Medical devices, especially for percutaneous surgical / medical procedures

Abstract

In particular, a medical instrument (10) for percutaneous surgical / medical procedures is described, comprising a handle portion (H) designed to allow an operator to handle, orient and manipulate the medical instrument (10), and an elongated rod member (100) fixed to the handle portion (H). The elongated rod member (100) extends from the handle portion (H) to a distal end. At least a portion of the elongated rod member (100) proximate to the distal end is provided with markings (200) that are identifiable under ultrasound examination. The markings (200) are designed as rotationally asymmetric markings (200A, 200B) configured to allow the position and rotational orientation of the elongated rod member (100) to be uniquely detected in an ultrasound image. The markings (200) include first and second rotationally asymmetric markings (200A, 200B) extending in opposite directions along the elongated rod member (100).

Description

[Technical field]

[0001] The present invention relates generally to medical instruments, and more particularly to medical instruments used to perform percutaneous surgical / medical procedures, particularly percutaneous openings of the upper or lower extremities, including but not limited to percutaneous carpal tunnel release and percutaneous A1 pulley release. The present invention is also applicable to other surgical or medical procedures performed under ultrasound guidance, such as but not limited to biopsy, infiltration, injection, puncture, foreign body removal, tendon release, tenotomy, tenotomy-lengthening, aponeurotomy, nerve release, nerve section, and other surgical releases in addition to carpal tunnel release and finger / thumb pulley release, such as treatment of Dupuytren's disease, De Quervain's syndrome, tennis elbow, Morton's neuroma, and generally any percutaneous procedure at any anatomical site. [Background technology]

[0002] Carpal tunnel syndrome (CTS) and trigger finger syndrome (TFS) can be conveniently treated by percutaneous surgical release. These procedures are usually performed using a simple puncture needle, or the more complex hook knife or push knife. Such medical instruments can also be used for other surgical releases of the upper or lower extremities, such as the treatment of Morton's neuroma, tarsal tunnel release, De Quervain's syndrome, epicondylitis, shoulder joint surgery, and similar releases, but this list is not exhaustive.

[0003] Various solutions are known in the art, for example from US Pat. Nos. 5,507,800(A), 5,029,573(A) and 8,603,124(B1), but these solutions are not suitable for performing percutaneous open procedures.

[0004] US Patent Publication US2014 / 0296974(A1) discloses a system and method for assisting in the positioning of a medical instrument. More specifically, the system comprises a hollow tubular member, such as a sheath or sleeve, including a rotation indicator element. The system further comprises an elongated rod having a blade (also called a PMP blade) at its distal end, the rotation indicator element aligned with the orientation of the blade, and a stopper near its proximal end. The blade itself is not designed or configured to function as a cutting device for cutting tissue. Rather, the blade is used to function as a papillary muscle pointer (PMP) for pointing to, i.e., indicating, the location of the space between the papillary muscles of the ventricle. In this regard, the PMP blade exhibits two opposing substantially flat surfaces parallel to each other, in particular to allow the PMP blade to be inserted into the space between the papillary muscles. There is no mention or suggestion that the elongated rod and blade described above can be used to perform a percutaneous open procedure.

[0005] Percutaneous open procedures can be performed using a simple puncture needle. However, this solution is unsatisfactory because the open procedure is not easy to perform and is potentially dangerous to adjacent structures. A more sophisticated solution is disclosed in US Pat. No. 5,782,850(A), but the associated medical device disclosed therein is still relatively complex in construction and may cause undesirable damage to surrounding tissues and structures, especially when the medical device is withdrawn.

[0006] The applicant's International (PCT) Publication No. WO2020 / 003263(A1), the entire contents of which are incorporated herein by reference, discloses various medical instruments for truly percutaneous open procedures, in particular those designed to be used under ultrasound examination, i.e. in combination with an ultrasound examination probe. According to WO2020 / 003263(A1), it is specifically contemplated to provide multiple markings in the form of embossments along different portions of the elongated rod member of the medical instrument, which are designed to be distinguishable under ultrasound examination. Although providing embossments may help to identify the elongated rod member in an ultrasound image and to detect the position of the distal end of the elongated rod member, markings as specifically contemplated in WO2020 / 003263(A1) may not necessarily be sufficient to properly identify the orientation of the elongated rod member and its tip.

[0007] French patent publication FR 2272633 (A1) discloses a type of needle that includes peripheral annular grooves distributed along the length of the needle, the needle being essentially straight, which have the effect of dispersing ultrasound waves, so that the needle can be easily located in an ultrasound image. Further solutions aimed at increasing the echogenicity of medical devices are disclosed in US Patent Nos. US 4,582,061(A), US 4,977,897(A), US 5,490,521(A), US Patent Publication Nos. US 2012 / 0150208(A1), US 2014 / 0265024(A1), US 2016 / 0074130(A1), US 2020 / 0069330(A1) and European Patent Nos. EP 1 132 049(B1), EP 2 384 146(B1).

[0008] While these solutions offer some ability to improve echogenicity, they are not entirely satisfactory in that they are unable to detect the actual rotational orientation of the medical instrument about its axis. Thus, there remains a need for improved solutions that can detect and identify not only the position but also the rotational orientation of an associated elongated rod member of a medical instrument.

[0009] With reference to the medical instruments disclosed in WO2020 / 003263(A1), there remains a need to provide such a medical instrument that has improved echogenicity at the cutting end of the instrument while also having better ability to cut tissue, particularly ligaments, which are moderately tough tissues to cut. Summary of the Invention

[0010] It is a general object of the present invention to provide improved medical instruments, particularly (but not limited to) for percutaneous open procedures, such as percutaneous carpal tunnel release, percutaneous finger / thumb pulley release, of the upper or lower extremities, as well as other percutaneous open procedures used in the treatment of diseases or syndromes, such as those listed in the introductory part of this specification.

[0011] More specifically, it is an object of the present invention to improve the echogenicity of such medical instruments, in particular medical instruments including an elongated rod member extending from a handle portion to a distal end, and preferably curved and / or bent substantially within a defined plane with a view to facilitating identification and detection of the position and rotational orientation of the elongated rod member and in particular its distal end.

[0012] These and other objects are achieved according to a first aspect of the invention by the solution defined in claim 1, namely a medical instrument, in particular for percutaneous surgical / medical procedures, comprising a handle portion designed to allow handling, orientation and manipulation of the medical instrument by an operator, and an elongated rod member fixed to said handle portion, said elongated rod member extending from said handle portion to a distal end. At least a portion of the elongated rod member proximal to the distal end is provided with a marking identifiable under ultrasound examination. According to this first aspect of the invention, the marking is designed as a rotationally asymmetric marking arranged such that the position and rotational orientation of the elongated rod member are uniquely detectable in an ultrasound image. Furthermore, the marking comprises a first and a second rotationally asymmetric marking extending in opposite directions along the elongated rod member.

[0013] According to a particularly preferred embodiment, the first and second rotationally asymmetric markings are first and second rotationally asymmetric grooves formed along the circumference of the elongate rod member.

