WO2023031637A1

WO2023031637A1 - Interchangeable sole for high heel shoes

Info

Publication number: WO2023031637A1
Application number: PCT/IB2021/000593
Authority: WO
Inventors: Lena OBERSON; Jules REVAIS; Marc SOUPLY
Original assignee: Chabloz Orthopédie
Priority date: 2021-09-01
Filing date: 2021-09-01
Publication date: 2023-03-09

Abstract

The present invention concerns a prosthetic foot cover comprising a core part configured for surrounding a prosthetic foot and an external sole part. The external sole part extends between a toe end and a heel end of the prosthetic foot cover and can be detached from the core part. The invention also concerns a procedure for manufacturing a prosthetic foot cover.

Description

INTERCHANGEABLE SOLE FOR HIGH HEEL SHOES SPECIFICATION

TECHNICAL FIELD AND PRIOR ART

Prosthetic feet may be covered by prosthetic foot covers in order to provide a natural appearance. Further, prosthetic foot covers may improve the functionality of prosthetic feet, for example by providing adapted damping properties and by protecting the foot prosthesis.

Prosthetic foot covers may further be customized for a use with different types of shoes. However, mounting and detaching the prosthetic foot cover from the foot prosthesis is difficult, as the prosthetic foot cover needs to be firmly attached to the foot prosthesis. Also, a complete prosthetic foot cover is voluminous and heavy to transport, making it difficult for a user to have different foot covers available when travelling.

The present invention therefore provides a prosthetic foot cover which can be easily adapted to different uses.

SUMMARY OF THE INVENTION

In the following, a prosthetic foot cover is presented. The prosthetic foot cover comprises:

- a core part configured for surrounding a prosthetic foot and

- an external sole part, wherein the external sole part extends between a toe end and a heel end of the prosthetic foot cover and wherein the external sole part can be detached from the core part.

Advantageously, the prosthetic foot cover further comprises a phalangeal part being sized to replace the toes of a foot, the phalangeal part being detachable from the core part, preferably the phalangeal part forming a single piece of continuous material with the sole part, preferably the phalangeal part comprising a slot for receiving a tip of a foot blade of a prosthetic foot.

The external sole part may have a thickness and an external curvature such that a gap is filled, said gap arising between an internal sole line of a flat shoe and an internal sole line of a shoe with a heel, preferably a heel height of the heel (160) being above 2 cm or above 3 cm.

A thickness of the sole part may be greater between the toe end and a metatarsophalangeal (MTP) joint position than at a heel position.

Further, a first sole part situated between the toe end and an MTP joint position may have an inclination angle with respect to a straight line extending between the heel position and the MTP position, wherein the inclination angle is equal to or more than 10 degrees, advantageously equal to or more than 20 degrees.

A second sole part situated between the MTP joint position and the heel may present an upward curvature.

Advantageously, the phalangeal part has a pointed toe shape representing toes oriented towards a midline of the foot.

Also, the external sole part may be attached to the core part by a hook and loop connection and/or by a magnetic force connection.

The external sole part may be attached to the core part at the heel end by a snap-fit connection.

A prosthetic foot cover set may comprise a prosthetic foot cover as described beforehand and further comprising an additional external sole part configured for use with the core part, the additional external sole part being different from the external sole part with respect to

- the inclination angle of the first sole part and/or

- the curvature of the second sole part and/or - a stiffness and/or a damping property and/or a water resistance and/or holes for water drainage and/or a color and/or a surface finishing.

A prosthetic foot may comprise a prosthetic foot cover as described beforehand and a foot prosthesis with a foot blade, preferably the foot prosthesis comprising an adjustable ankle.

Further presented is a procedure for manufacturing a prosthetic foot cover as described beforehand, the procedure comprising the steps of

- providing the core part of the prosthetic foot cover,

- providing a model of a shoe,

- determining a shape of the external sole part of the prosthetic foot cover by comparing said model of the shoe and said core part,

- manufacturing the external sole part, preferably using a 3D printing method, wherein preferably providing the model of the shoe includes scanning the sole of the shoe.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 shows a prosthetic foot comprising a foot blade with a tip of the foot blade.

Figure 2 shows a prosthetic foot covered by a prosthetic foot cover.

Figure 3 shows the prosthetic foot with a core part without an external sole part.

Figure 4 shows the external sole part detached from the core part.

Figure 5 shows a further example of the prosthetic foot cover.

Figure 6 shows the core part configured for use with the external sole part and the phalangeal part.

