(52) U..S. Cl. ...... .... ...... ... ......................... .. 606/67, 606/62
`(58) Field of Classi?cation Search .................. .. 606/62,
`606/64, 65, 66, 67
`See appl1cat1on ?le for complete search history.
`References Cited
`
`(56)
`
`JP
`
`gulrham it 81
`2
`,
`,
`y G et a .
`5,074,882 A 12/1991 Grammont et a1.
`5,122,141 A
`6/1992 S'
`t l.
`5,127,913 A
`7/1992 {$518253 33
`5,176,681 A
`1/1993 LaWes et al.
`2 13/
`Ehapman et a1~
`5,458,600 A “M995 Stapen et a1‘
`5,489,284 A
`2/1996 James et al.
`5,505,733 A
`4/1996 Justin et al.
`5,505,734 A
`4/1996 Caniggia et a1.
`5,549,610 A
`8/1996 Russell et a1.
`5,569,249 A 10/1996 James et al.
`5,620,445 A
`4/1997 Brosnahan et al.
`5,653,709 A
`8/1997 Frigg
`5,658,287 A
`8/1997 Hofmann et al.
`5,704,939 A
`1/1998 Justin
`5,766,174 A
`@1998 Perry
`t 1.
`5,855,579 A
`1/1999 J
`5,928,235 A
`7/1999 1:22;; e a
`5,935,127 A
`8/1999 B d
`6,004,324 A 0/1999 Gzlrlregt a1‘
`6,106,528 A
`8/2000 Durham et a1.
`(Continued)
`FOREIGN PATENT DOCUMENTS
`9066061
`3/l997
`(C t.
`d)
`on “me
`Primary Ex (1min er i Nicholas Woodall
`(74) Attorney, Agent, or Firm — Burgess LaW Ol?ce, PLLC
`
`U.S. PATENT DOCUMENTS
`2,518,019 A
`8/1950 Kane
`3,433,220 A
`3/1969 Zickel
`4,622,959 A 11/1986 Marcus
`4,776,330 A 10/1988 Chapman etal.
`4,805,607 A
`2/1989 Engelhardt et a1.
`4,827,917 A
`5/1989 Brum?eld
`4,875,475 A 10/1989 Comte et a1.
`4,877,019 A 10/1989 Vives
`4,946,459 A
`8/1990 Bradshaw et al.
`4,978,349 A 12/1990 Frigg
`
`ABSTRACT
`(57)
`A ?xation instrument for treating a bone fracture including a
`bone screW and a nail, Wherein the bone screW extends
`through an opening in the head or proximal end of the nail. A
`movable insert is disposed Within a chamber located at the
`proximal end of the nail. The insert engages the bone screW to
`prevent rotation thereof once the bone screW is placed in
`position.
`
`20 Claims, 7 Drawing Sheets
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`l L_.._____£ }_____-_________________________L_1
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`r 1——-r
`:
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`r
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`1'"
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`ZIMMER 1004
`Page 1
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`

`
`US 8,092,454 B2
`Page 2
`
`US. PATENT DOCUMENTS
`6,228,086
`B1
`5/2001
`Wahl et a1.
`6,235,031
`B1 *
`5/2001
`Hodgeman et a1. ........... .. 606/64
`Friedl
`6,261,290
`B1
`7/2001
`Fujiwara
`6,406,477
`B1
`6/2002
`6,562,042
`B2 *
`5/2003
`6,648,889
`B2 11/2003
`6,926,719
`B2 *
`8/2005
`7,306,600
`B2 * 12/2007
`
`Nelson .......................... .. 606/62
`Bramlet et a1.
`Sohngen et a1. .............. .. 606/64
`606/ 53
`
`2001/0012939 A1* 8/2001 Wahl et a1. .................... .. 606/67
`2001/0034523 A1* 10/2001 Nelson ....... ..
`.. 606/62
`2002/0156473 A1 * 10/2002 Bramlet et a1. .
