Surgical reamers and methods of reaming bone

Abstract

A surgical reamer and a method of reaming bone using a surgical reamer are provided. The reamer has a distal portion (10) including a proximal end (2) coupleable to a surgical rotary driver, a distal end (4), a rotational axis extending between the proximal end and the distal end, and a cutting surface between the proximal end and the distal end. The reamer also has a proximal portion (30) including a proximal end (32) coupleable to a surgical rotary driver, a distal end (34), a rotational axis extending between the proximal end and the distal end, a cutting surface between the proximal end and the distal end, and a cavity (50) extending proximally from the distal end (34) for receiving the proximal end (2) of the distal portion (10). An inner surface of the cavity is shaped to allow the proximal portion to tilt relative to the distal portion during rotation of the proximal portion.

Description

Background Technology

[0001] This specification relates to a surgical reamer and a method for reaming bone using a surgical reamer.

[0002] During revision hip surgery, a greater trochanteric lengthening osteotomy is used to allow removal of the well-fixed stem, bone cement, or broken prosthesis. Once the medullary canal has been cleared, the trochanter can be reattached using cerclage, and in the case of Wagner type prostheses, the medullary canal is enlarged to allow insertion of a new prosthesis.

[0003] The revision implant can be located in an area of ​​300 mm in length and 25 mm in diameter, so preparing the medullary canal without sacrificing the medial wall of the greater trochanter can be challenging and undesirable.

[0004] Similar considerations apply to shoulder surgery. Summary of the Invention

[0005] Aspects of this disclosure are shown in the appended independent and dependent claims. Combinations of features from the dependent claims may be appropriately combined with features of the independent claims, and not only as expressly shown in the claims.

[0006] According to one aspect of this disclosure, a surgical reamer is provided, the surgical reamer comprising:

[0007] The distal portion includes:

[0008] The proximal end is capable of being coupled to a surgical rotary actuator for applying torque to the distal portion;

[0009] distal end;

[0010] A rotation axis extending between the proximal end of the distal portion and the distal end of the distal portion; and

[0011] A cutting surface, the cutting surface being located between the proximal end of the distal portion and the distal end of the distal portion; and

[0012] The proximal portion includes:

[0013] The proximal end is connectable to a surgical rotary actuator for applying torque to the proximal portion;

[0014] distal end;

[0015] A rotation axis that extends between the proximal end of the proximal portion and the distal end of the proximal portion;

[0016] A cutting surface, the cutting surface being located between the proximal end of the proximal portion and the distal end of the proximal portion; and

[0017] A cavity extending proximally from the distal end of the proximal portion to receive the proximal end of the distal portion, wherein the inner surface of the cavity is shaped to allow the axis of rotation of the proximal portion to be inclined relative to the axis of rotation of the distal portion during rotation of the proximal portion about the axis of rotation of the proximal portion, wherein the proximal end of the distal portion is received within the cavity.

[0018] The surgical reamer according to embodiments of this disclosure facilitates a two-stage reaming process, wherein a distal portion is used to ream the internal surface of the bone (e.g., in the medullary canal), and then a proximal portion is mounted on the proximal end of the distal portion to ream into the bone at or near the opening, the distal portion being received in the bone. Mounting the proximal portion on the distal portion allows the proximal portion to be tilted relative to the distal portion, thereby enabling lateral reaming of characteristic features of the bone (e.g., the greater trochanter). In some embodiments, this may allow the reamed surface to conform to the shape of the implant to be placed within the bone.

[0019] The cavity can be shaped to allow the axis of rotation of the proximal portion to tilt relative to the axis of rotation of the distal portion in multiple directions during rotation of the proximal portion about its axis of rotation, wherein the proximal end of the distal portion is received within the cavity. This increases the additional flexibility for reaming the bone according to surgical procedures by providing multiple degrees of freedom for movement of the proximal portion.

[0020] The cavity can be shaped to allow the axis of rotation of the proximal portion to tilt so that the axis of rotation of the proximal portion precesses about the axis of rotation of the distal portion during rotation of the proximal portion about its own axis of rotation, wherein the proximal end of the distal portion is received within the cavity. This further increases the flexibility of reaming the bone according to the requirements of surgical procedures.

[0021] The cavity can be shaped to allow the axis of rotation of the proximal portion to tilt relative to the axis of rotation of the distal portion at an angle θ in the range of 0°≤θ≤25° during rotation of the proximal portion about the axis of rotation of the proximal portion, wherein the proximal end of the distal portion is received within the cavity.

