Self-supporting forearm crutches

Description

TECHNICAL AREA

[0001] The present disclosure relates to a forearm crutch. TECHNICAL BACKGROUND

[0002] It is well known that crutches are intended to enable people with temporary walking difficulties to lead a daily life with minimal restrictions. For example, crutches reduce the physical load on an injured leg, knee, and / or foot while walking, thus allowing the injury to heal despite movement. Typically, forearm crutches are used. People often rely on crutches, especially forearm crutches, after surgery on their lower extremities. In cases of unilateral injuries, such as only affecting the left or right leg, two crutches are regularly used to prevent postural problems and / or excessive strain during the healing phase. Some people require crutches permanently.

[0003] The classic design of a forearm crutch is partly due to medical reasons and is often unsuitable for leaning against a wall or similar surface. For example, the crutches can easily slip and fall to the floor. This can be problematic for users, as they have to reach down for the crutch several times a day – a process that is not only unpleasant but also potentially dangerous for people with physical limitations. Such situations can arise, for example, in the bathroom at the sink, in the kitchen while cooking, or while paying at a supermarket checkout.

[0004] Several solutions addressing similar problems are already known. For example, multi-legged crutches or rotating crutches that can be assembled into a self-standing frame, or crutches with an enlarged base, are known. See, for example, DE 10 2020 101 153 A1, US 5 992 434 A, DE 20 2004 008 364 U1. Furthermore, crutches with suction cups or hooks for attaching them to a wall, for example, are known. See, for example, DE 296 08 710 U1, GB 2 384 982 A1, DE 203 03 561 U1, DE 203 01 525 U1, DE 87 15 042 U1, DE 198 21568 A1, DE 203 17 281 U1, DE 102 39 219 A1, DE 203 15 153 U1, DE 20 2004 007 449 U1, DE 20 2004 011 241 U1, DE 20 2005 005 812 U1, EP 3 207 914 A1, GB 2 555 588 A1. There are some walking sticks known that are designed to prevent the user from slipping while walking, for example by creating a vacuum.See, for example, US 2013 / 032185 A1, CN 203 618 903 U, CN 209 090 156 U, CN 214 432 363 U, CN 213 218 823 U, CN 215 081 750 U, CN 2840753 Y, CN 210 673 638 U, CN 212 165 124 U, CN 213 849 100 U, CN 215 303 529 U. CN 206 964 214 U discloses an "intelligent" crutch designed to prevent the user from falling. The crutch features a ring with rollers and a suction cup that can be evacuated by an electric pump. If sensors detect a tilting of the crutches, this is interpreted as the user falling over, the suction cup is lowered and evacuated to secure the crutch to the ground. CN 212 165 124 U discloses a non-slip, one-handed walking stick comprising a stick body, an inner shaft, and a loop handle. A handle is arranged at the top of the stick body, the lower end of the stick body is connected to a suction cup body, and a vacuum mechanism is arranged within the suction cup body.The inner stock is arranged in the stock body and connected to it in an up-and-down movable manner; the sleeve stock is arranged on the outside of the stock body in a sleeve arrangement and is connected to the stock body via a locking mechanism in a lockable, up-and-down movable manner.

[0005] Existing state-of-the-art solutions are only suitable for everyday use to a limited extent.

[0006] The purpose of the present disclosure is therefore to provide a forearm crutch, in particular a medical forearm crutch, which offers the user improved comfort while taking into account the user's limited mobility. BRIEF DESCRIPTION OF THE INVENTION

[0007] This problem is solved by a forearm crutch according to claim 1. Further embodiments, configurations, and advantages will become apparent from the dependent claims and the following description. Embodiments in which a pump is arranged only in a handle serve only for illustration and do not correspond to the subject matter of claim 1.

[0008] According to one aspect of the present disclosure, a forearm crutch comprises a support tube with a central axis, an upper end, and a lower end, a handgrip, and a forearm support, which are arranged offset from one another at the upper end of the support tube. At the lower end of the support tube, a base support element with a circular base contact surface having a diameter between 50 mm and 80 mm is arranged. The forearm crutch further comprises a holding device for generating a vacuum between the base support element and a floor when the forearm crutch is placed on the floor with the base support element, in order to hold the forearm crutch upright on the floor and to secure it against tipping over, wherein the holding device comprises a pump and an actuating element for actuating or activating the pump.The holding device may have a volume open towards the floor on which the forearm crutch is placed during use.

