Abstract
A method for producing an immobilisation element for immobilising a body part of a patient on a supporting surface, wherein the immobilisation element includes a sheet of thermoplastic material for receiving the body part to be immobilised, and at least one profile for fixing the immobilisation element to the supporting surface, wherein the profile includes a first fixing means for fixing the profile to the sheet, wherein the fixing means includes a groove that receives the sheet so that the first and the second contact surfaces lie along the sheet, and wherein at least one of the first contact surface and the second contact surface is provided with at least one protrusion that penetrates the sheet in order to anchor the sheet.
Claims
1. A method for producing an immobilisation element for immobilising a body part of a patient on a supporting surface, the method comprising: providing a sheet of thermoplastic material for receiving the body part; providing a profile which on a first side comprises a first fixing means for fixing the profile to the sheet, and on a second side different from the first side comprises a second fixing means for releasably fixing the profile to the supporting surface, wherein the first fixing means comprises a groove delimited by a first contact surface and a second contact surface opposite the first contact surface for receiving the sheet of thermoplastic material; placing the sheet of thermoplastic material in the groove of the first fixing means so that the first and the second contact surfaces lie along the sheet; and creating at least one protrusion in at least one of the first contact surface or the second contact surface so that the at least one protrusion penetrates the sheet of thermoplastic material in order to anchor the sheet of thermoplastic material in the groove.
2. The method for producing the immobilisation element according to claim 1, wherein providing the profile is performed after providing the sheet of thermoplastic material, wherein placing the sheet of thermoplastic material in the groove of the first fixing means is performed after providing the profile, and wherein creating the at least one protrusion is performed after placing the sheet of thermoplastic material in the groove of the first fixing means.
3. The method for producing the immobilisation element according to claim 1, wherein creating at least one protrusion in at least one of the first contact surface or the second contact surface comprises compressing a die and the profile so that the profile is plastically deformed into the first and second contact surfaces provided with the at least one protrusion.
4. The method for producing the immobilisation element according to claim 3, wherein the die is provided with teeth which press the at least one protrusions into the profile.
5. An immobilisation element for immobilising a body part of a patient on a supporting surface, wherein the immobilisation element comprises: a sheet of thermoplastic material for receiving the body part to be immobilised; and at least one profile for fixing the immobilisation element to the supporting surface, wherein a first side of the profile comprises a first fixing means for fixing the profile to the sheet, and a second side of the profile different from the first side comprises a second fixing means for releasably fixing the profile to the supporting surface, wherein the first fixing means comprises a groove delimited by a first contact surface and a second contact surface opposite the first contact surface, wherein the groove receives the sheet so that the first and the second contact surfaces lie along the sheet, wherein at least one of the first contact surface or the second contact surface is provided with at least one protrusion, wherein the at least one protrusion penetrates the sheet of thermoplastic material in a thickness direction of the sheet in order to anchor the sheet of thermoplastic material in the groove.
6. The immobilisation element according to claim 5, wherein the sheet of thermoplastic material is anchored in the groove by clamping the sheet by the at least one protrusion.
7. The immobilisation element according to claim 5, wherein the protrusion partially penetrates the sheet of thermoplastic material in the thickness direction of the sheet.
8. The immobilisation element according to claim 5, wherein at least one of the first contact surface or the second contact surface is provided with a set of protrusions.
9. The immobilisation element according to claim 8, wherein the set of protrusions comprises at least one row of protrusions, wherein focal points of cross-sections of protrusions in the at least one row lie on a same straight line oriented along a longitudinal direction of the groove.
10. The immobilisation element according to claim 9, wherein the set of protrusions comprises a first row of protrusions and at least one following second row of protrusions, wherein the first row of protrusions and the at least one following second row of protrusions run parallel to each other.