[0022] The cavity can be truncated conical in shape. The narrow end of the truncated conical cavity can be located at the distal end of the proximal portion. The wide end of the truncated conical cavity can be positioned proximally relative to the distal end of the proximal portion. The cross-section of the truncated conical cavity in a plane perpendicular to the axis of rotation of the proximal portion can be substantially circular. These features provide multiple degrees of freedom for tilting of the proximal portion without inhibiting rotation of the proximal portion relative to the proximal end of the distal portion received within the cavity.

[0023] The proximal end of the distal portion can be slidably inserted into and removed from the cavity. This also allows for proximal / distal movement of the proximal portion during reaming and tilting.

[0024] The proximal end of the distal portion may have a connecting feature for attachment to a surgical rotary actuator. The cavity may have a depth equal to or greater than the length of the connecting feature. This allows the connecting feature to be fully received within the cavity. The size (length) of the proximal portion and the depth of the cavity can be selected based on the area of ​​bone that the cutting surface of the proximal portion needs to reach.

[0025] The distal end of the proximal portion may have a ramp to promote the inclination of the proximal portion relative to the distal portion.

[0026] The chamfer of the inclined plane relative to the plane perpendicular to the axis of rotation of the proximal portion can be substantially equal to or greater than the maximum value of the tilt angle θ allowed by the shape of the cavity.

[0027] The cutting surface of the proximal portion may extend between the distal end of the proximal portion and a cutting shoulder located between the distal end of the proximal portion and the proximal end of the proximal portion. The shoulder may facilitate retrograde enlargement of the greater trochanter. For example, the shoulder may be shaped to match the contour of the site (e.g., the shoulder) of an implant to be placed in the bone according to surgical procedures.

[0028] The proximal end of the proximal portion can be narrower than the cutting surface at the cutting shoulder.

[0029] The cutting surface of the proximal portion can be formed on the distal shaft portion of the proximal portion. The distal shaft portion can be tapered, so that it has a wider diameter at the distal end of the distal shaft portion than at the proximal end of the distal shaft portion.

[0030] The widest diameter of the cutting surface of the proximal portion at the distal end of the proximal portion can be substantially equal to the widest diameter of the cutting surface of the distal portion. This provides space for attaching the proximal end of the proximal portion to a surgical rotary actuator.

[0031] In some embodiments, the distal portion may be elongated to enlarge the inner surface of the medullary canal of the femur. The proximal portion is elongated to enlarge the inner surface of the greater trochanter of the femur. In some embodiments, the distal portion may be elongated to enlarge the inner surface of the medullary canal of the humerus. The proximal portion is elongated to enlarge the inner surface of the greater trochanter of the humerus.

[0032] According to another aspect of this disclosure, a surgical kit is provided, the surgical kit comprising a surgical reamer according to any one of claims 1 to 14.

[0033] According to another aspect of this disclosure, a method for enlarging bone using a surgical reamer is provided, the method comprising:

[0034] The inner surface of the bone is enlarged using the distal portion of a surgical reamer, wherein the distal portion...

[0035] Parts include:

[0036] The proximal end is capable of being coupled to a surgical rotary actuator for applying torque to the distal portion;

[0037] distal end;

[0038] A rotation axis extending between the proximal end of the distal portion and the distal end of the distal portion; and

[0039] A cutting surface, the cutting surface being located between the proximal end of the distal portion and the distal end of the distal portion; and

[0040] The inner surface of the bone is enlarged using the proximal portion of a surgical reamer, wherein the proximal portion...

[0041] Parts include:

[0042] The proximal end is connectable to a surgical rotary actuator for applying torque to the proximal portion;

[0043] distal end;

[0044] A rotation axis that extends between the proximal end of the proximal portion and the distal end of the proximal portion;

[0045] A cutting surface, the cutting surface being located between the proximal end of the proximal portion and the distal end of the proximal portion; and

[0046] A cavity extending proximally from the distal end of the proximal portion to receive the proximal end of the distal portion, wherein the inner surface of the cavity is shaped to allow the axis of rotation of the proximal portion to be inclined relative to the axis of rotation of the distal portion during rotation of the proximal portion about the axis of rotation of the proximal portion, wherein the proximal end of the distal portion is received within the cavity.

[0047] Enlarging the inner surface of bone using the proximal portion of a surgical reamer includes: tilting the axis of rotation of the proximal portion relative to the axis of rotation of the distal portion during rotation of the proximal portion about the axis of rotation of the proximal portion, wherein the proximal end of the distal portion is received within the cavity.

