PROSTHESIS SOCKET AND METHOD FOR CONTROLLING AN ADJUSTMENT OF AN INNER CIRCUMFERENCE OF A PROSTHESIS SOCKET

Abstract

A prosthesis socket having a proximal insertion opening and an inner circumference which at least partially surrounds a limb stump, at least one connection device for a prosthesis component, which is connectable to the prosthesis sockets at least one actuator operable to change the inner circumference of the prosthesis socket, and at least one sensor coupled to a control device, wherein the control device is connected to the actuator and activates or deactivates same, depending on the received sensor signals, and to a method for adjusting the inner circumference.

Claims

1-6. (canceled)

7. A prosthesis socket comprising: a proximal insertion opening and an inner circumference which is configured to at least partially surround a limb stump; at least one connection device for a prosthesis component, which is connectable to the prosthesis socket; a volume partially defined by the inner circumference of the proximal insertion opening within the prosthesis socket; and at least one actuator; wherein the actuator is configured to change the inner circumference of the prosthesis socket, changing the volume.

8. The prosthesis socket according to claim 7, wherein the actuator is configured to be driven manually or by a motor.

9. The prosthesis socket according to claim 7, wherein the prosthesis socket is designed in multiple parts with at least two support elements which are configured to receive the limb stump in between the at least two support elements.

10. The prosthesis socket according to claim 9, wherein the at least two support elements are formed or mounted resiliently.

11. The prosthesis socket according to claim 9, wherein the at least two support elements are designed to overlap one another in a circumferential direction.

12. (canceled)

13. The prosthesis socket according to claim 7, further comprising at least one tensioning device arranged on the prosthesis socket and configured to change the inner circumference.

14. The prosthesis socket according to claim 13, wherein the tensioning device is designed as a traction member, a pneumatically or hydraulically driven spreading or tensioning member, a longitudinally slidable spreading or closing element, a movable ring, a tilting element, or a rotatable actuation element.

15. The prosthesis socket according to claim 13, wherein the tensioning device is guided in at least one of eyelets, channels or at least one deflection roller.

16. The prosthesis socket according to claim 13, wherein multiple tensioning devices are arranged independently of one another along a proximal-distal extent of the prosthesis socket.

17. The prosthesis socket according to claim 13, wherein the at least one tensioning device acts in a circumferential direction of the limb stump.

18. The prosthesis socket according to claim 7, wherein, in the closed state, a contact pressure applied to the limb stump by the actuator decreases in a proximal direction.

19. A method for controlling an adjustment of an inner circumference of a prosthesis socket according to claim 7, wherein, when at least one of a predetermined position of the limb stump and a compressive force exerted on the limb stump is detected by at least one sensor, the actuator is activated or deactivated automatically to change the volume.

20. The method according to claim 19, further comprising support elements movable apart from one another by the actuator for opening of the prosthesis socket, a wall socket adapted to be pulled apart or, for the change in circumference, a tensioning device acting against a resilient pretensioning force of the support elements or of the socket wall is relaxed.

21. The method according to claim 19 further comprising support elements or a socket wall of the prosthesis socket are moved towards one another by the actuator or by their resilient behavior from a widened position to a tensioned position with an inner circumference which is reduced in comparison to the starting position.

22. A method for adjusting an inner circumference of a prosthesis socket, comprising: opening the prosthesis socket by moving apart support elements from one another with an actuator or pulling apart a socket wall; changing an inner circumference of the prosthesis socket by relaxing a tensioning device acting against a resilient pretensioning force of the support elements or of the socket wall and changing a volume partially defined by the inner circumference of the prosthesis socket.

23. The prosthesis socket according to claim 7, further comprising at least one sensor coupled to a control device and operable to generate control signals.

24. The prosthesis socket according to claim 7, further comprising a control device connected to the actuator, wherein the control device activates or deactivates the actuator depending on received sensor signals.

25. The prosthesis socket according to claim 7, wherein the actuator is designed as a drive for a pump, a sliding element, a lever, a winding device for traction members, a spreading element, a gear, a device for the activation of a shape memory alloy or of an electroactive polymer, or a switchable magnet.