`.. 606/62
`2003/0074000 A1 *
`4/2003 Roth et a1. .................... .. 606/62
`
`FOREIGN PATENT DOCUMENTS
`WO 94/13219
`6/1994
`W0
`WO 96/35387
`11/1996
`W0
`* cited by examiner
`
`ZIMMER 1004
`Page 2
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`US. Patent
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`Jan. 10, 2012
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`Sheet 1 of7
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`Jan. 10, 2012
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`Sheet 2 of7
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`Jan. 10, 2012
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`Sheet 3 of7
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`US 8,092,454 B2
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`122 A
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`Fig-8A
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`Jan. 10, 2012
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`Sheet 4 of7
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`Jan. 10, 2012
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`Sheet 5 of7
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`Jan. 10, 2012
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`Jan. 10, 2012
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`Sheet 7 of7
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`US 8,092,454 B2
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`[Fig- 14
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`116
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`114
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`Fig-15A
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`US 8,092,454 B2
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`1
`FIXATION INSTRUMENT FOR TREATING A
`BONE FRACTURE
`
`CROSS-REFERENCE TO RELATED
`APPLICATIONS
`
`This application claims the bene?t of US. Provisional
`Application No. 60/552,229, ?led Mar. 11, 2004.
`
`BACKGROUND OF THE INVENTION
`
`1. Field of the Invention
`The present invention relates generally to a ?xation instru
`ment for treating bone fractures. More speci?cally, a nail and
`bone screW combination used to treat a fracture of the femur
`including trochanteric, intertrochanteric and femoral neck
`fractures.
`2. Background of the Invention
`Orthopedic ?xation systems used for stabilizing a fracture
`often include an internal ?xation device, typically an elon
`gated implant such as a nail, screW or pin, inserted into the
`intramedullary canal of the bone to stabilize the fracture and
`promote healing. Such ?xation systems are often used With a
`fracture of the femur. The femur generally includes an elon
`gated shaft, a ball shaped head that ?ts into the hip socket and
`a neck connecting the ball to the shaft. The shaft also includes
`a greater trochanter and a lesser trochanter.
`Typically, the nail is inserted in the marroW canal of the
`bone and is positioned to span the fracture. Nails are also used
`to treat fractures of the neck, head, intertrochanter, subtro
`chanteric, pathologic and certain ipsilateral shaft and neck
`fractures of the femur. For example, if the neck of the femur
`sustains a fracture a bone screW inserted through an aperture
`in the nail spans the fracture and threadably engages the
`femoral head.
`Typically, the aperture in the end of the nail is a smooth
`bore in Which the bone screW rotates as it threadably engages
`the femoral head. Once the bone screW is suitably tightened,
`it is left in place during the healing process. Bone screW
`migration is one problem that may occur during the healing
`process. Speci?cally, during loading or movement of the
`femur, the bone screW may migrate or loosen, thus creating a
`risk of failure at the fracture. Accordingly, there is in need for
`a ?xation instrument that resists bone screW migration and
`rotation.
`
`SUMMARY OF THE INVENTION
`
`45
`
`Accordingly, the present invention is a ?xation instrument
`including a bone nail and bone screW combination for use in
`repairing a bone fracture. The bone nail extends Within the
`shaft portion of a bone such as a femur. An opening in the head
`or proximal end of the nail receives a bone screW that, in the
`case of a femoral neck fracture, extends into the femoral head.
`In accordance With an aspect of the present invention, a
`locking insert disposed Within the nail engages the bone
`screW and prevents rotation thereof. Further areas of applica
`bility of the present invention Will become apparent from the
`detailed description provided hereinafter. It should be under
`stood that the detailed description and speci?c examples,
`While indicating the preferred embodiment of the invention,
`are intended for purposes of illustration only and are not
`intended to limit the scope of the invention.
`
`50
`
`55
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`60
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`BRIEF DESCRIPTION OF THE DRAWINGS
`
`FIG. 1 is a diagrammatic front vieW of a ?xation instrument
`according to the present invention shoWn implanted Within a
`femur.
