Comminution device for minimally invasive comminution of tissue

Abstract

The invention relates to a comminution device for minimally invasive comminution of tissue, comprising: a hollow-cylindrical tube; a cutting tool rotatably received in the region of a distal suction opening of the hollow-cylindrical tube; a handpiece for holding and guiding the comminution device; a drive arranged in the handpiece for generating a rotational movement of the cutting tool; and a coupling for producing a reversible connection between the handpiece and the hollow-cylindrical tube, wherein the coupling has a coupling sleeve arranged on the handpiece and a coupling pin which is arranged on the proximal end of the hollow-cylindrical tube and can be inserted into the coupling sleeve. The object of the invention is that of providing an improved comminution device. For this purpose, the invention proposes that the coupling pin (5) has at least two latching projections (6) which project radially with respect to the longitudinal axis of the hollow-cylindrical tube (1), are spaced apart from one another in the circumferential direction, and engage in corresponding latching recesses (7) of the coupling sleeve (4), as a result of which the hollow-cylindrical tube (1) can be connected to the handpiece (2) only in precisely one position.

Description

[0001] Shredding device for minimally invasive shredding of tissue

[0002] The invention relates to a shredding device for minimally invasive shredding of tissue, comprising a hollow cylindrical tube, a cutting tool rotatably mounted in the region of a distal suction opening of the hollow cylindrical tube, a handpiece for holding and guiding the shredding device, a drive arranged in the handpiece for generating a rotational movement of the cutting tool, and a coupling for establishing a reversible connection between the handpiece and the hollow cylindrical tube, wherein the coupling has a coupling sleeve arranged on the handpiece and a coupling pin arranged at the proximal end of the hollow cylindrical tube, which can be inserted into the coupling sleeve.

[0003] Furthermore, the invention relates to a cutting tool set for such a shredding device.

[0004] Morcellation devices for minimally invasive tissue fragmentation (also known as morcellation devices) are highly specialized medical devices used in various surgical procedures, e.g., prostate enucleation or laparoscopic removal of uterine fibroids.

[0005] A shredding device of the type described above has a hollow cylindrical tube that forms the outer part of the device. The tissue to be shredded is drawn in through the tube (typically using a suction pump connected to the tube) and guided to the cutting tool. The hollow cylindrical tube has a distal intake opening that allows the tissue to be drawn in so that it can be grasped by the cutting tool. The cutting tool is rotatably mounted and supported inside the hollow cylindrical tube. The cutting tool is, for example, a hollow blade that rotates at high speed (>500 rpm) inside the hollow cylindrical tube and shreds the tissue fed in through the intake opening into smaller pieces.

[0006] The device's handpiece serves as a grip and control tool for the surgeon. It is ergonomically designed to ensure comfortable and precise handling during the procedure. The handpiece houses the drive unit, which generates the rotational movement of the cutting tool. This drive unit can be electrically or pneumatically powered, depending on the model and specific design of the device. The drive unit ensures that the cutting tool receives the necessary force and speed to effectively fragment the tissue.

[0007] The connection between the hollow cylindrical tube and the handpiece is made via a coupling. This coupling is designed to allow a reversible connection, meaning that the tube and handpiece can be easily separated and reattached as needed. The coupling consists of a coupling sleeve located on the handpiece and a coupling pin attached to the proximal end of the hollow cylindrical tube. The coupling pin is inserted into the coupling sleeve and locked into place, creating a secure and stable connection.

[0008] In this procedure, the mincing device is inserted through a body opening or a small incision in the patient's body. The hollow cylindrical tube is typically guided to the target site via the working channel of a minimally invasive instrument, where the tissue is aspirated and directed to the cutting tool. The drive in the handpiece rotates the cutting tool, thus mincing the tissue. The small tissue fragments are then removed through the hollow cylindrical tube. The coupling allows the tube to be quickly and easily detached from the handpiece when necessary, for example, for cleaning / sterilization or for replacing the cutting tool. This design enables efficient, safe, and minimally invasive tissue mincing that is gentle on the patient.

