Prosthetic foot with tunable performance

• US 7,364,593 B2
• Filed: 04/08/2003
• Issued: 04/29/2008
• Est. Priority Date: 03/30/2001
• Status: Expired due to Fees

• Current Assignee: BioQuest Prosthetics LLC
• Original Assignee: BioQuest Prosthetics LLC
• Inventors: Townsend, Barry W., Claudino, Byron K.
• Primary Examiner(s): Willse; David H.
• Assistant Examiner(s): Blanco; Javier G.
• Application Number:
  US10/408,107
• Publication Number:
  US 20030191540A1
• Time in Patent Office: 1,848 Days
• Field of Search: 623/27, 623/38, 623 47- 53, 623/54, 623/55
• US Class Current: 623/52
• CPC Class Codes: A61F 2/60 Artificial legs or feet or parts thereof
• CPC Class Codes: A61F 2/66 Feet; Ankle joints
• CPC Class Codes: A61F 2/6607 Ankle joints
• CPC Class Codes: A61F 2/74 fluid , i.e. hydraulic or pneumatic
• CPC Class Codes: A61F 2/76 Means for assembling, fitting or testing prostheses, e.g. for measuring or balancing, e.g. alignment means
• CPC Class Codes: A61F 2002/30433 using additional screws, bolts, dowels, rivets or washers e.g. connecting screws
• CPC Class Codes: A61F 2002/30462 retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: A61F 2002/5001 Cosmetic coverings
• CPC Class Codes: A61F 2002/5003 having damping means, e.g. shock absorbers for implantable joints A61F2002/30563
• CPC Class Codes: A61F 2002/5006 Dampers, e.g. hydraulic damper
• CPC Class Codes: A61F 2002/5007 having elastic means different from springs, e.g. including an elastomeric insert elastic coating A61F2002/3007; springs A61F2002/5072; plate-like springs for feet A61F2002/6657
• CPC Class Codes: A61F 2002/5009 having two or more elastomeric blocks
• CPC Class Codes: A61F 2002/503 for adjusting elasticity, flexibility, spring rate or mechanical tension
• CPC Class Codes: A61F 2002/5032 for adjusting fluid pressure
• CPC Class Codes: A61F 2002/5033 for adjusting damping damping means A61F2002/5003
• CPC Class Codes: A61F 2002/5075 Multiple spring systems including two or more helical springs
• CPC Class Codes: A61F 2002/5079 Leaf springs A61F2002/6657 takes precedence
• CPC Class Codes: A61F 2002/5083 modular
• CPC Class Codes: A61F 2002/607 Lower legs
• CPC Class Codes: A61F 2002/6614 Feet
• CPC Class Codes: A61F 2002/6621 : Toes
• CPC Class Codes: A61F 2002/6628 : Big toes
• CPC Class Codes: A61F 2002/6635 : Metatarsals
• CPC Class Codes: A61F 2002/6642 : Heels
• CPC Class Codes: A61F 2002/665 : Soles
• CPC Class Codes: A61F 2002/6657 : having a plate-like or strip-like spring element, e.g. an energy-storing cantilever spring keel
• CPC Class Codes: A61F 2002/6664 : Dual structures made of two connected cantilevered leaf springs
• CPC Class Codes: A61F 2002/6671 : C-shaped
• CPC Class Codes: A61F 2002/6678 : L-shaped
• CPC Class Codes: A61F 2002/6685 : S-shaped
• CPC Class Codes: A61F 2002/704 : computer-controlled, e.g. robotic control
• CPC Class Codes: A61F 2002/7615 : Measuring means for implanting artificial joints A61F2/4657
• CPC Class Codes: A61F 2220/0041 : using additional screws, bolts, dowels or rivets, e.g. connecting screws
• CPC Class Codes: A61F 2220/0075 : sutured, ligatured or stitched, retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: A61K 9/4816 : Wall or shell material

Abstract

A prosthetic foot incorporate a foot keel and a calf shank connected to the foot keel to form an ankle joint area of the prosthetic foot. The foot keel has forefoot and hindfoot portions and a relatively long midfoot portion extending between and upwardly arched from the forefoot and midfoot portions. The calf shank includes a downward convexly curved lower end which is attached at a portion thereof to the keel midfoot portion by way of an adjustable fastener arrangement. The foot has biplanar motion capability and, in a preferred form, also has high low dynamic response characteristics. The adjustable fastener arrangement permits adjustment of the alignment of the calf shank and the foot keel with respect to one another in the longitudinal direction of the foot keel for tuning the performance of the prosthetic foot.

