Abstract
A kit of replaceable dermatome blade units includes a first dermatome blade unit and a second dermatome blade unit, each dermatome blade unit comprising a blade support having connecting means for releasably attaching the dermatome blade unit to a handle and/or a dermatome head, and a dermatome blade movably attached to the blade support. For each dermatome blade unit a distance in a first direction normal to a main surface of the dermatome blade between the dermatome blade and the connecting means is defined as an attachment height. The attachment height of the first dermatome blade unit is larger than the attachment height of the second dermatome blade unit. A dermatome with such a blade unit, and a kit of parts of a dermatome with two replaceable dermatome heads.
Claims
1. A kit of replaceable dermatome blade units, comprising at least a first dermatome blade unit and a second dermatome blade unit, wherein each dermatome blade unit comprises: a blade support, comprising connecting means for releasably attaching the dermatome blade unit to a handle and/or a dermatome head; and a dermatome blade attached, movably, to the blade support, wherein for each dermatome blade unit a distance in a first direction normal to a main surface of the dermatome blade between the dermatome blade and the connecting means is defined as an attachment height, and wherein the attachment height of the first dermatome blade unit is larger than the attachment height of the second dermatome blade unit.
2. The kit of claim 1, wherein the blade support comprises a cover and a clamping element, the blade being interposed between the cover and the clamping element.
3. The kit of claim 2, wherein a thickness of the cover and/or the clamping element varies from the first to the second dermatome blade unit to provide a corresponding difference in attachment height.
4. The kit of claim 3, wherein a total thickness of the cover and the clamping element and the dermatome blade of each dermatome blade unit is defined in the first direction, and wherein the total thickness of the first dermatome blade unit is equal to the total thickness of the second dermatome blade unit.
5. The kit of claim 2, wherein one of the cover and the clamping element comprises male connecting units and the other of the cover and the clamping element comprises corresponding female connecting units, the male and female connecting units configured to engage each other in order to lock the clamping element in place with respect to the cover.
6. The kit of claim 1, wherein the dermatome blade of each dermatome blade unit is moveable with respect to the respective blade support in a direction substantially parallel to a direction in which a cutting edge of the dermatome blade extends.
7. The kit of claim 1, wherein each dermatome blade comprises an engagement surface configured for engagement by drive means of a dermatome for moving the dermatome blade with respect to the blade support.
8. The kit of claim 7, wherein the engagement surface is formed by an aperture and/or a recess in the dermatome blade.
9. The kit of claim 1, wherein each blade support comprises a guide surface for guiding the dermatome blade unit across skin during use of the respective dermatome blade unit in a dermatome.
10. The kit of claim 1, wherein each dermatome blade unit comprises a removable blade protector removably fixed to the blade support.
11. A dermatome blade unit of claim 1.
12. A dermatome comprising: a handle; a dermatome head attached to the handle, the dermatome head comprising a guide surface for guiding the dermatome head across skin in use of the dermatome; and the dermatome blade unit of claim 11, wherein the dermatome blade unit is attached releasably to the dermatome head using the connecting means of the dermatome blade unit and corresponding connecting means of the dermatome head.
13. The dermatome of claim 12, wherein the connecting means of the dermatome head are stationary with respect to the guide surface of the dermatome head.
14. The dermatome of claim 12, wherein the dermatome head is releasably attached to the handle.
15. The dermatome of claim 12, wherein the handle is provided with a drive mechanism for driving a dermatome blade of a dermatome blade unit attached to the dermatome head in a direction transversal to a grafting direction of the dermatome.
16. The dermatome of claim 12, wherein the handle comprises at least one battery.
17. The dermatome of claim 15, wherein the handle comprises at least one battery, and wherein the drive mechanism is powered by the at least one battery.
18. A kit of parts of the dermatome according to 12, and a further dermatome head, the further dermatome head being releasably attachable to the handle in order to replace the dermatome head, wherein a width of the dermatome head as defined in the direction substantially transversal to the grafting direction is larger than a width of the further dermatome head as defined in the direction transversal to the grafting direction.