Figure 7 shows a further perspective of the core part configured for use with the external sole part and the phalangeal part.

Figure 8 shows the external sole part with the phalangeal part detached from the core part. Figure 9 shows shoes with different heel types and heel heights and an adaptation of the external sole part to the shoe type.

Figure 10 shows the prosthetic foot cover with the core part and the external sole part.

Figure 11 shows the prosthetic foot cover with an external sole part and a detachable phalangeal part.

Figure 12 shows a procedure for manufacturing a prosthetic foot cover.

DETAILED DESCRIPTION OF PARTICULAR EMBODIMENTS

Figure 1 shows a prosthetic foot (20) comprising a foot blade (290) with a tip (100) of the foot blade. The prosthetic foot may comprise an adjustable ankle (300).

An adjustable ankle allows to manually or automatically change the ankle angle. The ankle angle is the angle between the prosthetic foot and the shin part of the prosthesis. The adjustable ankle thereby allows to adjust the prosthesis to different shoe heel heights. If the ankle angle would not be adjusted when the shoe heel height is increased, then a knee angle would need to change, thereby leading to instabilities of the leg. The prosthetic foot cover presented in the following may advantageously be used with a foot prosthesis comprising an adjustable ankle so that the overall heel height can change. Alternatively, a foot prosthesis without an adjustable ankle may be used. In this case, an ankle angle may be changed using the screws of a pyramid adapter of the foot prosthesis.

Figure 2 shows the prosthetic foot (20) covered by a prosthetic foot cover (10). The prosthetic foot cover comprises a core part (30) which is configured to surround the prosthetic foot. The prosthetic foot cover further comprises an external sole part (40). The external sole part extends between a toe end (50) and a heel end (60) of the prosthetic foot cover (10).

The core part is designed to tightly surround the corresponding prosthetic foot. A particular core part is therefore adapted to fit around specific prosthetic foot type. The core part may be configured to be endurable when in use with the specific prosthesis. The core part may also be designed to provide a natural look. The fitting between the core part and the prosthetic foot is as is generally known for a fitting between a prosthetic foot cover and a prosthetic foot. Often, the prosthetic foot covers known in the art can only be removed by a technician due to the strong and tight fitting requirements.

The detachable external sole part is a relatively small part compared to the core part. The external sole part is therefore easy and non-expensive to manufacture. The sole part can be configured to fulfill primarily functional requirements as providing a damping behavior, a grip behavior or a roll-over behavior. Requirements of a durability and natural look may be secondary to the functional requirements.

Figure 2 further shows a metatarsophalangeal (MTP) joint position (170). The metatarsophalangeal joints (MTP joints) are the joints between the metatarsal bones of the foot and the proximal bones or proximal phalanges of the toes. As the prosthetic foot cover is similar to a form of a foot, an MTP joint position can be indicated on the prosthetic cover. The MTP joint is the point where the natural foot bends in when performing a flexion of the toes, for example when the heel is lifted off the ground (plantarflexion). A first sole part (190) extends between the toe end and the MTP joint position. A second sole part (220) is situated between the MTP joint position and the heel end. A thickness of the sole part (110) is indicated by a double flash in figure 2 and the following figures. As will be further described below, the external sole part can be detached from the core part. The external sole part, as a separate part, has a thickness (110). Said thickness may vary between the toe end and the heel end. For example, the thickness may be different at the MTP joint position and at a heel position (180). The external sole part further has an external side which is the side being in contact with the ground when the prosthetic foot cover is in use. Said external side may present an external curvature (120) deviating from a straight line, as shown for example in figure 2. Said straight line may for example be comprised by the ground surface, when the prosthetic foot cover with the external sole part is posed flat on the ground.

Figures 3 shows the prosthetic foot (20) with the core part (30) without the external sole part. In the configuration shown, the external sole part has been detached from the core part. Figure 4 shows the external sole part detached from the core part.

The core part is configured for surrounding the prosthetic foot. The core part therefore covers a part of an upper side and of a lower side of the foot blade. The core part may also completely cover the upper and the lower side of the foot blade. In both cases, the core part may also cover other parts of the foot prosthesis. The core part is firmly attached to the foot prosthesis by means known in the art for attaching a cosmesis to a foot prosthesis. For example, the core part may be attached using screws. As the attachment needs to very tight, these screws need to be fastened with high strength. The screws may therefore be difficult to loosen for a user, for example an elderly person or a patient with further disabilities.