[0014] Advantageously, each rotationally asymmetric groove may be composed of one or more helical turns. Preferably, the first and second rotationally asymmetric grooves have opposite helical orientations, which in particular facilitates detectability in ultrasound images and facilitates identification of the actual rotational orientation of the medical instrument. More specifically, the distance separating the proximal end of the first rotationally asymmetric groove from the proximal end of the second rotationally asymmetric groove may be substantially equal to the pitch of each rotationally asymmetric groove. The distance and pitch are preferably about 2 mm.

[0015] According to a further advantageous embodiment, each rotationally asymmetric groove may exhibit a width comprised between 0.5 mm and 1 mm and / or a depth comprised between 0.1 mm and 0.2 mm.

[0016] Additionally, in one aspect of an embodiment, the depth of each rotationally asymmetric groove may be constant, while in another aspect of an embodiment, the depth of each rotationally asymmetric groove may vary along the length of the rotationally asymmetric groove, which is particularly advantageous in that it introduces an additional variable that enhances and modulates echogenicity.

[0017] As a further refinement, it is further contemplated that the inner surface of each rotationally asymmetric groove is structured to further enhance echogenicity.

[0018] According to another embodiment of the invention, the elongate rod member is curved and / or bent substantially within a defined plane, and the first and second rotationally asymmetric markings are disposed along a curved section of the elongate rod member proximate the distal end of the elongate rod member or along an angled section. In this latter aspect, the distal end of the elongate rod member preferably includes a tapered end configured to function as a cutting device for cutting tissue, the tapered end being contoured at least in part by a first surface and an opposing second surface, i.e., a first inclined surface that is inclined relative to the defined plane and a second concave surface that is substantially parallel to the defined plane. Indeed, this latter aspect forms another aspect of the invention that is potentially applicable independently of the first aspect of the invention described above.

[0019] According to a second aspect of the invention, as defined in independent claim 14, there is further provided a medical instrument for percutaneous open surgery, comprising a handle portion designed to enable handling, orientation and manipulation of the medical instrument by an operator, and an elongated rod member fixed to the handle portion, the elongated rod member extending from the handle portion to a distal end and being curved and / or bent substantially in a defined plane. The distal end of the elongated rod member comprises a tapered end configured to function as a cutting device for cutting tissue. According to this second aspect of the invention, the tapered end of the elongated rod member is at least partially delineated by a first surface and an opposite second surface, i.e. a first inclined surface inclined relative to the defined plane and a second concave surface substantially parallel to the defined plane.

[0020] The particular configuration of the tapered end of the elongated rod member is particularly intended to enhance the echogenicity of the distal end of the medical device, and additional measures can be considered with a view to further enhancing the echogenicity of the distal end of the medical device, such as:

[0021] Preferably, the tapered end of the elongate rod member may be further defined by a pair of side surfaces forming a lateral incline laterally to at least a portion of the inclined surface and at least a portion of the concave surface. In this embodiment, the inclination angle of each side surface relative to the concave surface is preferably comprised between 25° and 35°.

[0022] Furthermore, the inclination angle of the plane containing the inclined surface relative to the defined plane (and thus relative to the concave surface) is comprised between 10° and 15°.

[0023] According to an advantageous embodiment, the thickness of the tapered end, measured perpendicular to the defined plane, does not exceed 1 mm and / or the width of the tapered end, measured in the defined plane, does not exceed 2 mm.

[0024] According to an advantageous aspect of the invention, the tapered end includes a longitudinal ridge projecting away from the concave surface. The presence of this longitudinal ridge is useful in that it results in an improved echogenicity of the tapered end. Preferably, the height of the longitudinal ridge, measured perpendicular to the defined plane, does not exceed 0.5 mm. Furthermore, the leading edge of the longitudinal ridge can be tapered and can be provided to terminate short of the leading edge of the tapered end with a view to further minimizing interference during the insertion of the medical instrument in the area to be treated and to avoid affecting the cutting properties and sharpness of the leading edge of the tapered end.

[0025] Preferably, the elongate rod member extends along a generatrix and the lateral width of the elongate rod member measured at any point along the generatrix, including the distal end of the elongate rod member, does not exceed 2mm.

[0026] Further, the cross-sectional area of ​​the elongated rod member is preferably less than 2.5 mm 2 not exceed.

[0027] Furthermore, the elongate rod member may have a substantially circular or polygonal cross-section, particularly upstream of the distal end of the elongate rod member, the lateral width of which does not exceed 1.5 mm.

[0028] Further advantageous embodiments of the invention are described below. [Brief description of the drawings]

[0029] Other characteristics and advantages of the invention will appear more clearly on reading the following detailed description of embodiments of the invention given purely as non-limiting examples and illustrated by the attached drawings, in which: [Figure 1] FIG 1A is a perspective view of a medical device according to a first embodiment of the present invention, which is particularly suitable for percutaneous carpal tunnel release in the treatment of carpal tunnel syndrome. FIG 1B is a perspective view of the medical device of FIG 1A from a different angle. FIG 1C and FIG 1D are enlarged views of the distal end (or tip) of the elongated rod member of the medical device shown in FIG 1A and FIG 1B, respectively. [Diagram 2] FIG. 2A is a side view of an elongated rod member of a medical device according to one aspect of the first embodiment shown in FIGS. 1A-1D, shown perpendicular to a defined plane in which the elongated rod member extends. FIG. 2B is an enlarged view of the distal end of the elongated rod member of FIG. 2A, showing the tapered end in more detail. FIG. 2C is an enlarged side view of the tapered end of the elongated rod member of FIGS. 2A and 2B. FIG. 2D is a cross-sectional view of the tapered end shown in FIGS. 2B and 2C, taken along section AA identified in FIG. 2B. FIG. 2E is a partially cutaway perspective view of an enlarged view of a portion of the markings provided along a portion of the elongated rod member of FIG. 2A proximate to the distal end. [Diagram 3] Figure 3A is an enlarged side view of a tapered end of an elongate rod member of a medical device according to a further aspect of the embodiment shown in Figures 1A-1D and 2A-2E, and Figure 3B is a cross-sectional view of the tapered end shown in Figure 3A taken along the same cross section as Figure 2D. [Figure 4] FIG. 4 is an enlarged side view of a tapered end of an elongate rod member of a medical device according to one aspect of the embodiment shown in FIGS. 3A and 3B. [Diagram 5] Figure 5A is a perspective view of a medical device according to a second embodiment of the present invention, which is particularly suitable for percutaneous A1 pulley release in the treatment of trigger finger syndrome. Figure 5B is a perspective view of the medical device of Figure 5A from a different angle. Figures 5C and 5D are close-up views of the distal end (or tip) of the elongated rod member of the medical device shown in Figures 5A and 5B, respectively. [Figure 6]FIG. 6A is a side view of an elongate rod member of a medical device according to one aspect of the second embodiment shown in FIGS. 5A-5D, shown perpendicular to a defined plane in which the elongate rod member extends. FIG. 6B is an enlarged view of the distal end of the elongate rod member of FIG. 6A, showing the tapered end in more detail. FIG. 6C is an enlarged side view of the tapered end of the elongate rod member of FIGS. 6A and 6B. FIG. 6D is a cross-sectional view of the tapered end shown in FIGS. 6B and 6C, taken along section BB identified in FIG. 6B. FIG. 6E is an enlarged view of a portion of the markings provided along a portion of the elongate rod member of FIG. 6A proximate to the distal end. [Figure 7] Figure 7A is an enlarged side view of a tapered end of an elongate rod member of a medical device according to a further aspect of the embodiment shown in Figures 5A-5D and 6A-6E, and Figure 7B is a cross-sectional view of the tapered end shown in Figure 7A taken along the same cross section as Figure 6D. [Figure 8] FIG. 8 is an enlarged side view of a tapered end of an elongate rod member of a medical device according to one aspect of the embodiment shown in FIGS. 7A and 7B. [Figure 9] Figure 9A is a photographic representation of an ultrasound image showing a distal portion of an elongate member of a medical instrument provided with markings according to the present invention, such as those shown in Figures 5A-5D and 6A-6E, in a first rotational orientation, while Figures 9B and 9C are photographic representations of ultrasound images showing the distal portion of the elongate member of the medical instrument of Figure 9A in two further rotational orientations. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0030] The present invention will be described with reference to various exemplary embodiments, it being understood that the scope of the present invention, as defined in the appended claims, encompasses all combinations and subcombinations of the features of the medical devices disclosed herein.

