[19]
`United States Patent
`
`Haberman
`[45] Date of Patent:
`Mar. 30, 1999
`
`[11] Patent Number:
`
`5,888,216
`
`U8005888216A
`
`[54] PROSTHESIS LINER FOR BELOW-KNEE
`AMPUTEES
`
`[76]
`
`Inventor: Louis J. Haberman, 1 Arden Rd.,
`-
`Denvme’ NJ’ 07834
`
`[21] Appl. No.: 738,278
`
`[22]
`
`Filed:
`
`Oct. 25, 1996
`
`Related US. Application Data
`
`[63]
`
`Continuation—in—part of Ser. No. 617,392, Mar. 18, 1996,
`abandoned.
`
`...................................... 623/57
`5,263,990 11/1993 Handal
`5,314,497
`5/1994 Fay et a1.
`.
`623/34
`
`12/1994 Lenze et al.
`.............................. 623/34
`5,376,131
`3283::
`3133; Eagle
`2/239
`,
`,
`an1a ..........................................
`5,662,715
`9/1997 Slemker
`.................................... 623/36
`
`FOREIGN PATENT DOCUMENTS
`
`France ..................................... 623/57
`712847 10/1931
`
`391185
`3/1924 Germany
`623/57
`
`609573
`2/1935 Germany
`623/57
`53—31750
`3/1978
`Japan ....................................... 623/33
`WO 95/31160 “/1992 WIPO‘
`W0 95/05792
`3/1995 WIPO .
`
`[51]
`Int. Cl.6 ........................................................ A61F 2/78
`[52] U..S. Cl.
`................................................................ 623/36
`[58] Fleld of Search .................................. 623/32—37, 57,
`602/62
`
`OTHER PUBLICATIONS
`Kubota et al., Photokilling of T—24 human bladder cancer
`cells with titanium dioxide, Br. J Cancer, 70’ 1107_1111
`1994.
`
`[56]
`
`References Cited
`UHS PATENT DOCUMENTS
`
`Primary Examiner—David H. Willse
`Attorney, Agent, or Flrm—Paul N. KatZ
`
`2,244,871
`3,322,873
`3,377,416
`3,600,717
`3,957,713
`4,300,245
`4,413,359
`498229371
`49087037
`4,923,474
`5’007’937
`5,163,965
`5,226,918
`5,246,464
`
`6/1941 Guinzburg .................................... 2/59
`5/1967 Hitchcock ............................... 264/222
`4/1968 Kandel
`.................................... 264/222
`8/1971 McKeehan .
`5/1976 Jeram et a1.
`............................ 524/703
`11/1981 Saunders ............. 623/35
`
`11/1983 Akiyama et a1
`. 623/36 X
`
`4/1989 Jolly et a1.
`~~~~~ 623/32
`
`3/1990 R055 ~~~~~~~~~~~~~~~~~~~~ 623/32
`
`5/1990 mass” et al‘
`“““ 623/33
`
`4/1991 FIShman et al’ "
`""" 623/34
`11/1992 Rasmusson et a1.
`..... 623/36
`
`
`7/1993 Silagy et a1. ........... 623/32
`9/1993 Sabolich .................................... 623/33
`
`[57]
`A
`
`ABSTRACT
`.
`.
`b 1
`k
`f
`1.
`.
