Surgical saw

Abstract

The invention discloses a surgical saw, comprising: a saw head comprising a collet having an opening configured to receive a movable blade; wherein the blade is detachably connected in the chuck; the handheld piece is connected to the saw head, and the handheld piece is provided with a driving mechanism; and wherein the drive mechanism moves the blade.

Description

[0001] This application is a divisional application of the application with the filing date of March 5, 2019, application number 201980017429.2 (international application number PCT / US2019 / 020677), and invention title "Sheathed Surgical Saw Blade with Bearings".

[0002] Cross - Reference to Related Applications

[0003] This application claims the benefit of priority of U.S. Provisional Patent Application Serial No. 62 / 639,040, filed on March 6, 2018, with the title "Sheathed Surgical Saw Blade and Bearings" and U.S. Provisional Patent Application Serial No. 62 / 724,914, filed on August 30, 2018, with the title "Sheathed Surgical Saw Blade with Bearings and Universal Saw Handpiece for Sheathed and Standard Blades", the entire disclosures of which are incorporated herein by reference. Technical Field

[0004] The present invention generally relates to surgical blade assemblies, and more particularly to sheathed blade assemblies having a void volume between an outer sheath and an inner blade to minimize wear. Background Art

[0005] Sheathed surgical blades include a moving inner member (the blade) and an outer stationary member (the sheath). During use, contact between the moving and stationary members is inevitable due to the application of cantilever forces to the assembly. Due to the high linear speed of the blade, when the blade contacts the stationary sheath, the assembly gets very hot and wears. The heating of the sheath and the blade can lead to osteonecrosis and injury to the patient or user. In addition, the wear generated by the blade contacting the sheath will produce metal particles that may fall into the surgical site.

[0006] By design, sheathed blade assemblies and non - sheathed (standard) blades require different mechanisms to dock with a surgical saw handpiece, and thus different handpieces are needed to drive one or the other blade. The need for two different saw handpieces (one to drive a sheathed blade assembly and one to drive a non - sheathed blade) adds additional cost to a surgical facility and / or requires a choice of one blade option (sheathed or non - sheathed).

[0007] Accordingly, there is a need for a single surgical saw handpiece for driving a sheathed blade assembly as well as an unsheathed (standard) blade and a sheathed blade assembly that prevents or minimizes potential contact between a moving internal blade and the sheath.

[0008] Disclaimer for the related art section description: With respect to the specific patents / published works / products described in the related art section above or elsewhere in this disclosure, these discussions should not be construed as an admission that the patents / published works / products discussed are prior art for purposes of patent law. For example, some or all of the patents / published works / products discussed may not be early enough in time, may not reflect subject matter that has developed early enough in time, and / or may not be sufficient to constitute prior art for purposes equivalent to patent law. With respect to the specific patents / published works / products described in the related art section above and / or discussed throughout the application, their descriptions / disclosures are hereby incorporated by reference in their entireties. Summary of the Invention

[0009] The present invention relates to a single surgical saw that will drive a sheathed blade assembly as well as an unsheathed (standard) blade and a sheathed blade that prevents potential contact between a moving internal blade and an external sheath. According to one aspect, the sheathed blade assembly includes: an external sheath having a top portion and a bottom portion with a lumen therebetween; an internal blade movable within the lumen of the external sheath; and at least one ball bearing within the lumen of the external sheath. The ball bearing creates a void volume between the internal blade and at least one of the top portion and the bottom portion of the external sheath.

[0010] According to another aspect, the sheathed blade assembly includes: an external sheath having a first portion and a second portion with a lumen therebetween; an internal blade movable within the lumen of the external sheath; a first pit within a first surface of the internal blade; and a first ball bearing within the first pit. The first ball bearing creates a void volume between the first surface of the internal blade and the first portion of the external sheath.

[0011] According to another aspect, the present invention is a surgical saw. The surgical saw includes a saw head that includes a chuck having an opening configured to receive a movable blade. The blade is removably coupled within the chuck. A handpiece is connected to the saw head and the handpiece has a drive mechanism to move the blade.

[0012] These and other aspects of the invention will become apparent and be elucidated in connection with the embodiments described below. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] One or more aspects of the invention are specifically pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other objects, features, and advantages of the invention will become apparent from the following description in conjunction with the accompanying drawings, in which:

[0014] Figure 1 is a top perspective schematic view of a sheathed blade assembly according to one embodiment;

[0015] Figure 2 is an exploded perspective schematic view of a sheathed blade assembly according to one embodiment;

[0016] Figure 3 is a distal schematic view of a sheathed blade assembly according to one embodiment;

[0017] Figure 4 is a side schematic view of a sheathed blade assembly according to one embodiment;

[0018] Figure 5 is a top perspective schematic view of a sheathed blade assembly according to an alternative embodiment;