[0048] The method according to embodiments of this disclosure provides a two-stage enlargement process, wherein a distal portion is used to enlarge the internal surface of the bone (e.g., in the medullary canal), and then a proximal portion is mounted on the proximal end of the distal portion to enlarge the bone into the bone at or near the opening, the distal portion being received in the bone. The tilt of the proximal portion relative to the distal portion allows for lateral enlargement of characteristic portions of the bone (e.g., the greater trochanter). In some embodiments, this allows the enlarged surface to match the shape of the implant to be placed within the bone.

[0049] While the proximal portion is used to enlarge the inner surface of the bone, the distal portion can remain essentially stationary within the bone.

[0050] The method may include:

[0051] Connect the surgical rotary actuator to the proximal end of the distal portion;

[0052] Enlarging is performed on the inner surface of the bone using the distal portion;

[0053] Disengage the surgical rotary actuator from the proximal end of the distal portion;

[0054] Connect the surgical rotary actuator to the proximal end of the proximal portion;

[0055] While retaining the distal portion within the bone, the proximal end of the distal portion is received within the cavity; and

[0056] The proximal portion is used to enlarge the inner surface of the bone.

[0057] The method may include: tilting the axis of rotation of the proximal portion relative to the axis of rotation of the distal portion in multiple directions during rotation of the proximal portion about the axis of rotation of the proximal portion, wherein the proximal end of the distal portion is received within the cavity.

[0058] The method may include: manually precessing the axis of rotation of the proximal portion about the axis of rotation of the distal portion during rotation of the proximal portion about the axis of rotation of the distal portion, wherein the proximal end of the distal portion is received within the cavity.

[0059] The method may include: enlarging the bone using a cutting shoulder of the cutting surface of the proximal portion to substantially match the shape of the shoulder portion of the implant to be installed in the bone.

[0060] The method may include: tilting the axis of rotation of the proximal portion at an angle θ in the range of 0°≤θ≤25° relative to the axis of rotation of the distal portion during rotation of the proximal portion about the axis of rotation of the proximal portion, wherein the proximal end of the distal portion is received within the cavity.

[0061] The method may include: slidably inserting the proximal end of the distal portion into the cavity / removing the proximal end of the distal portion from the cavity.

[0062] In some embodiments, the bone may be the femur. Enlarging the inner surface of the bone using the distal portion may include enlarging the inner surface of the medullary canal of the femur. Enlarging the inner surface of the bone using the proximal portion may include enlarging the inner surface of the greater trochanter of the femur.

[0063] In some embodiments, the bone may be the humerus. Enlarging the inner surface of the bone using the distal portion may include enlarging the inner surface of the medullary canal of the humerus. Enlarging the inner surface of the bone using the proximal portion may include enlarging the inner surface of the greater trochanter of the humerus. Attached Figure Description

[0064] Embodiments of this disclosure will be described below by way of example only with reference to the accompanying drawings, wherein similar reference numerals are associated with similar elements, and in the drawings:

[0065] Figure 1 The implant was shown;

[0066] Figure 2 The distal portion of a surgical reamer according to an embodiment of the present disclosure is shown;

[0067] Figure 3 It shows Figure 2 The cross-section of the distal portion of the surgical reamer;

[0068] Figure 4 The proximal portion of a surgical reamer according to an embodiment of the present invention is shown;

[0069] Figure 5 It shows Figure 2 The cross-section of the proximal portion of the surgical reamer;

[0070] Figure 6 A cross-section of an assembled surgical reamer according to an embodiment of the present disclosure is shown, the assembled surgical reamer comprising... Figures 2 to 3 The distal part and Figures 4 to 5 The proximal part; and

[0071] Figure 7 The use of embodiments according to this disclosure is illustrated. Figures 2 to 6 The method of enlarging holes in bone using a surgical reamer. Detailed Implementation

[0072] The embodiments of this disclosure are described below with reference to the accompanying drawings.

[0073] The embodiments described below relate to a surgical reamer and a method for use in hip surgery. However, it is contemplated that the surgical reamer and method according to embodiments of this disclosure could be used in shoulder surgery.

[0074] Figure 1 Implant 20 is shown. Implant 20 is intended for use in hip replacement procedures. Implant 20 includes an elongated stem 26 that tapers to a distal tip 28. The stem 26 is shaped to be received within the medullary canal of the femur, for example, as part of a hip revision surgery. The length of the stem 26 is... Figure 1 The designation is "F". Implant 20 also includes a neck portion 22 that extends at an angle to the proximal end of the stem portion 26. Implant 20 may also include a shoulder portion 24 positioned adjacent to the base of the neck portion 22. The proximal end of the neck portion 22 is configured to attach to the head portion for insertion into the patient's acetabulum. Implant 20 may be an experimental implant for use in hip revision surgery, or may include a final implant to be installed in a patient. As described above, embodiments of this disclosure are envisioned for use in shoulder surgery involving implants of similar types.