[0031] As described herein, when two or more parts or components are described as being connected, attached, fixed or coupled to one another, they may be so connected, attached, fixed or coupled to one another directly or through one or more intermediate parts.

[0032] 1A-1D, there is shown a first embodiment of a medical device according to the present invention, generally designated 10, which is particularly suitable for percutaneous carpal tunnel release in the treatment of carpal tunnel syndrome (CTS). Variations of this first embodiment are further shown in FIGS. 2A-2E, 3A, 3B and 4.

[0033] Referring to FIG. 5A to FIG. 5D, reference numeral 10 * Another embodiment of the medical device according to the present invention is shown in FIG. 1, which is particularly suitable for percutaneous A1 pulley release in the treatment of Trigger Finger Syndrome (TFS). Variations of this second embodiment are further shown in FIGS. 6A-6E, 7A, 7B and 8.

[0034] The medical device 10, 10 * is specifically designed for use under ultrasound inspection, i.e. in combination with an ultrasound inspection probe.

[0035] All embodiments include a handle portion H, H designed to allow handling, orientation and manipulation of the medical instrument by an operator, such as a surgeon or physician (including, for example, a radiologist or rheumatologist). * (not shown in Figs. 2A to 2E to 4 and Figs. 6A to 6E to 8) and handle portions H, H * and an elongated rod member 100, 100 extending therefrom to a distal end. * The elongated rod members 100, 100 share many common features, including * is substantially curved and / or bent within a defined plane designated P0.

[0036] As shown, elongated rod members 100, 100 * The first linear section is substantially the handle portion H, H * along a first direction in the defined plane P0, i.e., away from the handle portions H, H * The elongated rod members 100, 100 extend parallel to the longitudinal axis of the * The remaining portion downstream of the first straight section is curved and / or bent within the defined plane P0. The reference GX in Figures 2A, 2B, 6A and 6B indicates a generatrix along which the elongated rod members 100, 100 * The elongated rod members 100, 100 * The free ends of the first straight sections (see Figs. 2A and 6A) are now provided with handle parts H, H * It is bent at 90° to provide a

[0037] Additionally, as will be described in more detail below, the elongated rod members 100, 100 * The distal end of each of the distal ends 100A, 100A', 100A'', 100A's are configured to function as a cutting device for cutting tissue. * , 100A ** , 100A *** The tapered ends 100A, 100A', 100A'', 100A * , 100A ** , 100A *** This particular configuration forms an aspect of the invention.

[0038] With more specific reference to the embodiment of Figures 1A-1D and 2A-2E (this discussion also applies to the embodiment shown in Figures 3A, 3B and 4), the elongated rod member 100 includes a curved section 100a that extends over an angle α1 of more than 60° (see Figure 2A, which applies by analogy to the embodiments of Figures 1A-1D, 3A, 3B and 4). The radius of curvature R1 of the curved section 100a is about 30-45 mm. For example, the angle α1 and the radius of curvature R1 can be selected to be equal to about 68° and 37 mm, respectively, although those values ​​should not be considered as limiting the scope of the present invention. It will be appreciated that in this example, the terminal section 100b of the elongate rod member 100 (including the tapered ends 100A, 100A', 100A'' described above) is bent at an angle α2 of approximately 20° (here 22°) relative to the end of the curved section 100a, such that the terminal section 100b extends substantially perpendicular to the direction in which the first straight section of the elongate rod member 100 extends (i.e., substantially perpendicular to the longitudinal axis of the handle portion H).

[0039] For example, the overall length L1 of the elongate rod member 100 measured in the longitudinal direction (see FIG. 2A) may be about 125 mm, the length L2 of the first straight section of the elongate rod member 100 may be about 90 mm, and the length L3 of the distal section 100b (including tapered ends 100A, 100A', 100A'') of the elongate rod member 100 may be about 4 mm. In the illustrated example, the length L0 of the bent portion at the free end of the first straight section of the elongate rod member 100 is about 4 mm.

[0040] Preferably, the transverse width of the elongated rod member 100 measured at any point along the generatrix GX, including the distal end of the elongated rod member 100, does not exceed 2 mm. More specifically, in the illustrated example, the elongated rod member 100 preferably has a substantially circular cross-section with a diameter D not exceeding 1.5 mm upstream of the distal end of the elongated rod member 100. However, other cross-sectional shapes are also contemplated, including triangular, square, rectangular, trapezoidal, hexagonal and other polygonal cross-sections, also preferably with a transverse width not exceeding 1.5 mm. Polygonal cross-sections may be advantageous over circular cross-sections in that echogenicity is further improved.

[0041] More generally, the cross-sectional area of ​​the elongate rod member 100 (including the tapered ends 100A, 100A', 100A'') is preferably less than 2.5 mm 2 In other words, the elongated rod member 100 has a particularly thin needle-like shape, which is advantageous for inserting and withdrawing the medical device 10 without damaging the surrounding tissue or structure.

[0042] The illustrated arc shape allows the medical instrument 10 to be introduced into the ultrasound field, under or against the structure being opened, without interference between the handle portion of the instrument and the ultrasound probe throughout the procedure. This shape also allows the medical instrument to be withdrawn without risk of causing undesired damage to the surrounding soft tissue.

[0043] With reference to the embodiment of FIGS. 5A-5D and 6A-6E (this discussion also applies to the embodiment shown in FIGS. 7A, 7B and 8), an elongated rod member 100 * The elongated rod member 100 * three substantially linear sections 100a at an angle to the first linear section of * , 100b * , 100c * In the illustrated example, each curved section has an angle α1 of about 35°. * , α2* , α3 * 100a, which has an angled section 100a * , 100b * , 100c * However, the elongated rod member 100 * The angled end sections 100c are at angles of about 35°, 70°, and 105°, respectively, relative to the first straight section 100a. In other words, the angled end sections 100c are at angles of about 35°, 70°, and 105° relative to the first straight section 100b. * The elongated rod member 100 * The first straight section of the handle portion H is slightly rearward, but approximately perpendicular to the direction of extension of the first straight section of the handle portion H. * The longitudinal axis of the casing extends substantially perpendicular to the longitudinal axis of the casing.

