EP3797748A1

EP3797748A1 - Orthopaedic cushion

Info

Publication number: EP3797748A1
Application number: EP20195398.1A
Authority: EP
Inventors: Eric De Croock; Johan Aerts; Willem Franssen; Dimitri De Martelaere
Original assignee: Albatros NV
Current assignee: Albatros NV
Priority date: 2019-09-25
Filing date: 2020-09-10
Publication date: 2021-03-31
Anticipated expiration: 2040-09-10
Also published as: BE1027593B1; BE1027593A1; EP3797748B1

Abstract

The present invention relates to an orthopaedic cushion (1), comprising:
- a shaped foam block (2) which is provided with a holding cavity (3) in order to position and support a body part;
- a ventilator (4) for sucking in air and expelling this air via an outlet (5);
- an air duct (6) for the passage of air from the outlet (5) to an outlet opening (7) at the bottom of the holding cavity (3);
- a three-dimensional fabric (9) which is fitted over the outlet opening (7) in the holding cavity (3) and up to lateral sides (10) of the holding cavity (3) for discharging air via these lateral sides (10).

Description

The present invention relates to an orthopaedic cushion which comprises a shaped foam block which is provided with a holding cavity for holding a body part in order to position and support this body part.
Such an orthopaedic cushion is an individual aid which is fully adapted to the shape of the body part of the patient to be positioned and supported in order to obtain a good and comfortable position. To this end, the holding cavity is shaped in accordance with the shape of the respective body part.
More specifically, this may be a lying orthosis, in the shape of a back-lying orthosis or a stomach-lying orthosis or a side-lying orthosis. Still more specifically, such a lying-orthosis may be configured as a dynamic lying orthosis.
In addition, the present invention may also be suitable for an abduction cushion or a sitting orthosis or a relaxing orthosis which provides comfortable support to the body in seated position or in semi-recumbent position, etc.
The foam block of such an orthopaedic cushion is typically made from an open-cell cold foam, i.e. a foam having a high resilience. This may to this end be made from for example polyether. Typically, this foam block is formed by milling it to size to fit the shape of the patient.
The foam block of such an orthopaedic cushion to which the invention relates may be composed of various pieces, but these pieces are then assembled and together form one joined-up unit. These pieces together form one foam block.
One such foam block is typically coated with an elastic coating in order to make the unit smooth, soft and impermeable to moisture.
By using different densities of foam, it is possible to achieve a suitable correction and pressure reduction.
Furthermore, the unit is typically provided with a cover over it made of towelling to protect the orthopaedic cushion and render it comfortable for the patient.
Despite the softness of the foam block, the coating and the cover of such an orthopaedic cushion, such a cushion is often still deemed to be uncomfortable. The reason for this is that the respective body part is partly hemmed in so as to ensure satisfactory support and positioning thereof. As a result thereof, this body part is more susceptible to sweating. Excessive heat and moisture may have a significant effect on the risk of developing decubitus.
It is an object of the present invention to increase the comfort of such an orthopaedic cushion.
This object of the invention is achieved by providing an orthopaedic cushion, comprising:

a shaped foam block which is provided with a holding cavity for holding a body part in order to position and support this body part;
a ventilator for sucking in air and expelling this air via an outlet;
an air duct for the passage of air from the outlet of the ventilator and expelling this air via an outlet opening at the bottom of the holding cavity; and
a three-dimensional fabric which is fitted over the outlet opening in the holding cavity and up to the lateral sides of the holding cavity for diffusing air from the aperture and discharging this air via these lateral sides.