19. An assembly of a dermatome head comprising a guide surface for guiding the dermatome head across skin in use of the dermatome, and a dermatome blade unit comprising: a blade support including connecting means for releasably attaching the dermatome blade unit to a handle and/or the dermatome head; and a dermatome blade attached to the blade support, wherein a distance in a first direction normal to a main surface of the dermatome blade between the dermatome blade and the connecting means is defined as an attachment height, and wherein the attachment height of the first dermatome blade unit is larger than the attachment height of a second dermatome blade unit.
20. The kit of claim 10, wherein the removable blade protector is removably fixed to the blade support via a breakable connector.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0067] The invention will be further elucidated with reference to the attached drawings, in which:
[0068] FIGS. 1A and 1B respectively show schematically a perspective view and a blow up view of a dermatome;
[0069] FIGS. 2A and 2B schematically show cross sections of two different dermatome blade units;
[0070] FIGS. 3A and 3B respectively show schematically a perspective view and a blow up view of a dermatome blade unit;
[0071] FIGS. 4A and 4B respectively show schematically a perspective view and a blow up view of a dermatome blade unit with a blade protector; and
[0072] FIG. 5 schematically shows a dermatome blade unit with a blade protector.
DETAILED DESCRIPTION
[0073] Throughout the figures, like elements will be referred to using like reference numerals. Like elements across different embodiments will be referred to using reference numerals increased by 100 (one hundred).
[0074] FIGS. 1A and 1B show a dermatome 1 which comprises a handle 2 and a head 3. The dermatome 1 defines a grafting direction G and a width direction W transversal thereto. The handle 2 is provided with a set of resilient hooks 4 which can be retracted by pressing a button 5 associated with the hooks 4. The hooks extend from the handle 2 of the dermatome 1 for engaging the head 3. The head 3 has corresponding apertures (not visible) in which the hooks 4 engage when the head 3 is connected to the handle 2. Accordingly, the head 3 can be removed from and fixed to the handle 2 by suitable operation of the hooks 4. Accordingly, different heads 3 with similar apertures may be attached to the same handle 2. In particular, heads 3 of different widths b may be used as desired. FIG. 1B partially shows drive means 23, which comprise an arm 24 which is pivotable about a joint 25 and in rotation about the joint 25 by an eccentrically mounted cam 26. The arm 24 comprises at its end a pin 27 of a relatively hard material, such as a hardened metal, for engagement of the dermatome blade 9 described below. FIG. 1B also shows a dermatome blade unit 6 which in its entirety can be connected to and released from the dermatome head 3. For this purpose, the dermatome blade unit 6 is provided with connection means 7-1, 7-2 (collectively referred to as 7). The head 3 is provided with corresponding connecting means 8. Further details of the dermatome blade unit 6 will be described below with reference to the following figures.
[0075] FIGS. 2A and 2B each show a dermatome blade unit 106, 206 which could be used in the dermatome 1 of FIGS. 1A-1B. the dermatome blade unit 106, 206 has a dermatome blade 109, 209 and a blade support, which herein consists of a cover 110, 210 and a clamping element 111, 211, although other components could also be part of the blade support. The dermatome blade 109, 209 has a main body 112, 212 and a cutting edge 113, 213. The main body 112, 212 defines a main plane 114, 214 and a direction N normal thereto. The cover 110, 210 comprises connecting means 107-1, 207-1 and 107-2, 207-2, which are schematically represented in FIGS. 2A and 2B. Taking one of the connecting means 107-1, 207-1 as a reference, an attachment height h.sub.1, h.sub.2 for the dermatome blade 109, 209 can be defined. The attachment height h.sub.1, h.sub.2 defines the position of the dermatome blade 109, 209 with respect to the head 3 once the dermatome blade unit 106, 206 has been connected to the head 3. Comparing the dermatome blade unit 106 of FIG. 2A to that 206 of FIG. 2B, the attachment heights h.sub.1, h.sub.2 are different. The difference is caused by varying a thickness t.sub.1, t.sub.2 of the cover 110, 210, so that the dermatome blade 109, 209 is held at the desired attachment height h.sub.1, h.sub.2 with respect to the connecting means 107-1, 207-1. The clamping element 111, 211 has a thickness d.sub.1, d.sub.2 which is varied in correspondence with the thickness t.sub.1, t.sub.2 of the cover 110, 210, so that a total thickness t.sub.t of the dermatome blade unit 106, 206 remains constant even when the attachment height h.sub.1, h.sub.2 is varied. The thicknesses t.sub.1, t.sub.2, t.sub.t, d.sub.1, d.sub.2 and the attachment height h.sub.1, h.sub.2 are defined in the normal direction N.