26. The prosthesis socket according to claim 7, further comprising a switch, a contact switch or a sensor for the detection of an introduced limb stump is arranged in a distal end area of the prosthesis socket.

27. The prosthesis socket according to claim 7, further comprising at least one of an internal pressure sensor and a motor current sensor for the acquisition of the pressure applied by a support element to the limb stump is arranged on a support element.

28. The prosthesis socket according to claim 7, wherein the volume comprises at least one of a bladder, a cushion, and a pocket.

29. The prosthesis socket according to claim 28, wherein the volume is configured to be inflated or deflated to change the volume of the prosthesis socket, a pressure of the volume, and a pressure distribution on the limb stump.

30. The prosthesis socket according to claim 29, wherein if a contact pressure exceeds or decreases below a threshold value, an adjustment of the contact pressure is initiated to change the contact pressure an optimized predetermined pressure.

31. The method according to claim 19, wherein the volume comprises at least one of a bladder, a cushion, and a pocket.

32. The method according to claim 31, further comprising inflating or deflating the volume to change the volume of the prosthesis socket, a pressure of the volume, and a pressure distribution on the limb stump.

33. The method according to claim 32, wherein if a contact pressure exceeds or decreases below a threshold value, an adjustment of the contact pressure is initiated to change the contact pressure an optimized predetermined pressure.

34. The method according to claim 19, wherein, in a closed state, a contact pressure applied to the limb stump by the actuator decreases in a proximal direction.

35. The method according to claim 34, wherein the prosthesis socket further comprises at least one tensioning device arranged on the prosthesis socket and configured to change the inner circumference, wherein the at least one tensioning device comprises at least one of a traction member, a pneumatically or hydraulically driven spreading or tensioning member, a longitudinally slidable spreading or closing element, a movable ring, a tilting element, and a rotatable actuation element.

36. The method according to claim 22, wherein the volume comprises at least one of a bladder, a cushion, and a pocket.

37. The method according to claim 36, further comprising inflating or deflating the volume to change the volume of the prosthesis socket, a pressure of the volume, and a pressure distribution on the limb stump.

38. The method according to claim 37, wherein if a contact pressure exceeds or decreases below a threshold value, an adjustment of the contact pressure is initiated to change the contact pressure an optimized predetermined pressure.

39. The method according to claim 22, wherein, in a closed state, a contact pressure applied to the limb stump by the actuator decreases in a proximal direction.

40. The method according to claim 39, wherein the prosthesis socket further comprises at least one tensioning device arranged on the prosthesis socket and configured to change the inner circumference, wherein the at least one tensioning device comprises at least one of a traction member, a pneumatically or hydraulically driven spreading or tensioning member, a longitudinally slidable spreading or closing element, a movable ring, a tilting element, and a rotatable actuation element.

41. A prosthesis socket comprising: a proximal insertion opening and an inner circumference which is configured to at least partially surround a limb stump; at least one connection device for a prosthesis component, which is connectable to the prosthesis socket; and a volume partially defined by the inner circumference of the proximal insertion opening within the prosthesis socket, wherein a pressure distribution within the volume decreases in a proximal direction.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Below, embodiment examples of the invention are explained in greater detail in reference to the appended figures. In the drawings:

[0046] FIG. 1 shows a top view onto a prosthesis socket and a pressure distribution characteristic line;

[0047] FIG. 2 shows an opened prosthesis socket with a tensioning device and a motor;

[0048] FIG. 3 shows a closed prosthesis socket according to FIG. 2;

[0049] FIG. 4 shows an opened prosthesis socket with multiple tensioning devices and motors;

[0050] FIG. 5 shows a closed prosthesis socket according to FIG. 4;

[0051] FIG. 6 shows a circuit diagram;

[0052] FIG. 7 shows a diagrammatic representation of a device for the opening of a socket;

[0053] FIG. 8 shows a prosthesis socket in a detail view in closed position; and

[0054] FIG. 9 shows the operating principle according to FIG. 8 in opened position.