The external sole part (40) is a separate part from the core part and provides a complete external side which is in contact with the ground when the prosthetic foot cover is in use. As stated beforehand, the external sole part can be attached and detached or removed from the core part. Linking means (260) may be provided on the core part and/or on the external sole part for providing a connection force. For example, a hook and loop and/or magnetic force and/or Velcro strap, and/or removable glue connection can be provided.

Preferably, the external sole part and the core part are provided with a form configured for carrying transverse forces in use. For example, the external sole part may be provided with a rim (370) surrounding the sole part on an upper surface, contacting the core part, as shown in figure 4. The core part may be provided with a socket (380) on a lower surface, contacting the external sole part on its upper surface. When the external sole part is mounted on the core part, the rim contacts the socket. Transverse forces, exerted for example on the external sole part, can be transmitted to the core part via the contact of the surrounding rim and the socket.

Figure 5 shows a further example of the prosthetic foot cover. Same features as introduced beforehand are designated by the same reference signs. Figure 5 shows a phalangeal part (70) which is configured to replace the toes of a foot (80). The phalangeal part approximately extends between a toe end and the MTP joint position of the prosthetic foot cover, similarly to the toes of a natural foot, which are formed by the proximal phalanges attached by the MTP joint to the metatarsal bones. The phalangeal part can be detached from the core part. Preferably, the phalangeal part is made as a single piece together with the external sole part. In this case, the phalangeal part forms a single piece of continuous material with the sole part and can be detached together with the sole part from the core part.

The phalangeal part may comprise a slot (90) which is configured for receiving the tip of the foot blade of the prosthetic foot. In this case, the attachment of the external sole comprising the phalangeal part to the core part is improved and more stable, as the phalangeal part may be carried by the tip of the foot blade.

Figure 6 shows the core part configured for use with the external sole part and the phalangeal part. The external sole part and the phalangeal part have been detached. The core part surrounds the prosthetic foot and thereby covers the upper and lower side of the foot blade (290) with the exception of the tip (100) of the foot blade. The tip of the foot blade can comprise a length of several centimeters, for example 1, 2 or 3 centimeters. The core part remains firmly attached to the prosthetic foot while the external sole part can be easily detached from the core part. The core part may also be removed from the prosthetic foot, however, the core part and the prosthetic foot are in a firm connection allowing transmission of forces in several directions. The core part surrounds the prosthetic foot making removal more complicated than the removal of the sole part which only needs to be detached from the core part. The core part is in tight fit and form closure with the prosthetic foot and the prosthetic foot blade.

Figure 7 shows a further perspective of the core part configured for use with the external sole part and the phalangeal part, already shown in figure 6. The external sole part and the phalangeal part have been detached from the core part.

Figure 8 shows the external sole part with the phalangeal part detached from the core part.

Figures 7 and 8 show a snap-fit connection (270) for attaching the external sole part to the core part at the heel end. The snap fit connection may be situated at the heel end of the prosthetic foot cover. Advantageously, the snap-fit connection is used with an external sole forming a single piece of material with the phalangeal part, where the phalangeal part comprises the slot (90) for receiving the tip (100) of the foot blade. In this case, the external sole with the phalangeal part can be easily held between the tip of the food blade and the snap-fit connector (270) situated at the heel end.

A prosthetic foot cover comprising a core part and a detachable external sole part has the advantage that a worn or defective external sole part may be replaced with a new external sole part without needing to replace the complete prosthetic foot cover. As the external sole part is in contact with the ground during use, the external sole part will become used before the core part. Only replacing the external sole part therefore presents a cost advantage.

A prosthetic foot cover comprising a core part and a detachable external sole part further allows an easy way to adapt a prosthetic foot cover to a particular kind of shoe, as will be described in the following. An adaptation of the prosthetic foot cover to the shoe type may be provided by an adaptation of the sole part alone while keeping the same core part. Therefore, providing a prosthetic foot cover for a given type of shoe amounts to providing the core part and further providing an external sole part which is adapted to the particular kind of shoe.

Figures 9A to 9M show shoes with different heel types and heel heights and an adaptation of the external sole part to the respective shoe type. A flat walking ground (320) is indicated by a line.

Figures 9A shows a shoe with a flat sole. Figures 9D, 9G and 9J show a shoe with a heel (150). A heel (160) may have different heel heights. For example, a heel height may be 0,5 cm, 1 cm, 3 cm, 5 cm or 7 cm. Figures 9A, 9D, 9G and 9J further show an internal sole line (140). The internal sole line is the form of the shoe sole on the inside of the shoe. The internal sole line is in contact with the external sole part when the prosthesis with the prosthetic foot cover is worn with the respective shoe, presenting the respective internal sole line.