Claims

1. A calf shank for a prosthetic foot having a longitudinally extending foot keel, comprising:

a monolithically formed elongated, semi-rigid, resilient member with a length which provides a lower portion for attachment to the foot keel defining an ankle joint area of the prosthetic foot, a middle portion extending substantially upward above human ankle joint height and the ankle joint area in a substantially curvilinear manner defining a lower prosthetic part of a leg, and a proximal portion for connection to a supporting structure on a person'"'"'s residual leg, said lower portion being sagitally oriented and posteriorly terminating in a free end, and said lower portion curving upward anteriorly to said middle portion with increasing radius of curvature and being anterior facing continuous convexly curved, said ankle joint area and lower prosthetic part of a leg defined by the resilient member providing means for sagital, anterior dorsiflexion and posterior plantarfiexion motion capabilities in response to a ground reaction force created in a person'"'"'s gait in the prosthetic foot; and

fastening arrangement means for attaching and securely positioning the lower portion of the member to the foot keel to transfer a person'"'"'s body weight through the resilient member throughout the stance phase of gait to oppose the ground reaction force of the prosthetic foot, the fastening arrangement means including means for selectively adjusting the position in the longitudinal direction of the foot keel that the lower portion of the resilient member is secured to the foot keel before an activity for tuning the performance of the prosthetic foot, wherein said fastening arrangement means includes a fastener for attaching and securely positioning the lower portion of the member to the foot keel, and wherein said means for selectively adjusting the position includes an opening through which said fastener extends through the member, the opening being elongated in the longitudinal direction of the foot keel along which said fastener can be slid.

2. The calf shank according to claim 1, wherein said lower portion and said anterior facing continuous convexly curved surface are in the shape of a parabola.

3. The calf shank according to claim 1, wherein said calf shank is S-shaped.

4. The calf shank according to claim 1, wherein said calf shank is J-shaped.

5. The calf shank according to claim 1, wherein each of said proximal and lower portions of said resilient member are convexly rounded to respective free ends of said member in the same direction, said middle portion joining said rounded ends on a side of said member opposite that of said free ends.

6. The calf shank according to claim 1, wherein the fastening arrangement means further includes a coupling element.

7. The calf shank according to claim 1,

wherein the width of the elongated, resilient member in the frontal plane in the prosthetic foot is greater than the thickness of the member in the sagittal plane throughout the entire length of the member such that the member, in response to a ground reaction force created in the prosthetic foot in gait, flexes substantially in the longitudinal direction of the foot keel for storing, releasing and directing energy in a longitudinal direction to improve dynamic response of the prosthetic foot.

8. The calf shank according to claim 1, wherein said lower portion has a downward facing convexly curved surface.

9. The calf shank according to claim 8, wherein said downward facing convexly curved surface and said upward curving anterior facing continuous convexly curved lower portion are in the shape of a parabola.

10. A calf shank for use with a longitudinally extending foot keel in a prosthetic foot, the calf shank comprising:

an elongated, monolithically formed resilient member with a length which provides a lower portion for attachment to the foot keel defining an ankle joint area of the prosthetic foot, a middle portion extending substantially upward above human ankle joint height and the ankle joint area in a substantially curvilinear manner defining a lower prosthetic part of a leg, and a proximal portion for connection to a supporting structure on a person'"'"'s residual leg, said lower portion being sagitally oriented and posteriorly terminating in a free end, said lower portion curving upward anteriorly to said middle portion with increasing radius of curvature and being anterior facing continuous convexly curved, the ankle ioint area and lower prosthetic part of a leg defined by the resilient member providing means for sagital, anterior dorsiflexion and posterior plantarfiexion motion capabilities in response to a ground reaction force in gait in the prosthetic foot;