[0009] The pump is located within the support tube and features a slide valve that is movable within a pump tube. This pump tube is arranged coaxially to the central axis and radially inward with respect to the second tube. The user manually initiates the pumping action by pressing the handle toward the base support, thereby causing a relative movement along the central axis between the pump tube and the slide valve. One or more counterweights are located in the handle and / or the forearm support to adjust the center of gravity of the forearm crutch to a region around the central axis with a diameter smaller than the diameter of the base support.

[0010] The details of one or more aspects of the disclosure are set forth in the accompanying figures and the following description. Other features, objects, and advantages of the principles described in this disclosure will become apparent from the description and drawings, as well as from the claims. BRIEF DESCRIPTION OF THE FIGURES

[0011] The invention will now be explained in more detail with reference to embodiments, without these being intended to restrict the scope of protection defined by the claims.

[0012] The accompanying drawings illustrate embodiments and, together with the description, serve to explain the principles of the invention. The elements of the drawings are relative to one another and not necessarily to scale. Identical reference numerals denote similar or identical parts. Figure 1 shows a view of a medical forearm crutch according to one embodiment. Figure 2 shows a schematic sectional view of a medical forearm crutch according to one embodiment. Figure 3 shows a schematic sectional view of a medical forearm crutch according to one embodiment. Figure 4 shows a schematic sectional view of a medical forearm crutch according to one embodiment. DETAILED DESCRIPTION

[0013] The principles described in this disclosure enable a forearm crutch to remain independently in place on a floor by generating a vacuum such that the crutch adheres to the floor, or is pressed against it. This creates a holding force sufficient to reliably fix the crutch to the floor so that it can stand on its own, i.e., without further support from the user or an aid, and can be released by the user without the crutch falling over. Smaller external forces and / or moments acting on the crutch, such as a weak gust of wind, cannot cause it to fall when the holding device with the vacuum engaged is activated.

[0014] The forearm crutch according to one embodiment has, in particular, a first tube and a second tube for insertion into the first tube, such that the first tube and the second tube have a common coaxial central axis. A "tube" within the meaning of this disclosure refers in particular to an elongated hollow body, wherein the elongated hollow body may have a circular cross-section. Other cross-sections are also conceivable. In some embodiments, the second tube may be designed to be displaceable relative to the first tube in such a way as to allow height adjustment.According to some embodiments, the second tube has an outer diameter that is essentially the same as the inner diameter of the first tube, whereby the outer diameter of the second tube may be slightly smaller than the inner diameter of the first tube to allow the user to move the second tube within the first tube as needed without additional tools. The first tube and the second tube can together form the support tube.

[0015] Furthermore, the forearm crutch comprises a handgrip and a forearm support, which are positioned offset from each other at the upper end of the first tube. The handgrip is designed so that a user can support their entire weight on it, with the forearm, for example, slightly below the elbow, being partially enclosed by the forearm support. The forearm support features, for example, a semi-circular recess into which the user places their forearm when grasping the handgrip.

[0016] The handgrip and forearm support can be rigidly connected, for example, by a bridge or tube. This mechanical connection between the handgrip and forearm support can be slightly inclined relative to the first tube, so that the mechanical connection runs slightly backward, i.e., slightly away from the handgrip, so that an angle of more than 90° is formed between the handgrip, and thus the user's hand, and the mechanical connection, and thus the forearm encompassed by the forearm support.

[0017] A base support element is located at the lower end of the second tube. This base support element may, for example, include grooves, making it more flexible and preventing small loose objects on the floor, such as dust and stones, from interfering with the stability of the forearm crutch.

[0018] Forearm crutches differ from other crutches primarily in that they feature a forearm support that rests against and partially surrounds the forearm, providing support when the user grasps the handle. The forearm support is therefore offset from the handle and, when used correctly, is positioned above it. This stabilizes the user's forearm relative to the crutch, thus relieving strain on the wrist, as fixing the forearm above the handle prevents the wrist from bending at an angle.

[0019] The forearm crutch also includes a holding device for generating the negative pressure required to independently hold the forearm crutch on the ground, with an actuating element. When actuated, the actuating element activates the holding device to generate the negative pressure. The negative pressure can be generated within a volume inside the forearm crutch and / or holding device. This volume, in which the negative pressure is generated relative to the surrounding environment, is sealed off from the ground when the forearm crutch is placed on the ground as intended. The holding device is essentially arranged within cavities of the forearm crutch in such a way that the external visible geometry of the forearm crutch remains essentially unaffected by the holding device.