`h
`Pro“ 6.515 1““ or 90"“ “e? amputees coml’mmg a
`polymer liner, such as Silicone, incorporating a pre-flexed
`shape haVIHg an angle at the knee selected from 20 to 60
`degrees, at
`least one thickened upper silicone band, an
`appropriate anatomical shape and taper and a flexible con-
`nector piece at the bottom portion of the liner adapted for
`connection to a walking piece. An anti-bacterial agent is
`added to the liner to suppress the over-growth of bacteria
`that may form between the liner and the residuum
`'
`
`12 Claims, 3 Drawing Sheets
`
`
`
`Otto Bock
`
`Exhibit 2002
`
`Page1
`
`Otto Bock Exhibit 2002 Page 1
`
`

`

`US. Patent
`
`Mar. 30, 1999
`
`Sheet 1 0f3
`
`5,888,216
`
`FIGURE 1
`
`
`FIGURE 2
`
`Otto Bock
`
`Exhibit 2002
`
`PageZ
`
`Otto Bock Exhibit 2002 Page 2
`
`

`

`US. Patent
`
`Mar. 30, 1999
`
`Sheet 2 0f 3
`
`5,888,216
`
`FIGURE 3
`
`FIGURE 4
`
`1’19
`
`41”
`
`
`
`‘III/’9’???all/g;
`
`FIGURE 5
`
`FIGURE 7
`
`Otto Bock
`
`Exhibit 2002
`
`Page 3
`
`Otto Bock Exhibit 2002 Page 3
`
`
`
`

`

`US. Patent
`
`Mar. 30, 1999
`
`Sheet 3 0f3
`
`5,888,216
`
`50
`
`/
`
`58
`
` FIGURE 6
`
`Otto Bock
`
`Exhibit 2002
`
`Page4
`
`Otto Bock Exhibit 2002 Page 4
`
`

`

`1
`PROSTHESIS LINER FOR BELOW-KNEE
`AMPUTEES
`
`CROSS REFERENCE TO RELATED PATENT
`APPLICATION
`
`This patent application is a continuation-in-part of US.
`patent application Ser. No. 08/617,392, filed Mar. 18, 1996,
`now abandoned, entitled “Prothesis Method and Device For
`Below-Knee Amputees” by Louis J. Haberman, and is
`incorporated by reference herein.
`FIELD OF THE INVENTION
`
`The invention generally relates to prosthesis devices and,
`in particular, the invention relates to a prosthesis device liner
`incorporating a preflexed angle at the knee.
`BACKGROUND OF THE INVENTION
`
`The prior art prosthesis utilizing a below-knee silicone
`liner is described in detail in various prosthetic journals. In
`1989, C. H. Fillauer, CPO, C. H. Pritham, CPO, and K. D.
`Fillauer, CPO, reported on “The Evolution and Develop-
`ment of the Silicone Suction Socket (3S) for Below-Knee
`Prostheses” in the Journal of Prosthetics and Orthotics. In
`1995, L. J. Haberman, CPO, R. A. Bedotto, CPO, LPT, and
`E. J. Colodney, MD, described the use of an injection-
`molded silicone liner with suspension tabs for below-knee
`amputees in the article entitled “Silicone Only Suspension”
`(SOS) in the Journal of Prosthetics and Orthotics.
`The prior art below-knee silicone designs are constructed
`either of fabric impregnated with silicone or with room
`temperature vulcanized (RTV) silicone. The fabric-type
`liner is conventionally laminated with a liquid silicone
`(RTV) under a vacuum-type system. These liners have the
`disadvantage that they are porous and harbor and promote
`the growth of bacteria. Further, the fabric silicone liner lacks
`durability when the thin silicone material
`is subject
`to
`abrasion during daily use since it rubs against the residuum
`(stump) which eventually uncovers the underlying fabric
`which can irritate the skin.
`
`Other RTV silicone liners have been disclosed in the prior
`art which are custom injection-molded. While these silicone
`liners are relatively non-porous and cannot harbor bacteria,
`they are inclined to be fragile, reducing their service life, and
`are also time-consuming to fabricate.
`Pre-fabricated injection-molded silicone liners are now
`available to the amputee in various sizes and styles. They are
`more durable as they are constructed of a heat-cured, two
`part silicone composition. They are constructed free of a
`fabric matrix and, thus, will not irritate the skin as the inner
`surface is rubbed away. All of these commercially available
`silicone liners are, however, generally tubular in shape,
`offering very little tapering towards the distal end. Such
`silicone liners are in a straight-line orientation (windsock
`shaped) and respond poorly to angular (flexion) changes to
`the knee. As an illustration, significant wrinkling of these
`straight-line silicone liners occur in the back of the knee
`when the user sits down. Heightened compression of the
`kneecap (patella) occurs which can irritate the skin overly-
`ing the kneecap. Straight-line oriented liners also tend to
`bias the knee joint to a straight position when the knee is
`flexed, i.e., the liner is under tension and it wants to restore
`itself to its straight molded position. Thus, the amputee must
`maintain a flexure pressure in order to keep the knee and
`prosthesis from extending to its straight position.