[0019] Figure 6 is an exploded perspective schematic view of a sheathed blade assembly according to an alternative embodiment;

[0020] Figure 7 is a side perspective schematic view of a general saw head according to one embodiment;

[0021] Figure 8 is a side perspective schematic view of a sheathed blade assembly connected to a general saw head according to one embodiment;

[0022] Figure 9 is a side perspective schematic view of a bladeless blade connected to a general saw head according to an alternative embodiment; and

[0023] Figure 10 is connected to Figure 8 an exploded schematic view of a sheathed blade assembly of a general saw head. DETAILED DESCRIPTION

[0024] Aspects of the present invention and certain of its features, advantages, and details are explained more fully below with reference to the non-limiting examples shown in the accompanying drawings. Descriptions of well-known structures are omitted so as not to unnecessarily obscure the present invention in detail. However, it should be understood that the detailed descriptions and the specific non-limiting examples, while indicating aspects of the present invention, are given by way of illustration only and not by way of limitation. Various substitutions, modifications, additions, and / or arrangements within the spirit and / or scope of the basic concepts of the present disclosure will be apparent to those skilled in the art.

[0025] Referring now to the drawings, in which like reference numerals always refer to like parts, Figure 1 a top perspective schematic view of a sheathed blade assembly 100 according to one embodiment is shown. The sheathed blade assembly 100 extends from a proximal end 102 to a distal end 104. As shown in the depicted embodiment, the sheathed blade assembly 100 includes a fixed outer sheath 106 and a movable inner blade 108 extending from the fixed outer sheath.

[0026] Turning now to Figure 2 , an exploded perspective schematic view of the sheathed blade assembly 100 according to one embodiment is shown. In the depicted embodiment, the sheathed blade assembly 100 includes an outer sheath 106 having two parts, a top part 110 and a bottom part 112. The top part 110 and the bottom part 112 are made of a metal such as stainless steel. As Figure 2 shown, the top part 110 is an elongated rectangular plate. In the depicted embodiment, the top part 110 has a straight proximal edge 114 and a curved distal edge 116. The bottom part 112 is also an elongated rectangular plate having a straight proximal edge 118 and a curved distal edge 120. The distal end 122 of the bottom part 112 further includes a circular hole 124. In the depicted embodiment, the distal end 122 of the bottom part 112 includes a pair of arms 126 (or tips) extending therefrom. The arms 126 extend towards each other but do not intersect, thereby forming a gap 128 therebetween. The gap 128 extends into the circular hole 124, as shown.

[0027] Still referring to Figure 2 , the outer sheath 106 further includes a track 130 extending along the bottom part 112 between the straight proximal edge 118 and the curved distal edge 120. The track 130 defines a lumen 132 within the sheathed blade assembly 100 between the top part 110 and the bottom part 112 of the outer sheath 106. The size and configuration of the lumen 132 are designed to fit and accommodate the inner blade 108.

[0028] As Figure 2As shown, the inner blade 108 includes a proximal cutting end 134 and a distal connection end 136 (also referred to as “hub” 164). In the depicted embodiment, the inner blade 108 is elongated and tapered, narrowing towards the proximal cutting end 134. The proximal cutting end 134 of the inner blade 108 includes a head 138 having a plurality of cutting teeth 140. In Figure 2 the depicted embodiment, the head 138 of the proximal cutting end 134 is trapezoidal, with its width increasing in the proximal direction. The distal connection end 136 includes a disk 142 having a plurality of slots 144 and an opening 146 extending therethrough. The size and configuration of the disk 142 are designed to fit within a hole 124 in the distal end 122 of the bottom portion 112. Additionally, the opening 146 in the disk 142 is positioned such that it aligns with a clearance 128 in the distal end 122 of the bottom portion 112. The purpose of the distal connection end 136 of the inner blade 108 and the distal end 122 of the bottom portion 112 is to facilitate connection of the sheathed blade assembly 100 to the saw head 160 ( Figure 7 ).

[0029] Also as Figure 2 shown, the sheathed blade assembly 100 further includes one or more ball bearings 148 between the top portion 110 of the outer sheath 106 and the inner blade 108 and between the bottom portion 112 of the outer sheath 106 and the inner blade 108. The ball bearings 148 are disposed or positioned on both sides of the inner blade 108 and roll relative to the inner blade 108 and the top portion 110 and bottom portion 112 of the outer sheath 106. Thus, the ball bearings 148 allow the inner blade 108 to move and minimize contact between the inner blade 108 and the outer sheath 106. The ball bearings 148 may be embedded in blind holes or slots (not shown) in the top portion 110 and bottom portion 112 of the inner blade 108 or the outer sheath 106. The ball bearings 148 project beyond the surface of the inner blade 108 or the outer sheath 106 to maintain a gap between the inner blade 108 and the outer sheath 106.

