Prosthetic foot with tunable performance

• US 7,708,784 B2
• Filed: 03/28/2008
• Issued: 05/04/2010
• 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:
  US12/057,607
• Publication Number:
  US 20080183302A1
• Time in Patent Office: 767 Days
• Field of Search: 623 47- 55, 623/27, 623/56
• 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 lower extremity prosthesis comprising:

a longitudinally extending foot keel, said foot keel comprising a longitudinally extending, semi-rigid, resilient member having a forefoot portion at one end, a hindfoot portion at an opposite end and a relatively long midfoot portion extending between said forefoot and hindfoot portions;

a resilient, monolithically formed, S-shaped shank having a lower end connected to the foot keel and extending upwardly from the foot keel by way of an anterior facing convexly curved portion of the shank forming an ankle joint area of the prosthesis, the shank extending upwardly in a substantially reversely curved manner above the ankle joint area to an anterior facing concavely curved portion of the shank above the ankle joint area to connect with a lower extremity prosthetic socket on a person'"'"'s leg stump, the width of the shank in the frontal plane of the prosthesis being greater than the thickness of the shank in the sagittal plane along the length of the shank such that the upper end is moveable longitudinally of the foot keel in response to force loading and unloading of the shank during use of the prosthesis; and

a fastening arrangement connecting and securely positioning the lower end of the shank to the foot keel.

2. The lower extremity prosthesis according to claim 1, wherein the thickness of the foot keel tapers from the midfoot portion toward the forefoot portion.

3. The lower extremity prosthesis according to claim 1, wherein the foot keel forefoot portion is formed with plural expansion struts which create improved biplanar motion capability of the forefoot portion, adjacent expansion struts being separated by an expansion joint extending forward from the midfoot portion of the foot keel to the anterior edge of the forefoot portion.

4. A lower extremity prosthesis according to claim 3, wherein the plural expansion struts include medial, and lateral expansion struts.

5. The lower extremity prosthesis according to claim 1, wherein the fastening arrangement includes a coupling element and at least one fastener.

6. The lower extremity prosthesis according to claim 1, wherein the midfoot portion of the foot keel is upward convexly curved.

7. The lower extremity prosthesis according to claim 6, wherein the midfoot portion is upward convexly curved over the entire longitudinal extent of the midfoot portion between the forefoot portion and a hindfoot portion of the foot keel.

8. The lower extremity prosthesis according to claim 1, wherein the anterior end of the forefoot portion of the foot keel is upward concavely curved.

9. The lower extremity prosthesis according to claim 1, wherein the foot keel has an anterior plantar surface weight bearing area which has a longitudinal axis which is parallel to the frontal plane of the foot keel.

10. The lower extremity prosthesis according to claim 1, wherein the foot keel includes posterior and anterior plantar surface weight bearing areas and a non-weight bearing midportion extending between the weight bearing areas;

and wherein the anterior plantar surface weight bearing area of the member has laterally spaced expansion struts which create biplanar motion capability of the foot keel.

11. The lower extremity prosthesis according to claim 10, wherein the fastening arrangement attaches the lower end of the calf shank to the foot keel with the anterior facing convexly curved lower portion of the calf shank adjacent the non-weight bearing midportion of the foot keel.

12. The lower extremity prosthesis according to claim 1, wherein the foot keel includes a pad on a posterior plantar surface weight bearing area thereof.

13. The lower extremity prosthesis according to claim 1, further comprising an adapter connected to a proximal portion of the shank for use in connecting the prosthesis to a supporting structure on a person'"'"'s residual leg.

14. The lower extremity prosthesis according to claim 1, wherein the shank has a straight upper end.

15. The lower extremity prosthesis according to claim 1, wherein the foot keel is formed of a single piece of resilient material.