`Silicone liners typically utilize a hard, unyielding
`material, such as aluminum or polycarbonate as a shuttle
`
`10
`
`15
`
`20
`
`25
`
`30
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`5,888,216
`
`2
`
`screw housing (hereafter “umbrella”) for affixing the lower
`leg portion of the prosthesis. Rigid aluminum shuttle screw
`housings and rigid polycarbonate shuttle screw housings are
`not flexible and have limitations as to functional life and/or
`comfort to the amputee. Polycarbonate umbrellas may frac-
`ture and fail within months of initial use. Aluminum umbrel-
`
`las have no flexibility and cannot distort to comply with the
`naturally occurring movement of the residuum within the
`prosthetic socket.
`Prior art silicone liners also lack anatomical symmetry to
`the amputation limb which results in marked distortion of
`the silicone liner during naturally occurring changes in the
`position of the knee and residuum. The lack of anatomical
`symmetry results in a reduction of the naturally occurring
`range of motion (ROM) present in the human knee due to the
`wrinkling and bunching of the silicone material
`in that
`region. The lack of anatomical symmetry causes an uneven
`stretching of the silicone liner which may be harmful to the
`underlying tissues, be uncomfortable to wear, and can result
`in premature wearing and subsequent tearing of the silicone
`liner. Prior art silicone liners lack reinforcement at their
`
`in premature
`upper (proximal) edge which may result
`tearing, requiring early replacement of the silicone liner.
`Silicone liners also create conditions which increase the
`
`potential for growth of bacteria on the skin of the amputee.
`The silicone liner, which is a relatively impermeable
`material, tends to encourage the skin to be constantly moist
`from sweating. This condition creates the right environment
`for undesirable bacteria to proliferate on the residuum, thus
`making the amputee’s skin susceptible to invasion by patho-
`genic microorganisms. The constant moisture present when
`wearing a silicone liner and the occlusion from the liner
`which occurs to the amputee’s skin, increases the skin’s
`vulnerability to bacteriological infection.
`OBJECTS OF THE INVENTION
`
`An object of the invention is to provide a prosthesis
`device with a polymer liner incorporating a pre-flexed angle
`at the knee.
`
`Another object of the invention is to provide such a liner
`with at least one thickened silicone band toward the upper
`(proximal) edge of the liner.
`Another object of the invention is to provide such a liner
`with at least two thickened silicone bands toward the upper
`(proximal) edge of the liner.
`A further object of the invention is to provide a prosthesis
`with a liner having an appropriate anatomical shape and
`taper.
`A still further object of the invention is to provide a
`flexible connector piece for prosthesis suspension positioned
`at the bottom (distal) portion of the prosthesis device.
`Another object of the invention is to incorporate an
`anti-bacterial agent or agents into the liner which substan-
`tially suppresses the over-growth of bacteria between the
`liner and the residuum.
`
`Yet another object of the invention is to provide and
`incorporate a umbrella made of flexible material, such as
`silicone, at the distal end of the silicone liner for attaching
`a rod which is used as part of a prosthesis to enable the
`amputee to walk thereon.
`Other objects and the advantages of the invention will
`appear from the following description.
`SUMMARY OF THE INVENTION
`
`It has been discovered that the utilization of a prosthesis
`which incorporates a pre-flexed angle of from 20 to 60
`
`Otto Bock
`
`Exhibit 2002
`
`Page5
`
`Otto Bock Exhibit 2002 Page 5
`
`

`

`5,888,216
`
`3
`degrees at the knee region results in better comfort for the
`user and extends the service life of the prosthesis. The flexed
`angle of the present invention substantially reduces wrin-
`kling of the liner behind the knee when the knee is flexed.
`In addition, the kneecap (patella) is not overly compressed
`by the silicone material of the liner when the knee is flexed.