[0020] The actuable element can be, for example, a button, a lever, or a similar element that can be actuated manually by the user, for example, by means of a finger or thumb when the user's hand grips the handle. Actuation of the actuable element activates the holding device for generating the vacuum. For the purposes of this disclosure, the term "activate" is to be understood as the immediate generation of the vacuum and / or the preparation of the holding device for the imminent generation of the vacuum.

[0021] In some embodiments, the actuating element can be located on an end face of the handle. This prevents the user from unintentionally activating the element while using the forearm crutch. Furthermore, the user's thumb can easily reach the actuating element, even when the user's weight is still on the forearm crutch and they are gripping the handle.

[0022] According to some embodiments, the center of gravity of the forearm crutch can lie on the central axis of the first or second tube, or of the support tube. According to the invention, corresponding counterweights are arranged on and / or inside the forearm crutch for this purpose. Since, due to the overall shape of the forearm crutch, its center of gravity does not necessarily lie on the central axis, the center of mass distribution can be modified by the (additional) counterweights so that the center of gravity lies at least close to the central axis. If the center of gravity of the forearm crutch lies on or near the central axis, the forearm crutch will always stand on a flat surface independently, provided no external forces or moments act upon it.

[0023] The base element has a circular base surface with a diameter between 50 mm and 80 mm, particularly 50 mm and 70 mm, preferably 50 mm and 60 mm, and especially between 52 mm and 58 mm. It is also possible for the diameter to be between 60 mm and 80 mm, for example, between 65 mm and 80 mm. It has been found that a base element with a diameter in one of the aforementioned ranges facilitates the independent stability of the forearm crutch. At the same time, it ensures that the base element is not too large and does not obstruct the user's walking path or interfere with the movement of the legs or feet. In combination with an embodiment in which the center of gravity of the forearm crutch is additionally located on or near the central axis, it has been found that this combination further improves the independent stability of the forearm crutch.This can be advantageous on unfavorable surfaces for generating negative pressure and / or when the forearm crutch is subjected to greater external forces. Furthermore, a smaller pressure difference to the surrounding environment may be sufficient for the forearm crutch to remain in place independently.

[0024] In some embodiments, the negative pressure can be created by drawing air out of the volume. The volume preferably has a relatively large opening towards the bottom in order to generate the highest possible contact pressure when a negative pressure exists within the volume. For example, the volume can be formed by a cavity open towards the bottom.

[0025] In embodiments, the negative pressure can be generated by at least one pumping action. For example, air can be expelled from the volume by a reduction in volume caused by the pumping action, through a valve. The valve can prevent air from flowing back into the volume when the volume is increased again. For the purposes of this disclosure, the term "valve" also includes valve circuits and / or multiple individual valves. The size of the volume can be variable, for example, if the volume itself is part of a pump. However, the size of the volume can also be constant and, for example, be formed by a cavity open at the bottom, if the air is removed from the volume by a separate pump.

[0026] According to some embodiments, the at least one pumping movement can be performed electromechanically (not part of the present invention, but used for illustrative purposes only). For example, the holding device of the forearm crutch can comprise an energy carrier and an electrically operated pump (not part of the present invention, but used for illustrative purposes only). The electrically operated pump can, for example, displace and / or extract air from the volume as soon as the holding device is activated.

[0027] According to the invention, the at least one pumping movement is performed manually. For example, the user can perform the pumping movement manually to create a vacuum. The at least one pumping movement is performed by at least one relative movement between a pump tube and a slide (piston or plunger) arranged coaxially and internally with respect to the pump tube. For example, the slide can be configured to displace air from the pump tube and simultaneously prevent air from flowing into the pump tube. The pump tube and / or the slide can have a circular cross-section. Other cross-sections are also conceivable. The pump tube can terminate at the base when the forearm crutch is placed on the ground and / or at the base support element. For example, the pump tube can pass through the base support element.The pump tube can widen towards the bottom to create the volume in which the vacuum is to be generated.

[0028] Repeated actuation of the actuator can, for example, increase the generated vacuum. A valve can be provided that prevents air from flowing in while simultaneously allowing air to continue being displaced from the volume.