`
`65
`
`2
`FIG. 2 is an enlarged front vieW of the proximal end of the
`?xation instrument according to the present invention With
`portions removed for clarity and illustration.
`FIG. 3 is a cross-sectional vieW of the bone screW shoWn in
`FIG. 2 taken along lines 3-3.
`FIGS. 4A-4E are various vieWs of an insert for use With the
`?xation instrument according to the present invention.
`FIG. 5 is a side vieW of a locking ring for use With the
`?xation instrument according to the present invention.
`FIG. 6 is a side vieW of a cap for use With the ?xation
`instrument according to the present invention.
`FIG. 7 is a front vieW of an alternative embodiment of a
`?xation instrument according to the present invention With
`portions removed for clarity and illustration.
`FIGS. 8A-8D are various vieWs of an alternative embodi
`ment of an insert for use With the ?xation instrument accord
`ing to the alternative embodiment of FIG. 7.
`FIG. 9 is a front vieW of an additional alternative embodi
`ment of a ?xation instrument according to the present inven
`tion With portions removed for clarity and illustration.
`FIGS. 10A-10D are various vieWs of the additional alter
`native embodiment of an insert for use With the ?xation
`instrument according to the alternative embodiment of FIG.
`9.
`FIG. 11 is a side vieW of a cap for use With the ?xation
`instrument according to the alternative embodiment of FIG.
`9.
`FIG. 12 is a front vieW of a further alternative embodiment
`of a ?xation instrument according to the present invention.
`FIG. 13 is a front vieW, With portions removed for clarity, of
`the cap and insert assembly used in connection With the
`?xation instrument according to the embodiment of FIG. 12.
`FIG. 14 is a side vieW of the further alternative embodiment
`of the ?xation instrument shoWn in FIG. 12.
`FIG. 15 is a side vieW of the cap and insert assembly shoWn
`in FIG. 12 used in connection With the ?xation instrument
`according to the embodiment of FIG. 12, With FIG. 15A being
`a bottom vieW of the insert assembly of FIG. 15.
`
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`DETAILED DESCRIPTION OF THE INVENTION
`
`FIG. 1 shoWs a ?xation instrument, seen generally at 20,
`according to one embodiment of the present invention placed
`in an assembled condition Within a bone 1 0, illustrated here as
`a femur. The ?xation instrument 20 includes a nail member 22
`formed of a metallic alloy, such as a titanium alloy. The nail
`member 22 includes a distal end 18 and a proximal end 24.
`The distal end 18 typically includes at least one transverse
`aperture that receives a bone screW 1 6 used to ?x the distal end
`18 of the nail member 22 in place in the bone 10. The proxi
`mal end 24 includes a trailing or rear edge 26.
`Turning noW to FIGS. 2-6, a passageWay 28 extends lon
`gitudinally through the nail member 22 betWeen the proximal
`end 24 and the distal end 18. The passageWay 28 receives
`insertion and extraction instrumentation, such as a guide Wire
`(not shoWn), used to position the nail member 22 Within the
`bone 10. Typically, the distal end 18 of the nail member 22 is
`inserted into the bone 10 ?rst and folloWs the path of the guide
`Wire.
`The proximal end 24 includes an aperture 30 extending
`through the proximal end 24 in a direction that is typically
`angled With respect to the longitudinal axis 25 of the nail
`member 22. A bone screW 32 having a threaded portion 34 on
`one end thereof extends through the aperture 30 such that the
`threaded portion 34 engages the femoral head 12 for sliding
`compression of a femoral neck 14 or intratrochanteric frac
`ture.