[0009] The couplings used in known shredding devices have several disadvantages. For example, the existing solutions for connecting to the handpiece have drawbacks regarding manufacturing effort and – above all – cleaning / sterilization.

[0010] The locking mechanisms of conventional couplings have small, difficult-to-access areas, which can lead to uncertainties regarding sterility. Design solutions that use O-ring seals that are difficult or impossible to access also pose a risk to sterility.

[0011] Another weakness lies in the materials used. While the metal version is resistant to aging and wear, it is significantly heavier. Weight is a crucial factor for minimally invasive instruments. On the other hand, the familiar plastic versions suffer from high wear. The cutting tool rotates at up to 8000 revolutions per minute within the hollow cylindrical tube. This leads to increased abrasion. The result is impaired concentricity, which propagates distally along the tube, which can be up to 400 mm long, and can negatively impact the surgical outcome. This effect is further amplified with repeated use, also due to material aging caused by cleaning and sterilization.

[0012] Further disadvantages arise from the construction of the couplings from several plastic parts, which are usually joined by adhesive or form-fitting connections. The resulting gaps due to the manufacturing process are, in turn, problematic with regard to sterilization.

[0013] Furthermore, connecting the hollow cylindrical tube to the coupling is problematic in known devices. While metal parts can be securely welded or soldered together, the metal cylindrical outer tube must be pressed, glued, or overmolded to the plastic parts of the coupling. These connections are not always precise, are subject to increased wear, and pose uncertainties regarding sterility.

[0014] In practice, when using conventional devices, problems frequently arise when separating the cutting tool set, consisting of the hollow cylindrical tube and the cutting tool, from the handpiece. The resulting one-sided, i.e., asymmetrical, load on the coupling leads to misalignment, jamming, or stiffness of the coupling, which can only be resolved with considerable force. This, in turn, can cause the hollow cylindrical tube to bend, resulting in poor concentricity of the cutting tool.

[0015] One challenge for the device is its leak-tightness. Within the coupling, the coupling pin on the tube must be tightly connected to the coupling sleeve on the handpiece. This is often achieved using O-ring seals. In many known devices, the O-ring seal is located on the inner surface of the handpiece's coupling sleeve. In this position, the O-ring is not visible, difficult to replace, difficult to clean, and subject to increased wear. It's important to consider that the handpiece is reused several hundred times, while the cutting tool set to which it is connected is only used up to approximately ten times.

[0016] Another disadvantage is that, in known devices, the position of the hollow cylindrical tube containing the cutting tool and the suction opening relative to the handpiece is not defined when the handpiece is connected. The suction opening is usually located distally and laterally on the hollow cylindrical tube. This means that the surgeon has to orient themselves regarding the tube's position before each procedure. This can lead to errors during the procedure.

[0017] Against this background, the object of the invention is to provide an improved shredding device that avoids at least some of the aforementioned disadvantages. The invention achieves this object, starting from a shredding device of the type described above, by providing the coupling pin with at least two radially projecting locking projections, spaced apart from each other in the circumferential direction, which engage in corresponding locking recesses in the coupling sleeve, thus ensuring that the hollow cylindrical tube can only be connected to the handpiece in exactly one position.

[0018] The two or more locking lugs facilitate the separation of the hollow cylindrical tube from the handpiece using the cutting tool. The two locking lugs can be gripped with two fingers (thumb and forefinger) of one hand, preventing uneven pressure when pulling out the coupling pin. This also prevents tilting. Furthermore, the locking lugs, in combination with the corresponding locking recesses in the coupling sleeve, reliably ensure that the hollow cylindrical tube can only be connected to the handpiece in one specific position. This makes the shredding device particularly user-friendly.

[0019] In the context of the shredding device described here, distal means "away from the handpiece", i.e., the side facing the patient to be treated, while proximal means "towards the handpiece", i.e., the side of the device facing away from the patient.