[0029] In some embodiments, the pump tube can be arranged coaxially to the central axis and radially inward with respect to the second tube, so that the relative movement is performed along the central axis. This can allow for a greater stroke, so that a comparatively large vacuum is generated with a single pumping motion to hold the forearm crutch in place independently. For example, the slider can be located on the handgrip and / or on the forearm crutch.

[0030] The pump is located in the support tube and features a sliding slide within a pump tube. Pumping is initiated manually by the user by pushing the handle towards the base support, thus creating a relative movement between the pump tube and the slide. For example, the user can shift their weight onto the handle to move the slide within the pump tube, thereby expelling air. A return mechanism then moves the slide back in the opposite direction of pumping, creating a vacuum within the pump tube and consequently in the base support.

[0031] In some embodiments, the pump tube and / or the slide valve can be connected to at least one return element. The return element can, for example, return the slide valve and / or the pump tube to its original position after the relative movement has been performed.

[0032] According to some embodiments, the actuated element can release a safety device in the actuated state, thus releasing the relative movement along the central axis.

[0033] In some embodiments, the holding device may further include a bottom sealing element configured to seal against the ground. For example, the bottom sealing element may be made of an elastically deformable sealing material. In some embodiments, the bottom sealing element may be connected to the pump pipe.

[0034] In some embodiments, the bottom sealing element can be designed to be axially displaceable. For example, in the unactuated state of the actuated element, the bottom sealing element can have an axial distance from a base contact surface of the base contact element. In some embodiments, the pump pipe and the bottom sealing element can be designed to be axially displaceable together.

[0035] The following section refers in detail to embodiments of the disclosure, some examples of which are illustrated in the figures. Each example serves to illustrate the disclosure, not to limit it. For example, features that are shown or described as part of embodiments can be used with other embodiments to produce further embodiments.

[0036] Figure 1 Figure 1 shows a forearm crutch according to some embodiments. The forearm crutch comprises a support tube 100 with an upper end and a lower end, a handgrip 130, and a forearm support 140, which are arranged offset from each other at the upper end of the support tube 100, and a ground support element 150 arranged at the lower end of the support tube 100. The handgrip 130 and the forearm support 140 are rigidly connected to each other via a web 145.

[0037] The forearm crutch further comprises a holding device for generating a vacuum between the base support element 150 and the floor when the forearm crutch is placed on the floor with the base support element 150, in order to hold the forearm crutch upright on the floor and secure it against tipping over. The holding device comprises a pump 270 and an actuating element 210 for actuating or activating the pump 270.

[0038] The base support element 150 can be slid onto the lower end of the support tube 100 and has a base body made of an elastic material, for example, rubber. The base support element 150 has a cavity 155 open towards the floor, which is in fluidic communication with the pump 270. By actuating the pump 270, a vacuum can be created in the cavity 155 when the forearm crutch is placed on the floor with the base support element 150. This holds the forearm crutch to the floor and prevents it from tipping over. The cavity 155 forms the volume in which the vacuum is generated.

[0039] The bridge 145 and the forearm support 140 extend obliquely with respect to the central axis of the support tube 100 to enable the user to use the forearm crutch in an anatomically adapted manner. The handgrip 130 extends approximately perpendicularly from the central axis. This results in a center of gravity for the forearm crutch that does not coincide with the central axis and prevents the forearm crutch from standing freely.

[0040] To support the fixation of the forearm crutch to the ground and enable free standing, the forearm crutch has one or more counterweights 160. These can be integrated, for example, into the handgrip 130 and / or the forearm support 140. The counterweights 160 serve to adjust the center of gravity of the forearm crutch so that it lies close to the central axis, which is defined by the support tube 100. Specifically, the center of gravity is adjusted so that it lies within a small-diameter circular area around the central axis. Assuming that the base element 150 has a circular base with a diameter of [missing information], then the center of gravity of the forearm crutch lies within a region around the central axis with a diameter smaller than the diameter of the base.Preferably, the diameter of the circular area is less than half the diameter of the base contact area, so that the center of gravity is relatively close to the central axis. Particularly preferably, the center of gravity of the forearm crutch lies on the central axis.

