EP0331468A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Lower limb prosthesis
Assignee: Chas A Blatchford and Sons Ltd
•
Filing: 1989-03-01
•
Granted: —
•
Expires: 2009-03-01
Abstract
Abstract In a lower limb prosthesis an energy storing foot (10) is combined with a resilient ankle joint (13) which is arranged to allow plantar flexion but substantially to prevent dorsi-flexion. The ankle joint (13) comprises a ball and socket joint (42), the socket (44) of which is extended downwardly on the anterior, medial and lateral sides to form a skirt (44A) positioned so as to compress a resilient ring (54) encircling a ball member (46) of the ball and socket joint (42). Metal plates (56) are embedded in the anterior part of the ring to prevent significant dorsi-flexion. The foot (10) has a single-piece carbon fibre reinforced plastics keel (12) having a lower spring portion (12B) connected at its posterior end as a cantilever to an upper ankle mounting portion (12). The resilience of the foot (10) is adjustable by means of a transversely extending support bar (28) which can be moved longitudinally by rotating an adjusting screw (30). The screw (30) passes through an aperture in the keel (12) and is accessible at the rear of the heel.
Inventors
- 👤 John Jeffrey Shorter
- 👤 Graham James Harris
- 👤 Victor James Woolnough
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 14:07
CPC Classifications
A; A61; A61F; A61F2/00; A61F2/50; A61F2/60; A61F2/66; A61F2/76; A61F2/6607; A61F2/02; A61F2/30; A61F2002/30001; A61F2002/30316; A61F2002/30329; A61F2002/30433; A61F2002/30476; A61F2002/30494; A61F2002/5016; A61F2002/503; A61F2/5044; A61F2002/5055; A61F2002/6614; A61F2002/6657; A61F2002/6671; A61F2220/00; A61F2220/0025; A61F2220/0041
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
83 words
A lower limb prosthesis comprising: an energy storing foot which is resiliently deformable to allow dorsi-flexion of an anterior portion of the foot relative to an ankle mounting portion of the foot; and a resilient ankle joint coupling the ankle mounting portion of the foot to an upper component of the prosthesis and arranged to allow plantar movement of the foot from a rest position relative to the upper component but substantially to prevent dorsi movement of the foot from the rest position.
Claim 2
Dependent Claim
83 words
A lower limb prosthesis comprising: an energy storing foot which is resiliently deformable to allow dorsi-flexion of an anterior portion of the foot relative to an ankle mounting portion of the foot; and a resilient ankle joint coupling the ankle mounting portion of the foot to an upper component of the prosthesis and arranged to allow plantar movement of the foot from a rest position relative to the upper component but substantially to prevent dorsi movement of the foot from the rest position.
Claim 3
Dependent Claim
23 words
A prosthesis according to claim 1, wherein the ankle joint is arranged such that the maximum dorsi-flexion of the ankle joint is 3°.
Claim 4
Dependent Claim
48 words
A prosthesis according to claim 1, wherein the foot and the ankle joint are so arranged that over the majority of the range of combined dorsi-flexion of the foot and the ankle joint, the flexion of the ankle joint represents not more than 30% of the combined dorsi-flexion.
Claim 5
Dependent Claim
144 words
A prosthesis according to claim 1, wherein the upper component defines a shin axis of the prosthesis and wherein the ankle joint and the foot are so constructed that, over the majority of the range of the combined dorsi-flexion of the foot and the ankle joint, the dorsi-flexion of the ankle joint represents not more than 30% of the said combined dorsi-flexion when the upper component is loaded by the combination of a force directed downwardly along the shin axis and a dorsi moment about the ankle joint, the loading being equivalent to the application of a vertically and downwardly directed force on an anterior extension of the upper component such that the force is applied at a distance of 100mm to the anterior of the shin axis and at a height of 150mm above an axis of rotation defined by the ankle joint.
Claim 6
Dependent Claim
164 words
A prosthesis according to claim 1, wherein the upper component defines a shin axis, wherein the foot is so constructed to allow plantar flexion of the foot anterior portion relative to the ankle joint mounting portion, and wherein the foot and ankle joint are so constructed that over the majority of the range of combined plantar flexion of the foot and the ankle joint, the plantar flexion due to the ankle joint represents a least 85% of the said combined plantar flexion when the upper component is loaded by the combination of a force directed downwardly along the shin axis and a plantar moment about the ankle joint, the loading being equivalent to the application of a vertically and downwardly directed force on a posterior extension of the upper component such that the force is applied at a distance of 60mm to the posterior of the shin axis and at a height of 150mm above an axis of rotation defined by the ankle joint.
Claim 7
Dependent Claim
20 words
A prosthesis according to claim 1, wherein the ankle joint is constructed so as to allow medial and lateral flexion.
Claim 8
Dependent Claim
16 words
A prosthesis according to claim 6, wherein the ankle joint comprises a ball and socket joint.
Claim 9
Dependent Claim
92 words
A prosthesis according to claim 7, wherein the ball and socket joint has a ball member comprising a ball portion and a connection shank, and a socket member surrounding the ball portion and having an extension in registry with but spaced radially from the shank, and wherein the ankle joint further comprises a resilient ring encircling the shank and located between the extension and the shank, the arrangement of the extension being such that the ring acts as a resilient buffer resisting at least medial and lateral flexion of the ankle joint.