`Skin irritation, blister formation and discomfort to the back
`of the knee and the kneecap are thus substantially reduced
`when using the present
`invention. Also,
`the pre-flexed
`silicone liner permits far greater knee flexion for the ampu-
`tee then was possible with the prior art straight liners. This
`is important
`to the basic activities of daily living. This
`feature also is helpful in such circumstances as sitting for
`periods greater than 15 minutes, getting in and out of a car,
`sitting in a movie theater, avoiding the necessity for an aisle
`seat on an airplane and the like.
`A feature of the present invention is a thickened upper
`portion of the wall of the silicone liner which significantly
`reduces tearing of the silicone liner that most often occurs
`when donning and doffing it. The thickened upper portion of
`the silicone liner also creates a proximal radius which is
`helpful in reducing the incidence of shear to stress loading
`of the skin proximate thereto.
`Another feature is the pre-flexed angle which minimizes
`wrinkling behind the knee, increases the range of motion of
`the knee joint, and is more comfortable to wear when sitting.
`Another feature is an anatomical taper which achieves
`more uniform compression of the skin of the residuum.
`Still another feature is at least one proximal silicone band
`which reduces tearing, provides a radius to reduce skin
`shear, and improves the suction seal of the liner to the
`residuum.
`
`Still another feature of the present invention is at least two
`proximal silicone bands which reduce tearing, provide a
`radius to reduce skin shear, and improve the suction seal of
`the liner to the residuum. In addition the proximate end of
`the liner may be trimmed between the at least two silicone
`bands to reduce the length of the liner for improved comfort
`of the amputee without compromising the aforementioned
`features of the present invention.
`Another object of the invention is to incorporate an
`anti-bacterial agent or agents into the silicone liner which
`substantially suppresses the over-growth of bacteria between
`the liner and the residuum.
`
`Yet another object of the invention is to provide and
`incorporate a umbrella made of flexible material, such as
`silicone, at the distal end of the liner for attaching a rod
`which is used as part of a prosthesis to enable the amputee
`to walk thereon.
`
`In an embodiment of the present invention, the thickened
`upper portion of the wall of the silicone liner may be
`comprised of a plurality of bands molded into the upper
`portion thereof. At
`least
`two of these bands may be
`employed so that the liner can be trimmed between the bands
`if the liner is uncomfortable to the person wearing it because
`the upper portion of the liner may ride too high on the thigh.
`Preferably, the bands may be spaced % inch apart. The
`second band also strengthens the liner wall which increases
`durability of the liner and thus its useful life. The second
`band also improves the seal of the liner while reducing the
`shear strain on the skin of the wearer.
`
`The anatomical shape and distal taper approximates the
`naturally occurring shape of the amputation limb. This
`anatomical correctness greatly enhances overall comfort and
`offers far more uniform and appropriate compression to the
`soft underlying tissues. The anatomical shape and distal
`
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`
`4
`taper of the silicone liner offers the wearer a pre-fabricated
`fit on a par with those utilizing an expensive, custom made
`silicone liner. The availability of many circumferential sizes
`and shapes will accommodate the vast majority of amputa-
`tion shapes. The anatomical shape and distal taper of the
`silicone liner reduces the potential for uneven stretching,
`thus prolonging the useful life of the liner and enhancing the
`comfort of the wearer.
`
`A further embodiment of this invention incorporates an
`anti-bacterial agent or several anti-bacterial agents in
`combination,
`into the silicone material
`to inhibit over-
`population of naturally occurring skin bacteria. It is thought,
`in light of the large population of bacteria present on the
`skin, that these normally occurring skin bacteria are gener-
`ally harmless microorganisms that are physiologically ben-
`eficial. These normally occurring skin bacteria are found in
`hair
`follicles and in moist
`intertriginous locations.
`Conditions, which encourage the skin to be constantly moist
`from sweating, occluded (by a relatively impermeable
`material, such as a silicone liner) and immersed, will make
`it extremely susceptible to invasion by pathogenic microor-
`ganisms. Two of the aforementioned conditions, which
`increase the skin’s vulnerability to bacteriological infection,
`are always present when an amputee utilizes a prosthetic
`silicone liner, that is, constant moisture and occlusion.