[0041] Figure 2Figure 1 schematically shows a forearm crutch according to several embodiments in a sectional view. The forearm crutch comprises a first tube 110 with a central axis 101, an upper end 111, and a lower end 112, and a second tube 120, the upper end of which is inserted into the lower end 112 of the first tube 110. The second tube 120 can be moved relative to the first tube 110 and secured with a locking element 121 to prevent any relative axial movement between the first tube 110 and the second tube 120. By removing the locking element 121, the user can adjust the height, for example, in increments. Once the desired height is set, the user can reinsert the locking element 121.

[0042] The first pipe 110 and the second pipe 120 together form the support pipe 100, and can therefore also be used in the Figure 1The embodiment shown is provided for. The two-part design of the support tube 100 allows for easy adjustment of the height of the handgrip 130, thus adapting the forearm crutch to the individual user.

[0043] Furthermore, the forearm crutch comprises the handgrip 130 and the forearm support 140 (only partially shown here), or the bridge 145, which are arranged offset from each other via the bridge 145 at the upper end 111 of the first tube 110. The base support element 150 is arranged at a lower end of the second tube 120. The base support element 150 can, for example, be made of rubber to prevent the forearm crutch from slipping. The base support element 150 can also have one or more grooves 151. The diameter of the base support element 150 is 50 mm to 80 mm, and can in particular be 50 mm to 70 mm or 60 mm to 80 mm.

[0044] The forearm crutch has a holding device 200 for generating a vacuum to hold the forearm crutch independently on a surface 102. The holding device 200 includes an actuating element 210 which, when actuated, activates the holding device 200 to generate the vacuum. The actuating element 210 is arranged on an end face of the handle 130, for example as shown in Figure 1 shown. The forearm crutch is designed such that its center of gravity lies on the central axis 101. The following can be used for this purpose: Figure 1 The counterweights shown, for example 160, can be integrated into the forearm support 140.

[0045] The in Figure 2The forearm crutch shown comprises a slide 220, which may, for example, be designed as a piston. The slide 220 is connected to the handle 130. The slide 220 has a sealing element 221 that seals against a pump tube 230, in particular against an inner surface of the pump tube 230. The pump tube 230 is mounted coaxially to and within the first tube 110. A bottom sealing element 240 is arranged at a lower end of the pump tube 230. Furthermore, a valve 250 is arranged on the pump tube 230. A dust seal 260 may be provided against an outer surface of the pump tube 230 to prevent the ingress of loose elements from the base 102 into the first tube 110 and / or the second tube 120. The pump tube 230, together with the bottom sealing element 240, is arranged to be axially displaceable. In particular, the pump tube 230 can be axially displaceable on the second tube 120, so that height adjustment remains possible.

[0046] The floor sealing element 240 is arranged within the floor support element 150 and can be considered part of the floor support element 150. The floor sealing element 240 is slidably arranged within the floor support element 150 along the central axis 101. During normal use, the floor sealing element 240 is axially retracted from the floor 102 and does not come into contact with the floor 102. The user's load rests on the floor support element 150 surrounding the floor sealing element 240.

[0047] If the forearm crutch is to be stored freestanding, the pump tube 230, together with the base sealing element 240, is moved axially towards the base 102 until the base sealing element 240 makes contact with the base 102. Air is then forced out of the pump tube 230 through the slide 220 and escapes, for example, at the base 102. After the slide 220 is released, it moves back to its initial position, creating a vacuum inside the pump tube 230, which acts against the base 102 through the base sealing element 240.

[0048] At the in Figure 2In the forearm crutch shown, a safety device 211 can be released for this purpose by actuating the actuating element 210. This activates the holding device 200 for generating the vacuum, thus preparing for its creation. Once the safety device 211 is released, the user can exert a force, e.g., on the handle 130, which moves the slide 220 along the central axis 101 towards the base 102. The sealing element 221, the pump tube 230, and / or the slide 220 can be designed such that the force initially displaces the pump tube 230 with the base sealing element 240 axially towards the base 102 until the base sealing element 240 rests against the base 102. If force continues to be exerted, the slide 220 then moves relative to the pump tube 230, thereby forcing air at the base or through the valve 250 into the environment.The volume in the pipe is limited by the pump pipe 230, the sealing element 221, the bottom sealing element 240 and the bottom 102.