DETAILED DESCRIPTION

[0055] In FIG. 1, in a top view, a prosthesis socket 1 is represented, which, in the represented embodiment example, is designed as a thigh socket for receiving a thigh stump. In principle, it is also possible to design the prosthesis socket 1 as a lower leg socket or as a prosthesis socket for an upper extremity. On its distal end, the prosthesis socket 1 has an end piece 2 which forms the distal closure of a receiving space for a limb stump. The distal end piece 2 lies opposite a proximal opening 3. The prosthesis socket 1 is formed substantially in the shape of a funnel; it surrounds substantially the entire circumference of the limb stump, which is not represented, and it forms a lower closure, so that a limb stump, optionally together with a liner pulled over the limb stump, is only insertable up to the distal end piece 2.

[0056] On the distal end piece, a connection means 4 for additional prosthesis components is arranged or connected. The closure means 4 are, for example, pyramid adapters, positive-locking receivers, screw receivers, bolts or other devices by means of which additional prosthesis components can be connected to the prosthesis socket 1. In the embodiment example of the prosthesis socket 1 as a thigh socket, a prosthetic knee joint is secured by means of the connection means 4 on the distal end piece 2.

[0057] In the design of the prosthesis socket as a lower leg socket, a prosthetic foot or a lower leg tube is secured as an additional prosthesis component on the connection means 4; in the design as a lower arm socket, a prosthetic hand is secured.

[0058] The end piece 2 can be designed as a flat plate or as a cup-shaped receiver and closure of the prosthesis socket 1. In addition to a preferably dimensionally-stable design of the end piece 2 made of a metal, a plastic or the like, for example, the end piece 2 can also be designed to be flexible. Support elements 5, 6, 7, 8 adjoin the end piece 2 in proximal direction, said support elements being either designed to form a single part with the end piece 2 or produced separately and connected thereto. The support elements 5, 6, 7, 8 are arranged so that they form a receiving space between themselves, in which the limb stump, not represented, can be inserted through the insertion opening 3. The support elements 5, 6, 7, 8 completely surround the limb stump. Due to the design in segments of the support elements 5, 6, 7, 8 and due to either a mobile mounting on the end piece 2 or due to an inherent resilience resulting, for example, from the material selection or a weakening of the material in the area of the end piece 2, it is possible to move the support elements 5, 6, 7, 8 apart from one another or towards one another in order to widen the prosthesis socket or to reduce the insertion opening 3 and the receiving space. The inner circumference of the prosthesis socket 1 is changed by the movement of the support elements due to the activation or deactivation of an actuator.

[0059] According to the represented embodiment example, on the front side of the prosthesis socket 1, three tensioning devices 11, 12, 13 are arranged, by means of which at least the lateral support element 6 can be moved in the direction of the medial support element 5. The orientation of the support element 7 is substantially frontal; an additional support element 8 is secured with a hinge to the end piece 2 and used for improved frontal bracing. The lateral support element 6 can be connected to the additional support element 8.

[0060] In the represented embodiment example, the tensioning devices or tensioning elements 11, 12, 13 are designed as cords, cables or ropes; it is also possible that the represented tensioning devices 11, 12, 13 which are designed in the form of a rope are instead in the form of a belt or else in the form of a rod, a chain, a perforated band or another traction means. It is essential that the tensioning device is suitable for moving the support devices towards one another, that is to say for applying traction forces, wherein, due to the flexible and preferably non-resilient design of the tensioning devices 11, 12, 13, predominantly circular forces are active. Due to the movement of the support elements 5, 6, 7, 8 towards one another, the inner circumference of the prosthesis socket is reduced.

[0061] The tensioning devices 11, 12, 13 are guided in eyelets on the mutually facing margins of the support elements 5, 6 and arranged like shoe laces. In total, three mutually independent tensioning devices 11, 12, 13 are arranged on the prosthesis socket 1, which are arranged with mutual offset with respect to one another in the proximal-distal direction, whereby it is possible that different pressures are exerted on the limb stump at different heights.