`Skin dryness of the residuum (stump) and good hygiene
`(frequent cleansing with a mild detergent) are the principal
`mechanisms for prevention of bacteriological over-
`population. Although variable (significant to minimal), there
`is always some level of moisture present, from perspiration,
`on the residuum when a prosthetic silicone liner is worn.
`Good hygiene via frequent washing of the residuum during
`the day is difficult and inconvenient for the amputee. Since
`the environment within the prosthetic silicone liner is so
`conducive to the marked proliferation of bacteria and the
`increased probability of infection (folliculitis), the incorpo-
`ration of a low-level, time-released, anti-bacterial agent or
`agents into the silicone material, suppresses such an over-
`population of bacteria and the potential for infection of the
`residuum. Folliculitis, furuncles, carbuncles and other bac-
`teriological infections are commonplace for an amputee,
`particularly a lower-limb amputee.
`Anti-bacterial agents, such as “NEOSPORIN,” “BACI-
`TRACIN” and “SILVEDENE” are prepared by pharmaceu-
`tical chemists under appropriate and industry standard con-
`ditions. Newer, and possibly more beneficial, anti-bacterial
`agents may also be utilized in this manner as they become
`available. A solution of the anti-bacterial agent or agents in
`combination are mixed into either the Part A, Part B or both
`of the containers of the two-part silicone material prior to
`injection of the silicone into the prosthetic mold, which
`when cured, forms the prosthetic silicone liner. The concen-
`trations of the anti-microbial agent(s) are substantially lower
`than the concentration one would receive from a topical
`application of the same or similar agent. For instance, if a
`topical anti-bacterial cream contains a 5% concentration of
`erythromycin or dicloxacillin, then the prosthetic silicone
`liner will only permit levels of such agents reaching the skin
`to achieve that of a portion of 1% and up to 2% of that
`agent’s concentration. Of importance, is that the intent of
`this embodiment is to control or reduce the over-population
`of naturally occurring bacteria via a controlled low-level,
`time-released anti-bacterial agent(s) within a prosthetic sili-
`cone liner which is highly conducive to bacteriological
`over-population and subsequent bacteriological infection. It
`is not the intent of this embodiment to treat or cure bacte-
`
`riological infections.
`
`Otto Bock
`
`Exhibit 2002
`
`Page6
`
`Otto Bock Exhibit 2002 Page 6
`
`

`

`5,888,216
`
`5
`
`The curing of silicones (polymers) results in the formation
`of three dimension chemical structures to which anti-
`
`bacterial agents may join. The chemical composition of the
`polymer may be altered to effect precise control of the
`release of the anti-bacterial agents. As prosthetic silicone
`liners typically have a useful life of only six months to one
`year, it is envisioned that the anti-bacterial agent(s), con-
`tained within its silicone structure, offer a similar time of
`release. The moisture from perspiration always present on
`the residuum (within the prosthetic silicone liner) actually
`serves as the vehicle to move the anti-bacterial agent(s) from
`the silicone material to the skin in order to control bacte-
`
`riological over-population. Without moisture (a solution) the
`anti-bacterial agent(s) would never reach the skin of the
`residuum. The movement of the anti-bacterial agent(s) from
`the prosthetic silicone liner to the residuum occurs as a
`consequence of entropy, that is, the anti-bacterial agent(s)
`will move from areas of greater concentration (within the
`silicone) to areas of lesser concentration (the skin).
`A metal umbrella, typically made of aluminum, may be
`installed in the thickened distal end of the silicone liner for
`
`attachment of a walking piece to the liner and residuum
`socket. A preferred embodiment, however, of the present
`invention uses a flexible umbrella that is installed in the
`thickened distal end of the silicone liner. This flexible
`umbrella is made of a flexible material such as silicone, and
`is an improvement over the aluminum and polycarbonate
`umbrellas. The flexible umbrella of the present invention
`does not fracture as does the polycarbonate types and it
`bends and flexes, unlike the metal umbrella, with the soft,
`distortable silicone liner material which further enhances
`distal limb comfort.