[0049] A return element 280 can then be provided on the slide 220, on the pump tube 230, and / or on the handle 130, for example, a spring surrounding the slide 220, which is supported on one side by the pump tube 230 and on the other side by the handle 130. The return element 280 can increase the volume in the pump tube 230 again by performing a relative movement in the opposite direction to the pumping movement, without retracting the pump tube 230. For example, the user can also manually perform the relative movement in the opposite direction. Since a seal against the base 102 is created by the bottom sealing element 240, no air can flow into the increasing volume. A negative pressure is created, so that the bottom sealing element 240 remains pressed against the base 102. In preferred embodiments, the return element moves the handle 130 back into a locked position, i.e.,into the position in which the fuse 211 can be extended again without the pump tube 230 being moved back.

[0050] The relative movement in the opposite direction may, for example, require less force than the relative movement towards the ground 102. This can be achieved, for example, by means of a special sealing element 221 and / or an adapted bearing of the pump pipe 230.

[0051] To detach the forearm crutch from the base 102, the user can, for example, pull the forearm crutch off the base 102 or tilt it. An additional resetting element may be provided, for example, to re-establish an axial distance between the base sealing element 240 and the base 102 after the negative pressure has been equalized. Alternatively, no resetting element may be provided for this purpose. Resetting may be achieved, for example, solely through the axial displacement and standard use of the forearm crutch.

[0052] The forearm crutch may also have ventilation openings and / or vent openings. These ventilation openings and / or vent openings can be opened and / or closed by actuating the actuating element 210 and / or when the actuating element 210 is returned to its unactuated state.

[0053] A separate bottom sealing element 240 separates the functions. The bottom support element 150 bears the load during normal use. The bottom sealing element 240, on the other hand, seals the cavity of the pump pipe 230. The material of the bottom support element 150 and the bottom sealing element 240 can therefore be adapted to their respective functions. For example, the material of the bottom sealing element 240 can be softer than that of the bottom element 150, thus providing a better seal. Since the bottom sealing element 240 does not come into contact with the ground 102 during normal use, nor does it bear the load exerted by the user, the bottom sealing element 240, which is made of a soft and elastic material, is not subject to wear. The materials of the bottom sealing element 240 and the bottom support element 240 can therefore each be elastic, but with different degrees of hardness.

[0054] Figure 3 Figure 1 schematically shows a forearm crutant according to several embodiments in a sectional view. The forearm crutant features, as already mentioned in connection with Figure 2 The text describes a first tube 110, a second tube 120, a handle 130, and a forearm support 140. Furthermore, the forearm support includes a base support element 150 with grooves 151. The base support element 150 may include the base sealing element 240.

[0055] The bottom sealing element 240 can have a lip 156 which is bent around a base support surface of the base support element 150, thereby achieving a particularly good seal between the pump pipe 230 and the base 102 (not shown here). The pump pipe 230 can seal against a dust protection seal 260. The dust protection seal 260 can be enclosed by the base support element 150.

[0056] The pump tube 230 can be fixedly mounted to the base support element 150 and / or to the second tube 120. Moving the pump tube 230 relative to the base support element 150 is not intended. However, height adjustment of the support tube is still possible. For this purpose, the pump tube 230 can be made shorter and the slide 220 longer, thus still engaging with the pump tube 230. This leaves sufficient clearance when the first and second tubes 110 and 120 are moved relative to each other. For height adjustment, the locking element 121 can be inserted into aligned openings in the first tube 110 and the second tube 120.

[0057] In Figure 3A maximum length of the support tube 110 is discernible, at which point the second tube 120 is inserted into the first tube 110 only by a minimum length necessary to maintain stability. If the forearm crutch is to be lower, the second tube 110 is inserted deeper into the first tube 120. Simultaneously, the slider 220 is inserted deeper into the pump tube 230. Since the pump tube 230 is shorter and approximately only the same length as the second pump tube 120, sufficient adjustment remains for the height of the forearm crutch.

[0058] Furthermore, the forearm crutch can be made of Figure 3 the same construction as the forearm crutch Figure 2 exhibit.

[0059] Figure 4(not part of the present invention, but serves only for illustration). A forearm crutch according to some embodiments is shown schematically in a sectional view. The forearm crutch can have the basic structure as shown in Figure 3 exhibit the embodiment shown.

[0060] However, this embodiment includes a holding device 200 with an electric pump 270 (not part of the present invention, but serves only for illustration). When the actuated element 210 is actuated, the pump 270 generates a vacuum by drawing air from the pump tube 230. The forearm crutch may have vent holes through which the air drawn in by the pump 270 can escape.