The three-dimensional fabric may be fitted over the entire holding cavity, but may also be fitted in a more limited zone of this holding cavity, between flanks of this holding cavity.
By means of the three-dimensional fabric through which air is blown using the ventilator, air is thus diffused across the holding cavity from the outlet opening, in which case the body heat of the supported body part is discharged, together with the air, at least partly via the flanks. If desired, some of the air may also be diffused evenly via the three-dimensional fabric to an adjacent zone of the holding cavity, via which adjacent zone this air may then be discharged further.
Such a three-dimensional fabric has a top layer and a bottom layer with shaped spacers in between, between which a space which allows through-flow of air is present. Even when this three-dimensional fabric is depressed, this space continues to allow the through-flow of air. Thus, the air is not blocked when the fabric is depressed. If a patient is lying in the foam block, there is a pressure build-up which ensures that the air stream is evenly distributed. As a result, there are no cold zones, but instead a constant, proportional air stream. Such a three-dimensional fabric may to this end be designed to have, for example, a three-dimensional honeycomb structure. An example of such a three-dimensional fabric is, for example, known by the brand name Aerosleep.
As is the case with the prior art, the foam block here may also be provided with a coating in order to render this foam block smooth, soft and impermeable to moisture.
As is the case in the prior art, such an orthopaedic cushion may furthermore also be provided with an air-permeable cover. Such an air-permeable cover does not form any limitation with regard to the air stream in the desired zone.
The ventilator is preferably a centrifugal ventilator.
An orthopaedic cushion according to the present invention is furthermore preferably provided with an aperture at the bottom of the holding cavity in which said outlet opening is provided in order to increase the diffusion of the air.
In this case, this aperture is furthermore preferably provided with an air-distributing element for distributing air from the air duct across several outlet openings. The three-dimensional fabric is then preferably fitted over these outlet openings in order to diffuse the air from these outlet openings.
In this case, the air-distributing element is preferably provided in the aperture so as to be removable. By providing this air-distributing element so as to be removable, it is easier to clean than when it is fixedly fitted in the foam block.
Preferably, such an air-distributing element comprises:

a base which is arranged at the bottom in the aperture and comprises a bottom which is delimited at the periphery of the bottom by a first upright edge and which comprises a passage opening in the bottom, wherein this passage opening is delimited by a second upright edge of the base and is connected to the outlet opening; and
an insert which is detachably arranged at the top of the base and which delimits said outlet openings.

Such a base then forms a collecting tray for moisture in order to limit the amount of moisture entering the air duct and thus further improve the cleanability of the orthopaedic cushion. By detachably providing the insert at the top of the base, this insert can easily be released from the base during cleaning of the air-distributing element in order to be able to pour out moisture which has collected in the base.
In order to fit the insert detachably in the base, it is configured so as to be complementary with this base.
More specifically, the base of such an air-distributing element may be configured to be dish-shaped.
Such an insert is preferably made of foam material in order to make the unit consisting of the air-distributing element and the foam block as comfortable as possible for the patient.
To this end, this insert may for example be produced as a thermoformed part, for example from closed-cell polyethylene (PE) foam.
Such an insert made of foam material may additionally, if desired, be provided with a coating to render this insert smooth, soft and impermeable to moisture. If desired, these functions may also already have been incorporated in the production of the insert itself.
The outlet openings, viewed in a horizontal direction, are preferably entirely provided next to this passage opening in order to prevent moisture from falling directly through the outlet openings into the passage opening.
Still more preferably, the insert comprises a drip edge under every outlet opening for allowing liquids which enter the air-distributing element via the outlet opening to trickle down next to the passage opening in the base.
Furthermore, the insert preferably comprises a curved guiding surface at the location of the passage opening to guide air from the passage opening to a neighbouring outlet opening.
Several of said outlet openings are preferably arranged around the passage opening in order to distribute the air in an optimum manner. The insert then preferably comprises a conical guide piece at the location of the passage opening in order to guide air from the passage opening to these outlet openings.
In a particular embodiment, the top of this conical guide piece can engage in the passage opening without making contact with the base.
The part of such a conical guide piece adjacent to a surrounding outlet opening may form part of a said curved guiding surface for this surrounding outlet opening. From the top of such a conical guide piece towards a surrounding outlet opening, this guiding surface is then preferably of a convex design for the first part in order to deflect air from the passage opening, and thereafter of a concave design in order to form said drip edge.
Preferably, the base and the insert are furthermore formed in such a way that the bottom side of the insert does not make any contact with the base at the location of the outlet openings, the drip edge and the conical guide piece.
As a result thereof, an optimum distribution of the air is achieved in the direction from the passage opening to the outlet openings.
In order to optimize the air flow, an orthopaedic cushion according to the present invention is furthermore provided with one or more rigid air-guiding elements.
Preferably, said base is then configured as a said rigid air-guiding element. By making this base rigid, it can also be fitted in the aperture so as to be more readily removable. In order to design this base as a rigid air-guiding element, it may be made, for example, from polypropylene (PP), for example by means of injection-moulding.
More specifically, the orthopaedic cushion may comprise a said rigid air-guiding element which delimits the air duct adjoining the outlet of the ventilator. Such a rigid air-guiding element may be made, for example, from acrylonitrile butadiene styrene (ABS), for example by means of injection-moulding.
In addition to said air duct, an orthopaedic cushion according to the present invention may in principle also comprise one or more additional air ducts. Furthermore, one or more outlet openings may also be provided for each air duct. However, in terms of production engineering and to improve the cleanability of the orthopaedic cushion, preferably only one air duct is provided with one associated outlet opening.
Such air ducts may be formed, for example, from pre-shaped tubes which are coupled to the foam block. Such tubes may then be, for example, PVC tubes. If desired, the entire ventilation system may thus be constructed from rigid air-guiding elements. To this end, ducts may then optionally be milled into the foam block in which these tubes are accommodated. In this case, these tubes may be, for example, adhesively fixed.
However, for production reasons and aesthetic reasons, said air duct is preferably incorporated in the foam block.
To this end, the foam block may more specifically comprise:

a base block, in which the holding cavity is provided and in which a perforation is provided at the bottom of the holding cavity;
an inserted block in which a slot is provided;

In this case, said inserted block may be made, for example, from polyurethane (PU) moulded foam or from cold foam. Such an inserted block can easily be provided with a said slot, for example when making the inserted block itself from foam or by means of milling. Using such a base block and such an inserted block, it is then also easy to produce a desired air duct.
Alternatively, but less easily, the air duct could also be provided in the base block itself or a slot for forming the air duct in the base block could be provided, which is delimited with the aid of an insert in order to form the air duct.
The perforation in the base block can easily be drilled out or milled out. This perforation is preferably provided in such a way that an abovementioned aperture is formed when fitting the inserted block under the base block in order to provide a said air-distributing element.
In addition to the base block and the inserted block, the foam block preferably also comprises one or more filler blocks. A said inserted block may then be produced in a standard way with fixed dimensions, whereas the base block can be tailor-made for a patient. If desired, the inserted block may be sawn to length in order to adjust the length of the air duct, if required. The space under the base block and next to the inserted block can then easily be further filled by means of filler blocks.
In addition to the base block and the inserted block and any filler blocks, the foam block furthermore preferably also comprises a ventilator block which is provided with a fitting space, in which the ventilator is fitted, which is provided with a structural component for fastening the ventilator and which is provided with a duct piece adjoining the outlet of the ventilator, wherein this ventilator block is fitted against the base block and the inserted block, so that the duct piece adjoins the slot in order to form the air duct.
Alternatively, the ventilator may also be incorporable in the base block and/or be provided in the inserted block. To this end, this base block and/or this inserted block may then be provided with a structural component.
If the orthopaedic cushion is provided with one or more of said rigid air-guiding elements, the base block and/or the inserted block and/or the filler blocks and/or the ventilator block may then be provided with the necessary apertures in order to accommodate these rigid air-guiding elements therein.
The various possible blocks from which a foam block of an orthopaedic cushion according to the present invention is composed, are preferably attached to each other by gluing.
The present invention will now be explained in more detail by means of the following detailed description of an orthopaedic cushion according to the present invention. The sole aim of this description is to give illustrative examples and to indicate further advantages and particulars of the present invention, and may therefore by no means be interpreted as a limitation of the area of application of the invention or of the patent rights defined in the claims.
Reference numerals are used in this detailed description to refer to the attached drawings, in which:

Fig. 1 shows a total night orthosis according to the present invention in perspective, viewed from the top side;
Fig. 2 shows the night orthosis from Fig. 1 in perspective, viewed from the top side and cut in the longitudinal direction;
Fig. 3 shows the night orthosis from Fig. 1 in perspective, viewed from the top side and in cut-away view;
Fig. 4 shows a part of the night orthosis from Fig. 1 at the location of its air-distributing element in more detail in longitudinal section;
Fig. 5 shows a part of the night orthosis from Fig. 1 at the location of its ventilator in more detail in longitudinal section;
Fig. 6 shows the insert of the air-distributing element of the night orthosis from Fig. 1 separately in perspective, viewed from the top side;
Fig. 7 shows the insert of the air-distributing element of the night orthosis from Fig. 1 separately in perspective, viewed from the bottom side;
Fig. 8 shows the base of the air-distributing element of the night orthosis from Fig. 1 separately in perspective, viewed from the top side.

The illustrated orthopaedic cushion (1) is a back-lying orthosis which is configured as a total night orthosis.
Stomach-lying orthoses, side-lying orthoses, abduction cushions, sitting orthoses, relaxation orthoses, etc. may also be configured in a similar manner.
As can be seen in Fig. 3, this night orthosis (1) comprises a moulded foam block (2) which is composed of a base block (32), an inserted block (21), filler blocks (22) and a ventilator block (23).
The base block (32) is made of PE and is milled to size to fit a patient, similar to known shaped foam blocks. In this way, the base block (32) is provided with a holding cavity (3) in order to position and support the upper body of this patient.
At the bottom of the holding cavity (3), a perforation (8) is milled out, so that a cylindrical opening is created through the base block (32). Here, this perforation (8) is not provided at the lowest point of the holding cavity (3) in order to reduce the load on the system by urine to a minimum. If the aperture (8) is provided at the lowest point of the holding cavity (3), a few extra centimetres of foam material are preferably provided under this lowest point of the holding cavity (3). This serves to ensure that the insert (17) described below and the dish-shaped base (13) described below do not protrude at the location of the base block (32) and that the load on the system by urine is limited to a minimum.
In the illustrated embodiment, this perforation (8) is provided in a virtually flat zone of the holding cavity (3) at the location of the back of the patient. With this night orthosis (1), this is the zone in which the body part of the patient which has the largest surface area is held. In this case, this back is not only supported from underneath, but is also delimited by closely adjoining flanks (37) of the holding cavity (3). If this back is enclosed in this way in this holding cavity (3) when supporting and positioning the patient, this back is highly susceptible to sweating. The base block (32) is furthermore provided with a coating to render this base block (32) smooth, soft and impermeable to moisture.
The inserted block (21) is arranged at the bottom of the base block (32), centrally over the perforation (8) and up to an edge of the base block (32). This inserted block (21) is provided with a slot (28) which faces the base block (32), so that this slot (28) is delimited by the base block (32) in order to form an air duct (6). The slot (28) ends in the perforation (8) so as to form an outlet opening (7) for the air duct (6). In this case, the perforation (8) is also delimited by the inserted block (21) in order to form an aperture (8) at the bottom of the holding cavity (3).
This inserted block (21) is pre-shaped in high-quality PU and has standard dimensions and is cut to length in order to adapt its dimensions to the base block (32). The space under the base block (32) and next to the inserted block (21) is filled with filler blocks (22). These filler blocks (22) may be made of PE, just like the base block (32), and may, for example, be cut from underneath the initially shaped base block (32), in which case a zone is cut out to receive the inserted block (21).