[0062] The tensioning devices 11, 12, 13 can be tensioned by means of an actuator, in the embodiment example a motor; for this purpose, the tensioning devices are wound on a roller which is coupled to the motor, for example, by means of a gear, so that relative small motors with high rotation speeds can be used, which results in a saving of installation space and weight. If the motors, which are not represented, are activated, the respective tensioning device 11, 12, 13 is wound, the support devices 5, 6, 7, 8 are moved towards one another, and the prosthesis socket 1 closes around the limb stump.

[0063] Moreover, in the prosthesis socket 1, a control device 40 is arranged, by means of which the actuators or motors (or the actuator or the motor, if only one actuator or motor is used) can be actuated. The control device 40 is connected to the actuators. Moreover, the control device 40 is connected to a switch 45, by means of which the opening or closing of the prosthesis socket 1 can be switched on. In addition to a manual operation and activation of the prosthesis socket by the switch 45 on the proximal end of the frontal support element 7, in the distal area of the receiving space, a contact sensor 30 is arranged, in the embodiment example represented, in the distal end area of the receiving space. If the contact sensor 30 is touched, a signal is transmitted to the control device 40, so that an activation of the actuator/motor or of the actuators/motors occurs automatically, in order to close the tensioning devices 11, 12, 13. The contact sensor 30 can also be designed as a simple switch.

[0064] Along at least one support element 5, pressure sensors 31, 32, 33 are arranged, by means of which the contact pressure of the support elements 5, 6, 7, 8 can be monitored. If preset pressures are reached, the respective actuator is deactivated by means of the control device 40. Advantageously, a pressure distribution is set, as shown in the right diagram in FIG. 1, in which an elevated pressure, which decreases in proximal direction, is applied in the distal area.

[0065] Moreover, an inertial sensor 35 can be connected on the prosthesis socket 1. The inertial sensor 35 acquires the position of the prosthesis socket 1 in space. Thereby, various types of information can be acquired, relating, for example, to the activity level, so that, depending on the respective detected activity, an adjustment of the contact pressure can occur by changing the inner circumference by opening or closing the tensioning devices 11, 12, 13.

[0066] In addition to the represented inertial sensor 35 or inertial angle sensor, which detects the orientation with respect to a fixed reference value, for example, the gravitational force, position sensors, acceleration sensors or other sensors can be arranged on the prosthesis socket 1 and coupled to the control unit 40, in order to obtain thereby information on the current activities. Also, a time switch device is arranged in the control unit 40, by means of which a time-controlled tensioning or relaxation of the tensioning devices 11, 12, 13 can be initiated.

[0067] FIG. 2 shows a variant of the invention in a diagrammatic representation in the opened state. Identical reference numerals designate identical components. From FIG. 2, one can see that the two lateral support elements 5, 6 are flipped open medially-laterally, resulting in a widened insertion opening 3. Instead of multiple separate tensioning devices 11, 12, 13, only a single tensioning device 11 in the form of a cable or a cord is arranged on the outer circumference of the prosthesis socket 1. The uninterrupted tensioning device 11 is guided along deflection rollers 22 which are arranged at different levels or heights in the proximal-distal direction. The tensioning device 11 is guided so that it meanders like a hose around the deflection rollers 22, wherein the tensioning device 11 is rolled on a roller 46, when an actuator 41 is driven in the form of a motor in a corresponding rotation direction. A motor current sensor 44 which measures the applied motor current is associated with the motor 41. By means of the motor current, it is possible to detect the motor torque and thus the force with which the tensioning device 11 is tensioned. Based on the tension force of the tensioning device 11, it can be concluded that there is applied contact pressure of the support elements 5, 6, 7, 8 onto the limb stump.

[0068] In addition to the motor current sensor 44, a pressure sensor 31 is arranged on the inner side of the frontal support element 7, in order to be able to transmit an additional measurement value to the control unit 40 which is not represented.