[0044] For example, the length of the elongated rod member 100 measured in the longitudinal direction (see FIG. 6A) * Total length L1 * The length of the elongated rod member 100 may be about 90 mm. * The length of the first straight section L2 * Approximately 60 mm, and the angled section 100a * , 100b * The length of each of L3 * , L4 * The elongated rod member 100 may be about 20 mm. * End section 100c * (Tapered end 100A * , 100A ** , 100A *** (including length L5) * In the illustrated example, the elongated rod member 100 * The length L0 of the bent portion at the free end of the first straight section * is about 4 mm.

[0045] Preferably, the elongated rod member 100 * The length of the elongated rod member 100 measured at any point along the generatrix GX including the distal end of the *The lateral width of the elongated rod member 100 likewise does not exceed 2 mm. More specifically, in the illustrated example, * Similarly, the elongated rod member 100 * upstream of the distal end of the * The conductor has a substantially circular cross-section not exceeding 1.5 mm. Other cross-sectional shapes, including polygonal cross-sections, are contemplated as well.

[0046] More generally, an elongated rod member 100 * (Tapered end 100A * , 100A ** , 100A *** The cross-sectional area of ​​the 2 In other words, the elongated rod member 100 * The medical device 10 is inserted into the puncture needle without damaging the surrounding tissue or structure. * The particularly thin shape is advantageous for easy insertion and withdrawal of the catheter.

[0047] Similarly, the angled configuration shown allows the medical instrument 10 to be positioned beneath or against structures being opened into the ultrasound field throughout the procedure without interference between the handle portion of the instrument and the ultrasound probe. * Similarly, this shape allows the medical device to be withdrawn without the risk of causing undesired damage to the surrounding soft tissue.

[0048] Therefore, the elongated rod members 100, 100 * It will be appreciated that a portion of the curved or bent portion of the can be utilized as a fulcrum to facilitate the cutting of the desired tissue, particularly during surgery, and in fact a portion of the curved or bent portion can advantageously be used to support on the tissue underneath, or on an additional instrument inserted for that very purpose, thereby providing support for the manipulation of the medical instrument during the cutting operation.

[0049] The medical device of the present invention also advantageously comprises an essentially elongated rod member 100, 100 *It will also be appreciated that the cross-sectional area of ​​the elongated member is limited (preferably less than 2.5 mm as discussed above) and thus provides a minimum cross-section corresponding to a cross-section of 1.5 mm 2 , which greatly facilitates penetration of tissue with minimal interference both during insertion of the medical instrument into the area to be treated and during its withdrawal. 2 This allows the procedure to be performed in a truly percutaneous manner, with only a puncture and without the need for an incision at the point of entry of the medical instrument, thereby allowing the patient to be treated without any noticeable scars, just as after an infusion.

[0050] In accordance with an important aspect of the present invention, as shown in FIGS. 1A-1D, 2A, 2E, 5A-5D, 6A and 6E, an elongated rod member 100, 100 adjacent its distal end is * At least a portion of the * More specifically, the markings 200, 200 * are designed as rotationally asymmetric markings configured to allow the position and rotational orientation of the elongated rod member to be uniquely detected in an ultrasound image. * is adapted to produce unique specific echoes in the ultrasound image depending on the actual rotational orientation of the medical instrument in the ultrasound field.

[0051] 1A-1D, 2A-2E (this discussion applies equally to the embodiment shown in FIGS. 3A, 3B and 4), the marking 200 is preferably disposed on the curved section 100a such that a central portion of the marking 200 is positioned at an angle β of about 45° relative to the distal section 100b of the elongated rod member 100, as shown in FIG. 2A. With reference to the embodiment shown in FIGS. 5A-5D, 6A-6E (this discussion applies equally to the embodiment shown in FIGS. 7A, 7B and 8), the marking 200 is preferably disposed on the curved section 100a such that a central portion of the marking 200 is positioned at an angle β of about 45° relative to the distal section 100b of the elongated rod member 100, as shown in FIG. * Preferably, the second angled section 100b is provided as shown in FIG. * Distal end of and marking 200 * Distance d between* The second angled section 100b is about 4 mm. * In this way, the markings 200, 200 * The elongated rod members 100, 100 * 100A, 100A′, 100A″, 100A′, 100B′, 100C′, 100D′, 100E′, 100F′, 100G′, 100H′, 100I ... * , 100A ** , 100A *** This makes it possible to identify and detect the position and rotational direction of the

[0052] Such detection can be performed visually by a trained operator, or automatically or semi-automatically using dedicated image processing software to properly identify the relevant echoes / markers in the ultrasound image. In this case, in particular, the relevant markings 200, 200 * It is contemplated that a medical instrument may be automatically located and oriented within an ultrasound image using a 3D model to provide visual assistance to the operator, which may include, in particular, overlaying a virtual representation of the medical instrument on the ultrasound image in real time, if desired.

[0053] As shown in more detail in FIGS. 1C, 1D and 5C, 5D, the markings 200, 200 * The elongated rod members 100, 100 * As shown, the two rotationally asymmetric grooves 200A, 200B, and 200A are formed along the outer periphery of the * , 200B * The elongated rod members 100, 100 * In the illustrated example, the grooves 200A, 200B, and 200A extend in opposite directions along the * , 200B * are here essentially mirror images of each other.

[0054] More specifically, each of the asymmetric grooves 200A, 200B, 200A* , 200B * consists of one helical turn, i.e. one turn of a helix having a deployment angle of approximately 360°. However, multiple helical turns are also conceivable. Furthermore, in the illustrated example, the first and second rotationally asymmetric grooves 200A, 200B, 200A * , 200B * However, advantageously, the first grooves 200A, 200A have opposite helical orientations. * in the form of a left-handed (i.e., counterclockwise) spiral and tapered ends 100A, 100A * while the second groove 200B, 200B * in the form of a right-handed (i.e., clockwise) spiral and tapered ends 100A, 100A * Preferably, the first groove 200A, 200A * and the second groove 200B, 200B * Distance D separating the proximal ends of S is the pitch of each groove P S In the illustrated example, the distance D S and pitch P S is about 2 mm.

[0055] Referring to the illustrated embodiment, and in particular to FIGS. 1C, 1D and 5C, 5D, an elongated rod member 100, 100A for an ultrasound probe is provided. * Depending on the actual direction of rotation of the tip of the groove 200A, 200B, 200A * , 200B * It will be appreciated that the present invention provides a method for detecting echoes that are distinct from one another, and that exhibit two to four depressions in the incident ultrasound waves generated by an ultrasonic probe, thereby producing echoes that are distinct and have unique and distinct spacing and / or distribution.

