BONE CUTTING TOOL ASSEMBLY FOR ARTIFICIAL JOINT SURGERY

Provided are a bone cutting tool assembly for artificial joint surgery. The assembly comprises a guide unit including a body having at least one guide slit and an anchor configured to extend from a side of the body, having a plurality of pin insertion holes; and a length measuring unit including a reference module having a slit insertion part inserted into the guide slit and a moving guide part extending in a direction perpendicular to a surface of the slit insertion part, and a position variable module slidingly coupled to the reference module through the moving guide part.

A. TECHNICAL FIELD

The present disclosure relates to cutting a bone during artificial joint surgery, and more specifically, to a bone cutting tool assembly for artificial joint surgery that guides a cutter of a bone cutting device in a direction perpendicular to a longitudinal direction of the bone so that a cutting section of the bone is perpendicular to the longitudinal direction of the bone.

B. DESCRIPTION OF THE RELATED ART

As human lifespan has greatly increased compared to the past, cartilage constituting each joint that plays an important role in human body movement is completely worn out before the end of human lifespan, and degenerative arthritis occurs frequently, and this causes a significant decrease in quality of life in the process of spending the rest of human life.

Recently, in order to medically solve these problems, artificial joint surgery that replaces the original joint with metal, plastic, or ceramic has been actively performed, and furthermore, research activities on surgical techniques for better surgical results.

In general, artificial joint surgery can be applied to all joints, but most of them are performed on the hip joint and knee joint. In this case, the surface of the bone forming the joint is finely trimmed, thin special metal is covered, and plastic (polyethylene insert) is placed between the femur and tibia. By allowing it to act as a cartilage, it allows the hip and knee joints to move flexibly and normally.

In order to do this, the end of the bone constituting the joint is cut by a predetermined length, and a process of inserting a replacement artificial joint having a shape corresponding to the cut portion is performed.

However, in the past, the process of cutting a bone by a predetermined length often relied on, the operator's eye measurement or his/her experience using surgical instruments, so a situation in which the replacement joint did not fit accurately often occurred, which causes a significant drop in the patient's satisfaction with surgery.

In order to solve this problem, a device for guiding a cutter that directly cuts bone in the process of cutting bone has been devised, but the conventionally developed guide devices mostly set an approximate cutting position through. an intramedullary femoral implant device. Because of this, there is a problem that some part of the error occurs. Therefore, a method for solving these problems is required.

SUMMARY OF THE DISCLOSURE

In one aspect of the present disclosure, a bone cutting tool assembly comprises a guide unit including a body having at least one guide slit and an anchor configured to extend from a side of the body, having a plurality of pin insertion holes; and a length measuring unit including a reference module having a slit insertion part inserted into the guide slit and a moving guide part extending in a direction perpendicular to a surface of the slit insertion part, and a position variable module slidingly coupled to the reference module through the moving guide part.

The length measuring unit may be formed in a pair.

The moving guide part may include an indicator for measuring a length on a surface of the moving guide part.

The position variable module may include a linear moving part formed to be movable along the moving guide part and a reference measuring part connected to the linear moving part in parallel to the slit insertion part.

The linear moving part may be coupled to a movement restraining unit to selectively stop a movement of the linear moving part.

The bone cutting tool assembly may further comprise a pair of protection units coupled to both side of the guide unit, respectively, each the protection unit may include an outer extension extending in a longitudinal direction of the guide unit, a bending part extending in a direction perpendicular to the longitudinal direction of the outer extension from a side of the outer extension and a mounting part inserted into a groove formed on a side of the body of the guide unit.

The bone cutting tool assembly may further comprise a positioning unit including a fixing piece inserted into the guide slit of the guide unit and a fixing bar formed in a parallel to the fixing piece and a reference setting unit having a mount hole into which the fixing bar is inserted.

The moving guide part may have a stopper protruding outward from a circumference of the moving guide part at a distal portion of the moving guide part.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

It shall also be noted that the terms “coupled,” “connected,” “linked,” or “communicatively coupled” shall be understood to include direct connections, indirect connections through one or more intermediary devices.

Furthermore, one skilled in the art shall recognize: (1) that certain steps may optionally be performed; (2) that steps may not be limited to the specific order set forth herein; and (3) that certain steps may be performed in different orders, including being done contemporaneously.

Reference in the specification to “one embodiment,” “preferred embodiment,” “an embodiment,” or “embodiments” means that a particular feature, structure, characteristic, or function described in connection with the embodiment is included in at least one embodiment of the disclosure and may be in more than one embodiment. The appearances of the phrases “in one embodiment,” “in an embodiment,” or “in embodiments” in various places in the specification are not necessarily all referring to the same embodiment or embodiments.