[0075] To prepare the patient's femur for implantation 20, the medullary canal must be accessed, and bone must then be removed from within the canal to create a suitable cavity to receive the stem 26. In revision hip surgery where a new stem replaces the previous implant, a procedure known as greater trochanteric osteotomy can be used. Greater trochanteric osteotomy involves removing the stem of the previous implant, along with any bone cement, from the medullary canal. Once the medullary canal has been cleared, the trochanter of the femur can be reattached using cerclage, and in the case of Wagner-type prostheses, the medullary canal is enlarged to allow for the removal of any further bone, which is necessary to create a suitable cavity to receive the new implant. Similar considerations can be applied to shoulder surgery. Embodiments of this disclosure relate to a surgical reamer and a method for performing this task.

[0076] Figures 2 to 6Various views of a surgical reamer according to embodiments of the present disclosure are shown. Specifically, Figure 2 The distal portion 10 of the surgical reamer is shown. Figure 3 A cross-section of the distal portion 10 is shown. Figure 4 The proximal portion 30 of the surgical reamer is shown. Figure 5 A cross-section of the proximal portion 30 is shown, and Figure 6 A cross-section of an assembled surgical reamer is shown, which includes a distal portion 10 and a proximal portion 30 joined together. Figure 7 The use of embodiments according to this disclosure is illustrated. Figures 2 to 6 The method of enlarging the femur with a surgical reamer.

[0077] The distal portion 10 has a proximal end 2. The proximal end 2 is connectable to a surgical rotary actuator for applying torque to the distal portion 10. In this embodiment, the proximal end 2 includes a substantially cylindrical shaft that can be inserted into the surgical rotary actuator for connecting the distal portion 10 to the actuator. Contemplate that the proximal end 2 of the distal portion 10 may include any suitable connection features for achieving the connection between the distal portion 10 and the actuator. As will be described in more detail below, the proximal end 2 may also be used to connect the distal portion 10 of a surgical reamer to the proximal portion 30.

[0078] In use, applying torque to the distal portion 10 via a surgical rotary actuator causes the distal portion 10 to rotate, allowing the distal portion 10 to act as a drill / reamer to remove bone cement and / or bone from the femur (or from the humerus in the case of shoulder surgery) as part of a greater trochanter lengthening osteotomy.

[0079] The distal portion 10 also has a distal end 4. In this embodiment, the tapered shaft 6 extends along the rotation axis 14 of the distal portion 10 at the proximal end 2 (e.g., as shown in the figure). Figure 2 and Figure 3 As shown, the tapered shaft 6 extends between the distal end of the substantially cylindrical shaft forming the proximal end 2 and the distal end 4. The tapered shaft 6 tapers inward toward the distal end 4, such that the distal end forms the tip of the distal portion 10. The tapered shaft 6 may have a substantially circular cross-section in a plane perpendicular to the axis of rotation 14 of the distal portion 10.

[0080] The distal portion 10 also includes a cutting surface 12 located between the proximal end 2 and the distal end 4 of the distal portion 10. In this embodiment, the cutting surface 12 includes the outer surface of the tapered shaft 6. The surface of the tapered shaft may include any suitable surface features for realizing the cutting surface 12. In this embodiment, the cutting surface 12 includes a plurality of generally helical grooves 13 extending from the proximal shoulder 8 of the tapered shaft 6 toward the distal end 4.

[0081] In this implementation scheme, Figure 2 and Figure 3 This indicates multiple dimensions associated with the distal portion 10.

[0082] Specifically, in this implementation plan:

[0083] φB1 represents the diameter of the shoulder 8 located at the proximal end of the tapered shaft 6 (i.e., the diameter of the tapered shaft 6 at its widest part);

[0084] •E represents the length of the tapered shaft 6 between the shoulder 8 and the distal end 4; and

[0085] φB2 represents the diameter of the substantially cylindrical shaft that forms the proximal end 2 of the distal portion 10.