[0020] In one possible embodiment, a drive shaft connected to the cutting tool is provided, extending through the hollow cylindrical tube to its proximal end. This corresponds to the usual design. The drive shaft connects the drive to the cutting tool along the length of the hollow cylindrical tube, transmitting torque to set the cutting tool in rotation. Advantageously, the coupling pin is manufactured as an injection-molded plastic part with a metallic bearing element overmolded by the plastic. This bearing element is designed to rotatably support the drive shaft within the coupling pin. The composite plastic and metal part combines the advantages of low weight with the benefits of low-wear, stable, and reliable bearing operation. The bearing within the metallic bearing element ensures smooth and vibration-free operation over the long term. The bearing arrangement is advantageously implemented as a sliding bearing.To avoid seizing, the material pairing of the drive shaft and the bearing part can be appropriately selected.

[0021] In another possible embodiment, a drive pin is provided within the coupling sleeve and is driven by the drive in a rotating manner. Correspondingly, a positive or frictional locking element is provided at the proximal end of the drive shaft to create a torque-transmitting positive or frictional connection between the drive shaft and the drive pin when the coupling pin is inserted into the coupling sleeve. To establish the torque-transmitting connection from the drive via the drive shaft to the cutting tool, only the coupling pin needs to be inserted into the coupling sleeve. The positive or frictional locking element can have a cylindrical section on the outer surface of which an O-ring is rotatably attached to a cylindrical inner surface of the coupling pin. Due to the O-ring's position on the outer surface, it is visible and easily accessible when the tube is disconnected from the handpiece.The condition of the worn O-ring can therefore be easily assessed. If necessary, the O-ring can be easily replaced.

[0022] Advantageously, the locking projections on the coupling pin are arranged opposite each other with respect to the longitudinal axis of the hollow cylindrical tube, i.e., symmetrically. This effectively prevents one-sided force application when connecting or disconnecting the coupling pin and coupling sleeve. To ensure that the hollow cylindrical tube can only be connected to the handpiece in exactly one position, the locking projections can be of different dimensions and engage in corresponding locking recesses of different dimensions in the coupling sleeve. For example, the locking projections can be designed as locking wings of different thicknesses that engage in corresponding slot-shaped locking recesses of different widths in the coupling sleeve.In one possible embodiment, the coupling pin has a sealing element on its outer surface, in particular an O-ring, which, when the coupling pin is inserted into the coupling sleeve, seals against an inner surface of the coupling sleeve. In this embodiment, the O-ring, which is subject to wear, is located on the part of the shredding device that is replaced more frequently, namely on the coupling pin connected to the hollow cylindrical tube. The O-ring, located on the outer surface, is clearly visible and accessible, so that it can be easily replaced if damaged.

[0023] The invention also relates to a cutting tool set for a shredding device of the type described above. The cutting tool set refers to the part of the shredding device described above that can be reversibly connected to the handpiece. The cutting tool set comprises a hollow cylindrical tube, a cutting tool rotatably mounted in the region of a distal intake opening of the hollow cylindrical tube, and a coupling pin arranged at a proximal end of the hollow cylindrical tube, designed and intended for insertion into a coupling sleeve arranged on a handpiece of the shredding device. The handpiece with coupling sleeve is not part of the cutting tool set.As explained above, the coupling pin has at least two radially projecting locking projections, spaced apart from each other in the circumferential direction, relative to the longitudinal axis of the hollow cylindrical tube. These projections are designed and intended to engage corresponding locking recesses in the coupling sleeve, ensuring that the hollow cylindrical tube can only be connected to the handpiece in exactly one position. Advantageously, the coupling pin with the locking projections is formed monolithically, for example, as an injection-molded plastic part with the overmolded metallic bearing component for rotatable mounting of the drive shaft within the coupling pin, as described above.

[0024] An embodiment of the invention is explained in more detail below with reference to the drawings. They show: Fig. 1A, B, C: Views of the comminution device according to the invention with handpiece and the associated hollow cylindrical tube;

[0025] Fig. 2A,B,C: Views of the proximal end of the hollow cylindrical tube with coupling pin;

[0026] Fig. 3: View of the coupling pin as

[0027] Composite part made of plastic with a metallic bearing part.