Figures 9B, 9E, 9H and 9K show the internal sole line (140) of the respective shoe shown in figures 9A, 9D, 9G and 9J. The internal sole line is shown positioned flat on the ground i.e. without the heel. The internal sole line of the flat shoe shown in figure 9A is mostly flat, with only a small inclination or rounded portion close to the toe end, corresponding to a form of the toes. Said small inclination typically has an angle equal to or below 5 degrees with the ground when the flat shoe rests on flat ground.

The internal sole line of a shoe with a heel presents a first part, situated between a toe end and a position corresponding to the MTP joint position, which is inclined upwards. Further, the internal sole line presents a second part situated between said MTP joint position and the heel end which has an upward curvature. With an increase in shoe heel height, as shown between figure 9D and 9G or 9G and 9J, said inclination of the first part and said upward curvature of the second part become stronger, as can be seen comparing figures 9E, 9H and 9K.

Figures 9B, 9E, 9H and 9K also show a prosthetic foot cover with the core part and the external sole part. The external sole part shown in these images is adapted to a shoe without a heel or flat shoe, as is shown in figure 9A. As can be seen in figures 9B and 9C this external sole part closely follows the internal sole line of the flat shoe of figure 9A. The prosthetic foot cover may therefore be comfortly worn with the flat sole shoe of figure 9A.

Figures 9E, 9H and 9K however show that said external sole part does not follow the internal sole line (140) of a shoe with a heel. A gap (130) arises between said external sole part for a flat shoe and the internal sole line of the shoes with a heel. Said gap corresponds in size and form to the difference between an internal sole line of a flat shoe and an internal sole line of a shoe with a heel. In other words, the gap (130) arises between an internal sole line (140) of a flat shoe and an internal sole line (140) of a shoe (150) with a heel. Said gap also corresponds in size and form to the gap which would arise between the core part and the internal sole line of the respective shoe with a heel. Consequently, the thickness and the external curvature of the sole part need to be adapted in order to fill said gap, such that the prosthetic foot cover fits the shoe.

Figures 9F, 91, 9L and 9M show the prosthetic foot cover with an external sole part with a thickness and an external curvature (120) such that said gap is filled. As has been pointed out beforehand, only the external sole part is adapted in thickness and external curvature. Consequently, the same core part can be used with different external sole parts, as shown in figures 9C, 9F, 91 and 9L, to provide a prosthetic foot cover adapted to the different shoes of figures 9A, 9D, 9G and 9J. As can be seen in figures 9F, 91, 9L and 9M, the external sole with adapted thickness and external curvature closely follows the internal sole line of the respective shoe. Therefore, the prosthetic foot cover can be comfortly worn with the respective shoe.

Advantageously, the prosthetic foot cover can be provided as a set, comprising a core part and several sole parts. Different shoes provide different general properties, to which the prosthetic foot cover can be adapted by adapting the external sole part. For example, the prosthetic foot with the cover can be adapted to provide the same properties in different shoes. Further, the prosthetic foot with the cover can be adapted to different uses like walking, running or jumping.

A prosthetic foot cover set may comprise a prosthetic foot cover as described beforehand and further an additional external sole part configured for use with the core part. The additional external sole part can be different from the external sole part. For example, the additional external sole part can comprise a different inclination angle of the first sole part and/or a different curvature of the second sole part. In this case, the prosthetic foot cover set can be easily used with different shoes of different heel sizes. A user can easily adapt his prosthetic cover to the shoe he or she would like to wear by choosing an adapted external sole from the different external soles provided in the set. Further, an external sole may comprise a different stiffness and/or damping property. The prosthetic foot cover can thereby be adapted to walking on different grounds, running, shoe damping properties or barefoot walking. Also, a further external sole may provide a water resistance and/or holes for water drainage and/or a color and/or a different surface finishing to be adapted to a use intended by the wearer of the prosthesis with the prosthetic cover.

Figure 10 further illustrates how a thickness and an external curvature of the external sole is provided such that said gap is filled in order to adapt the prosthetic foot cover with the external sole part to the shoe. In all figures, a thickness of the sole part (110) at different positions is indicated by a double arrow at the respective position. Figures 10A, 10B, IOC and 10D show the prosthetic foot cover with the core part and the external sole part. Figures 10C and 10D further show the phalangeal part forming a single piece of continuous material with the external sole part. In the following, modifications of the thickness and external curvature of the external sole part are described which allow adapting the prosthetic foot cover to a shoe with a heel.

