Leg exoprosthesis for adaptation to a thigh stump

• US 6,425,925 B1
• Filed: 10/01/1999
• Issued: 07/30/2002
• Est. Priority Date: 10/01/1998
• Status: Expired due to Fees

• Current Assignee: Schutt & Grundei Orthopadietechnik GmbH
• Original Assignee: Schutt & Grundei Orthopadietechnik GmbH
• Inventors: Grundei, Hans
• Primary Examiner(s): Willse, David H.
• Assistant Examiner(s): STEWART, ALVIN J
• Application Number:
  US09/411,181
• Time in Patent Office: 1,033 Days
• Field of Search: 623/33, 623/39, 623/43, 623/46, 623/27, 623/28, 623/30, 623/31, 623/60, 623/58, 623/32
• US Class Current: 623/32
• CPC Class Codes: A61F 2/2814 Bone stump caps
• CPC Class Codes: A61F 2/30749 Fixation appliances for connecting prostheses to the body
• CPC Class Codes: A61F 2/64 Knee joints
• CPC Class Codes: A61F 2/642 Polycentric joints, without longitudinal rotation
• CPC Class Codes: A61F 2/644 of the single-bar or multi-bar linkage type
• CPC Class Codes: A61F 2/646 of the pin-guiding groove linkage type
• 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 2002/2825 Femur
• CPC Class Codes: A61F 2002/30276 frustopyramidal
• CPC Class Codes: A61F 2002/304 with additional means for limiting said sliding
• CPC Class Codes: A61F 2002/30462 retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: A61F 2002/30507 using a threaded locking member, e.g. a locking screw or a set screw
• CPC Class Codes: A61F 2002/30589 Sealing means
• CPC Class Codes: A61F 2002/30878 with non-sharp protrusions, for instance contacting the bone for anchoring, e.g. keels, pegs, pins, posts, shanks, stems, struts
• CPC Class Codes: A61F 2002/30909 Nets
• CPC Class Codes: A61F 2002/3092 having an open-celled or open-pored structure
• CPC Class Codes: A61F 2002/5038 Hinged joint, e.g. with transverse axle restricting the movement for implantable joints A61F2002/30624
• CPC Class Codes: A61F 2002/5039 allowing only for single rotation
• CPC Class Codes: A61F 2002/5073 Helical springs, e.g. having at least one helical spring
• CPC Class Codes: A61F 2002/5093 Tendon- or ligament-replacing cables implantable A61F2/08
• CPC Class Codes: A61F 2002/607 : Lower legs
• CPC Class Codes: A61F 2002/6872 : attached and mechanically operated by remaining muscle bioelectrical control A61F2/72
• CPC Class Codes: A61F 2002/7887 : for connecting limb exoprostheses to the stump bone
• CPC Class Codes: A61F 2220/0025 : Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2220/0075 : sutured, ligatured or stitched, retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: A61F 2230/0086 : Pyramidal, tetrahedral, or wedge-shaped

Abstract

A leg exoprosthesis for adaptation to a thigh stump (1) has an adapter (2) for a knee joint (3), a knee joint (3) mounted thereon, and a lower leg prosthesis (4) coupled to it. On the lower leg prosthesis (4) a force-transmitting element (5) is coupled into which extending forces are introduced.

Claims

1. A leg exoprosthesis for adaptation to a thigh stump (1), comprising an adapter (2) for a knee joint (3), a knee joint (3) attached thereto, a lower leg prosthesis (4) coupled on the knee joint (3), the adapter (2) having a proximal intramedullary stem element (7) at least partially covered with an open-meshed, three-dimensional spatial network structure (10) which is implantable into a tubular bone stump (8) of the thigh stump (1), the adapter (2) having a distal end provided with a coupling device (9) for connection to the knee joint, and a force-transmitting element (5) coupled to the lower leg prosthesis (4) for transmitting extensor forces to extend the knee joint (3), the force-transmitting element (5) having on its end applied to the thigh stump a connection element (6) in a form of a stirrup configured to be tied to extensor musculature of the thigh.

2. The leg exoprosthesis according to claim 1, wherein the force-transmitting element (5) comprises a bridle band.

3. The leg exoprosthesis according to claim 1, wherein a sealing element (11) is seated at a point where the adapter (2) exits from the thigh stump (1).

4. The leg exoprosthesis according to claim 1, wherein the knee joint (3) comprises an upper part (12) connectable with the adapter (2) and a lower part (13) flexibly connected with the upper part (12) and connectable with the lower leg prosthesis (4), the upper part (12) being supported with skids (14) on sliding surfaces (15) of the lower part (13), the skids (14) being held against the sliding surfaces (15) by spring action, the upper part (12) being swivellable with the skids on the sliding surfaces (15) about a pivot point (16) until reaching an extended position, wherein a vertical main axis of the upper part (12) is shifted anteriorly in relation to a vertical main axis of the lower part (13), the skids (14) in side view having bearing surfaces which, when viewed anterior to posterior, assume constantly diminishing curvature radii about the pivot point and lie on the sliding surfaces (15) which are substantially flat in construction, and wherein the upper part (12) is displaced posteriorally in relation to the lower part (13) with increasing flexion of the joint.

5. The leg exoprosthesis according to claim 4, wherein the lower part (13) of the knee joint (3) has a frame (17) which supports a carrier (18) for the sliding surfaces (15), the upper part (12) is connected by axle journals with braces (20) laterally guided on the frame (17), the braces (20) being rigidly connected by an axle (22) engaging through at least one oblong hole (21) in the frame (17), wherein the axle (22) is biased by a spring (23) relative to the frame (17) and via the braces (20) holds the skids (14) against the sliding surfaces (15) of the lower part (13), and wherein the force-transmitting element (5) is attached to the frame (17) of the lower part (13).