[0069] Not represented is a rearward support element which is also arranged on the end piece 2 so that it overlaps the medial and lateral support elements 5, 6, resulting in a complete enclosure of the limb stump which is not represented.

[0070] On the bottom of the receiving space on the end piece 2, the distal contact sensor 30 is arranged. The support elements 5, 6, 7, 8 are pretensioned directed outwardly or designed to be resilient, so that, after relaxation of the tensioning device 11 by unwinding the tensioning device 11 from the roller 46, the prosthesis socket 1 opens.

[0071] FIG. 3 shows the prosthesis socket 1 according to FIG. 2 in a closed state. A limb stump which is not represented has been introduced through the insertion opening 3 in the receiving space and has activated the contact sensor 30. The motor 41 was put in operation due to the activation signal of the control unit 40 which is not represented. The tensioning device 11 was wound on the roller 46, until the motor current sensor 44 or the pressure sensor 31 transmits a signal to the control unit 40, until the desired or preset limit pressure is reached. The control unit 40 has switched off the motor 41 and holds the tensioning device 11 in the tensioned state. The tensioning device 11 is guided perpendicularly along the medial support element 4 in the proximal-distal direction, frontally crosses in the lower area of the support elements 5, 6, 7, 8 and is deflected by deflection rollers 22, resulting in a zig-zag arrangement or a zig-zag course between the medial support element 5 and the lateral support element 6. In the proximal end area, the tensioning device 11 crosses again frontally and is coupled to the roller 46 and wound there. In addition to a permanent application of a holding current to the motor 41, it is possible and provided that a mechanical locking device is associated with the tensioning device 11, so that the motor 41 can be switched off. For the unlocking, the mechanical locking device can then be unlocked and the motor 41 can be activated in a reverse direction of rotation in order to open the prosthesis socket 1.

[0072] A variant of the embodiment according to FIG. 3 is shown in FIG. 4. Instead of only a single motor 41, three motors 41, 43 are secured at different heights in the proximal-distal direction on the prosthesis socket 1. A tensioning device 11, 12, 13 is associated with each motor 1. At the respective heights of the motors 41, 42, 43, pressure sensors 31, 32, 33 are arranged on the inner side of the prosthesis socket 1 in the receiving space, in the represented embodiment example on the frontal support element 7. The pressure sensors 31, 32, 33 can also be arranged on another support element 5, 6, 7, 8. In the same way, multiple sensors 31, 32, 33 can be arranged on each support element 5, 6, 7, 8; sensors can also be arranged at different heights on different support elements. It is also possible that, in addition to multiple sensors, multiple motor current sensors are associated with the respective motors 41, 42, 43.

[0073] All the motors 41, 42, 43 are connected to the control unit 40 which is not represented. If the sensor 30 or contact switch 30 is activated, the motors 41, 42, 43 are activated in such a manner that the tensioning devices 11, 12, 13 are wound, for example, on a motor shaft.

[0074] In FIG. 5, the closed state is represented, after the motors 41, 42, 43 have tensioned the tensioning devices 11, 12, 13. The support elements 5, 6, 7, 8 have been moved towards one another until the respective sensor 31, 32, 33 has displayed the predetermined contact pressure. Then, the motors 41, 42, 43 are switched off accordingly, and the prosthesis socket 1 is closed.

[0075] FIG. 6 shows a diagrammatic representation of the motor control. The control unit 40 is connected to the motor 41 or to the motors. Furthermore, the distal shaft connector 30, the manual switch 45, the pressure sensor(s) 31 and the inertial sensor 35 are connected to the control unit 40. Additional sensors or switches can also be connected to the control unit 40.

[0076] Based on the information from the sensors or commands via the switches, the control unit 40 activates the motor and tensions or relaxes the respective associated tensioning device.