`
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`US 8,092,454 B2
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`3
`An insert 36 having a distal end 38 and a proximal end 40
`is disposed Within a chamber 42 located in the proximal end
`24 of the nail member 22. The insert 36 further has a pair of
`tabs or guide/locating members 44 that extend radially out
`Ward from the body of the insert 36. The tabs or guide/
`locating members 44 cooperate With a pair of grooves or
`channels 46 that extend longitudinally along the sideWalls 48
`of the chamber 42. The proximal end 24 of the nail member 22
`includes an opening 50 at the trailing or rear edge 26 of the
`nail member 22. The opening 50 provides access to the cham
`ber 42.
`The insert 36 further includes a loWer surface 52 having a
`pair of locking projections 54 extending longitudinally doWn
`Ward/outWard from the loWer surface 52. The insert 36 is
`placed in the chamber 42 through the opening 50, such that
`the tabs or guide/locating members 44 are received in the
`grooves or channels 46 located in the sideWalls 48 of the
`chamber 42. Accordingly, the insert 36 is slidably received
`and prevented from rotating in the chamber 42. The loWer
`surface 52 of the insert 36 extends or is oriented at an angle
`that is substantially the same as the angle of the aperture 30
`extending through the proximal end 24 of the nail member 22.
`As set forth beloW, the insert 36 engages the bone screW 32
`disposed in the aperture 30 in the nail member 22.
`The bone screW 32 further includes a plurality of longitu
`dinally extending grooves 56 located on the outer surface 58
`of the bone screW 32. The grooves 56 are of a siZe and shape
`that are complementary to the locking projections 54 located
`on the loWer surface 52 of the insert 36. As seen in FIG. 2,
`When the insert 36 travels longitudinally in the chamber 42 it
`reaches a point Wherein the loWer surface 52 and locking
`projections 54 of the insert 36 are adjacent the bone screW 32.
`Since the purpose of the locking projections 54 is to engage
`the grooves 56 to secure and prevent rotation of the bone
`screW 32 it may be necessary to rotate the bone screW 32
`slightly to align the grooves 56 of the bone screW 32 With the
`locking projections 54 of the insert 36. Once properly
`aligned, the insert 36 is driven further Within or into the
`chamber 42 until the loWer surface 52 of the insert 36 engages
`the outer surface 58 of the bone screW 32 and the locking
`projections 54 of the insert 36 extend into the grooves 56 of
`the bone screW 32.
`A locking ring 60 controls the position of the insert 36
`Within the chamber 42. The locking ring 60 has a plurality of
`threads 62 disposed about the outer surface of the locking ring
`60. The locking ring 60 threadably engages a plurality of
`threads 64 disposed on the sideWalls 48 of the chamber 42. As
`shoWn in FIG. 5, the locking ring 60 includes a post portion 66
`located on or forming a portion of the loWer surface 68 of the
`locking ring 60. The post portion 66 further includes an
`inWardly projecting ?nger 70. The post portion 66 may be
`formed as an annular member that extends all the Way around
`the loWer surface 68 or it may be formed as a plurality of
`individual post members spaced about the loWer surface 68 of
`the locking ring 60.
`The inWardly projecting ?nger 70 cooperates With a retain
`ing member 72 formed on the upper surface 74 of the proxi
`mal end 40 of the insert 36. The retaining member 72 further
`includes an annular member 76 having an outWardly extend
`ing lip 78. Accordingly, the locking ring 60 is placed on or
`attached to the insert 36 using a snap or press ?t arrangement.
`Speci?cally, the locking ring 60 is placed on the upper surface
`74 of the insert 36 and a su?icient force is exerted on the
`locking ring 60 to de?ect the inWardly projecting ?ngers 70
`and correspondingly the post portion 66 outWard over the
`annular member 76. Upon clearing the annular member 76,
`the ?ngers 70 snap back into place Whereby they engage the
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`underside of the lip 78 and rotatably secure the locking ring
`60 to the insert 36. It should be understood that such an
`arrangement enables the locking ring 60 to rotate about the
`longitudinal axis 37 of the insert 36 While remaining attached
`to the insert 36.