Figure 10A shows the prosthetic foot cover with the external sole part, where the external sole part is adapted for a shoe with a flat internal sole line, as shown in figure 9A. The thickness of the external sole part (110) is greater at the heel position (180) than between the toe end (50) and the MTP joint position (170). When standing in a flat shoe, most of the user weight is carried by the heel. Therefore, the external sole part may be provided with a greater thickness at the heel position than towards the toe end.

Figure 10B shows the prosthetic foot cover with an external sole where a thickness of the sole part is greater between the toe end and the MTP joint position than at the heel position. The prosthetic foot cover is thereby adapted for a use with a shoe with a heel. The prosthetic foot cover of figure 10B is shown in a position as if placed in said shoe with a heel, without showing the shoe. A corresponding shoe with a heel and internal sole line of the shoe are shown in figure 9J and in figure 9M.

As can be seen in figure 10B, the thickness of the external sole part (110) between the MTP joint position (170) and the toe end (50) is thicker than at the heel position (180). When the prosthetic foot cover is placed within the shoe with a heel, more of the user's weight is carried by the sole part situated towards the toe end than by the sole part situated towards the heel position. It is therefore advantageous to provide a greater thickness of the external sole part between the MTP joint position and the toe end. Further, it can be seen that the second sole part (220), situated between the MTP joint position and the heel, presents an upward curvature (230). The external sole part is thereby adapted to follow the curvature of the internal sole line of a shoe with a heel, as shown in figure 9M.

Figure 10B further shows that the first sole part (190) situated between the toe end and the MTP joint position has an inclination angle (200) with respect to a straight line (210) extending between the heel end and the MTP joint position. The straight line (210) may correspond to a line drawn between an outside surface of the sole at the heel position and the MTP joint articulation. The straight line (210) may also correspond to the ground surface when the prosthetic foot cover is placed flat on the ground without a shoe, as shown in figures 10A, 10C. The first sole part, situated between the toe end and the MTP joint position, can be a partly flat surface situated between the toe end and the MTP joint position. Said first sole part with said inclination angle advantageously provides a standing surface towards the toe end when the prosthetic foot cover is placed within a shoe with a heel. A value of the inclination angle (200) may be equal to or larger than 10°, advantageously equal to or larger than 20°. Advantageously, an angle of 10° is used for a shoe with a heel height between 1 cm and 3 cm. An angle of 20° is advantageously used for a heel height between 4 cm to 6 cm. As can be seen in figures 9M and 10B, the inclined first sole part lies flat on the internal sole part of the shoe and no gap is present between the internal sole line of the shoe and the prosthetic foot cover. The increased thickness of the external sole part between the toe end and the MTP joint position advantageously allows to form the first sole part with the inclination angle on the external sole part.

Figures 10C and 10D show the prosthetic foot cover comprising the phalangeal part (70) which forms a single piece of continuous material with the sole part.

Figure 10C shows the prosthetic foot cover with the external sole part, where the external sole part is adapted for a shoe with a flat internal sole line, as shown in figure 9A.

Figure 10D shows the prosthetic foot cover with an external sole part adapted for a use with a shoe with a heel, for example as shown in figure 9J. The first sole part (190), situated between the toe end and the MTP joint position, has an inclination angle with respect to a straight line extending between the heel and the MTP joint position. In the example shown in figure 10D, said straight line corresponds to the ground surface when the prosthetic foot cover is placed flat on the ground without a shoe, as shown in figure 10C. In the example shown in figure 10D, the inclination angle of the first sole part can be provided by inclining the phalangeal part. Advantageously, the phalangeal part may be inclined around an axis defined by the MTP joints of a natural foot. The phalangeal part thereby simulates the toes of a natural foot in dorsiflexion. As can be seen in figure 10D and figure 9L, the external sole part with the inclined phalangeal part closely follows the internal sole line of a shoe with a heel. The prosthetic foot cover may therefore be comfortly worn with a high heeled shoe. Figure 10D further shows that the second sole part (220) presents an upward curvature (230). The external sole part is thereby adapted to follow the curvature of the internal sole line of a shoe with a heel, as also shown in figure 9L.