[0028] The illustrated morcellation device (also known as a morcellation device) is used for the minimally invasive fragmentation of tissue. It comprises a hollow cylindrical tube 1, of which only a proximal section is shown in the drawings. In the region of a distal suction opening (not shown), a cutting tool (also not shown) is rotatably mounted in the hollow cylindrical tube 1. A handpiece 2 serves to hold and guide the morcellation device. A drive unit (not shown), e.g., an electric motor, is housed in the handpiece 2 to generate a rotational movement of the cutting tool. A [missing information] in Fig.1 The coupling, designated as 3 in its entirety, serves to create a reversible connection between handpiece 2 and hollow cylindrical tube 1, wherein the coupling 3 has a coupling sleeve 4 arranged on the handpiece and a coupling pin 5 arranged at the proximal end of the hollow cylindrical tube 1, which can be inserted into the coupling sleeve 4.

[0029] The coupling pin 5 has at least two locking projections 6 in the form of locking wings, which extend radially from the longitudinal axis of the hollow cylindrical tube 1, are spaced apart from each other circumferentially, and are symmetrically opposed with respect to the longitudinal axis of the tube 1. The locking wings 7 have sections 6', 6" of different thicknesses (see Fig. 3) which engage in corresponding, differently wide, slot-shaped locking recesses 7 of the coupling sleeve 4, whereby the hollow cylindrical tube 1 can only be connected to the handpiece 2 in exactly one position. A drive shaft (not shown) extends through the tube 1, which serves to transmit the drive force from the drive to the cutting tool in order to set it in rotation. Fig.Figure 2 shows that a positive locking element 8 with cross-shaped slots on the end face is arranged at the proximal end of the drive shaft, which serves to create a drive connection between the drive shaft and a drive pin (not shown) on the handpiece 2 corresponding to the positive locking element 8 when the coupling pin 5 is inserted into the coupling sleeve 4.

[0030] Fig. 3 illustrates that the coupling pin 5 is manufactured as an injection-molded plastic part, with a metallic bearing element 9 (shown separately on the left) overmolded by the plastic for rotatably mounting the drive shaft in the coupling pin 5. The bearing element 9 protrudes from the coupling pin 5 on the left, i.e., on the side facing the hollow cylindrical tube 1, thus forming a projection for connection to the hollow cylindrical tube 1 (e.g., by welding). The coupling pin 5 is monolithically formed with the locking wings 6. It can be seen that the locking wings 6 can be elastically pressed inwards to release the positive locking between the coupling pin 5 and the coupling sleeve 4 by means of locking hooks 11 of the coupling pin 4 engaging in the coupling sleeve 4.

[0031] Figures 2 and 3 show a circumferential groove 10 on the coupling pin 5. This groove serves to receive an O-ring (not shown), which, when the coupling pin 5 is inserted into the coupling sleeve 4, seals against an inner surface of the coupling sleeve 4.

Claims

Patent claims 1. Shredding device for minimally invasive shredding of tissue, comprising a hollow cylindrical tube (1), a cutting tool rotatably mounted in the region of a distal suction opening of the hollow cylindrical tube (1), and a handpiece (2) for holding and guiding the A shredding device comprising a drive arranged in the handpiece (2) for generating a rotational movement of the cutting tool, a coupling (3) for establishing a reversible connection between the handpiece (2) and the hollow cylindrical tube (1), wherein the coupling (3) has a coupling sleeve (4) arranged on the handpiece (2) and a coupling pin (5) arranged at the proximal end of the hollow cylindrical tube (1) and insertable into the coupling sleeve (4), characterized in that the coupling pin (5) has at least two radially projecting, circumferentially spaced locking projections (6) with respect to the longitudinal axis of the hollow cylindrical tube (1), which engage in corresponding locking recesses (7) of the coupling sleeve (4), whereby the hollow cylindrical tube (1) can only be connected to the handpiece (2) in exactly one position.

2. Comminution device according to claim 1, comprising a drive shaft connected to the cutting tool, which extends through the hollow cylindrical tube (1) to its proximal end.

3. Comminution device according to claim 2, wherein the coupling pin (5) is manufactured as an injection-molded plastic part, with a metallic bearing part (9) overmolded by the plastic, provided and designed for rotatable bearing of the drive shaft in the coupling pin (5).