`The locking ring 60 has an aperture or opening 80 having a
`hexagonal shape that functions as a drive portion of the lock
`ing ring 60. Accordingly, a suitable tool, such as a T-handle
`hexagonal Wrench, may be inserted into the opening 80 to
`rotate or turn the locking ring 60. This arrangement enables
`the insert 36 to be placed in the chamber 42 prior to the nail
`member 22 being inserted into the bone. Other con?gurations
`may function or comprise the drive portion, including putting
`a slot in the upper surface of the locking ring 60 that receives
`a driving tool such as a screWdriver.
`The insert 36 is placed Within the chamber 42 such that the
`tabs or guide/ locating members 44 engage the grooves/chan
`nels 46 located in the sideWalls 48 of the chamber 42. Since
`the overall outer diameter of the insert 3 6 is less than the inner
`diameter of the threads 64 in the sideWalls 48 of the chamber
`42, the insert 36 slides freely in the longitudinal direction and
`is constrained against rotation by the tabs or guide/locating
`members 44. As shoWn, the locking ring 60 is rotatably
`attached to the insert 36. Accordingly, When the threads 62 on
`the locking ring 60 engage the threads 64 in the sideWall 48 of
`the chamber 42 and When the locking ring 60 is rotated by a
`suitable tool, the locking ring 60 moves the insert 36 longi
`tudinally Within the chamber 42. As set forth above, the insert
`36 and locking ring 60 combination is placed Within the
`chamber 42 prior to inserting or installing the nail member 22
`in the bone 10.
`In use, once the nail member 22 is installed in the bone 10,
`the bone screW 32 is placed in and extends through the aper
`ture 30 Whereby it engages the femoral head 12. After tight
`ening the bone screW 32 to compress the fracture, a suitable
`tool engages and rotates the locking ring 60 to move the insert
`36 doWnWardly Within the chamber 42 until the locking pro
`jections 54 engage the grooves 56 on the outer surface 58 of
`the bone screW 32. If necessary, it may be required to rotate
`the bone screW 32 slightly in order to have the locking pro
`jections 54 line up With the grooves 56. Once the insert 36 and
`bone screW 32 are properly aligned, tightening the locking
`ring 60 maintains engagement betWeen the locking projec
`tions 54 and the grooves 56 and prevents rotation of the bone
`screW 32.
`After tightening the locking ring 60, the opening 50 at the
`trailing or rear edge 26 of the nail member 22 is closed by a
`cap 82 threadably received in the chamber 42. The cap 82
`includes a threaded post 84, the threads being of a suitable
`siZe and con?guration to engage the threads 64 located in the
`sideWall 48 of the chamber 42. The cap 82 further includes a
`socket 85 suitable for receiving a driving tool to rotate and
`secure the cap 82 in the opening 50.
`It should be understood that the insert 36 and locking ring
`60 both have longitudinal passageWays 86, 88 that alloW the
`nail member 22 to be inserted Within the bone 10 and folloW
`a guide Wire (not shoWn), With both the insert 36 and locking
`ring 60 installed or positioned Within the chamber 42 of the
`nail member 22. Accordingly, the present invention enables
`the insert 36 to be pre-positioned or placed in the nail member
`22 prior to installation, thus eliminating the need and di?i
`culty of having to thread the insert 36 in place after the nail
`member 22 is placed Within the bone 10.
`FIGS. 7-8 disclose an additional embodiment of a ?xation
`instrument 20, according to the present invention. Speci?
`cally, the loWer surface 110 of the insert 36 has an arcuate
`surface having a shape complementary to the outer diameter
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`US 8,092,454 B2
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`5
`of the bone screw 32. This embodiment does not use the
`locking projections of the previous embodiment, nor does the
`bone screW 32 have longitudinal grooves contained therein.
`The arcuate shape of the loWer surface 110 creates a greater
`amount of surface area of the insert 36 that contacts the outer
`surface 58 of the bone screW 32. Thus, tightening the locking
`ring 60 provides a suf?cient force to create friction ?t betWeen
`the insert 36 and the bone screW 32 that prevents rotation of
`the bone screW 32 Within the aperture 30 of the nail member
`22.