[0076] FIGS. 3A and 3B show the dermatome blade unit 6 of FIGS. 1A and 1B in more detail. In particular, it can be seen that both types connecting means 7-1, 7-2 comprise hooks 7-1, 7-2 which extend towards opposites sides from the cover 10. Accordingly, the cover 10 can be suspended between cooperating connecting means 8 in the head 3 from the connecting means 7. The connecting means 7 are made from a slightly resilient material, in this example plastic, so that they can deform and snap into place for locking the cover 10 in place in the head 3. The front of the connecting means 7-1 functions at the same time as a guide surface 15 for guiding the dermatome blade unit 6 across the skin in use of the dermatome 1. The cover 10 is provided with a series of pillars 16 which extend in the normal direction N. Each pillar 16 is provided with a stop 17, in this example embodied as a wider bottom part of the pillar 16 near the main body of the cover 10. The clamping element 11 is provided with corresponding apertures 18, in which the pillars 16 can be pressed with some force. The pillars 16 and apertures 18 are shaped such that a clamping action keeps the clamping element 11 in place with respect to the cover 10. The dermatome blade 9 is arranged between the cover 10 and the clamping element 11. The dermatome blade 9 comprises slots 19 which correspond to the pillars 16 of the cover 10. The slots 19 are somewhat wider than the diameter of the pillars 16, so that the dermatome blade 9 can slide in the width direction W width respect to the cover 10 and the clamping element 11. In motion of the blade 9 with respect to the cover 10, the slots 20 move in their longitudinal direction while the pillars 16 remain stationary and in the slots 20. As such, the pillars 16 thus move along the length of their respective slots 20, as seen from the reference point of the pillars 16. The blade 9 further includes an aperture 21, 22, which has an engagement part 21 which is relatively narrow, and a wider receiving part 22. The inside surface of the engagement part 21 forms an engagement surface for engagement by a drive means 23 of the dermatome 1. The receiving part 22 allows, due to its larger dimensions, easy insertion of the drive means 23, in particular the pin 27 thereof, into the aperture 21, 22. The pin 27 can then, during placing of dermatome blade unit 6 in the head 3, be moved to the engagement part 21, where it engages the surface of the engagement part 21 for moving the dermatome blade 9 in the width direction reciprocally with respect to the blade support and with respect to the head 3 and handle 2. The cover 10 and the clamping element 11 comprise oversized apertures 28, 29 which align with the apertures 21, 22 of the dermatome blade 9. The oversized apertures allow the pin 27 of the drive means 23 to engage only the dermatome blade 9. The dermatome blade unit 6 is further provided with a marking 30 which indicates the dimensions of the dermatome blade unit 6. In particular, an indication representative of the attachment height h.sub.1, h.sub.2, or the thickness of a skin graft cut with such an attachment height h.sub.1, h.sub.2, may be displayed, so as to allow easily distinguishing different dermatome blade units 6.
[0077] FIGS. 4A and 4B show different perspective views of a dermatome blade unit 306 which is the same as the above-described dermatome blade unit 6, but differs in that it is provided with a blade protector 331, which is removably fixed to the blade support. The blade protector 331 covers the dermatome blade 309 to protect it from inadvertent contact. The blade protector 331 comprises a tab 332 which can be pulled in order to remove the blade protector 331 from the dermatome blade unit 306. The blade protector 331 is fixed by engaging with protrusions (not shown) in apertures 333 in the cover 310.
[0078] FIG. 5 shows a similar dermatome blade unit 406, which differs only in that the blade protector 431 is removably fixed to the cover 410 using a breakable connection along the length of the blade protector 431. It is thus connected along a line 434 to the cover 410. The connection line 434 is made from a relatively thin part of material, in this case plastic, so that it may be broken to remove the blade protector 431, for instance tilting the blade protector 431 with respect to the cover 310, e.g., by pulling at the tab 432.
[0079] Although the invention has been described above with reference to specific embodiments and examples, the invention is not limited thereto. Instead, the invention is also defined by the following claims.