[0056] 9A is a photographic illustration of an ultrasound image showing a distal end portion of an elongate member of a medical device provided with markings in accordance with the present invention, as shown, for example, in FIGS. 5A-5D and 6A-6E. The surface of the elongate rod member shown in FIG. 9A includes associated grooves 200A and 200C. * , 200B *9A also shows four recesses (indicated by solid arrows) with associated "shadows" (indicated by dashed arrows) in the ultrasound image that represent the presence of the associated grooves. These echoes and markers can be used to identify the actual rotational orientation of the medical device about its axis. Also visible in FIG. 9A is an echo generated by the tapered end of the medical device (indicated by dotted arrows), which is further enhanced by the presence of the longitudinal ridges, as will be described in more detail below.

[0057] 9B is a photographic illustration showing the distal end portion of the elongate member of the medical device of FIG. 9A in a different rotational orientation, with only two depressions (indicated by continuous arrows) still visible on the surface of the elongate rod member. * , 200B * Because the spiral orientations of the recesses are in opposite directions, the spacing between the recesses changes as a function of the rotational orientation of the medical device, as highlighted by FIG. 9C, thereby indicating that the medical device is further oriented at different rotational orientations.

[0058] Each of the rotationally asymmetric grooves 200A, 200B, 200A * , 200B * is preferably a width w0 comprised between 0.5 mm and 1 mm (see Figs. 2A and 2E), w0 * (See FIG. 6E). In the illustrated example, the widths w0 and w0 * The depth of each groove is relatively small and is advantageously comprised between 0.1 mm and 0.2 mm (see Fig. 2E and Fig. 6E / such depths are denoted by the symbols d0, d0 * (denoted by ).

[0059] In one embodiment, each of the rotationally asymmetric grooves 200A, 200B, 200A * , 200B * In another embodiment, the depth of each of the rotationally asymmetric grooves 200A, 200B, 200A may be constant. * , 200B *The depth of may advantageously vary along the length of the groove, thereby adding an additional variable of differentiated echogenicity depending on the actual rotational orientation of the marking in the ultrasound field.

[0060] Further means for enhancing echogenicity include rotationally asymmetric grooves 200A, 200B, 200A * , 200B * 3. The invention relates to a method for structuring the inner surface of each of the rotationally asymmetric grooves 200A, 200B, 200A, 200B, 200C, 200D, 200E, 200F, 200G, 200H, 200I ... * , 200B * The structuring of the inner surface of the grooves 200A, 200B, 200A * , 200B * This can also have a positive effect on tactile feedback, as the tip tends to cling slightly to the surrounding soft tissue, and can help the operator "feel" where the distal tip of the medical instrument is.

[0061] Each groove 200A, 200B, 200A * , 200B * The particular profile of the groove can be further modified to produce a characteristic dispersion of the ultrasound waves impinging on the inner surface of the groove. Specifically, the groove profile can be essentially cylindrical or can exhibit some degree of asymmetry.

[0062] It will be appreciated that other marking configurations are contemplated as long as the markings retain their overall rotationally asymmetric configuration. For example, in the illustrated example, one of the two grooves 200A, 200B or groove 200A * , 200B * One of them is marked 200, 200 * , which would still maintain its overall rotational asymmetry, but the illustrated solution has the advantage that it is more easily discernible in an ultrasound image.

[0063] Further aspects of the present invention, which are applicable independently of the use of markings as described above, will now be described with particular reference to Figures 1C, 1D, 2B-2D, 3A, 3B, 4, 5C, 5D, 6B-6D, 7A, 7B and 8, namely, elongated rod members 100, 100 * Tapered end of 100A, 100A', 100A'', 100A * , 100A ** , 100A *** As shown, the tapered ends 100A, 100A', 100A'', 100A * , 100A ** , 100A *** are a first surface and an opposite second surface SA, SB, SA * , S.B. * , i.e., a first inclined surface SA, SA inclined relative to a defined plane P0 * and a second concave surface SB, SB substantially parallel to the defined plane P0. * Preferably, the tapered ends 100A, 100A', 100A'', 100A are at least partially delineated by * , 100A ** , 100A *** is the inclined surface SA, SA * At least a part of the concave surface SB, SB * A pair of side surfaces SC, SC forming a side slope (see, in particular, Figs. 1C, 2B to 2D, 3A, 3B, 4, 5C, 6B to 6D, 7A, 7B and 8) on at least a part of the side of the * The tapered ends 100A, 100A', 100A'', 100A are further delineated by * , 100A ** , 100A *** At the leading and lateral edges of the cutting edge, particularly sharp cutting edges can be achieved.

[0064] 2B-2D more specifically (this consideration also applies by analogy to the embodiment shown in FIGS. 3A, 3B and 4), the length LA of the inclined surface SA and the length LB of the tapered tip of the elongate rod member 100, measured in a defined plane P0 (see FIG. 2B), are in the illustrated example approximately 1.5 mm and 2.6 mm, respectively. The width w of the tapered end 100A, 100A', 100A'', also measured in the defined plane P0, is here, for example, approximately 1.8 mm, i.e. slightly larger than the associated diameter D of the elongate rod member 100. Ideally, this width w should not exceed 2 mm. The length LC of the concave surface SB (and of the tapered ends 100A, 100A', 100A'') is approximately 1.8 mm in the illustrated example, and the thickness t of the tapered ends 100A, 100A', 100A'', measured perpendicular to the defined plane P0, is approximately 0.3 mm (see Figures 2C, 3A and 4).

[0065] 3A, 3B and 4 show variants of the tapered end of the elongate rod member 100, designated 100A', 100A'', respectively, aimed at further improving the echogenicity of the tapered end 100A', 100A''. The main difference compared to the embodiment shown in FIGS. 1A-1D and 2A-2E lies in the fact that the tapered end 100A', 100A'' further comprises a longitudinal ridge 150', 150'', projecting away from the concave surface SB. The height h of this longitudinal ridge 150', 150'', measured perpendicular to the defined plane P0, preferably does not exceed 0.5 mm. In the example shown, the height h is approximately 0.3 mm. The width of the longitudinal ridges 150', 150'' measured in the defined plane P0 is a small fraction (eg, 10% to 20%) of the width w of the tapered ends 100A', 100A''.

[0066] Tests conducted by the applicant have demonstrated that the provision of longitudinal ridges 150', 150'' further improves the echogenicity of tapered ends 100A', 100A'' under ultrasound examination.

[0067] It will be appreciated that the presence of the longitudinal ridges 150', 150'' on the concave surface SC results in a local increase in the thickness of the tapered end 100A', 100A'', as compared to the thickness of the tapered end 100A shown in Figures 1A-1D and 2A-2E. Nevertheless, the dimensions of the longitudinal ridges 150', 150'' are selected to minimize interference during insertion of a medical instrument in the area to be treated. Furthermore, the leading edge of the longitudinal ridges 150', 150'' is preferably tapered to further minimize interference during insertion of a medical instrument. It is further noted that the leading edge of the longitudinal ridges 150', 150'' terminates short of the leading edge of the tapered end 100A', 100A'', so as not to affect its cutting characteristics and sharpness. For example, Figures 3A and 4 show that the leading edges of the longitudinal ridges 150', 150'' may be provided with suitable curved (Figure 3A) or chamfered (Figure 4) sections.