At the head end of the unit comprising the base block (32), the inserted block (21) and the filler blocks (22), the ventilator block (23) is provided. Alternatively, this ventilator block (23) may also be arranged on any desired other side of the base block (32), in which case the positioning of the further modules is adjusted accordingly.
This ventilator block (23) is provided with a fitting space (34) in which a ventilator (4) is arranged.
Adjacent to the outlet (5) of the ventilator (4), an aperture is provided in the ventilator block (32) so as to form a duct piece (36). This duct piece (36) adjoins the slot (28) so as to form the air duct (6). This is shown in more detail in Fig. 5.
The ventilator block (23) is also pre-shaped in high-quality PU and has standard dimensions and is furthermore cut to length in order to adapt its dimensions to the unit comprising the base block (32), the inserted block (21) and the filler blocks (22). The ventilator block (23) is provided with a wooden frame as a structural component (35) in order to secure the ventilator (4).
In the illustrated night orthosis (1), a centrifugal ventilator (4) is provided which operates very quietly and has a long service life.
The ventilator (4) is covered with a cover grille (24) which prevents fingers or small objects from being able to get to the ventilator (4). This cover grille (24) may be made, for example, from ABS, for example via injection-moulding. In the illustrated embodiment, this cover grille (24) is screwed onto the wooden frame (35).
By means of the ventilator (4), air can be sucked in and can be blown to the outlet opening (7) at the bottom of the aperture (8) via the outlet of the ventilator (4) through the shaped air duct (6).
The inserted block (21) and the ventilator block (23) are furthermore provided with an aperture for accommodating a rigid air-guiding element (20) therein, which delimits the air duct (6) adjoining the outlet (5) of the ventilator (4) in order to guide the air in the air duct (6).
This rigid air-guiding element (20) may be made from ABS, for example by injection-moulding.
The base block (32), the inserted block (21), the ventilator block (23) and the filler blocks (22) are attached to each other by gluing.
In the aperture (8) at the bottom of the holding cavity (3), an air-distributing element (11) is arranged in order to distribute the air from the air duct (6) across several outlet openings (12).
This air-distributing element (11) comprises a dish-shaped base (13) which is arranged at the bottom of the aperture (8) and an insert (17) which is arranged at the top of the dish-shaped base (13) and delimits the outlet openings (12).
The insert (17) is detachably provided in the dish-shaped base (13) so as to be able to clean it more easily.
The air-distributing element (11) is provided in the aperture (8) so as to be also removable in its entirety in order to render the unit maintenance-friendly.
In addition, it is also possible first to remove the insert (17) and then to remove the base (13).
In order to make the air-distributing element (11) and the parts (13, 17) thereof easily removable, the dish-shaped base (13) and the insert (17) are provided with corresponding apertures (25, 26) to form handles together for lifting the air-distributing element (11) (or parts thereof) out of the aperture (8). In order to quickly visually recognize the position of the handles, the insert (17) is provided with a corresponding slight recess (29) at the location of these handles.
The dish-shaped base (13) which is shown separately in more detail in Fig. 8 is delimited by a first upright edge (14) at its periphery and comprises a passage opening (16) which is delimited by a second upright edge (15).
The passage opening (16) is connected to the outlet opening (7).
The dish-shaped base (13) is constructed symmetrically with respect to the axis (A) of this passage opening (16).
This dish-shaped base (13) is of rigid construction, for example made of PP by means of, for example, injection-moulding.
This dish-shaped base (13) forms a collecting tray for moisture in order to limit the ingress of moisture into the air duct (6).