Claim 10
Dependent Claim
55 words
A prosthesis according to claim 8, wherein the extension is constructed to engage the ring only on the anterior, medial and lateral faces thereof, and wherein the ring has at least one stiffening element embedded in an anterior portion thereof for substantially preventing dorsi-flexion of the ankle joint whilst permitting medial, lateral and plantar flexion.
Claim 11
Dependent Claim
31 words
A prosthesis according to claim 1, wherein the foot is endoskeletal, having a resilient internal keel in the form of a leaf spring extending into the anterior portion of the foot.
Claim 12
Dependent Claim
35 words
A prosthesis according to claim 10, wherein the ankle mounting portion of the foot is part of the keel and is integral with the leaf spring, the keel being formed of a fiber-reinforced plastics material.
Claim 13
Dependent Claim
67 words
A prosthesis according to claim 1, wherein the foot is endoskeletal, having a resilient keel comprising the said ankle-mounting portion of the foot, and elongate lower keel portion extending lengthwise in the foot from a heel portion of the foot into the said anterior portion, and a posterior connecting portion connecting the ankle mounting portion to the lower keel portion in the heel portion of the foot.
Claim 14
Dependent Claim
53 words
A prosthesis according to claim 12, wherein the foot further comprises an adjustable support member coupling the ankle mounting portion of the keel and the lower keel portion thereof ahead of the posterior connecting portion to provide a fulcrum for the lower portion at a position which is variable longitudinally of the foot.
Claim 15
Dependent Claim
32 words
A prosthesis according to claim 13, wherein the keel is a single-piece resilient fiber-reinforced plastics strip U-shaped in side elevation, the ankle mounting portion comprising a plate connectable to the ankle joint.
Claim 16
Dependent Claim
37 words
A prosthesis according to claim 14, wherein the adjustable support member comprises a bar extending transversely of the foot between an upper surface of the keel lower portion and a lower surface of the ankle mounting portion.
Claim 17
Dependent Claim
28 words
A prosthesis according to claim 15, wherein the bar is attached to a longitudinally extending bolt passing through an aperture in the posterior connecting portion of the keel.
Claim 18
Dependent Claim
56 words
A prosthesis according to claim 1, wherein the ankle joint has a lower member detachably connected to the ankle mounting portion of the foot, and wherein the relative position of the said lower member and the ankle mounting portion can be set to any of a plurality of different positions for setting a required heel height.
Claim 19
Dependent Claim
31 words
A lower limb prosthesis comprising the combination of an energy storing foot and a flexible ankle joint, the ankle joint being constructed to allow plantar flexion but substantially to prevent dorsi-flexion.
Claim 20
Dependent Claim
31 words
A lower limb prosthesis comprising the combination of an energy storing foot and a flexible ankle joint, the ankle joint being constructed to allow plantar flexion but substantially to prevent dorsi-flexion.
Claim 21
Dependent Claim
29 words
A prosthesis according to claim 18, wherein the ankle joint is constructed so as to restrict dorsi-flexion of the joint to an angle less than or equal to 5°.
Claim 22
Dependent Claim
38 words
A prosthesis according to claim 18, wherein the rate of resilience of the ankle joint for plantar flexion is greater than ten times that for dorsi-flexion, the resilience being measured as the angular deflection per unit moment applied.
Claim 23
Dependent Claim
103 words
An energy storing artificial foot comprising a keel having an upper load receiving portion, an elongate resiliently deflectable lower portion arranged longitudinally of the foot for transmitting applied loads to the sole of the foot, and a posterior connection connecting the lower portion to the upper portion in a heel portion of the foot, and further comprising a longitudinally adjustable support member coupling the upper portion to the lower portion ahead of the posterior connection to provide a fulcrum for the lower portion at a position which is variable longitudinally of the foot thereby to allow adjustment of the resilience of the foot.
Claim 24
Dependent Claim
103 words
An energy storing artificial foot comprising a keel having an upper load receiving portion, an elongate resiliently deflectable lower portion arranged longitudinally of the foot for transmitting applied loads to the sole of the foot, and a posterior connection connecting the lower portion to the upper portion in a heel portion of the foot, and further comprising a longitudinally adjustable support member coupling the upper portion to the lower portion ahead of the posterior connection to provide a fulcrum for the lower portion at a position which is variable longitudinally of the foot thereby to allow adjustment of the resilience of the foot.
Claim 25
Dependent Claim
42 words
An artificial foot according to claim 21, wherein the keel is a resilient single-piece fibre-reinforced plastics strip U-shaped in side elevation, with the lower portion extending from the heel portion of the foot into the region of the ball of the foot.
Claim 26
Dependent Claim
67 words
An artificial foot according to claim 21, wherein the adjustable support member comprises a bar extending transversely of the foot between an upper surface of the lower keel portion and a lower surface of an upper keel portion, the bar being located by a longitudinal bolt passing through an aperture in the said posterior connection of the keel to be accessible at the rear of the foot.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.