[0030] Now referring to Figure 3 and Figure 4 , a distal schematic view and a side schematic view of the sheathed blade assembly 100 according to one embodiment are shown. Figure 3 The proximal end 102 of the sheathed blade assembly 100 is shown. In the depicted embodiment, the inner blade 108 is shown positioned within the lumen 132 of the outer sheath 106 (between the top portion 110 and the bottom portion 112). Also as Figure 3 shown, the ball bearings 148 are positioned within pits 150 in the top surface 152 of the inner blade 108.

[0031] Figure 4 A side view of the sheathed blade assembly 100 is shown. In the depicted embodiment, the inner blade 108 is positioned within the lumen 132 of the outer sheath 106. Figure 4 The inner blade 108 shown has two pits 150A, 150B, one pit 150A in the top surface 152 of the inner blade 108 and one pit 150B in the bottom surface 154 of the inner blade 108, wherein the ball bearings 148 are positioned within the pits 150A, 150B. In the depicted embodiment, the two pits 150A, 150B are staggered such that one pit 150A is distal to the other pit 150B relative to the proximal cutting end 134 of the inner blade 108. Although the size and configuration of the ball bearings 148 can be designed to fit within the pits 150A, 150B, the sheathed blade assembly 100 does not require the pits 150A, 150B. The ball bearings 148 can be limited by the size of the outer sheath 106 and the width of the inner blade 108 within the outer sheath 106. The staggered configuration of the ball bearings 148 provides a clearance between the inner blade 108 and the outer sheath 106, greatly reducing friction within the assembly, thereby reducing heat, wear, and the generation of metal particles. This clearance also allows for fluid lubrication of the moving parts of the sheathed blade assembly 100.

[0032] Now turning to Figure 5 and Figure 6 , a top perspective schematic view and an exploded perspective schematic view of the sheathed blade assembly 100 according to an alternative embodiment are shown. In Figure 5 and Figure 6 the alternative embodiment of the sheathed blade assembly 100 shown, the outer sheath 106 includes a plurality of incisions 146 (i.e., holes or openings). As Figure 5 shown, the top portion 110 of the outer sheath 106 includes three trapezoidal or triangular incisions 156A extending therethrough. However, any number of incisions 156A of any shape or configuration can be used.

[0033] In Figure 6In [the figure], the bottom portion 112 of the outer sheath 106 further includes a plurality of incisions 156B (i.e., holes or openings) extending therethrough. The bottom portion 112 of the outer sheath 106 further includes three trapezoidal or triangular incisions 156B extending therethrough (however, any number of incisions 156B of any shape or configuration may be used). In the depicted embodiment, the incisions 156B in the bottom portion 112 of the outer sheath 106 are aligned with the incisions 156A in the top portion 110 of the outer sheath 106. The incisions 156A, 156B reduce the contact surface area between the inner blade 108 and the outer sheath 106 and allow fluid from the surgical site to lubricate the moving parts. Accordingly, the incisions 156A, 156B reduce friction and wear within the sheathed blade assembly 100, thereby reducing the generation of heat and metallic particles in the sheathed blade assembly 100. To further reduce friction, wear, and heat, any surface of the inner blade 108 and the outer sheath 106 may further include a coating 158, such as a physical vapor deposition (PVD) coating, a diamond-like carbon coating, and / or a dry lubricant coating, such as tungsten disulfide.

[0034] Now referring to Figure 7 , a side perspective schematic view of a universal saw head 160 according to one embodiment is shown. In the depicted embodiment, the saw head 160 includes a chuck 162 (with an opening 170) for accommodating both the sheathed blade assembly 100 ( Figure 1 ) and the unsheathed (standard) blade 200. When using the sheathed blade 100, as Figures 1 to 2 shown, the chuck 162 secures the outer sheath 106 to hold it stationary while engaging and driving the inner blade 108 using the hub 164 of the inner blade 108. When using the unsheathed blade 200, the saw head 160 uses the hub (not shown) of the unsheathed blade 200 to engage and drive the unsheathed blade 200 because it has the same structure as the hub 164 of the sheathed blade assembly 100 ( Figure 2 ), while the chuck 162 provides sufficient clearance such that the standard blade 200 will not contact any mechanism associated with securing the outer sheath 106. Since the saw head 160 can accommodate the sheathed blade assembly 100 ( Figure 1 ) and the unsheathed (standard) blade 200, two different types of saw heads are not required, thereby reducing procurement costs and inventory. It can also improve the logistics in hospitals and surgical centers. As Figure 7 shown, a single universal saw head 160 also provides greater flexibility for the user (e.g., a surgeon) in selecting the blade type for various surgical resections during orthopedic surgery.