The dish-shaped base (13) and the insert (17) together ensure a good air distribution of air from the outlet opening (7) to the outlet openings (12).
The insert (17) is made as a thermoformed part, for example from closed-cell PE foam. Due to the manufacturing technique, this insert (17) is smooth, soft and impermeable to moisture.
The insert (17) is also constructed symmetrically with respect to the axis (A) of the passage opening (16) of the dish-shaped base (13).
This insert (17) is shown separately in more detail in Figs. 6 and 7.
The outlet openings (12) are evenly distributed around the axis (A) in order to distribute the air in an optimum manner.
As can be seen in Fig. 4, the outlet openings (12), viewed in a horizontal direction, are entirely provided next to this passage opening (16) in order to prevent moisture from falling directly through the outlet openings (12) into the passage opening (16).
At the bottom, at the location of the passage opening (16), the insert (17) comprises a conical guide piece (19). The top of this conical guide piece (19) engages in the passage opening (16) without making contact with the dish-shaped base (13). From the top of the conical guide piece (19), the insert (17) comprises a curved guiding surface (33) for each outlet opening (12) in order to guide air from the passage opening (16) to this outlet opening (12). This guiding surface (33) is of a convex structure for the first part from the top of the conical guide piece (19) in order to deflect the air in an optimum manner so as to distribute it in the dish-shaped base (13). In this case, the air is distributed in a star-shaped aperture (31) at the bottom of the insert (17) in order to ensure an optimum distribution of the air across the outlet openings (12). Following the convexly designed part of the guiding surface (33), each guiding surface (33) directed towards the corresponding outlet opening (12) is of a concave design in order to form a drip edge (18) in order to allow liquids which enter the air-distributing element (11) via the outlet openings (12) to drip down into the dish-shaped base (13) next to the passage opening (16).
As can be seen in Figs. 1-3, a three-dimensional fabric (9) is fitted over the air-distributing element (11) in the holding cavity (3), in a zone at the location of the back of the patient, at the bottom of the holding cavity (3), over the flanks (37) of this holding cavity (3) and up to the lateral sides (10) of the holding cavity (3).
In the illustrated night orthosis (1), three-dimensional fabric (9) is fitted which is commercially available under the brand name Aerosleep.
As is indicated by the arrows in Fig. 2, air which is sucked up by the ventilator (4) to blow across the back of a patient, flows through the passage opening (16) via the air duct (6) and hits the bottom side of the conical guide piece (16). This air is distributed proportionally over the star-shaped aperture (31) by means of the conical guide piece (16), away from the axis (A) of the passage opening (16) towards the outer side of the air-distributing element (11). This results in an optimum, virtually laminar air stream.
The air which is distributed to its maximum extent is blown into the three-dimensional fabric (9) via the distributed outlet openings (12). By means of this three-dimensional fabric (9), the air flows in a uniform manner across the back of the patient and is removed via the flanks (37) of the holding cavity (3) along the lateral sides (10) of the holding cavity (3). By means of the three-dimensional fabric (9), some of the air is also distributed over the rest of the holding cavity (3), where the body of the patient is less enclosed and the air is able to leave the holding cavity (3) more easily. Along with the air, excess heat of the patient is also distributed in a uniform way and removed, so that the patient feels more comfortable as a result thereof.
It is furthermore possible to fit a cover made of towelling (not shown) over the illustrated night orthosis (1). Such a cover is permeable to air and does not pose any restrictions with regard to airflow. This cover is made in such a way that it cannot come into contact with the ventilator (4) or electrical parts thereof at the location of the ventilator (4).