[0086] Now turning Figure 4 and Figure 5 The proximal portion 30 of the surgical reamer has a proximal end 32 and a distal end 34. Like the proximal end 2 of the distal portion, the proximal end 32 of the proximal portion 30 is engageable with a surgical rotary actuator for applying torque to the proximal portion 30. In this embodiment, the proximal end 32 includes a substantially cylindrical shaft that can be inserted into the surgical rotary actuator for engaging the distal portion 10 to the actuator. It is contemplated that the proximal end 32 of the proximal portion 30 may include any suitable connection features for achieving engagement between the proximal portion 30 and the actuator. For example, in this embodiment, a flange is located at the proximal end of the substantially cylindrical shaft forming the proximal end 32.

[0087] In use, applying torque to the proximal portion 30 via a surgical rotary actuator causes the proximal portion 30 to rotate, allowing it to act as a reamer to remove bone cement and / or bone from the femur (or, in the case of shoulder surgery, from the humerus) as part of a greater trochanter lengthening osteotomy. This will be described in more detail below.

[0088] The proximal portion 30 has a rotation axis 44 that extends between the proximal end 32 and the distal end 34 of the proximal portion 30. In this embodiment, the shaft 36 / 46 extends along the rotation axis 44 at the proximal end 32 (e.g., as shown in the image). Figure 4 and Figure 5As shown, the shaft 36 / 46 extends between the distal end (of the substantially cylindrical shaft forming the proximal end 32) and the distal end 34. The shaft 36 / 46 may have a substantially circular cross-section in a plane perpendicular to the axis of rotation 44 of the proximal portion 30. In this embodiment, the shaft 36 / 46 includes a distal shaft portion 36 and a proximal shaft portion 46. In some embodiments, the proximal shaft portion 46 may be omitted. The proximal shaft portion 46 may have a substantially smooth outer surface and may be used to provide a working distance between the proximal end 32 attached to the drive and the cutting surface 42 to be described below.

[0089] The proximal portion 30 also includes a cutting surface 42 located between the proximal end 32 and the distal end 34 of the proximal portion 30. In this embodiment, the cutting surface 12 is located on the outer surface of the distal shaft portion 36. The surface of the distal shaft portion 36 may include any suitable surface features for realizing the cutting surface 42. In this embodiment, the cutting surface 42 includes a plurality of generally helical grooves 33 extending from the proximal cutting shoulder 38 of the distal shaft portion 36 toward the distal end 34. In this embodiment, the proximal shoulder 38 is located at the interface between the proximal shaft portion 46 and the distal shaft portion 36, and is positioned adjacent to the proximal end 32 in embodiments where the proximal shaft portion 46 is omitted. Relative to the proximal cutting shoulder 38, the features of the proximal portion 30, including the proximal end and the proximal shaft portion 46 (if present), may be narrower than the cutting surface 42 at the proximal cutting shoulder 38, such that they do not impede the use of the proximal cutting shoulder 38.

[0090] The proximal portion 30 also includes a cavity 50. The cavity 50 extends proximally from the distal end 34 of the proximal portion 30. The cavity is shaped and sized to receive the proximal end 2 of the distal portion 10. Specifically, the inner surface of the cavity 50 is shaped to allow the axis of rotation 44 of the proximal portion 30 to tilt relative to the axis of rotation 14 of the distal portion 10 during rotation of the proximal portion 30 about the axis of rotation 44 of the proximal portion 30, wherein the proximal end 2 of the distal portion 10 is received within the cavity 50. The depth of the cavity 50 can be selected such that the proximal end 2 of the distal portion 10 can be completely received within the cavity 50.

[0091] In this embodiment, the cavity 50 is truncated conical, but it should be understood that this is not necessary, and other shapes may allow the aforementioned tilt of the proximal portion 30 relative to the distal portion 10. The narrow end of the truncated conical cavity 50 is located at the distal end 34 of the proximal portion 30, and the wide end of the truncated conical cavity 50 is positioned proximally relative to the distal end 34 of the proximal portion 30. In this embodiment, the truncated conical cavity 50 has a substantially circular cross-section in a plane perpendicular to the axis of rotation 44. As will be described in more detail below, the cavity 50 with this internal shape allows the proximal portion 30 to tilt and then precess about the axis of rotation 14 of the distal portion 10 while the proximal end 2 of the distal portion 10 is received within the cavity 50. The cone angle of the truncated conical cavity 50 may be selected to determine the maximum tilt angle of the proximal portion 30.