The terms “comprise/include” used throughout the description and the claims and modifications thereof are not intended to exclude other technical features, additions, components, or operations.

Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well. Also, when description related to a known configuration or function is deemed to render the present disclosure ambiguous, the corresponding description is omitted.

FIGS.1to8are a diagram illustrating a bone cutting guide tool assembly for artificial joint surgery according to embodiments of the present disclosure.

As depicted, the bone cutting tool assembly may include a guide rod10, a reference setting unit20, a positioning unit30, a guide unit100, a length measuring unit200, and a protection unit300. Hereinafter, throughFIGS.1to5, the each of the components of the bone cutting tool assembly will be described according to the order used in the artificial joint surgery.

FIG.1is a view of an assembly in which a guide rod, the reference setting unit, and the positioning unit that are coupled together in a bone cutting tool assembly for artificial joint surgery according to an embodiment of the present disclosure,FIG.2is a view illustrating a guide rod in a bone cutting tool assembly for artificial joint surgery according to an embodiment of the present disclosure, andFIG.3is a view of an assembly in which the reference setting unit20and the positioning unit30are engaged with each other in a bone cutting tool assembly for artificial joint surgery according to an embodiment of the present disclosure.

Each of the components shown inFIGS.1to3is components that are previously used before using the guide unit100, the length measuring unit200and the protection unit200during artificial joint surgery.

In the following description, terms indicating directions are based on the directions indicated in the drawings. However, the term is only set for convenience of explanation and is not intended to limit the rights of the present invention.

As depicted inFIG.2, the guide rod10may be formed by T-shaped structure and be provided to be inserted into a bone through a hole drilled at the end of the bone to be operated. In embodiments, the guide rod10may include a rod part11which is formed long in the longitudinal direction and a grip part12which is provided at the end of the rod part so that the operator can grip the grip part12. In embodiments, a distal part of the rod part11may be introduced into a drilling hole formed in the bone, and the distal part of the rod part11may be formed in a shape in which the cross-sectional area is gradually reduced to facilitate insertion into the hole of the bone. In embodiments, the grip part12may be provided at a proximal part of the rod part11and may be vertically connected to the rod part so that the operator can easily grip it.

As depicted inFIG.3, the reference setting unit20may have a through hole23which the rod part11of the guide rod10passes through, and a reference plane21forming an angle perpendicular to the rod part11in a state in which the reference plane21is partially in contact with the maximum protrusion of the end of the bone. In addition, the reference setting unit20may further have a pair of mount holes22that are driven therein in a direction perpendicular to the through hole23and the pair of mount holes22may be spaced apart from each other. The positioning unit30may include a base31, a fixing piece33extending from one end of the base31in a direction perpendicular to a surface of the base31, and a pair of fixing bars32extending from the other end of the base31in a direction perpendicular to the surface of the base31. In embodiments, the pair of fixing bars32may insert into the pair of mount holes22so that the positioning unit30is tightly engaged with the reference setting unit20. In embodiments, the fixing piece may be inserted into a guide slit111described later in conjunction withFIG.6. Such the positioning unit30may support the guide unit100, which will be described later, to be seated at a predetermined position on the bone in a state in which the positioning unit30is fixed to the reference setting unit20.

FIG.4is a perspective view of an assembly in which a guide unit, a length measuring unit and a protection unit are coupled together in a bone cutting guide tool assembly for artificial joint surgery according to an embodiment of the present disclosure,FIG.5is an exploded perspective view of the assembly of theFIG.4,FIG.6is a view illustrating a guide unit of a bone cutting guide tool assembly for artificial joint surgery according to an embodiment of the present disclosure,FIG.7is a view illustrating a length measuring unit of a bone cutting guide tool assembly for artificial joint surgery according to an embodiment of the present disclosure,FIG.8is a view illustrating a protection unit of a bone cutting guide tool assembly for artificial joint surgery according to an embodiment of the present disclosure.

Each of the components shown inFIGS.4to8are components that are used after performing a function of the guide rod10, the reference setting unit20and the positioning unit30during artificial joint surgery.

As depicted inFIG.6, the guide unit100may include a body110and an anchor120extending from a side of the body110. In embodiments, the body110may have a guide slit111that is formed in a longitudinal direction of the body110. The body110may have a plurality of guide slits. In this case, the plurality of the guide slits111may be disposed on the body110parallel to each other. Such the guide slit111is enabled to guide the movement of a cutter which the cutter cuts the end of the bone. In embodiments, the anchor120may have a plurality of pin insertion holes121therein so that the anchor120is fixed to a pin put into a bone. In embodiments, each of the plurality of pin insertion holes121may be disposed at a different position of the anchor120. Such the guide unit100may be mechanically coupled with the above-described the guide rod10, the reference setting unit20and the positioning unit30so that the guide unit100is seated at the end of the bone and fixed in an accurate position of the bone.