11. The immobilisation element according to claim 10, wherein a focal point of a cross-section of each protrusion provided in the at least one row of protrusions is remote by an inter-protrusion distance from a focal point of a neighbouring protrusion in the row of protrusions, wherein inter-protrusion distances of each protrusion in the at least one row are equal.
12. The immobilisation element according to claim 11, wherein the first row of protrusions and the at least one following second row of protrusions have a same inter-protrusion distance and a same offset relative to each other along a longitudinal direction, wherein the offset is smaller than the inter-protrusion distance of the row.
13. The immobilisation element according to claim 5, wherein both the first contact surface and the second contact surface are provided with at least one protrusion.
14-18. (canceled)
19. A method of using an immobilisation element for immobilising a body part of a patient on a supporting surface, wherein the immobilisation element comprises: a sheet of thermoplastic material for receiving the body part to be immobilised; and at least one profile for fixing the immobilisation element to the supporting surface, wherein a first side comprises a first fixing means for fixing the profile to the sheet, and a second side of the profile different from the first side comprises a second fixing means for releasably fixing the profile to the supporting surface, wherein the first fixing means comprises a groove delimited by a first contact surface and a second contact surface opposite the first contact surface, wherein the groove receives the sheet so that the first and the second contact surfaces lie along the sheet, wherein at least one of the first contact surface or the second contact surface is provided with at least one protrusion, wherein the at least one protrusion penetrates the sheet of thermoplastic material in a thickness direction of the sheet in order to anchor the sheet of thermoplastic material in the groove, the method comprising: heating the immobilisation element; drawing the sheet of thermoplastic material over the body part to be immobilised; and retaining the sheet of thermoplastic material to the body part to be immobilised.
20-22. (canceled)
23. A machine for performing a method for producing an immobilisation element for immobilising a body part of a patient on a supporting surface, wherein the method comprises providing a sheet of thermoplastic material for receiving the body part; providing a profile which on a first side comprises a first fixing means for fixing the profile to the sheet, and on a second side different from the first side comprises a second fixing means for releasably fixing the profile to the supporting surface, wherein the first fixing means comprises a groove delimited by a first contact surface and a second contact surface opposite the first contact surface for receiving the sheet of thermoplastic material; placing the sheet of thermoplastic material in the groove of the first fixing means so that the first and the second contact surfaces lie along the sheet; and creating at least one protrusion in at least one of the first contact surface or the second contact surface so that the at least one protrusion penetrates the sheet of thermoplastic material in order to anchor the sheet of thermoplastic material in the groove, the machine comprising: a holding device for receiving the profile and the sheet; a die provided with teeth for pressing at least one protrusion into the profile under the influence of a pressure force; and a pressing device for compressing the profile and the die so that the profile deforms plastically into the first and second contact surface provided with the at least one protrusion.
24. (canceled)
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0056] The invention will be explained in more detail below with reference to the following description and the attached drawings.
[0057] FIG. 1 shows a perspective view of part of the immobilisation element.
[0058] FIG. 2 shows the immobilisation element for immobilising a body part of a patient on a supporting surface.
[0059] FIG. 3 shows the step of the method in which a profile and a sheet are applied.
[0060] FIG. 4 shows the step of placing the sheet of thermoplastic material in the groove of the first fixing means of the profile.
[0061] FIG. 5 shows a step of providing a machine for creating the protrusion in the profile.
[0062] FIG. 6 shows the use of the machine during creation of the protrusion in the profile.
[0063] FIG. 7 shows the immobilisation element after removal of machine for creating the protrusion.
EMBODIMENTS OF THE INVENTION
[0064] The present invention will be described below with reference to clearly defined embodiments and with reference to specific drawings, but the invention is not restricted thereto and is defined solely by the claims. The drawings shown here are merely diagrammatic depictions and are not restrictive. In the drawings, the dimensions of certain components may be shown enlarged, which means that the components in question are not shown to scale, purely for illustrative purposes. The dimensions and relative dimensions do not necessarily correspond to actual practical embodiments of the invention.