`FIG. 8A further illustrates an alternative embodiment of a
`rotatable connection betWeen the locking ring 60 and the
`insert 36. As shoWn therein, the locking ring 60 includes a
`doWnWardly projecting ?nger 120 having an inWardly bev
`eled surface 122 and a lip 124. The insert 36 includes a
`inWardly extending ?ange 126. As With the previous embodi
`ment, the locking ring 60 is rotatably attached to the insert 36
`using a snap or press ?t arrangement. Speci?cally, applying a
`force to the locking ring 60 causes the beveled surface 122 of
`the doWnWardly projecting ?nger 120 to engage the inWardly
`extending ?ange 126 and de?ect the ?nger 120 radially
`inWard until the lip 124 of the locking ?nger 120 clears the
`?ange 126 and Whereby the locking ?nger 120 snaps out
`Wardly and the lip 124 engages the underside of the ?ange 126
`to rotatably secure the locking ring 60 to the insert 36.
`FIGS. 9-11 shoW an alternative embodiment of a ?xation
`instrument 20 according to the present invention. As shoWn in
`FIG. 9, the proximal end 24 of the nail member 22 has an
`additional aperture 90 for receiving a second bone screW 92.
`As set forth in the previous embodiment, the insert 94
`includes tabs or guide/ locating members 96 that are received
`in the grooves/channels 46 located on the sidewalls 48 of the
`chamber 42 Whereby the insert 94 is slidably ?t Within the
`chamber 42. The insert 94 has an arcuate loWer surface 97
`having a degree of curvature corresponding to the radius of
`the bone screW 32. Accordingly, as set forth above, rotating
`the locking ring 100 causes the arcuate loWer surface 97 of the
`insert 36 to engage the outer surface 58 of the bone screW 32
`to prevent rotation of the bone screW 32 Within the aperture 30
`of the nail member 22. The insert 94 also includes an aperture
`98 extending at an angle With respect to the longitudinal axis
`of the insert 94 for receiving the second bone screW 92. The
`aperture 98 is elongated in the longitudinal direction to alloW
`for travel of the insert 36 Within the passageWay 28 Without
`engaging the second bone screW 92.
`A cap 102 including an elongated tab or locking projection
`104 is used to secure the second bone screW 92. When the cap
`102 is inserted into the opening 50 on the trailing or rear edge
`26 of the nail member 22, the elongated tab or locking pro
`jection 104 engages the second bone screW 92 to prevent
`rotation thereof via a frictional ?t. In addition, the elongated
`tab or locking projection 104 may include and engagement
`portion Which sits Within a groove located on the second bone
`screW 92, as With the previous embodiments, to further pre
`vent rotation of the second bone screW 92. This arrangement
`prevents rotation of both the ?rst and second bone screWs 32,
`92 With respect to the nail member 22.
`FIGS. 12-15 shoW a further alternative embodiment of a
`?xation instrument 20 according to the present invention,
`Wherein the insert 36 has a loWer surface formed of a pair of
`doWnWardly extending ?ngers 114. Each of the doWnWardly
`extending ?ngers 114 has an arcuate engagement surface 116
`having a curvature or radius of curvature complementary to
`the diameter of the bone screW 32. The arcuate engagement
`surfaces 116 form the loWer or contact surface of the insert 36.
`Accordingly, each of the ?ngers 114 engages the bone screW
`32 to secure or prevent rotation of the bone screW 32 Within
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`the aperture 30. The insert 36 is positioned in and secured
`Within the chamber 42 in a manner similar to the ?rst embodi
`ment. As With the previous embodiments, the locking ring 60
`is used to position and secure the insert 36 Whereby the
`arcuate engagement surfaces 116 of the ?ngers 114 engage
`the bone screW 32 and prevent rotation thereof.