As depicted inFIG.7, the length measuring unit200may include a reference module210and a position variable module250, and such two components are mechanically coupled to each other. In embodiments, the length measuring unit200may be formed as a pair as shown inFIGS.4and5.

The reference module210may include a slit insertion part220formed to be inserted into the guide slit111of the guide unit100and a moving guide part230extending in a direction perpendicular to the surface of the slit insertion part220. In embodiments, the moving guide part230may have an indicator for measuring a length marked on an upper surface of the moving guide part230.

The position variable module250may include a linear moving part270inserted into the moving guide part230of the reference module210and formed to be movable along the moving guide part230, a reference measuring part260connected to the linear moving part270with a predetermined area to contact the end of the bone, and a movement restraining unit280coupled to the linear moving part270to selectively stop the movement of the linear moving part270. In embodiments, the slit insertion part220and the reference measuring part260may be disposed to have an angle perpendicular to the longitudinal direction of the bone. As the reference measuring part260of the position variable module250is contact the end of the bone, the operator can measure the length form the guide slit111of the guide unit100to the end of the bone.

As depicted inFIG.8, the protection unit300may include an outer extension310extending in the longitudinal direction of the guide unit100, a bending part320extending in a direction perpendicular to the longitudinal direction of the outer extension310from one side of the outer extension310, and a mounting part330for fixing the outer extension310to the guide unit100. In embodiments, the bending part320may include an attachment part321with a preset curvature so that tissues such as nerves and muscles around the bone can be attached thereon. In embodiments, the mounting part330may be formed in a form of a protrusion protruding toward the guide unit100and be inserted into a groove112formed on the side of the body110of the guide unit100described in conjunction with theFIG.6and coupled thereto. The protection unit300may be formed in a pair and selectively mounted on both sides of the guide unit100, respectively.

Thus, the protection unit300mounted on both sides of the guide unit100can allow the operator to secure a margin of the surgical area by attaching the tissue around the bone to the protection unit300during artificial joint surgery.

Hereinafter, the process of performing artificial joint surgery through each component of the present embodiment will be described.

FIGS.9to20are diagrams sequentially illustrating artificial joint surgery procedures using the bone cutting guide tool assembly according to embodiments of the present disclosure.

As depicted inFIG.9, the guide rod10, the reference setting unit20and the positioning unit30are prepared. Among this things, the reference setting unit20and the positioning unit30are previously coupled to each other, and then the guide rod10is structurally combined to the reference setting unit20by allowing the rod part11of the guide rod10inserted into the through hole23formed in the reference setting unit20.

FIG.10illustrates a state in which the guide rod, the reference setting unit20and the positioning unit30are combined to each other. In general, since the end of the bone1is formed to be curved, the maximum protruding part may be different depending on patients. The end of the bone1of the femoral region shown in the present embodiment forms a curve in which both side parts (1a,1b) protrude from the center, and among them, the first end1awas set as having a more protruding state compared to the other second end1b.

As depicted inFIG.10, after forming a drilling hole through a tool such as a drill at the end of the bone to be operated on, the rod part11of the guide rod10into the drilling hole to the bone is inserted and is drawn into the inside of the bone1. At this time, the rod part11may be inserted into the bone1by an operator so that a reference plane21of the reference setting unit20reaches to a protruding part formed at the end of the bone1.

In this state, as depicted inFIG.11, the operator may pull up the fixing bar32of the positioning unit30from the reference setting unit20so that the reference setting unit20and the positioning unit are separated from each other. Thereafter, the guide unit100may be positioned on the top of the bone1, and the fixing piece33of the positioning unit30may be inserted into the guide slit111of the guide unit100. Since a distance from the reference plane21of the reference setting unit20to the fixing piece33of the positioning unit30is constant, the position of the guide unit100can be set with respect to the fixing piece33of the positioning unit30through this process.

After setting the positions of each the positioning unit30, as depicted inFIG.12, a process of inserting a reference pin40into an arbitrary pin installation hole among a plurality of pin installation holes121formed in the anchor120of the guide unit100is performed thereby the reference pin40is driven into the bone1. Accordingly, the guide unit100can be fixed on the bone1. In this case, a fixing position of the reference pin40may be appropriately selected according to a surgical plan or a shape of the bone1.

In a state where the guide unit100is fixed to the upper part of the bone1, as depicted inFIG.13, the guide rod10, the reference setting unit20and the positioning unit30are removed, only the guide unit100remains on the bone1.

After that, as depicted inFIG.14, the pair of length measuring units200may be prepared, and the slit insertion part220provided in the reference module210of the length measuring unit200may be inserted into any guide slit111of the guide unit100.