[0065] In addition, terms such as first, second, third and similar in the description and in the claims are used to make a distinction between similar elements, and not necessarily to indicate a sequential or chronological order. The terms concerned are mutually interchangeable under appropriate circumstances, and the embodiments of the invention may function in different orders from those described or illustrated here.
[0066] The term comprising and derived terms as used in the claims should not be interpreted as being restricted to the means which are specified thereafter; this term does not exclude other elements or steps. The term should be interpreted as a specification of the indicated properties, numbers, steps or components to which reference is made, without excluding the presence or addition of one or more secondary properties, numbers, steps or components or groups thereof. The scope of an expression such as a device comprising means A and B is then not simply limited to devices which consist solely of components A and B. In contrast, it means that with regard to the present invention, the only relevant components are A and B.
[0067] FIG. 1 shows a perspective view of part of the immobilisation element 1. The immobilisation element 1 comprises a sheet 8 of thermoplastic material and a profile 3. The immobilisation element 1 is intended for immobilising a body part of a patient, such as a patient's head, on a supporting surface 2 as shown in FIG. 2. The sheet 8 is intended for receiving the body part to be immobilised. This is achieved by initially heating the sheet 8, for example in a warm water bath or an oven, or for example by electromagnetic radiation, so that the sheet 8 becomes deformable and can be drawn over the body part to be immobilised. After cooling of the sheet 8, and for example further hardening of the sheet, the sheet 8 is hard and rigid, which allows immobilisation of the body part during the actual treatment. For this, during the actual treatment, the body part to be immobilised is placed on the supporting surface 2, and the immobilisation element 1 is connected by means of the profile 3 to the supporting surface 2 while the already initially deformed sheet 8 is placed over the body part to be immobilised. As shown in FIG. 1, the profile 3 for this comprises on the first side a first fixing means 4 for fixing the profile 3 to the sheet 8, and the profile 3 furthermore comprises, on a second side opposite the first side, a second fixing means 5 for releasably fixing the profile 3 to the supporting surface 2. Since the second fixing means 5 attaches the profile 3 releasably to the supporting surface 2, the immobilisation element 1 may be used for repeated actual treatments of the patient, preferably the same patient. The immobilisation elements 1 as shown in FIGS. 1 and 2 are often used for medical diagnoses and/or radiation therapy, wherein the immobilisation, for example the repeated immobilisation, of the patient's body part during diagnosis or treatment is of crucial importance. The firm and durable fixing of the sheet 8 to the profile 3, for example during repeated treatments, despite the high tensile forces which occur between the sheet 8 and the profile 3 during the initial deformation of the sheet 8 and during the actual use of the immobilisation element 1 in a treatment, is achieved by anchoring the sheet 8 to the profile 3 by means of at least one protrusion 10 which penetrates the sheet 8. The immobilisation element 1 as shown in FIG. 1 is provided with a set of protrusions 10 which penetrate the sheet 8 in order to attach the sheet 8 to the profile 3.
[0068] The method for producing the immobilisation element 1 is discussed further with reference to FIGS. 3 to 7. The method for producing the immobilisation element 1 provides a number of successive steps which may be performed either by the end user of the immobilisation element 1, for example by the nursing personnel before initial deformation of the sheet 8, or by the supplier of the immobilisation element 1 before delivery of the immobilisation element 1 to the end user.