`
`Other and further objects, features and advantages will be
`apparent from the following description of presently pre-
`ferred embodiments of the invention, given for the purpose
`of disclosure and taken in conjunction with the accompa-
`nying drawings.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`FIG. 1 is a elevational view of a core for fabricating a
`prosthesis made in accordance with the present invention;
`FIG. 2 is an elevational view illustrating different lengths
`of the core made in accordance with this invention;
`FIG. 3 is cross sectional view taken alone line 3, 3 of FIG.
`
`1;
`
`1 FIG. 4 is cross sectional view taken alone line 4, 4 of FIG.
`, FIG. 5 is cross sectional view taken alone line 5, 5 of FIG.
`1’ FIG. 6 is a elevational view of a prosthesis made in
`accordance with this invention showing the use of an
`umbrella fixture;
`FIG. 7 is an enlarged frontal view of the face of the
`umbrella fixture illustrated in FIG. 6; and
`FIG. 8 is a cutaway elevational view of another prosthesis
`embodiment of this invention.
`
`DESCRIPTION OF THE PREFERRED
`EMBODIMENTS
`
`Referring now to the drawings, the details of the preferred
`embodiments of the present
`invention are schematically
`illustrated. Like elements in the drawings will be repre-
`sented by like numbers, and similar elements will be rep-
`resented by like numbers with a different lower case letter
`suffix. Referring now to FIG. 1, a core is generally indicated
`
`6
`by the numeral 10. The core is preferably formed of alumi-
`num in two or three sections. The three section core com-
`prises a lower third module 20, a knee module 22 and an
`upper third module 24. The two section core combines the
`knee module 22 and upper third module 24 into one
`machined unit module. The two section core eliminates one
`joint seam which would normally appear on the inside of the
`silicone liner fabricated therefrom. A center line 21 repre-
`sents the mid point of each of the modules 20, 22 and 24. An
`alignment ring 26 is provided at the top of the upper third
`module 24. Alocking key 28 is affixed at the top of the upper
`third module 24. The lower third module 20 extends from
`the knee module 22 at an angle (X, where the angle (X may be
`selected from 20 to 60 degrees. As illustrated in FIG. 2, the
`length of the lower third module 20 can have various lengths
`32, 33, 34 or 35 depending on the condition of the limb on
`which the prosthesis is to be used. Cross sections of the
`aluminum core 10 are illustrated in FIGS. 3, 4 and 5.
`Referring now to FIG. 6, a prosthesis liner according to
`the present invention is generally indicated by the numeral
`50 and is preferably made of silicone polymer formed over
`the metal core 10 (illustrated in FIG. 1) by placing and
`securing the metal core 10 into a female mold (not
`illustrated). The liner 50 has the same general shape as the
`aluminum core 10 and has the same flexed angle (X which
`may be from 20 to 60 degrees. The liner 50 has a thickened
`band 56 around its top or upper part 54. The thickened band
`56 has a rounded radius 58 on its top edge. The lower end
`55 of the liner 50 has an anatomical taper 53 so the cross
`section of the liner 50 decreases from its approximate
`midpoint 51 to its lower end 55. The taper 53 angle,
`indicated by the numeral 52, may be from 5 to 12 degrees.
`An attaching means generally indicated by the numeral 62 is
`provided at the lower end 55 of the liner 50 to allow a lower
`leg with foot portion or walking piece (not illustrated) to be
`affixed to a threaded coupling 66.
`Referring now to FIG. 7, a frontal view of the face of
`attaching means 62 is illustrated in more detail. The attach-
`ing means 62 may take the form of an umbrella 67 shaped
`fitting or shuttle housing which conforms with the closed
`curvature 64 (FIG. 6) at the lower (distal) end 55 of the liner
`50. The threaded coupling 66 of the umbrella 67 is adapted
`for attachment of a desired walking piece (not illustrated).