In addition, as depicted inFIG.15, the pair of protection units300may be coupled to the side of the guide unit100. In embodiments, each of the protection units300may have at least mounting part330and the guide unit100may have the groove112corresponding to the mounting part330. Since the mounting part330of the protection unit300is formed in a protruding shape, the mounting part330can be coupled to the guide unit100by fitting into the groove of the body110of the guide unit100.

Next, as depicted inFIG.16, the position variable module250of the length measuring unit200can be linearly moved along the moving guide part230in the longitudinal direction of the moving guide part230so that the reference measuring part260comes into contact with the end of the bone1. For patients who need artificial joint surgery, the end of the bone1generally has a curve shape in which both sides1a,1bof the bone has a form protruding from the center of the end of the bone1and any one of the first end1aand the second end1bof the bone1has a more protruding form that the other end. In embodiments, in a state which one of the pair of the length measuring units200spaced apart from each other, one of the reference measuring parts260may be in contact with the first end1aof the bone1and another one of the reference measuring parts260may be in contact with the second end1bof the bone1.

FIG.17illustrates a view from the bottom of a bone in a state which a measuring parts is contact with an end of the bone.

As depicted inFIG.10, each of the reference measuring parts260is contact with the first end1aand second end1bof the bone1, respectively. At this time, the operator may measure a distance d1between the first reference measuring part260of the length measuring unit200and the guide slit111of the guide unit100, and a distance d2between the second reference measuring part260of the length measuring unit200and the guide slit111of the guide unit100through a scale marked on the moving guide part230, thereby determining whether the measured distance is appropriate for the surgical design.

Next, if the measured distance is appropriate the length measuring unit200may be removed from the guide unit100as depicted inFIG.18.

And then, as depicted inFIGS.19and20, a bone cutting device50including a cutter is prepared, the cutter of the bone cutting device40is inserted into the guide slit111of the guide unit100, and then the bone1is cut along the guide slit111by the cutter. Accordingly, the piece of cut bone is removed from the bone1, and then a process of mounting an alternative joint mechanism for an artificial joint to the cutting position of the bone1body may be performed.

FIG.21is an explored view illustrating another length measuring unit in a bone cutting tool assembly for artificial joint surgery according to an embodiment of the present disclosure andFIG.22is a view illustrating an operation of another length measuring unit in a bone cutting tool assembly for artificial joint surgery according to an embodiment of the present disclosure,

As depicted inFIGS.21and22, each component of the length measuring unit400may be similar to counterparts of the length measuring unit200inFIG.7. In embodiments, the moving guide part430may include a stopper432protruding outward from a circumference of the moving guide part430at a distal portion of the moving guide part430. In embodiments, the position variable module450may include an insertion hole471in which the moving guide part430pass through the linear moving part470and the reference measuring part460and a channel472may be formed on a part of an inner circumference of the insertion hole471corresponding to the stopper432. Regarding the combination of the reference module410and the position variable module450, firstly, as shown inFIG.21, the moving guide part430of the position variable module450may be inserted into the insertion hole471in a state where the position variable module450is rotated at a predetermined angle to match the position of the stopper432and the channel472. Secondly, as shown inFIG.22, after the stopper432of the moving guide part430is slid into the channel472, the reference module410and the position variable module450may be tightly coupled to each other by rotating the moving guide part430. Accordingly, since the liner moving part470is caught by the stopper432, it is possible to prevent the position variable module450from being separated from the reference module410.

FIG.23is a view illustrating a coupling structure of another protection unit and a guide unit in a bone cutting tool assembly for artificial joint surgery according to an embodiment of the present disclosure.

As depicted inFIG.23, each component510,520,530of the protection unit500may be similar to counterparts310,320,330of the protection unit300inFIG.8.

In embodiments, the mounting part530may be formed in a form of a hook bent parallel to the bending part520at a predetermined point thereof. The protection unit500may be coupled to the guide unit100in such a way that the mounting part530is inserted into the outer side of the guide slit111formed in the guide unit100.

In the description, numerous details are set forth for purposes of explanation in order to provide a thorough understanding of the present invention. However, it will be apparent to one skilled in the art that not all of these specific details are required in order to practice the present invention.

Additionally, while specific embodiments have been illustrated and described in this specification, those of ordinary skill in the art appreciate that any arrangement that is calculated to achieve the same purpose may be substituted for the specific embodiments disclosed. This disclosure is intended to cover any and all adaptations or variations of the present invention, and it is to be understood that the terms used in the following claims should not be construed to limit the invention to the specific embodiments disclosed in the specification. Rather, the scope of the invention is to be determined entirely by the following claims, which are to be construed in accordance with the established doctrines of claim interpretation, along with the full range of equivalents to which such claims are entitled.