[0077] The prosthesis socket according to the invention enables an automatic opening and closing by a corresponding activation or deactivation of an actuator or of multiple actuators which are connected to one or more tensioning devices, for example, to a lacing system or to multiple lacing systems. Instead of the activation of traction means which are rolled up and unrolled, the actuators can also activate and move other active elements such as levers, toothed wheels and toothed rods, sliders, spindles, spreading wedges, rings or clips, in order to bring about a change in inner circumference based on sensor data. In addition to a multi-part design of the prosthesis socket with several support elements which can be moved with respect to one another, the prosthesis socket can also be formed with only one single-part socket wall which has a slot or is wound up in the form of a coil like a torch. In a conical design, an opening or closing of the prosthesis socket can occur by shifting a ring or a clip along the longitudinal extent of the socket. Other measures for changing the inner circumference have already been described above. The prosthesis socket has the advantage, among others, that even in the case of variations of the limb stump volume or in the case of different limb stumps, a correct adjustment of the prosthesis socket to the limb stump can occur. Thus, it is no longer necessary to provide an individually molded prosthesis limb stump. In the basic state, the prosthesis socket is open, that is to say the support elements have been opened up. If the distal socket switch is activated, wherein the distal switch can be designed as a contact switch, a pressure switch, a mechanical switch or a proximity switch, the actuator is activated or the actuators are activated until the preset normal contact pressure of the socket wall or of the support elements on the limb stump has been reached. In this normal mode, the usual activities can be performed, for example walking or climbing stairs, in the case of a prosthesis of the lower extremity.

[0078] If high accelerations are detected over a certain time period, for example, by an acceleration sensor arranged on the prosthesis socket or on the prosthesis, one or more actuators are activated by means of the control unit, in order to reduce the inner circumference and optionally retension the tensioning device or the tensioning devices. The changing or tensioning process is continued until a preset contact pressure is reached, which appears suitable for the detected loading mode, for example, during sports activities.

[0079] As soon as elevated accelerations or forces are no longer detected and the absence of special loads has been detected over a certain time period, the contact pressure is reduced, in that the tensioning devices are released, volumes are reduced, the magnet is activated or deactivated, shape memory alloys are activated or deactivated, or other changes are carried out, until the normal pressure is reached again. The prosthesis socket opens due to resilience inherent in the support elements or the socket wall, or due to a separate reset device, for example, a spring, which loads the prosthesis socket with a force away from the limb stump.

[0080] If particularly small loads are detected again, or, on the other hand, if increases in contact pressure are detected, which are not caused by elevated acceleration values within the prosthesis or the prosthesis socket, for example, due to volume increases within the limb stump, the actuator or the actuators, starting from the normal mode, can relax the tensioning devices or other means in order to change the inner circumference, so that the prosthesis socket is in a relaxed mode with a lower contact pressure due to the increased inner circumference. This can occur, for example, during sitting or lying. Such states can be detected by means of acceleration sensors, position sensors and inertial sensors. If a movement start is detected, for example, by means of acceleration sensors, the motor tensions or the motors tension the tensioning device or the tensioning devices again, or the pump changes the volume in the inflatable pad, until the normal pressure is reached. The contact pressures can be determined again directly by means of pressure sensors or indirectly by means of motor current sensors or other sensors.

[0081] For the opening of the prosthesis socket, a manual switch is optionally activated, which relaxes the tensioning device or the tensioning devices to a maximum or activates the actuator to a maximum increase in inner circumference. If the actuators/motors or the actuator/motor fail(s), a mechanical unlocking device can be provided, by means of which the tensioning device can be completely relaxed or the inner circumference can be increased, to make it possible to take off the prosthesis socket.

[0082] Advantageously, the prosthesis socket is closed, as soon as it is displayed by means of the distal socket sensor or socket switch that the limb stump or the limb has been completely inserted. Alternatively or in addition to an automatic activation of the closure device, the socket can be closed by means of a separate close button, a magnetic switch, a smartphone, a tablet, a remote control or the like; for this purpose, the control unit is connected to a receiver module or to a corresponding contact with the switch. Voice control can also be provided, for opening or closing the prosthesis socket.

[0083] By alternating tensioning and relaxation of the tensioning devices, a massage effect can be provided for the received limb stump, which can be pleasant for the prosthesis user.