[0068] 6B-6D (this discussion also applies to the embodiments shown in FIGS. 7A, 7B and 8), specifically, the inclined plane SA * Length of LA * and an elongated rod member 100 * Length of tapered end LB * are approximately 1.5 mm and 2 mm, respectively, in the illustrated example. * , 100A ** , 100A *** Width w * is, for example, about 1.25 mm, i.e., the elongated rod member 100 * The associated diameter D * Ideally, this width w * should likewise not exceed 2 mm. * (and tapered end 100A * , 100A ** , 100A *** ) Length LC * is approximately 2 mm in the illustrated example, measured perpendicular to the defined plane P0,* , 100A ** , 100A *** Thickness t * is approximately 0.35 mm (see Figures 6C, 7A and 8).

[0069] 7A, 7B and 8 are each labeled 100A ** , 100A *** An elongated rod member 100, denoted by * 1 shows a variation of the tapered end of the tapered end 100A. ** , 100A *** The main difference compared to the embodiment shown in Figures 5A-5D and 6A-6E is the tapered end 100A. ** , 100A *** But the concave surface SB * A longitudinal ridge 150 protruding away from the ** , 150 *** This longitudinal ridge 150, measured perpendicular to the defined plane P0, ** , 150 *** Height h * Preferably, the height h does not exceed 0.5 mm. In the example shown, * is about 0.3 mm. The longitudinal ridge 150, measured in the defined plane P0 ** , 150 *** The width of the tapered end is 100A ** , 100A *** Width w * It is only a small fraction (e.g., 10% to 20%) of

[0070] Tests conducted by the applicant have shown that the longitudinal ridges 150 ** , 150 *** Similarly, by providing a tapered end 100A under ultrasonic inspection, ** , 100A *** It has been demonstrated that the echogenicity of

[0071] Concave surface SC * Upper longitudinal ridge 150 **, 150 *** 5A-5D and 6A-6E. * Compared to the thickness of the tapered end 100A ** , 100A ** It will be appreciated that the thickness of the longitudinal ridge 150 is locally increased. ** , 150 *** The dimensions of the longitudinal ridges 150 are similarly selected to minimize interference during insertion of medical instruments in the area to be treated. ** , 150 *** The leading edge of the longitudinal ridge 150 is preferably tapered to further minimize interference during insertion of the medical instrument. ** , 150 *** The leading edge of the 100A is tapered so as not to affect its cutting characteristics and sharpness. ** , 100A *** 7A and 8 show longitudinal ridge 150. ** , 150 *** It is shown that the leading edge of the casing may be provided with a suitable curved section (FIG. 7A) or chamfered section (FIG. 8).

[0072] The inclined planes SA, SA with respect to the defined plane P0 (see FIGS. 2C, 3A, 4, 6C, 7A and 8). * The inclination angles γ and γ of the plane containing * is preferably comprised between 10° and 15°, while the angle (i.e., the concave surface SB, SB * 2D, 3B, 4D and 7D), lateral SC, SC * The inclination angles δ and δ * is preferably between 25° and 35°.

[0073] As can be seen from the above description, the medical device of the present invention is of simple construction and therefore can be manufactured quite economically.

[0074] Advantageously, as shown in FIGS. 1A, 1B and 5A, 5B, a visible marking (such as a laser marking) is provided on the handle portion H, H in order to identify the orientation of the medical instrument when performing the operation, i.e. when the distal end of the medical instrument is inserted into the area to be treated. * The visible markings may be provided, in particular, on the tapered ends 100A, 100A', 100A'', 100A. * , 100A ** , 100A *** Handle parts H and H facing the same direction * The inner surface of the groove may be provided with a groove.

[0075] In the drawings of FIGS. 1A-1D to 8, elongated rod members 100, 100 * are shown as being solid and not hollow. However, it is conceivable to use hollow rod members instead, which may provide the functionality of detecting possible bleeding via the associated rod cavity in case of blood vessel damage, and / or the functionality of injecting a local anesthetic (or other agent such as a steroid or corticosteroid) using a dedicated syringe inserted into the associated rod cavity. In this case, the handle portions H, H of the medical instrument are shown to show corresponding cavities which also communicate with the rod cavities, e.g. to allow injection of a local anesthetic or to provide a window to allow observation of possible blood reflux. * It is advantageous to further adapt

[0076] As already mentioned, the medical instrument of the invention can be used in particular for performing percutaneous open procedures of the upper or lower limbs, with the aid of ultrasound examination. However, other applications are also conceivable. Moreover, the application of the relevant markings described above can also be envisaged for medical instruments not necessarily designed for performing percutaneous open procedures, but can be applied to any medical instrument designed to carry out other surgical or medical procedures, such as, for example, biopsy probes or devices designed for removing foreign bodies.

[0077] For example, the release of the transverse carpal ligament (TCL) using the medical device 10 described above, or * With regard to the associated surgical procedure for the release of the A1 pulley using the same, such surgical procedure can be performed in essentially the same manner as previously disclosed in the applicant's International (PCT) Publication No. WO2020 / 003263(A1).

[0078] Various modifications and / or improvements can be made to the above-described embodiments without departing from the scope of the invention as defined by the appended claims. In particular, although the embodiments of the invention have been described for performing a percutaneous carpal tunnel release and a percutaneous A1 pulley release, the invention is generally applicable to any percutaneous release of the upper or lower extremities, or other parts of the body, such as the neck or spine.

[0079] With regard to the configuration of the associated markings that are identifiable under ultrasonic inspection, it will be understood that such markings can take any other suitable shape or structure and do not necessarily have to consist of two separate grooves formed in the circumference of the elongated rod member as shown in the drawings. In fact, the two grooves can be merged into a common groove structure by connecting the proximal ends of the grooves to each other. Furthermore, the markings can include a series of dimples that are non-uniformly distributed around a portion of the circumference of the elongated rod member, or other suitable structures or patterns that impart rotational asymmetry to the markings. However, machining the grooves remains a cost-effective solution to form the desired markings.

[0080] 1A-1D through 8 show medical devices in which the tapered ends are strictly planar, the claims should be construed to encompass all manner in which the surfaces are generally planar or exhibit slight curvature, such as being slightly concave or convex. As a convention, the plane of the relevant surfaces may generally be defined as the plane that most closely approximates each surface under consideration.