[0061] To release the forearm crutch from the base 102 after the vacuum has been created, the user can manually pull or tilt the forearm crutch off the base 102. It is also conceivable that the actuating element 210 allows for pressure equalization upon a second actuation. This second actuation can correspond to an actual second actuation or another type of actuation, e.g., a stepwise actuation.

[0062] The foregoing description presents a forearm crutch with reference to specific examples. It should be noted that various aspects and embodiments disclosed herein can be combined in ways other than those shown in the figures. It is assumed that various modifications to the aforementioned embodiments can be made without deviating from the scope of the disclosure and the following claims. REFERENCE MARK LIST

[0063] 100 Support tube 101 Center shaft 102 Base 110 First tube 111 Upper end of first tube 112 Lower end of first tube 120 Second tube 121 Locking element 130 Handle 140 Forearm support 145 Web 150 Base support element 151 Grooves 155 Cavity 156 Lip 160 Counterweight 200 Holding device 210 Actuable element 211 Safety device 220 Slide 221 Sealing element 230 Pump tube 240 Base sealing element 250 Valve 260 Dust seal 270 Pump 280 Return element

Claims

1. Forearm crutch, comprising: a support tube (100) with a central axis (101), an upper end and a lower end; a hand grip (130) and a forearm support (140) arranged offset from each other at the upper end of the support tube (100); a floor support element (150) arranged at the lower end of the support tube (120) with a circular floor resting surface having a diameter between 50 mm and 80 mm; and a holding device (200) for generating an underpressure between the floor support element (150) and a floor (102) when the forearm crutch is placed on the floor (102) with the floor support element (150) in order to hold the forearm crutch free-standing on the floor (102) and prevent it from falling over, wherein the holding device (200) comprises a pump (270) and an actuable element (210) for actuating or activating the pump (270); wherein the support tube comprises a first tube (110) with a central axis (101), an upper end (111) and a lower end (112), and a second tube (120) which is inserted with its upper end into the lower end (112) of the first tube (110); wherein the pump is arranged in the support tube and comprises a pusher (220) which can be displaced in a pump tube (230), wherein the pump tube (230) is arranged coaxially with the central axis (101) and radially inside the second tube (120), wherein a pumping operation can be performed manually by the user by pressing the hand grip (130) towards the floor support element (150), thereby causing a relative movement along the central axis (101) between the pump tube (230) and the pusher (220); and wherein one or more counterweights (160) are arranged in the hand grip (130) and / or in the forearm support (140) in order to adjust the centre of gravity of the forearm crutch in an area around the central axis (101) with a diameter smaller than the diameter of the floor resting surface.

2. Forearm crutch according to claim 1, wherein the actuable element (210) is provided on one end face of the hand grip (130).

3. Forearm crutch according to one of the preceding claims, wherein the diameter of the circular area is in particular less than half the diameter of the floor resting surface, wherein the centre of gravity of the forearm crutch is in particular on the central axis (101).

4. Forearm crutch according to one of the preceding claims, wherein the holding device (200) and / or the floor support element (150) further comprises a floor sealing element (240) configured to seal against the floor (102).

5. Forearm crutch according to claim 4, wherein the floor sealing element (240) is designed to be axially displaceable, and wherein the floor sealing element (240) has an axial distance from a floor resting surface of the floor support element (150) in an unactuated state of the actuable element (210).

6. Forearm crutch according to claim 4 or 5, wherein the floor support element (150) surrounds the floor sealing element (240).

7. Forearm crutch according to one of the preceding claims, wherein the hand grip (130) and the forearm support (140) are arranged offset from each other at the upper end (111) of the first tube (110); the floor support element (150) is arranged at a lower end of the second tube (120); and the length of the forearm crutch is adjustable by displacing the second tube (110) within the first tube (110).

8. Forearm crutch according to one of the preceding claims, wherein the relative movement between the pump tube (230) and the pusher (220) is locked by a safety device (211) which can be released by the user via the actuable element (210), thereby releasing the relative movement.

9. Forearm crutch according to one of the preceding claims, wherein the pump tube (230) is movably mounted in the second tube (120) and, when the hand grip (130) is pressed towards the floor support element (150), is pushed towards the floor (102) until the pump tube (230) comes into contact with the floor (102) via the floor sealing element (240).