`It should be understood that the mounting relationship
`betWeen the locking ring 60 and the insert 36 is one that
`enables the locking ring 60 to turn or rotate freely on the insert
`36. In the case of the disclosed embodiments, the insert 36
`travels longitudinally Within the grooves or channels 46
`located in the sideWalls 48 of the chamber 42. Thus, the
`apparatus and corresponding components forming the snap or
`press ?t mounting relationship betWeen the locking ring 60
`and the insert 36, as shoWn in the disclosed embodiments,
`including the inWardly projecting ?nger and lip on the annular
`member, may be positioned on either the respective locking
`ring 60 or insert 36; i.e., the ?nger may be on the insert 36 or
`the locking ring 60 as long as the complementary component,
`the lip, is on the corresponding member.
`Thus, it Will be seen that the objects of the invention have
`been fully and effectively accomplished. It Will be realiZed,
`hoWever, that the foregoing speci?c embodiments have been
`shoWn and described for the purposes of illustrating the func
`tional and structural principles of the invention and is subject
`to change Without departure from such principles. Therefore,
`this invention includes all modi?cations encompassed Within
`the scope of the folloWing claims.
`
`What is claimed is:
`1. A ?xation instrument for treating a bone fracture com
`prising:
`a nail member, said nail member having a longitudinal
`axis, a distal end and a proximal end, said proximal end
`having an aperture extending therethrough and said nail
`member having a chamber located in said proximal end;
`an insert having a longitudinal axis, said insert positioned
`and constrained against rotation about said longitudinal
`axis of said insert Within said chamber;
`a bone screW, having a threaded portion, said bone screW
`extending through said aperture;
`a locking ring received in said chamber and engaging said
`insert, said locking ring operative to secure said insert
`Within said chamber; and
`said insert having a distal end and a proximal end, a con
`cave loWer surface located at said distal end of said
`insert, said concave loWer surface being that portion of
`the insert spaced farthest from the proximal end and
`engaging a convex surface of said bone screW, said con
`vex surface complementary to said concave loWer sur
`face of said insert, When said bone screW extends
`through said aperture.
`2. A ?xation instrument for treating a bone fracture as set
`forth in claim 1 Wherein said nail member has an opening
`adjacent a rear edge of said nail member to provide access to
`said chamber.
`3. A ?xation instrument for treating a bone fracture as set
`forth in claim 1 including said chamber having a plurality of
`threads located on an inner surface thereof;
`said locking ring having a plurality of threads located on an
`outer surface thereof, said threads on said locking ring
`complementary to said threads on said inner surface of
`said chamber; and
`said locking ring having a drive portion, Whereby a suitable
`tool engages said drive portion and is used to move said
`locking ring.
`
`ZIMMER 1004
`Page 12
`
`

`
`US 8,092,454 B2
`
`7
`4. A ?xation instrument for treating a bone fracture as set
`forth in claim 1 including said concave loWer surface having
`a shape complementary to an outer diameter of said bone
`screW.
`5. A ?xation instrument for treating a bone fracture as set
`forth in claim 4 including said aperture extending through
`said nail member at an angle With respect to the longitudinal
`axis of said nail member; and
`said loWer surface extending at an angle substantially the
`same as the angle of said aperture.
`6. A ?xation instrument for treating a bone fracture com
`prising:
`a nail member, said nail member having a longitudinal
`axis, a distal end and a proximal end, said proximal end
`having an aperture extending therethrough and said nail
`member having a chamber located in said proximal end;
`an insert adapted to be positioned Within said chamber and
`having a loWer surface, said loWer surface operative to
`contact a bone screW extending through said aperture;
`a locking ring received in said chamber and engaging said
`insert, said locking ring operative to secure said insert
`Within said chamber;
`a locking projection located on said loWer surface of said
`insert; and
`said bone screW having a longitudinally axis and having a
`plurality of longitudinal extending grooves, said
`grooves extending substantially parallel to said longitu
`dinal axis of said bone screW on an outer surface of said
`bone screW Wherein said locking projection is located in
`one of said grooves When said loWer surface contacts
`said bone screW.