[0081] Additionally, longitudinal ridges 150', 150'', 150 ** , 150 *** Although the cross-section is shown as being substantially rectangular (which gives very good results), such cross-section may alternatively exhibit a V-shape, a trapezoidal shape, a rounded shape, or any other suitable shape that enhances the echogenicity of the tapered end of the medical instrument. [Explanation of symbols]

[0082] 10 Medical device according to the present invention (first embodiment) H Handle portion of medical instrument 10 100: Elongated rod member of medical device 10 extending in a defined plane P0 100a (single) curved section of elongated rod member 100 100b: a distal section of elongated rod member 100 including tapered ends 100A, 100A', 100A'' 100A: Tapered end of elongated rod member 100 designed to function as a cutting device for cutting tissue (FIGS. 1A-1D, 2A-2E) 100A' Tapered end of elongated rod member 100 designed to function as a cutting device to cut tissue (a variation of FIGS. 3A and 3B) 100A″ Tapered end of elongated rod member 100 designed to function as a cutting device to cut tissue (variant of FIG. 4) 150' Longitudinal ridge projecting away from concave surface SB (variant of Figs. 3A and 3B) 150'' Longitudinal ridge protruding away from concave surface SB (variant of FIG. 4) 200 Rotationally asymmetric markings identifiable under ultrasonic inspection 200A A (first) rotationally asymmetric groove (e.g., a left-handed spiral) formed along the circumference of the elongated rod member 100 proximate its distal end. 200B A (second) rotationally asymmetric groove (e.g., a right-handed spiral) formed along the circumference of the elongated rod member 100 proximate its distal end. SA: an inclined surface (first surface) outlining the first surface of the tapered end 100A, 100A', 100A'' / a surface inclined with respect to a defined plane P0 SB: a concave surface (second surface) outlining the second surface opposite the first surface of the tapered ends 100A, 100A', 100A'' / surface substantially parallel to the defined plane P0 SC: A pair of side surfaces forming a side slope beside at least a portion of the inclined surface SA and at least a portion of the concave surface SB. D diameter (or lateral width) of the elongated rod member 100 L0: Length of the bent portion at the proximal end of the elongated rod member 100 L1: Total length of the elongated rod member 100 L2 is the length of the (first) straight section of the elongated rod member 100 L3: Length of terminal section 100b (including tapered ends 100A, 100A', 100A'') LA is the approximate length of the inclined surface SA, measured in the defined plane P0 LB is the approximate length of the tapered end of the elongated rod member 100 measured in the defined plane P0 LC is the approximate length of the concave surface SB / tapered end 100A, 100A', 100A'', measured in the defined plane P0 h is the approximate height of the longitudinal ridges 150', 150'', measured perpendicular to the defined plane P0 R1 - radius of curvature of curved section 100a Angle of α1 curved section 100a α2: the angle of the bend at the junction between the curved section 100a and the terminal section 100b β angle between end section 100b and the central portion of marking 200 γ The inclination angle of the inclined surface SA with respect to the specified plane P0 δ The inclination angle of the side surface SC relative to the defined plane P0 / concave surface SB w is the width of the tapered ends 100A, 100A', 100A'', measured in the defined plane P0 t thickness of tapered end 100A measured perpendicular to defined plane P0 / thickness of tapered end 100A', 100A'' (excluding longitudinal ridges 150', 150'') measured perpendicular to defined plane P0 w0 Width of rotationally asymmetric grooves 200A, 200B 10 * Medical device according to the present invention (second embodiment) H * Medical equipment 10 * Handle part 100 * A medical device 10 extending in a defined plane P0 * A thin rod member 100a * Elongated rod member 100 * (First) Angled Section 100b * Elongated rod member 100 * (Second) angled section 100c * Elongated rod member 100 * (Third) angled section (tapered end 100A * , 100A ** , 100A *** An elongated rod member 100 including * (end section of 100A * An elongated rod member 100 designed to function as a cutting device for cutting tissue. * Tapered end of 100A ** A tapered end of an elongated rod member 100 designed to function as a cutting device to cut tissue (a variation of FIGS. 7A and 7B ). 100A *** A tapered end of the elongated rod member 100 designed to function as a cutting device to cut tissue (variant of FIG. 8) 150 ** Concave surface SB * Longitudinal ridges projecting away from the 150 *** Concave surface SB *Longitudinal ridges projecting away from the 200 * Rotationally asymmetric markings visible under ultrasonic inspection 200A * Elongated rod member 100 * a (first) rotationally asymmetric groove (e.g., a left-handed spiral) formed along the circumference of the 200B * Elongated rod member 100 * a (second) rotationally asymmetric groove (e.g., a right-handed spiral) formed along the circumference of the SA * Tapered end 100A * , 100A ** , 100A *** An inclined surface (first surface) outlining the first surface of the S.B. * Tapered end 100A * , 100A ** , 100A *** A concave surface (second surface) that outlines the second surface opposite to the first surface of the SC * Slope SA * and at least a part of the concave surface SB * A pair of side surfaces forming a side slope beside at least a portion of D * Elongated rod member 100 * diameter (or lateral width) L0 * Elongated rod member 100 * Length of the bent portion at the proximal end of L1 * Elongated rod member 100 * Total length L2 * Elongated rod member 100 * The length of the (first) straight section L3 * (First) Angled Section 100a * Length L4 *(Second) angled section 100b * Length L5 * (Third) Angled Section 100c * Length LA * The inclined plane SA, measured in the defined plane P0 * Approximate length of LB * The elongated rod member 100 is measured in a defined plane P0. * Approximate length of the tapered end of LC * Concave surface SB, measured in a defined plane P0 * / Tapered end 100A * , 100A ** , 100A *** Approximate length of h * Longitudinal ridge 150, measured perpendicular to a defined plane P0 ** , 150 *** Approximate height of d * (Second) angled section 100b * Distal end of and marking 200 * Distance between α1 * Elongated rod member 100 * (First) straight section and (First) angled section 100a * The angle of the curved section between α2 * (First) Angled Section 100a * and (second) angled section 100b * The angle of the curved section between Alpha 3 * (Second) angled section 100b * and (third) angled section 100c * The angle of the curved section between Gamma * Inclined surface SA relative to the specified plane P0 * Tilt angle δ * Defined plane P0 / concave surface SB* Aspects of SC * Tilt angle w * Tapered end 100A, measured in a defined plane P0 * , 100A ** , 100A *** Width t * Tapered end 100A, measured perpendicular to a defined plane P0 * thickness of the tapered end 100A, measured perpendicular to the defined plane P0 ** , 100A *** Thickness (longitudinal ridge 150 ** , 150 *** (Excluding w0 * Rotationally asymmetric groove 200A * , 200B * Width d0 * Rotationally asymmetric groove 200A * , 200B * Depth D S First rotationally asymmetric groove 200A, 200A * and a second rotationally asymmetric groove 200B, 200B * Distance between the proximal end of P S Rotationally asymmetric grooves 200A, 200B, 200A * , 200B * The pitch of the helical turns that form GX Long and thin rod member 100, 100 * A busbar with P0 Elongated rod member 100, 100 * A defined plane in which

Claims

1. A medical device, in particular a medical device for percutaneous surgical / medical procedures (10; 10*), a handle portion (H; H*) designed to enable an operator to handle, orient and manipulate the medical instrument (10; 10*), and an elongated rod member (100; 100*) fixed to said handle portion (H; H*), the elongated rod member (100; 100*) extends from the handle portion (H; H*) to a distal end, At least a portion of the elongated rod member (100; 100*) adjacent to the distal end is provided with a marking (200; 200*) that is identifiable under ultrasound examination; the markings (200; 200*) are designed as rotationally asymmetric markings configured so that the position and rotational orientation of the elongated rod member (100; 100*) can be uniquely detected in an ultrasound image, 1. A medical device, comprising: a first and second rotationally asymmetric markings (200A, 200B; 200A*, 200B*) extending in opposite directions along said elongate rod member (100; 100*).