4. Crushing device according to one of claims 1 to 3, with a drive pin received in the coupling sleeve (5) and driven by the drive in a rotating manner.

5. Crushing device according to claim 4, comprising a form-fit or friction-fit element (8) arranged at the proximal end of the drive shaft, designed and configured to produce a torque-transmitting form-fit or friction-fit connection between the drive shaft and the drive pin when the coupling pin (5) is inserted into the coupling sleeve (4).

6. Comminution device according to claim 5, wherein the form-fit or friction-fit element (8) has a cylindrical section on the outer surface of which an O-sealing ring rotatably abuts a cylindrical inner surface of the coupling pin (5).

7. Crushing device according to one of claims 1 to 6, wherein the locking projections (6) on the coupling pin (5) are arranged opposite each other with respect to the longitudinal axis of the hollow cylindrical tube (1).

8. Crushing device according to one of claims 1 to 7, wherein the locking projections (6) are dimensioned differently and engage in corresponding locking recesses (7) of the coupling sleeve (4) of correspondingly different dimensions.

9. Comminution device according to claim 8, wherein the locking projections (6) are designed as locking wings of different thicknesses, which are arranged in corresponding slot-shaped locking recesses (7) of different widths in the coupling sleeve (4) engage.

10. Crushing device according to one of claims 1 to 9, wherein the coupling pin (5) has a sealing element, in particular an O-ring, on its outer surface which, when the coupling pin (5) is inserted into the coupling sleeve (4), bears in a sealing position against an inner surface of the coupling sleeve (4).

11. Cutting tool set for a shredding device according to one of claims 1 to 10, comprising a hollow cylindrical tube (1), a cutting tool rotatably mounted in the region of a distal intake opening of the hollow cylindrical tube (1), a coupling pin (5) arranged at a proximal end of the hollow cylindrical tube (1), designed and intended for insertion into a coupling sleeve (4) arranged on a handpiece (2) of the shredding device, characterized in that the coupling pin (5) has at least two radially projecting locking projections (6) spaced apart from each other in the circumferential direction with respect to the longitudinal axis of the hollow cylindrical tube (1), which are designed and intended to engage in corresponding locking recesses (7) of the coupling sleeve (4), whereby the hollow cylindrical tube (1) can only be connected to the handpiece (2) in exactly one position.

12. Cutting tool set according to claim 11, comprising a drive shaft connected to the cutting tool, which extends through the hollow cylindrical tube (1) to its proximal end.

13. Cutting tool set according to claim 12, wherein the coupling pin (5) is manufactured as an injection-molded plastic part, with a metallic bearing part (9) overmolded by the plastic, provided and designed for rotatable bearing of the drive shaft in the coupling pin (5).

14. Cutting tool set according to claim 13, comprising a form-fit or friction-fit element (8) arranged at the proximal end of the drive shaft, designed and configured to produce a torque-transmitting form-fit or friction-fit connection between the drive shaft and a drive pin of the handpiece (2) when the coupling pin (5) is inserted into the coupling sleeve (4).

15. Cutting tool set according to claim 14, wherein the form or friction locking element (8) has a cylindrical section, on the outer surface of which an O-sealing ring rotatably abuts a cylindrical inner surface of the coupling pin (5) is arranged.

16. Cutting tool set according to one of claims 11 to 15, wherein the locking projections (6) on the coupling pin (5) are arranged opposite each other with respect to the longitudinal axis of the hollow cylindrical tube (1).

17. Cutting tool set according to one of claims 11 to 16, wherein the detent projections (6) are dimensioned differently.

18. Cutting tool set according to claim 17, wherein the detent projections (6) are designed as detent wings of different thicknesses.

19. Cutting tool set according to one of claims 11 to 18, wherein the coupling pin (5) has a sealing element, in particular an O-ring, on its outer surface, provided and designed to seal against an inner surface of the coupling sleeve when the coupling pin (5) is inserted into the coupling sleeve (4).

20. Cutting tool set according to one of claims 11 to 19, wherein the coupling pin (5) with the locking projections (6) is formed monolithically.

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