a fastening arrangement for attaching the lower portion of the member to the foot keel to form an ankle joint area of the prosthetic foot with a person'"'"'s body weight being transferred through the resilient member throughout the stance phase of gait to oppose the ground reaction force on the prosthetic foot;

wherein the fastening arrangement includes a coupling element and first and second releasable fasteners, the coupling element being joined to said lower portion of the member by the first releasable fastener, the second releasable fastener being connected to the coupling element for attaching the coupling element to a foot keel, the first releasable fastener being spaced posteriorly in the coupling element from the second releasable fastener to increase an active length of the calf shank and thereby the dynamic response of the calf shank in gait.

11. The calf shank according to claim 10, further comprising an adapter connected to the proximal portion of the member for connection with a supporting structure on a person'"'"'s residual leg.

12. The calf shank according to claim 10, wherein the member extending upward in a substantially curvilinear manner above the ankle joint area is reversely curved to merge with a straight proximal portion of the member.

13. The calf shank according to claim 10, wherein the member above said lower portion is also anterior facing convexly curved.

14. The calf shank according to claim 13, wherein the lower portion of the resilient member has a downward facing convexly curved resilient surface with a relatively smaller radius of curvature than that of the convexly curved member above the ankle joint area.

15. The calf shank according to claim 10, wherein the member is J-shaped with the lower portion of the J-shape being anterior facing continuous convexly curved and having a downward facing convexly curved resilient surface.

16. The calf shank according to claim 10, wherein the member is in the shape of a parabola.

17. The calf shank according to claim 10, wherein the member is in the shape of a parabola which is reversely curved to merge with a straight proximal portion of the member.

18. The calf shank according to claim 10, wherein the coupling element has a concave surface engaging a convexly curved surface of said lower portion in the vicinity of said first releasable fastener.

19. The calf shank according to claim 18, wherein said coupling element has an additional concave surface in the vicinity of said second releasable fastener for engaging a convex surface of the foot keel to attach the member to the foot keel.

20. The calf shank according to claim 10, wherein the fastening arrangement includes means for the user of the prosthetic foot to adjust the inclination at which the member is attached to the foot keel in the longitudinal direction of the foot keel.

21. The calf shank according to claim 10, wherein the member is S-shaped with a lower portion of the S-shape being anterior facing continuous convexly curved and having downward facing convexly curved resilient surface.

22. The calf shank according to claim 10, wherein each of the proximal portion and lower portion posteriorly terminate in a free end, said middle portion of the member joining the free ends.

23. The calf shank according to claim 10, wherein the member is formed of material having shape-retaining characteristics.

24. A calf shank comprising:

an elongated, monolithically formed resilient member with a lower portion for attachment to the foot keel defining an ankle joint area of the prosthetic foot, a middle portion extending substantially upward above human ankle ioint height and the ankle joint area in a substantially curvilinear manner defining a lower prosthetic part of a leg, and a proximal portion for connection to a supporting structure on a person'"'"'s residual leg, said lower portion being sagitally oriented and posteriorly terminating in a free end, said lower portion curving upward to said middle portion with increasing radius of curvature and being anterior facing continuous convexly curved, said ankle joint area and lower prosthetic part of a leg defined by the resilient member providing means for sagital, anterior dorsiflexion and posterior plantarflexion motion capabilities in response to a ground reaction force created in a person'"'"'s gait in the prosthetic foot;

a fastening arrangement to attach the member to the foot keel, the fastening arrangement including means for adjusting the alignment of the calf shank with respect to the foot keel in the longitudinal direction of the foot keel before an activity for tuning the performance of the prosthetic foot,

wherein the fastening arrangement further includes a coupling element and first and second releasable fasteners, the coupling element being joined to said lower portion of the member by the first releasable fastener, the second releasable fastener being connected to the coupling element for attaching the coupling element to a foot keel, the first releasable fastener being spaced posteriorly in the coupling element from the second releasable fastener to increase an active length of the calf shank and thereby the dynamic response of the calf shank in gait.