[0035] Briefly turning to Figure 8 and Figure 9, a side perspective schematic view of a sheathed blade assembly 100 and an unsheathed blade 200 connected to a general saw head 160 is respectively shown. As Figure 8 and Figure 9 shown by both, Figure 7 the general saw head 160 of

[0036] In Figure 8 , in an embodiment using the sheathed blade assembly 100, the chuck 162 grasps the arm 126 at the distal end 122 ( Figure 2 ) of the bottom portion 112 of the outer sheath 106. In particular, as Figure 10 shown, one or more raised areas 172 on the chuck 162 grip (or otherwise hold) the outer sheath 106 of the sheathed blade assembly 100 to keep it stationary, while the inner blade 108 floats substantially within the outer sheath 106. Thus, the chuck 162 is connected to the fixed outer sheath 106 without contacting the movable inner blade 108, as Figure 10 shown.

[0037] When using an unsheathed (standard) blade 200, as Figure 9 shown, the chuck 162 is connected to the hub of the unsheathed blade 200 (similar to the hub 164 of the sheathed blade assembly 100 ( Figure 2 )), but a clearance amount 168 is left between the blade 200 and the chuck 162 to prevent contact, overheating, and damage. Figure 9 The clearance amount 168 in Figure 10 can be created by a groove 174 in the chuck 162, such as Figure 9 shown. The groove 174 provides the clearance amount 168 (

[0038] Figure 10 between the chuck 162 and the unsheathed blade 200. Figure 10 Also shown are various other components of the chuck 162 and the saw head 160. In the depicted embodiment, the sheathed blade assembly 100 is attached to the chuck 162 (and the saw head 160) via a cover 176 and a conventional connector 178. In the depicted embodiment, the connector 178 is attached to the cover 176 and extends through the hub 164 of the sheathed blade assembly 100 and the chuck 162. Also as

[0039] All definitions defined and used herein shall be understood to prevail over dictionary definitions, definitions in documents incorporated by reference, and / or ordinary meanings of the terms defined.

[0040] Although various embodiments have been described and illustrated herein, those of ordinary skill in the art will readily envision various other devices and / or structures for performing the functions and / or obtaining the results and / or one or more of the advantages described herein, and each of such variations and / or modifications is considered to be within the scope of the embodiments described herein. More generally, those skilled in the art will readily understand that all parameters, dimensions, materials, and configurations described herein are exemplary, and the actual parameters, dimensions, materials, and / or configurations will depend on the one or more particular applications for which the teachings of the present invention are used. Using only routine experimentation, those skilled in the art will recognize or be able to ascertain many equivalent forms of the specific embodiments described herein. Accordingly, it should be understood that the foregoing embodiments are presented by way of example only, and that the embodiments may be practiced otherwise than as specifically described and claimed within the scope of the appended claims and their equivalents. Embodiments of the present disclosure relate to each and every individual feature, system, article, material, kit, and / or method described herein. Additionally, any combination of two or more such features, systems, articles, materials, kits, and / or methods is also included within the scope of the present disclosure if such features, systems, articles, materials, kits, and / or methods are not mutually inconsistent.

[0041] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, unless the context clearly dictates otherwise, the singular forms "a", "an" and "the" are also intended to include the plural forms. It should also be understood that the terms "comprise" (and any form of "comprise", such as "comprises" and "comprising"), "have" (and any form of "have", such as "has" and "having"), "include" (and any form of "include", such as "includes" and "including"), and "contain" (and any form of "contain", such as "contains" and "containing") are open-ended linking verbs. Thus, a method or apparatus that "comprises", "has", "includes" or "contains" one or more steps or elements. Similarly, a step of a method or an element of an apparatus that "comprises", "has", "includes" or "contains" one or more features has those one or more features, but is not limited to having only those one or more features. In addition, an apparatus or structure constructed in a certain way is at least constructed in that way, but may also be constructed in ways not listed.

[0042] All apparatus or steps in the appended claims, plus corresponding structures, materials, operations and equivalents of the functional elements, if any, are intended to include any structure, material or operation for performing the functions in combination with other claimed elements as specifically claimed. The description of the invention has been presented for purposes of illustration and description, but is not intended to be exhaustive or to limit the invention to the disclosed form. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the invention. The embodiments were chosen and described in order to best explain the principles and practical application of one or more aspects of the invention, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications suited to the particular use contemplated.

Claims

1. A surgical saw, comprising: A saw head, the saw head including a chuck having an opening configured to receive a movable blade; Wherein the blade is detachably connected within the chuck; A handpiece, the handpiece connected to the saw head, the handpiece having a drive mechanism; And Wherein the drive mechanism moves the blade.

2. The surgical saw according to claim 1, wherein, The movable blade includes a fixed outer sheath having a pair of arms.

3. The surgical saw according to claim 2, wherein the pair of arms connect the movable blade within the chuck.

4. The surgical saw according to claim 1, further comprising an amount of clearance between the blade and the chuck.

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