[0069] The method for producing the immobilisation element 1 comprises as a first step the provision of a profile 3 as shown in FIG. 3. The profile which is provided comprises on a first side a first fixing means 4 for fixing the profile 3 to the sheet 8, and on a second side opposite the first side a second fixing means 5 for releasably fixing the profile 3 to the supporting surface 2. The user of the immobilisation element 1 provides a profile 3 which is provided with the correct type of second fixing means 5 corresponding to the supporting surface 2 of the user and the desired fixing of the profile to the supporting surface 2. The first fixing means 4 of the profile 3 comprises a groove 9 delimited by two opposite groove walls 15 which are integrally connected to each other. The groove 9 has an elongate direction parallel to the supporting surface 2, which is referred to as the longitudinal direction of the groove 9, a shorter transverse direction approximately perpendicular to the opposing groove walls 15, and a depth direction perpendicular to the longitudinal direction and the transverse direction of the groove 9. The entire profile 3 is made of one piece, in other words the first fixing means 4 is integrally connected to the second fixing means 5. FIG. 3 also shows the step of providing a sheet 8 of thermoplastic material. The user of the immobilisation element 1 provides a sheet 8 which has the correct properties, such as a suitable sheet size and thickness, a suitable material and a suitable form corresponding to the expected use of the immobilisation element 1. Thus the user for example provides a larger and thicker sheet 8 for an obese person compared with a non-obese person, for immobilising the same body part, since the provision of a sheet 8 which is too small and too thin for an obese person leads to overstretching of the sheet 8 in the initial deformation of the sheet, which increases the risk of failure of the immobilisation element 1. Thus the user for example also provides a sheet 8, the shape of which is adapted to the body part to be immobilised, for example a shape adapted for immobilising the patient's head as shown in FIG. 2. The sheet 8 of thermoplastic material as shown in FIG. 3 is perforated, for example to allow evaporation via the skin, or to allow visual inspection of the skin under the sheet, or to reduce attenuation of the sheet 8 to a minimum. The part of the sheet 8 of thermoplastic material which is intended to be placed in the groove 9 of the profile 3 is not perforated, in order to the reduce the risk of deformation or tearing of the sheet 8 in the groove 9 during use of the immobilisation element 1.
[0070] FIG. 4 shows the step of placing the sheet 8 of thermoplastic material in the groove 9 of the first fixing means 4. FIG. 4 shows the arranged profile 3 in a cross-section perpendicular to the longitudinal direction of the groove 9. The groove 9 of the first fixing means 4 receives the sheet 8 of thermoplastic material. The opposing groove walls 15 respectively describe a first contact surface 6 and a second contact surface 7 opposite the first contact surface 6, as the part of the groove walls 15 which lie along the sheet 8. The sheet 8 has a sheet thickness d1 approximately equal to the width of the groove 9.
[0071] In order to anchor the sheet 8 firmly and durably in the groove 9 of the profile 3, a set of protrusions must be created in the contact surface 6, 7 of the profile 3 such that the protrusions penetrate the sheet 8. FIGS. 5 to 7 show an exemplary embodiment for creating a protrusion. As shown in FIG. 5, a machine is provided for this. The machine comprises a holding device 13, for example a holder, for receiving the profile 3 and the sheet 8. The machine furthermore comprises two dies 11 provided with teeth 12 for pressing the at least one protrusion into the contact surface of the profile 3 under the influence of a pressure force. In FIG. 5, the two dies 11 lie adjacent to the groove walls 15. Alternatively, only one die may be provided, lying adjacent to one of the groove walls, in order to provide protrusions only in one groove wall 15. FIG. 5 furthermore shows only one die 11 with teeth 12, wherein FIG. 5 shows a transverse cross-section of the machine, and the teeth 12 in the machine shown are aligned in the longitudinal direction on the one die 11 relative to the opposite die 11. The machine furthermore comprises a pressing device 14 for compressing the profile 3 and the teeth 12 of the die 11, so that the profile 3 deforms plastically until the first and second contact surfaces 6, 7 are provided with at least one protrusion. In order to press the teeth 12 and the profile 3 together, firstly the teeth 12 are provided movably in the die 11, wherein the pressing device 14 pushes the teeth 12 out of the die 11, or secondly the teeth 12 are connected integrally with the die 11, wherein the pressing device 14 presses the complete die 11 provided with teeth 12 against the profile 3. FIG. 5 shows a die 11 with movable teeth 12. The transverse cross-section shown in FIG. 5 depicts only one tooth 12 in the depth direction of the groove 9. Preferably, the machine comprises a set of teeth 12 which correspond to the pattern of protrusions to be applied, for example by providing several teeth 12 in the depth direction of the groove 9. The holding device 13 is furthermore provided with an adjustment device 18 provided for bringing the dies 11 towards each other or moving them apart. If the dies 11 are brought towards each other, this ensures amongst others that the profile 3 is fixedly held during creation of the protrusion and during retraction of the teeth 12 from the protrusion.