[0092] In this implementation scheme, Figure 4 and Figure 5 This indicates multiple dimensions and angles associated with the proximal portion 30. Specifically:

[0093] φB3 represents the diameter of the distal shaft portion 36;

[0094] ○ In some embodiments, the diameter of the distal shaft portion 36 of the proximal portion 30 may be selected to be close to or match the diameter of the tapered shaft 6 at its widest part (i.e., φB3≈φB1);

[0095] •C represents the length of the distal shaft portion 36 between the proximal shoulder 38 and the distal end 34;

[0096] φB4 represents the diameter of the opening of cavity 50 located at the distal end 34 of proximal portion 30. In some embodiments, this diameter may be selected to match the diameter of the substantially cylindrical shaft forming proximal end 2 of distal portion 10, plus a tolerance, i.e., φB4 ≈ φB2; and

[0097] • G represents the cone angle between the inner wall 52 of the cavity 50 and the axis of rotation 44. In this embodiment, it should be noted that the inclination angle θ of the proximal portion 30 of the proximal end 2 abutting the side wall 52 of the cavity 50 is equal to G at the maximum inclination (see [link to relevant documentation]). Figure 6 In some implementations, 0° ≤ G ≤ 25° (and therefore the maximum value of the tilt angle θ is also in the range 0° ≤ θ ≤ 25°).

[0098] (within 25°).

[0099] Conversely, in some embodiments, the distal shaft portion 36 may be tapered. Specifically, the distal shaft portion 36 may taper so that it is narrower proximally and wider distally, thus forming a reverse-tapered configuration. In such embodiments, the combination of the taper angle of the distal shaft portion 36 and the G value will allow for the expansion of the tapered cavity while providing sufficient clearance with the rotor. By way of example only, by using an angle G of 22.5° and a “reverse” taper angle of 20° for the distal shaft portion 36, a 2.5-degree tapered cavity can be expanded, thereby providing sufficient clearance with the rotor simultaneously.

[0100] Now turning Figure 6 The connection between the distal portion 10 and the proximal portion 30 of the surgical reamer will be described in more detail.

[0101] As in Figure 6 As can be seen, the proximal portion 30 can be connected to the distal portion 10 by inserting the proximal end 2 of the distal portion 10 into the cavity 50 of the proximal portion 30. The proximal end 2 can be slidably inserted into the cavity 50. With the proximal end 2 received within the cavity 50, the surgeon can manipulate the proximal portion to change the tilt angle θ between the proximal portion 30 and the distal portion 10. Figure 6 The diagram shows the proximal portion 30 tilted at a maximum tilt angle θ = G, such that the proximal end 2 abuts against the inner wall 52 of the cavity 50, and the distance D between the distal end 34 of the proximal portion 30 and the proximal shoulder 8 of the distal portion 10 is changed. It should be noted that for a small tilt angle θ, the vertical “height” of the cutting surface 42 of the distal shaft portion 36 along the axis of rotation 14 is given by C.cos(θ)≈C.

[0102] These operations can be performed simultaneously with applying torque to the proximal portion 30 to rotate the proximal portion relative to the distal portion 10. This allows the surgeon to use the cutting surface 42 of the proximal portion 30 as a guide while using the connection between the proximal end 2 of the distal portion 10 and the cavity 50 of the proximal portion 30 to perform lateral reaming of the femur (or, in the case of shoulder surgery, the humerus). It should be noted that, in use, according to the embodiments of this disclosure, there is substantially no torque transmission between the proximal portion 30 and the distal portion 10, and the distal portion 10 generally remains stationary during rotation of the proximal portion 30. Providing a substantially cylindrical proximal end 2 and a truncated conical cavity 50 provides a smooth connection between the distal portion 10 and the proximal portion 30 to help prevent accidental torque transmission in practice.

[0103] Return to temporarily Figure 1 In some implementations, the combined length of the distal shaft portion 36 and the tapered shaft 6, plus a typical value for distance D during the specification, can be selected to approximate or match the length F of the handle portion 26 (i.e., E+C+D≈F).

[0104] Go to Figure 7 The use of embodiments according to this disclosure will now be described. Figures 2 to 6 A method for enlarging the femur 60 using a surgical reamer. As described above, it is envisioned that this method could also be applied to shoulder surgery involving enlarging the humerus.

[0105] In the initial step, the distal portion 10 may be attached to a surgical rotation actuator and then used to perform initial reaming of the femur 60 (or the humerus in the case of shoulder surgery). This reaming may involve removing bone from the medullary canal 70 of the femur 60 (or the humerus in the case of shoulder surgery), which typically involves inserting the distal portion 10 into the medullary canal 60, such as... Figure 7 As shown, the distal portion 10 is manipulated while torque is applied to it. In some embodiments, the taper angle of the tapered shaft 6 may approximate or match... Figure 1 The tapered angle of the elongated stem 26 of the implant 20 of the type shown helps to shape the inner cone of the medullary cavity 70 to receive the implant 20. Once this reaming step has been performed, the surgical rotary actuator can be disconnected from the distal portion 10, while the distal portion remains within the medullary cavity 60.