`The umbrella 67 is generally circular in shape with a series
`of oval openings 68, evenly spaced and extending around the
`circular shape of the umbrella 67. The umbrella 67 may be
`made from a metal such as aluminum, or preferably from a
`flexible material such as silicone.
`
`Referring to FIG. 8, a cutaway view of another embodi-
`ment of the present invention is illustrated. A liner 50a has
`at least two thickened bands 56a and 56b around its top or
`upper part 54a. The bands 56a and 56b are preferably spaced
`apart % inch. The bands 56a and 56b enhance the seal
`between the liner and residuum and improve the durability
`of the liner and thus increase its useful life. In addition, the
`liner 50a may be trimmed between the bands 56a and 56b
`(removing the % inch portion above band 56b of the upper
`portion 54a of the liner 50a, and the band 56a) to reduce the
`length of the liner over the thigh when there is discomfort to
`the wearer from the normal length of the upper part 54a.
`In producing a prosthetic below-knee silicone liner in
`accordance with the present invention, a unique methodol-
`ogy has been employed. An initial core model, representing
`the actual shape and circumference of a particular size
`amputation limb, is initially sculpted in plaster of paris. The
`shape of this initial core model
`is representative of an
`amputation limb of which an initial plaster wrap impression
`is obtained from the actual amputation limb.
`
`10
`
`15
`
`20
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`25
`
`30
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`35
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`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`Otto Bock
`
`Exhibit 2002
`
`Page?
`
`Otto Bock Exhibit 2002 Page 7
`
`

`

`5,888,216
`
`7
`This amputation limb model is obtained in a selective
`manner. The limb model must be relatively uniform in shape
`and have present substantially no anatomical anomalies.
`Once obtained, a negative wrap cast is filled with a dental
`stone type plaster of paris. The negative wrap cast
`is
`removed, leaving only the positive plaster of paris model of
`the amputation limb. The model
`is reduced,
`in varying
`amounts, in all regions of the plaster model. The model is
`smoothed, blended and checked to confirm that a desired
`angle selected from a range of approximately 20 to 60
`degrees, as measured from the intersection of two lines
`formed by an extended line from the front of the thigh to the
`long axis of the front of the remaining tibia. Further sculpt-
`ing ensures that the distal
`third of the plaster model is
`tapered and rounded (FIG. 3), that the middle knee area is
`oval shaped (FIG. 5), and that the upper third of the plaster
`model
`is in a substantially rounded configuration. The
`plaster model also may be made in a neuter form, that is,
`neither left-sided nor right-sided. This is achieved artisti-
`cally and is generally accurate, but may not be completely
`anatomically correct.
`The plaster model is then measured and a computer added
`design (“CAD”) representation of the model is produced.
`The left and right sides of the model are further detailed to
`produce a mirror image. All other features and goals for the
`shape of the model are performed via CAD techniques. The
`CAD model blueprint and mathematical relationships are
`transferred to a CNC machine. The core model is then cut
`
`from a large block of solid aluminum. A locking key 28 (see
`FIG. 1) is produced as part of the upper third of the model.
`When complete the solid core model is cut into three distinct
`sections (the lower third module 20, the knee module 22 and
`the upper third module 24). Each of the modules 20, 22, 24
`is further machined internally. Holes are provided for later
`insertion of a heater core (not illustrated). Additional holes
`are made and tapped in order to bolt the individual modules
`20, 22, 24 together.
`This feature (sectional core modules) is necessary due to
`the pre-flexion angle (X which may be selected from 20 to 60
`degrees. As there now exists a clear delineation of the thigh
`and lower leg sections of the model, limb length becomes a
`consideration never before required by the prior art straight
`molds. The removable distal third section (module 20) of the
`core model will be interchanged with other distal
`third
`sections of various lengths. This is important as there exists
`a great variety of amputation limb lengths requiring that
`each of the various circumferentially sized core models offer
`this feature. All distal third core sections preferably are made
`in lengths of 4, 6, 8 and 10 inches, however, any length from
`2 to 12 inches is feasible and contemplated herein. Each of
`the various length third core sections (module 20) are
`machined so as to properly fit the lower margin of the knee
`module 22 with a minimum of a seam.
