A novel way of locking and unlocking an adjustment device for an artificial leg or arm makes it possible to perform an adjustment of the prosthesis, without necessitating disassembly of the prosthesis or the removal of the prosthesis from the patient. This facilitates the work in adjusting the translatory position and the angular position, and the adjustment device also offers a further degree of freedom by the addition of the possibility of distal adjustment. The novel combination provides a locking ring (40) on the adjustment head. The locking ring offers a stable, adjustable locking of the adjustment head against a coupling sleeve (50) on the stump, while at the same time fixing the translatory position of the prosthesis. The prosthesis is then provided with a stable, adjustable setting of the distal length of the prosthesis by means of the locking ring (40), which greatly facilitates fine adjustment of the length of the prosthesis, since there is no need to disassemble the prosthesis for performing such a distal length adjustment. The angular adjustment is carried out by means of a pyramid adapter pin (23) which is arranged either in the upper, or in the lower part of the adjustment head. Inclined adjustment screws corresponding to the inclined sides of the pyramid adapter pin are arranged in the corresponding upper or lower part of the adjustment head. The arrangement allows a simple way of disassembling the adjustment head in two parts.

A connecting part of a ball joint between leg prosthesis components with a lange intended to fasten to the one component, the flange having an adjusting element position on it, consisting of a cup and a four-sided pyramid positioned centrally upon its point. To improve the adjustability of the connecting part, the flange is a rectangular flange with four holes, upon which the adjusting element is eccentrically positioned.

The present invention relates to a four hole offset alignment device that is adjustable in the lateral or medial direction and the anterior or posterior direction at a single interface between the two pieces of the present invention. A first piece is provided having a body with a central axis. A positioner is on the first side of the body. A dome with a pyramid is on the second side of the body. A second piece is provided having a central axis and a flange. Four walls upstand from the flange to define an opening. The positioner can be selectably received within the opening while the central axis of the first piece remains parallel to the central axis of the second piece. The pieces are lockable in place with respect to each other at the selected offset alignment.

An adjustment head is provided to attach an elongated member of an artificial leg to a prosthetic leg. The adjustment head includes an upper portion and a lower portion. The upper portion provides adjustment of the elongated member in a translatory direction. The lower portion, in combination with the upper portion, provides adjustment of the elongated member in an angular direction. In making the translatory adjustment, the screw provided for this purpose will not be subject to direct breaking forces by being angled due to any angular adjustment of the elongated member, such screw always being maintained in a fixed vertical alignment.

An adjustable adapter (13) for lower leg prostheses including an adapter housing (14) attachable to the lower leg prosthesis (2), a spheroidal adapter head (8) rotatable inside the housing (14) and a prosthesis collar attachment member (4) that can be shifted sideways relative to the adapter head (8), which member (4) can be fastened to a prosthesis collar (5) whereby the spheroidal part (12) of the adapter head (8) is on the exterior of the essentially tube shaped adapter head (8) having an internally tube shaped part in which there are parts (26, 27, 28) arranged to allow the prosthesis collar attachment member (4) to be shifted sideways.