[0072] FIG. 6 shows the use of the machine during creation of the protrusion 10 in the profile 3. More specifically, FIG. 6 shows the teeth 12 of the die 11 which plastically deform the contact surface 6 of the profile 3 in order to form a protrusion 10. The teeth 12 of the die 11 penetrate the sheet 8 maximally. Here the sheet 8 is not perforated but merely partially penetrated. In one embodiment (not illustrated in FIG. 6), the formed protrusion 10 protrudes maximally by a height h1 from the contact surface 6 on which the protrusion is provided, and the height h1 is smaller than the width of the groove, which for example is equal to the thickness d1 of the sheet 8, such that the protrusion cannot bore through the sheet, for example cannot penetrate it completely. Part of the sheet 8 is consequently clamped between the protrusion 10 and the contact surface 7 opposite the contact surface 6 on which the protrusion 10 is provided. The clamped sheet 8 forms a fleece which ensures a firm adhesion of the sheet 8 to the protrusion 10 and the contact surface 7 opposite the contact surface 6 on which the protrusion 10 is provided. It is also possible that on maximal penetration of the teeth 12 into the profile 3, the height h1 is greater than the width of the groove, which for example is equal to the thickness d1 of the sheet 8, as long as the sheet 8 is only partially penetrated in order to form a fleece. This situation is shown in FIG. 6. FIG. 6 furthermore shows that the contact surface 7 opposite the contact surface 6 on which the at least one protrusion 10 is provided, opposite the at least one protrusion 10, is provided with at least one bulge 19, wherein the bulge 19 points away from the sheet 8. More specifically, the bulge 19 is oriented in the same direction as the opposite protrusion 10. The clamp sheet 8 forms a fleece which ensures a firm adhesion of the sheet 8 to the protrusion 10 and the bulge 19.
[0073] FIG. 7 shows the immobilisation element 1 after removal of the machine for creating the protrusion 10. When the teeth 12 of the machine have been removed from the profile 3 and the sheet 8, a hollow protrusion 10 remains. In the example described here, the material properties and dimensions of the groove walls 15 and the sheet 8 of thermoplastic material are selected such that the created protrusion 10 forms a rivet connection. If the protrusion 10 is formed by deep-drawing of a small area of the contact surface 6, a protrusion is created with thin protrusion walls 16 and a relatively thick protrusion head 17. The resulting created protrusion 10 has a relatively hard and rigid protrusion head 17 compared with relatively flexible protrusion walls 16. As shown in FIG. 6, the sheet 8 of thermoplastic material is elastically stretched by penetration of the teeth 12, whereby the sheet 8 tends to spring back resiliently after removal of the teeth 12. Since the protrusion walls 16 are relatively flexible compared with the protrusion head 17, the sheet 8 springs back elastically by compression of the protrusion walls 16, while the protrusion head 17 remains almost unchanged. Here, at least part of the sheet 8 is pinched between the protrusion head 17 and the contact surface 6 on which the protrusion 10 is formed, i.e. a rivet connection is formed. The rivet connection thus formed ensures an optimal anchoring of the sheet 8 in the groove 9 of the profile 3. The anchoring provides a firm and durable connection of the sheet without the need to use external materials to form the rivet connection. In addition, the rivet connection thus formed is almost unaffected by atmospheric influences, since no secondary adhesive substances must be used such as glue.