`
`10
`
`15
`
`20
`
`25
`
`30
`
`35
`
`40
`
`45
`
`50
`
`Models having different cores of varying circumferences
`also may be manufactured in the aforementioned manner,
`each with additional distal
`third sections of the various
`
`55
`
`lengths described. The model circumferences, as measured
`from 6 cm from the very distal end, may range in size, for
`example, from 10 cm to 30 cm, in increments of 2 cm.
`The finished core models and the various additional
`
`length modules are polished and plated. Large blocks of
`aluminum are mathematically machined to create cavities
`inside the aluminum blocks (not illustrated) that precisely fit
`the core model and the upper key previously mentioned. The
`inner, negative cavity is then dimensionally increased by
`additional machining to create a 1.5 to 2 mm gap between
`the core model and the inner aspect of the aluminum block.
`
`60
`
`65
`
`8
`There are instances when below-knee amputees would
`desire and request a prosthetic silicone liner with the fea-
`tures of the current invention but with an alteration. Ampu-
`tee athletes, some geriatric and other amputees of various
`ages might seek a thicker, softer and squashier prosthetic
`silicone liner. The alteration would require fabrication of a
`new core mold that is circumferentially smaller than the
`present one, which now creates a prosthetic silicone liner
`that is 1.5—2 mm thick. The new and smaller core mold
`
`would be created by a CNC lathes and other equipment.
`Machining would follow an identical tool path to the origi-
`nal core, only smaller, so that it creates a larger gap between
`the new core and the existing, unmodified female molds.
`This larger gap of 5—9 mm would create a prosthetic silicone
`liner having a 5—9 mm wall thickness. The present invention
`additionally contemplates a liner wall thickness of 5—9 mm.
`This gap will later be filled with an injected liquid silicone
`material and cured to form the silicone liner according to the
`present invention. The inner, negative cavity of the alumi-
`num block is polished and plated. Holes are drilled,
`strategically, in order to achieve proper silicone filling of the
`overall mold when it is clamped together over the inner core
`model. Vents (additional holes) are also added to facilitate
`the silicone filling process. Additional lengthening sections
`of the female mold must also be fabricated to accommodate
`
`the various lengths of the inner core model. The lowest
`section of the female mold is adapted to accept the umbrella
`67 (FIGS. 6 and 7). The lowest section can also be capped
`when the umbrella 67 option is not required by an amputee
`user.
`
`A custom-designed clamping station is constructed to
`hold and exert high pressures upon the metal mold. Prior art
`molds typically are injected with liquid silicone when in a
`vertical orientation. The present invention, with its anatomi-
`cal shape and fiexion angle selected from 20 to 60 degrees,
`preferably is injected in a horizontal orientation to ensure
`proper filling of the mold cavity with liquid silicone.
`The injection molding procedure involves moving a two
`part, high-strength, highly flexible (when cured), heat-cured
`liquid silicone into the female mold from an outside port
`which fills the gap around the inner core model. A heater
`core is placed into the core model and it is heated to properly
`and rapidly cure the silicone material. Pressure is exerted
`onto the female mold by a custom-made clamping station
`which may be in excess of 30 tons simultaneously with the
`injection process. This method of fabricating a liner accord-
`ing to the present invention will produce a high-strength,
`optically-clear, thin-walled silicone liner. The liquid silicone
`material cures typically in 10—15 minutes. The heater core is
`then turned off, the clamping station is opened, the female
`mold is separated and the silicone liner is unrolled off the
`inner core model.
`
`invention is an
`Another novel feature of the present
`anti-bacterial agent mixed in with the liner material. This
`anti-bacterial agent in the liner substantially suppresses the
`growth of bacteria between the liner and the residuum.
`During fabrication, as disclosed above. of the liner an
`anti-bacterial agent or combination of anti-bacterial agents
`such as “NEOSPORIN,” “BACITRACIN” or
`“SILVEDENE” is added to the liner material. When the liner
`
`is placed over the residuum, the anti-bacterial agen