Socket system including a vacuum liner for prosthetic or orthotic devices and associated methods
The socket system includes a socket and a vacuum liner. A one-way valve is positioned within the closed distal end of the socket and provides controlled fluid communication between the interior socket space and an external environment. The closed distal end of the vacuum liner includes a distal portion formed of a higher durometer elastomeric material than the surrounding portions of the liner, and including a concave section extending from an external surface thereof towards the interior liner space. The socket, on the interior of the closed distal end thereof, includes a receiving portion that corresponds to and receives the distal portion of the vacuum liner (e.g. matching the perimeter and depth of the distal portion). The receiving portion includes a bottom surface (e.g. a flat surface) opposite to the concave section of the vacuum liner when received therein, and defining an exterior liner space therewith.
1. A vacuum liner for use with a prosthetic device for an amputee, the prosthetic device including a socket having a valve, the vacuum liner arranged to be secured to a residual limb, the vacuum liner comprising:
an elongated tube defining a central axis, and having a closed distal end and an open proximal end located along the central axis, and the elongated tube defining an interior liner space configured to receive the residual limb;
a distal portion forming a protrusion located at a bottom of the distal end of the elongated tube and defining an exterior liner space including a recessed surface located a depth into the protrusion and extending towards the distal end of the elongated tube, the protrusion being coaxial with the central axis;
wherein the distal portion is sized and configured for mating against the socket so that when an amputee walks, the exterior liner space collapses under weight of the amputee and forces air contained therein out of the socket through the valve, and as weight is relieved from the prosthetic device during a swing phase of walking, the protrusion is urged to return to a predetermined, non-collapsed shape, pulling air into the exterior liner space from the socket.
2. The vacuum liner of claim 1 , wherein the protrusion is disk-shaped.
3. The vacuum liner of claim 1 , wherein the distal portion is formed of a higher durometer material than surrounding portions of the elongated tube.
4. The vacuum liner of claim 3 , wherein a durometer hardness of the elongated tube is between 38-55 on the Shore-OO scale, while a durometer hardness of the distal portion is between 60-90 on the Shore-OO scale.
5. The vacuum liner of claim 1 , wherein the recessed surface is concave and is integrally formed with the elongated tube as a monolithic unit.
6. The vacuum liner of claim 1 , wherein the distal end integrally forms the distal portion.
7. The vacuum liner of claim 1 , wherein a bottom periphery of the distal portion is flat.
8. The vacuum liner of claim 1 , wherein the distal end of the liner has a thickness that is thicker than a thickness at the open proximal end.
9. The vacuum liner of claim 1 , wherein the liner is formed from an elastomeric material.