Claims

Orthopaedic cushion (1), comprising a shaped foam block (2) which is provided with a holding cavity (3) for holding a body part in order to position and support this body part, characterized in that the orthopaedic cushion (1) is provided with:
- a ventilator (4) for sucking in air and expelling this air via an outlet (5);

- an air duct (6) for the passage of air from the outlet (5) of the ventilator (4) and expelling this air via an outlet opening (7) at the bottom of the holding cavity (3);

- a three-dimensional fabric (9) which is fitted over the outlet opening (7) in the holding cavity (3) and up to lateral sides (10) of the holding cavity (3) for diffusing air and discharging this air via these lateral sides (10).
Orthopaedic cushion (1) according to Claim 1, characterized in that the outlet opening (7) is provided in an aperture (8) at the bottom of the holding cavity (3), and in that the orthopaedic cushion (1) is provided with an air-distributing element (11) which is provided in the aperture (8) for distributing air from the air duct (6) across several outlet openings (12), and in that the three-dimensional fabric (9) is fitted over these outlet openings (12) in order to diffuse the air from these outlet openings (12).
Orthopaedic cushion (1) according to Claim 2, characterized in that the air-distributing element (11) is provided in the aperture (8) so as to be removable.
Orthopaedic cushion (1) according to Claim 3, characterized in that the air-distributing element (11) comprises:
- a base (13) which is arranged at the bottom in the aperture (8) and comprises a bottom (38) which is delimited at the periphery of the bottom (38) by a first upright edge (14) and which comprises a passage opening (16) in the bottom (38), wherein this passage opening (16) is delimited by a second upright edge (15) of the base (13) and is connected to the outlet opening (7); and

- an insert (17) which is detachably arranged at the top of the base (13) and which delimits said outlet openings (12).
Orthopaedic cushion (1) according to Claim 4, characterized in that the insert (17) is made of foam material.
Orthopaedic cushion (1) according to Claim 4 or 5, characterized in that the outlet openings (12), viewed in a horizontal direction, are entirely provided next to this passage opening (16).
Orthopaedic cushion (1) according to Claim 6, characterized in that the insert (17) comprises a drip edge (18) under every outlet opening (12) for allowing liquids which enter the air-distributing element (11) via the outlet opening (12) to trickle down next to the passage opening (16) in the base (13).
Orthopaedic cushion (1) according to one of Claims 4 to 7, characterized in that the insert (17) in the air-distributing element (11) comprises a curved guiding surface (33) at the location of the passage opening (16) to guide air from the passage opening (16) to a neighbouring outlet opening (12).
Orthopaedic cushion (1) according to one of Claims 4 to 8, characterized in that several outlet openings (12) are arranged around the passage opening (16), and in that the insert (17) in the air-distributing element (11) comprises a conical guide piece (19) at the location of the passage opening (16) in order to guide air from the passage opening (16) to these outlet openings (12).
Orthopaedic cushion (1) according to one of the preceding claims, characterized in that the orthopaedic cushion (1) is provided with one or more rigid air-guiding elements (13, 20).
Orthopaedic cushion (1) according to one of Claims 4 to 9 and Claim 10, characterized in that the base (13) is configured as a said rigid air-guiding element (13).
Orthopaedic cushion (1) according to Claim 10 or 11, characterized in that the orthopaedic cushion (1) comprises a said rigid air-guiding element (20) which delimits the air duct (6) adjoining the outlet (5) of the ventilator (4).
Orthopaedic cushion (1) according to one of the preceding claims, characterized in that the air duct (6) is incorporated in the foam block (2).
Orthopaedic cushion (1) according to Claim 13, characterized in that the foam block (2) comprises:
- a base block (32), in which the holding cavity (3) is provided and in which a perforation (8) is provided at the bottom of the holding cavity (3);

- an inserted block (21) in which a slot (28) is provided;
wherein the inserted block (21) is arranged at the bottom of the base block (32), over the perforation (8), and so that the slot (28) is delimited by the base block (32) in order to form the air duct (6) and ends in the perforation (8) in order to form the outlet opening (7).
Orthopaedic cushion (1) according to Claim 14, characterized in that the foam block (2) comprises a ventilator block (23) which is provided with a fitting space (34), in which the ventilator (4) is fitted, is provided with a structural component (35) for fastening the ventilator (4) and is provided with a duct piece (36) adjoining the outlet (5) of the ventilator (4), wherein this ventilator block (23) is fitted against the base block (32) and the inserted block (21), so that the duct piece (36) adjoins the slot (28) in order to form the air duct (6).