[0084] In addition to an adjustment based on activities, a tensioning or relaxation of the tensioning device in the context of a time program can occur, in order to avoid undesired pressure sites and injuries of the limb stump tissue. The sensors for the acquisition of the respective activities can be arranged both on the prosthesis socket and on the connected prosthetic device; the sensors located there, for example, inertial angle sensors, acceleration sensors, gyroscopes or angle sensors, can be used to bring about an adjusted change of the inner circumference, for example, by a tensioning or relaxation of tensioning devices.

[0085] FIG. 7 shows, in a detail view, a diagrammatic representation of a prosthesis socket 1 with three support elements 5, 6, 7, two of which are in each case arranged with mutual overlap. The support elements 5, 6 are arranged so that they form an inner circumference of the prosthesis socket, which is smaller than the outer circumference of a limb stump to be received or of a limb stump with prosthesis liner to be received. This can be brought about by a corresponding preformation or else by a pretensioning force which brings about a movement of the support elements 5, 6 in the direction of the limb stump. This can be, for example, a spring force which moves or pretensions the support elements 5, 6 hinged on an end piece in the direction of the limb stump which is not represented. On the third support element 7, an actuator 41 in the form of a motor is arranged, which is coupled to a roller 46 to which a tensioning element 11 in the form of a cable is connected. On the support element 7 to which the actuator 41 is connected, a pair of deflection elements 22 is also arranged, which are positioned on mutually facing sides of the roller 46. The cable 11 is connected to the roller 46 and guided around the deflection elements or deflection rollers 22, wherein the free ends of the cable 11, which are not connected to the roller 46, are again guided back in the direction of the roller 46. The guide of the cable 11 is thus U-shaped. In each case a free end is connected to the support element 5, 6 which overlaps the respective deflection roller 22. To the extent that the prosthesis socket consists of only two support elements, that is to say a gap or a slot is formed between a socket wall, which gap or slot is covered by the second support element 7, the free ends are in each case connected in the area of the mutually facing edges on the two sides of the roller 46.

[0086] FIG. 8 shows the construction of the spreading device according to FIG. 7 in the unopened state. The cable 11 is guided in opposite directions around the two deflection rollers 22, which are arranged spaced apart from one another, and back again to the edges of the two movable support elements 5, 6. There, the free ends of the cable 11 are connected to a respective connection site. The cable 11 is unrolled to a maximum; this means that the support elements 5, 6 are moved towards one another to a maximum, which results in a minimum inner circumference of the prosthesis socket. If the inner circumference is then to be increased, the actuator 41 in the form of a motor is activated, which is represented in FIG. 9. Due to the activation of the actuator 41, the roller 46 is set in rotation, the cable 11 is rolled up, and the connection sites with the free ends of the cable 11 are pulled in the direction of the respective deflection roller 22. Thereby, the gap or distance between the two support elements 5, 6 or the gap in a prosthesis socket wall is increased, whereby the inner circumference is increased, and the putting-on of the prosthesis socket is facilitated or the taking-off is facilitated or made possible. For the closing of the prosthesis socket 1, a reverse movement is brought about by the actuator 41, the cable 11 is unrolled, and the two support elements 5, 6 move again towards one another opposite the direction of the arrow according to FIG. 9. Thereby, the inner circumference is decreased, the pressure on the limb stump arranged within the prosthesis socket is increased, and an improved fit is achieved.

[0087] In principle, it is possible and provided that the above-described embodiment examples also function and are operated without sensors and without a control device, wherein the actuator 41 can then be activated either by a motor or manually; in particular, the manual opening or the opening by motor without sensors and control devices by activation of a motor or by manual activation of an actuator, for example of a toothed rod, of a slider, a threading, a roller, an adjustment of a spreading element, for example, of a ring, a clip or the like, makes it possible to increase the inner circumference. The reset occurs advantageously by a resilient reset force which is exerted on the opened prosthesis socket. A design without a sensor represents an independent solution and invention.