Figure 11A and figure 11B show the prosthetic foot cover with an external sole part and a detachable phalangeal part. The phalangeal part is situated between the toe end (50) and the MTP joint position (170) and is provided with toes (80). Figures 11A and 11B also show a midline of the foot (250) which is also a midline of the prosthetic foot cover.

Figure 11A shows the toes (80) of the phalangeal part oriented mostly parallel to the midline (250) of the foot. This orientation of the toes mostly corresponds to a natural and unconstrained toe position. The prosthetic foot cover is thereby adapted to a shoe with a wide shoe tip.

Figure 11B shows the toes of the phalangeal part oriented towards the midline of the foot. The toes are inclined towards the midline and the phalangeal part presents a pointed shape. The prosthetic foot cover is thereby adapted to a shoe with a narrow tip or a shoe tip presenting a triangular shape or a pointed shoe tip.

Figure 12 shows a procedure for manufacturing a prosthetic foot cover as described beforehand. In particular, a method for manufacturing the external sole part is described.

In a first step (330), the core part of the prosthetic foot cover is provided.

In a second step (340), a model of a shoe is provided. For example, the model of the shoe can be provided by a shoe manufacturer or a shoe can be scanned to obtain said model. The model can include the entire shoe or be limited to the shoe sole. Preferably, the sole of the shoe is scanned. In a third step (350) a shape of the external sole part of the prosthetic foot cover is determined by comparing said model of the shoe and said core part. In particular, a thickness and an external curvature of the external sole part are determined such that a gap between the core part and the internal sole line of the shoe is filled. In a fourth step (360) the external sole part is manufactured, preferably by a 3D printing method.

Claims

1. Prosthetic foot cover (10) comprising:

- a core part (30) configured for surrounding a prosthetic foot (20) and

- an external sole (40) part wherein the external sole part extends between a toe end (50) and a heel end (60) of the prosthetic foot cover and wherein the external sole part can be detached from the core part.

2. Prosthetic foot cover according to claim 1 further comprising a phalangeal part (70) being sized to replace the toes (80) of a foot, the phalangeal part being detachable from the core part, preferably the phalangeal part forming a single piece of continuous material with the sole part, preferably the phalangeal part comprising a slot (90) for receiving a tip (100) of a foot blade of a prosthetic foot.

3. Prosthetic foot cover according to claim 1 or 2 wherein the external sole part has a thickness (110) and an external curvature (120) such that a gap (130) is filled, said gap (130) arising between an internal sole line (140) of a flat shoe and an internal sole line (140) of a shoe (150) with a heel, preferably a heel height of the heel (160) being above 2 cm or above 3 cm.

4. Prosthetic foot cover according to claim 1 or 3 wherein a thickness (110) of the sole part is greater between the toe end and a metatarsophalangeal (MTP) joint position (170) than at a heel position (180).

5. Prosthetic foot cover according to any of the preceding claims wherein a first sole part (190) situated between the toe end and an MTP joint position has an inclination angle (200) with respect to a straight line (210) extending between the heel position and the MTP position, wherein the inclination angle is equal to or more than 10 degrees, advantageously equal to or more than 20 degrees.

6. Prosthetic foot cover according to any of the preceding claims wherein a second sole part (220) situated between the MTP joint position and the heel presents an upward curvature (230).

7. Prosthetic foot cover according to any of the preceding claims and claim 2 wherein the phalangeal part has a pointed toe shape (240) representing toes oriented towards a midline (250) of the foot.

8. Prosthetic foot cover according to any of the preceding claims wherein the external sole part is attached to the core part by a hook and loop connection and/or by a magnetic force connection (260).

9. Prosthetic foot cover according to any of the preceding claims and claim 2 wherein the external sole part is attached to the core part at the heel end by a snap-fit connection (270).

10. Prosthetic foot cover set comprising a prosthetic foot cover according to any of the preceding claims and further comprising an additional external sole part configured for use with the core part, the additional (280) external sole part being different from the external sole part with respect to 17

- the inclination angle of the first sole part and/or

- the curvature of the second sole part and/or

- a stiffness and/or a damping property and/or a water resistance and/or holes for water drainage and/or a color and/or a surface finishing.

11. Prosthetic foot (20) comprising a prosthetic foot cover according to any of the preceding claims and a foot prosthesis with a foot blade (290), preferably the foot prosthesis comprising an adjustable ankle (300).

12. Procedure for manufacturing a prosthetic foot cover according to any of claims 1 to 8 comprising the steps of:

- providing the core part of the prosthetic foot cover,

- providing a model of a shoe,