`7. A ?xation instrument for treating a bone fracture as set
`forth in claim 6 including said aperture extending through
`said nail member at an angle With respect to the longitudinal
`axis of said nail member; and
`said loWer surface extending at an angle substantially the
`same as the angle of said aperture.
`8. A ?xation instrument for treating a bone fracture as set
`forth in claim 6 Wherein each of said insert and said locking
`ring have longitudinal passageWays extending therethrough,
`Wherein said longitudinal passageWay extending through said
`insert terminates at said loWer surface.
`9. A ?xation instrument for treating a bone fracture as set
`forth in claim 6 Wherein said locking ring is rotatably con
`nected to said insert.
`10. A ?xation instrument for treating a bone fracture as set
`forth in claim 9 Wherein said locking ring includes a post
`portion having an inWardly projecting ?nger; and
`said insert having a retaining member located on a distal
`end thereof, said retaining member including an out
`Wardly extending lip Wherein said locking ?nger
`engages said lip to rotatably secure said locking ring to
`said insert.
`11. A ?xation instrument for treating a bone fracture as set
`forth in claim 6 including a cap, said cap operative to close
`said opening located at said rear edge of said nail member.
`12. A ?xation instrument for treating a bone fracture as set
`forth in claim 6 Wherein said loWer surface is an arcuate
`surface.
`13. A ?xation instrument for treating a bone fracture com
`prising:
`a nail member, said nail member having a longitudinal
`axis, a distal end and a proximal end, said proximal end
`having an aperture extending therethrough at an angle
`With respect to the longitudinal axis of said nail member
`and said nail member having a chamber located in said
`proximal end;
`
`20
`
`25
`
`30
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`8
`
`a bone screW;
`an insert adapted to be positioned Within said chamber, said
`insert having a proximal end and a distal end, said distal
`end terminating at said loWer surface, said loWer surface
`extending at an angle substantially the same as the angle
`of said aperture extending through said nail member and
`engaging said bone screW When said bone screW extends
`through said aperture;
`a locking ring received in said chamber and engaging said
`insert, said locking ring operative to secure said insert
`Within said chamber;
`said nail member having a second aperture extending
`therethrough for receiving a bone screW; and
`said insert having an aperture therein extending at an angle
`With respect to a longitudinal axis of said insert, said
`angle substantially the same as the angle of said second
`aperture extending through said nail member, said aper
`ture for receiving a bone screW.
`14. A ?xation instrument for treating a bone fracture as set
`forth in claim 13 Wherein said insert includes a longitudinal
`passageWay extending through said insert;
`said locking ring having a longitudinal passageWay extend
`ing through said locking ring; and
`a cap, said cap having an elongated locking projection, said
`elongated locking projection extending through said
`passageWay in said locking ring and into said passage
`Way in said insert, said elongated locking projection
`operative to engage a bone screW extending through said
`aperture in said insert.
`15. A ?xation instrument for treating a bone fracture as set
`forth in claim 14 Wherein said locking ring is rotatably con
`nected to said insert.
`16. A ?xation instrument for treating a bone fracture com
`prising:
`a nail member, said nail member having a longitudinal
`axis, a distal end and a proximal end, said proximal end
`having an aperture extending therethrough at an angle
`With respect to said longitudinal axis, said nail member
`having a chamber located in said proximal end, said
`chamber having a plurality of threads located on an inner
`surface thereof and at least one groove located in said
`chamber;
`an insert having a distal end and a proximal end adapted to
`be positioned Within said chamber, said insert having at
`least one locating member, said locating member coop
`erating With said groove located in said chamber, said
`insert having a concave loWer surface forming said distal
`end, said distal end and correspondingly said concave
`loWer surface operative to engage a convex surface of
`said bone screW When said bone screW extends through
`said aperture; and
`a locking ring received in said chamber and engaging