2. 2. The medical device (10; 10*) according to claim 1, A medical device characterized in that the first and second rotationally asymmetric markings are first and second rotationally asymmetric grooves (200A, 200B; 200A*, 200B*) formed along the outer periphery of the elongated rod member (100; 100*).

3. 3. The medical device (10; 10*) according to claim 2, A medical device characterized in that each rotationally asymmetric groove (200A, 200B; 200A*, 200B*) consists of one or more helical turns.

4. A medical device (10; 10*) according to claim 3, A medical device characterized in that said first and second rotationally asymmetric grooves (200A, 200B; 200A*, 200B*) have opposite helical directions.

5. A medical device (10; 10*) according to claim 3, A medical device characterized in that the distance (DS) separating the proximal end of the first rotationally asymmetric groove (200A; 200A*) and the proximal end of the second rotationally asymmetric groove (200B; 200B*) is substantially equal to the pitch (PS) of each rotationally asymmetric groove (200A, 200B; 200A*, 200B*).

6. A medical device (10; 10*) according to claim 5, A medical device characterized in that the distance (DS) and the pitch (PS) are approximately 2 mm.

7. A medical device (10; 10*) according to any one of claims 2 to 6, A medical device characterized in that the width (w0; w0*) of each rotationally asymmetric groove (200A, 200B; 200A*, 200B*) is comprised between 0.5 mm and 1 mm.

8. A medical device (10; 10*) according to any one of claims 2 to 6, A medical device characterized in that the depth (d0*) of each rotationally asymmetric groove (200A, 200B; 200A*, 200B*) is comprised between 0.1 mm and 0.2 mm.

9. A medical device (10; 10*) according to any one of claims 2 to 6, A medical device characterized in that the depth of each of the rotationally asymmetric grooves (200A, 200B; 200A*, 200B*) is constant.

10. A medical device (10; 10*) according to any one of claims 2 to 6, A medical device characterized in that the depth of each rotationally asymmetric groove (200A, 200B; 200A*, 200B*) varies along the length of the rotationally asymmetric groove (200A, 200B; 200A*, 200B*).

11. A medical device (10; 10*) according to any one of claims 2 to 6, A medical device characterized in that the inner surface of each rotationally asymmetric groove (200A, 200B; 200A*, 200B*) is structured.

12. A medical device (10; 10*) according to any one of claims 1 to 6, the elongated rod member (100; 100*) is curved and / or bent substantially within a defined plane (P0), The medical device, characterized in that the first and second rotationally asymmetric markings (200A, 200B; 200A*, 200B*) are disposed along a curved section (100a) or an angled section (100b*) of the elongated rod member (100; 100*) proximate a distal end of the elongated rod member (100; 100*).

13. A medical device (10; 10*) according to claim 12, a distal end of the elongate rod member (100; 100*) comprising a tapered end (100A; 100A'; 100A''; 100A*; 100A**; 100A***) configured to function as a cutting device for cutting tissue; 1. A medical device comprising: a first surface and an opposite second surface, the first surface being inclined relative to the defined plane (P0); a second surface being concave relative to the defined plane (P0); and a second surface being concave relative to the defined plane (P0), the first surface being at least partially contoured and having a first inclined surface (SA; SA*) inclined relative to the defined plane (P0); and a second surface being concave relative to the defined plane (P0).

14. A medical device (10; 10*) for percutaneous open surgery, a handle portion (H; H*) designed to enable an operator to handle, orient and manipulate the medical instrument (10; 10*), and an elongated rod member (100; 100*) fixed to said handle portion (H; H*), the elongated rod member (100; 100*) extends from the handle portion (H; H*) to a distal end and is curved and / or bent substantially within a defined plane (P0); a distal end of the elongate rod member (100; 100*) comprising a tapered end (100A; 100A'; 100A''; 100A*; 100A**; 100A***) configured to function as a cutting device for cutting tissue; 1. A medical device comprising: a tapered end (100A; 100A'; 100A'; 100A*; 100A**; 100A***) of said elongate rod member (100; 100*) at least partially contoured by a first surface and an opposite second surface (SA, SB; SA*, SB*), i.e. a first inclined surface (SA; SA*) inclined with respect to said defined plane (P0) and a second concave surface (SB; SB*) substantially parallel to said defined plane (P0).

15. A medical device (10; 10*) according to claim 14, A medical device characterized in that the tapered end (100A; 100A'; 100A'; 100A*; 100A**; 100A***) of said elongated rod member (100; 100*) is further contoured by a pair of side surfaces (SC; SC*) forming lateral slopes laterally of at least a portion of said inclined surface (SA; SA*) and at least a portion of said concave surface (SB; SB*).

16. 16. The medical device (10; 10*) according to claim 15, A medical device characterized in that the inclination angle (δ; δ*) of each side surface (SC; SC*) relative to the concave surface (SB; SB*) is between 25° and 35°.

17. A medical device (10; 10*) according to any one of claims 14 to 16, A medical device characterized in that the inclination angle (γ; γ*) of a plane including the inclined surface (SA; SA*) relative to the defined plane (P0) is between 10° and 15°.

18. A medical device (100; 110) according to any one of claims 14 to 16, A medical device characterized in that the thickness (t; t+h; t*; t*+h*) of the tapered end (100A; 100A'; 100A''; 100A*; 100A**; 100A***) measured perpendicular to the defined plane (P0) does not exceed 1 mm.

19. A medical device (100; 110) according to any one of claims 14 to 16, A medical device characterized in that the width (w; w*) of said tapered end (100A; 100A'; 100A''; 100A*; 100A**; 100A***) measured in said defined plane (P0) does not exceed 2 mm.

20. A medical device (100; 110) according to any one of claims 14 to 16, 10. A medical device comprising: a tapered end portion (100A'; 100A''; 100A**; 100A***) comprising a longitudinal ridge (150'; 150''; 150**; 150***) projecting in a direction away from said concave surface (SB; SB*).

21. 21. The medical device (100; 110) according to claim 20, 10. A medical device characterized in that the height (h; h*) of said longitudinal ridges (150'; 150''; 150**; 150***), measured perpendicular to said defined plane (P0), does not exceed 0.5 mm.

22. 21. The medical device (100; 110) according to claim 20, A medical device characterized in that the leading edge of said longitudinal ridge (150'; 150''; 150**; 150***) is tapered and terminates short of the leading edge of said tapered end (100A'; 100A''; 100A**; 100A***).

23. The medical device (10; 10*) according to any one of claims 1 to 6 and 14 to 16, A medical device characterized in that the elongated rod member (100; 100*) extends along a generatrix (GX) and the lateral width of the elongated rod member (100; 100*) measured at any point along the generatrix (GX), including the distal end of the elongated rod member (100; 100*), does not exceed 2 mm.

24. The medical device (10; 10*) according to any one of claims 1 to 6 and 14 to 16, A medical device characterized in that the cross-sectional area of ​​said elongate rod member (100; 100*) does not exceed 2.5 mm2.

25. The medical device (10; 10*) according to any one of claims 1 to 6 and 14 to 16, A medical device characterized in that the elongated rod member (100; 100*) has a substantially circular or polygonal cross section upstream of the distal end of the elongated rod member (100; 100*) and its lateral width does not exceed 1.5 mm.

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