[0106] In the next step, the proximal portion 30 may be coupled to a surgical rotary actuator (which may be the same surgical rotary actuator used to rotate the distal portion 10 in the initial reaming step described above, or may not be the same surgical rotary actuator), and coupled to the distal portion 10 by placing the proximal portion into the medullary canal so that the proximal end 2 is received within the cavity 50. Torque can then be applied to the proximal portion 30 to ream the bone from the femur 60 (or from the humerus in the case of shoulder surgery) while the surgeon manipulates the proximal portion 30. These operations may include one or more of the following:

[0107] • Move the proximal portion along the rotation axis 14 parallel to the distal portion 10 to change the vertical position of the proximal portion 30 within the femur 60 (or, in the case of shoulder surgery, the humerus), such as Figure 7 The middle part is indicated by an arrow marked with an H;

[0108] • Tilt the proximal portion 30 in one or more directions such that the axis of rotation 44 of the proximal portion 30 is tilted relative to the axis of rotation 14 of the distal portion 10; and

[0109] • Cause the proximal portion 30 to precess about the rotation axis 14 of the distal portion 10, as if by Figure 7 The arrow marked with K indicates ( Figure 7 The arrow marked with J indicates the rotation of the proximal portion 30 around its own axis of rotation 44.

[0110] In some embodiments, a portion of the cutting surface 36 located near the shoulder 38 of the proximal portion 30 can be used to remove the surface 66 of the greater trochanter 62 of the femur 60 (or, in the case of shoulder surgery), such as... Figure 7 As shown in the diagram. Shoulder 38 can facilitate reverse reaming of the large rotor. For example, shoulder 36 can have a close or matching shape. Figure 1 The outline of the shoulder portion 24 of the implant 20 of the type shown is used to facilitate the preparation of a bone surface for receiving the implant 20. The inner surface (e.g., the sidewall 52 of the cavity 50) may be shaped such that the maximum tilt angle of the proximal portion 30 relative to the distal portion 10 prevents over-enlargement of, for example, the greater trochanter 62 during this step.

[0111] Once the reaming is complete, the proximal portion 30 can be disengaged from the distal portion 10 by withdrawing the proximal portion from the femur 60 (or from the humerus in the case of shoulder surgery). The distal portion 10 can then be removed from the femur 60 (or from the humerus in the case of shoulder surgery), and the procedure can proceed to inserting the implant into the femur 60 (or the humerus in the case of shoulder surgery).

[0112] Return to Figure 5 In some embodiments, the distal end 34 of the proximal portion 30 may be provided with a beveled portion 35. This beveled portion 35 may taper outwards such that, as the distal axis portion 36 moves from the distal end 34 toward the proximal end, the diameter of the distal axis portion 36 increases from the opening of the cavity to a diameter φB3. The beveled portion 35 may facilitate the tilting of the proximal portion 30 relative to the distal portion 10. The taper angle of the beveled portion 35 (measured between the surface of the beveled portion 35 and a plane perpendicular to the axis of rotation 44) may, for example, be substantially equal to or greater than angle G, to allow the maximum tilting of the proximal portion 30 to be achieved without the surface of the beveled portion 35 of the distal end 34 contacting the proximal shoulder 8 of the distal portion 10. This prevents unintentional movement of the proximal portion 30 along the axis of rotation 14 of the distal portion 10 due to the distal end 34 of the proximal portion 30 resting on the proximal shoulder 8 of the distal portion 10 when the proximal portion 30 is tilted.

[0113] The type of surgical reamer described herein may be included in a surgical kit.

[0114] Therefore, a surgical reamer and a method for reaming bone using the surgical reamer have been described. The reamer has a distal portion including a proximal end capable of being coupled to a surgical rotary actuator; a distal end; a rotation axis extending between the proximal and distal ends; and a cutting surface located between the proximal and distal ends. The reamer also has a proximal portion including a proximal end capable of being coupled to a surgical rotary actuator; a distal end; a rotation axis extending between the proximal and distal ends; a cutting surface located between the proximal and distal ends; and a cavity extending proximally from the distal end to receive the proximal end of the distal portion. The inner surface of the cavity is shaped to allow the proximal portion to tilt relative to the distal portion during rotation of the proximal portion.

