Artificial limb with automatic release for free rotation

DETAILED DESCRIPTION Two broad categories of artificial limbs or prostheses are generally known: the exoskeletal type and the endoskeletal type.
An exoskeletal limb is formed with a hard outer shell which is shaped to simulate a real limb and is generally hollow.
In an exoskeletal artificial leg, for example, the shell serves to support the wearer and to house the internal mechanisms of the leg.
An endoskeletal prosthesis includes elongated, internal supporting members, similar to human bones, which are embedded in a foam material and covered by a resilient, flesh-like sheathe or stocking to simulate the appearance of a human limb.
In an endoskeletal artificial leg, the structural members support the wearer, as well as all related mechanisms, and the foam and covering sheath conceal the structural members and mechanisms to lend a realistic appearance to the artificial limb.
The present invention is applicable to endoskeletal limbs.
The figures illustrate an endoskeletal prosthesis in the form an artificial leg 10 embodying the present invention.
The the prosthesis 10 is intended for use by a patient with a leg which has been amputated to a point above the knee.
The prosthesis 10 is constructed so as to be compatable with a modular system of endoskeletal prosthesis components which is available from Otto Bock Orthopedic Industry Inc.
of Minneapolis, Minn.
As is characteristic of endoskeletal devices, the prosthesis 10 has an internal framework 12 simulating the bones forming the skeletal structure of the human leg.
This framework is embedded in a mass of foam material or padding 14 which fills in the shape of the leg and lends a human "softness" to it.
The padding 14 is then surrounded by a sheath of flexible material 16 forming the "outer skin" of the leg.
The framework 12 broadly comprises: a thigh unit 18 incorporating a femoral rotator mechanism described in detail below; a lower leg unit 20 including an artificial foot; and a knee joint unit 22 connecting the units 18 and 20 for relative pivotal movement