[0115] Although specific embodiments of this disclosure have been described, it should be understood that many modifications / additions and / or substitutions may be made within the scope of the claims.

Claims

1. A surgical reamer, comprising: The distal portion includes: The proximal end is capable of being coupled to a surgical rotary actuator for applying torque to the distal portion; distal end; A rotation axis extending between the proximal end of the distal portion and the distal end of the distal portion; and A cutting surface, the cutting surface being located between the proximal end of the distal portion and the distal end of the distal portion; and The proximal portion includes: The proximal end is connectable to a surgical rotary actuator for applying torque to the proximal portion; distal end; A rotation axis that extends between the proximal end of the proximal portion and the distal end of the proximal portion; A cutting surface, the cutting surface being located between the proximal end of the proximal portion and the distal end of the proximal portion; and A cavity extending proximally from the distal end of the proximal portion to receive the proximal end of the distal portion, wherein: The inner surface of the cavity is shaped to allow the axis of rotation of the proximal portion to be inclined relative to the axis of rotation of the distal portion during rotation of the proximal portion about the axis of rotation of the proximal portion, wherein the proximal end of the distal portion is received within the cavity. The cavity is truncated cone-shaped. The narrow end of the truncated cone-shaped cavity is located at the distal end of the proximal portion, and The wide end of the truncated cone-shaped cavity is positioned proximally relative to the distal end of the proximal portion.

2. The surgical reamer of claim 1, wherein the cavity is shaped to allow the axis of rotation of the proximal portion to be tilted relative to the axis of rotation of the distal portion in multiple directions during rotation of the proximal portion about the axis of rotation of the proximal portion, wherein the proximal end of the distal portion is received within the cavity.

3. The surgical reamer of claim 2, wherein the cavity is shaped to allow the axis of rotation of the proximal portion to tilt so that the axis of rotation of the proximal portion precesses about the axis of rotation of the distal portion during rotation of the proximal portion about the axis of rotation of the proximal portion, wherein the proximal end of the distal portion is received within the cavity.

4. The surgical reamer according to any one of claims 1-3, wherein the cavity is shaped to allow the axis of rotation of the proximal portion to be tilted relative to the axis of rotation of the distal portion at an angle θ in the range of 0° ≤ θ ≤ 25° during rotation of the proximal portion about the axis of rotation of the proximal portion, wherein the proximal end of the distal portion is received within the cavity.

5. The surgical reamer according to any one of claims 1-3, wherein the cross-section of the truncated cone-shaped cavity in a plane perpendicular to the axis of rotation of the proximal portion is substantially circular.

6. The surgical reamer according to any one of claims 1-3, wherein the proximal end of the distal portion is slidably inserted and removable from the cavity.

7. The surgical reamer according to any one of claims 1-3, wherein the proximal end of the distal portion includes a connecting feature for engagement with the surgical rotary actuator, and wherein the cavity has a depth equal to or greater than the length of the connecting feature for fully receiving the connecting feature within the cavity.

8. The surgical reamer of claim 4, wherein the distal end of the proximal portion includes a bevel for promoting the inclination of the proximal portion relative to the distal portion.

9. The surgical reamer of claim 8, wherein the chamfer of the bevel relative to the plane perpendicular to the axis of rotation of the proximal portion is substantially equal to or greater than the maximum value of the tilt angle θ allowed by the shape of the cavity.

10. The surgical reamer according to any one of claims 1-3, wherein the cutting surface of the proximal portion extends between the distal end of the proximal portion and a cutting shoulder located between the distal end of the proximal portion and the proximal end of the proximal portion.

11. The surgical reamer according to any one of claims 1-3, wherein the cutting surface of the proximal portion is formed on the distal axial portion of the proximal portion, and wherein the distal axial portion is tapered to have a wider diameter at the distal end of the distal axial portion than at the proximal end of the distal axial portion.

12. The surgical reamer of claim 10, wherein the widest diameter of the cutting surface of the proximal portion at the distal end of the proximal portion is substantially equal to the widest diameter of the cutting surface of the distal portion.

13. The surgical reamer according to any one of claims 1-3, wherein: The distal portion is elongated to enlarge the inner surface of the medullary canal of the femur, and the proximal portion is elongated to enlarge the inner surface of the greater trochanter of the femur. or The distal portion is elongated to enlarge the inner surface of the medullary canal of the humerus, and the proximal portion is elongated to enlarge the inner surface of the greater trochanter of the humerus.

14. A surgical kit comprising a surgical reamer according to any of the preceding claims.

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