Detailed Description
Hereinafter, a tool 1 for bone surgery according to an embodiment of the present invention will be described with reference to the drawings.
The bone surgery tool 1 is a drill guide used for a surgery for inserting an implant such as a screw or a pin into a bone a, and guiding a drill (rod-shaped member) for opening a lower hole for implantation in the bone a. As shown in fig. 1, the tool 1 for bone surgery includes a rod (main body) 2 for guiding a drill, a receiving portion 3 opposed to the tip of the rod 2 in the longitudinal direction of the rod 2 and receiving the tip of the drill, and a hook-shaped support 4 for connecting the rod 2 and the receiving portion 3.
The rod 2 and the receiving portion 3 are disposed on both sides of the bone a in the radial direction, and hold the bone a in the radial direction. Then, a lower hole is formed in the radial direction of the bone a by a drill inserted into the rod portion 2.
The rod 2 is a cylindrical shape extending linearly, and has a through hole 2a penetrating in the longitudinal direction of the rod 2 and into which a drill is inserted. The diameter of the through hole 2a is slightly larger than the outer diameter of the drill, and is, for example, 1.6mm to 7 mm. In the through hole 2a, the drill is guided in the longitudinal direction of the rod 2 along the central axis of the through hole 2 a. The drill may be a commercially available drill for perforating bone. Alternatively, the bone surgery tool 1 may include a special drill adapted to the rod portion 2 and the receiving portion 3.
The annular tip end surface of the rod portion 2 has recesses at a plurality of positions in the circumferential direction, and tips 2b protruding toward the receiving portion 3 are formed between the recesses. The bone a can be held more stably by the tip 2b, and the drill can be prevented from wobbling when making a lower hole by the drill. Instead of the tip 2b, a projection protruding toward the receiving portion 3 may be provided at the tip of the rod portion 2.
The receiving portion 3 is a plate-like member orthogonal to an extension line of the central axis of the through hole 2a, and is disposed at a position spaced from the tip of the rod portion 2 in the longitudinal direction of the rod portion 2. The surface of the receiving portion 3 on the rod portion 2 side is a receiving surface 3a facing the opening of the through hole 2a in the tip of the rod portion 2. The receiving portion 3 receives the tip of the drill, which penetrates the through hole 2a and protrudes from the tip of the rod portion 2, on the receiving surface 3 a. The receiving surface 3a may be a flat surface or a curved surface along the surface shape of the bone a. The receiving portion 3 has a circular, elliptical, or other arbitrary shape in a plan view viewed along the direction of the central axis of the through-hole 2 a.
The outer dimension of the receiving portion 3 in the radial direction perpendicular to the longitudinal direction of the rod 2 is preferably larger than the outer dimension of the drill in the radial direction. According to this configuration, the distal end of the drill can be reliably received by the receiving portion 3, and the distal end of the drill penetrating the bone a can be accurately prevented from being exposed to the tissue around the bone a. In this case, the drill bit may be provided as a component of the bone surgery tool 1.
The outer dimensions of the radial receiving portion 3 may be the same as the outer dimensions of the radial rod portion 2. According to this configuration, when the tool 1 for bone surgery is observed from the proximal end side of the rod 2, the installation position of the receiving portion 3 in the body can be confirmed by an X-ray observation device or the like.
The strut 4 is bent in a substantially U-shape or a substantially C-shape and is arranged radially outward of the bone a so as to surround substantially half of the circumference of the bone a. The rod 2 is supported at one end of the support column 4 so as to be movable in the longitudinal direction of the rod 2, and the receiving portion 3 is fixed to the other end of the support column 4. The distance D between the central axis of the through hole 2a in the radial direction and the support column 4 is preferably about 15mm to 70mm in consideration of the width of the skin incision for inserting the bone surgery tool 1 into the body.
A cylindrical support portion 4a that supports the rod portion 2 so as to be movable in the longitudinal direction of the rod portion 2 is provided at one end of the support column 4. The support portion 4a is a female screw having a thread groove formed on an inner peripheral surface thereof. A male screw 2c connected to the female screw is provided on the cylindrical outer peripheral surface of the rod 2. The rotation of the rod 2 around the longitudinal axis of the rod 2 moves the rod 2 in a direction approaching the receiving portion 3, and the reverse rotation of the rod 2 moves the rod 2 in a direction separating from the receiving portion 3. In a state where the rotation of the rod 2 is stopped, the rod 2 is positioned in the longitudinal direction with respect to the support 4, and the distance between the tip of the rod 2 and the receiving portion 3 is fixed. Therefore, the distance between the tip of the rod 2 and the receiving surface 3a is adjusted according to the thickness of the bone a, and the bone a having various thicknesses can be firmly held by the rod 2 and the receiving portion 3.
Fig. 2 shows another example of the tool 1 for bone surgery according to the present embodiment. In the example of fig. 2, the outer peripheral surface of the rod portion 2 and the inner peripheral surface of the support portion 4a are smooth, respectively, and the support portion 4a supports the rod portion 2 so as to be smoothly movable in the longitudinal direction. The stay 4 is provided with a stopper 4b for temporarily fixing the rod 2 to the support 4 a. The stopper 4b is a knob screw, for example, a thumb screw, which penetrates from the outside to the inside of the support portion 4a in the radial direction. The rod 2 is fixed to the support 4a by the rotation of the knob screw 4b, and the fixing of the rod 2 to the support 4a is released by the reverse rotation of the thumb screw 4 b.
Fig. 3 shows another example of the tool 1 for bone surgery according to the present embodiment. In the example of fig. 3, a latch mechanism that positions the rod portion 2 with respect to the support portion 4a in the longitudinal direction is provided. The latch mechanism includes a plurality of grooves 2d formed in the outer peripheral surface of the rod portion 2 and arranged in the longitudinal direction of the rod portion 2, a protrusion 4c provided at one end of the support 4, and an urging member 4 d. The projection 4c is urged toward the rod 2 by an urging member 4d such as a spring and fitted into the groove 2 d. In a state where the projection 4c is fitted into the groove 2d, the rod portion 2 is positioned in the longitudinal direction with respect to the support portion 4 a. When a force in the longitudinal direction of a predetermined magnitude or more is applied to the rod portion 2, the rod portion 2 pushes the projection 4c against the biasing force of the biasing member 4d and moves in the longitudinal direction.
The groove 2d may have a shape that restricts the movement of the bar portion 2 only in one direction. For example, the latch mechanism may allow the movement of the rod portion 2 only in a direction approaching the receiving portion 3 like a ratchet mechanism. In addition to the mortise lock mechanisms 2d, 4c, 4d, a pin or screw for mechanically fixing the rod part 2 with respect to the support part 4a may be provided.
As shown in fig. 4, a scale 4e may be provided on the outer peripheral surface of the rod portion 2. The scale lines of the scale 4e are arranged in the longitudinal direction of the rod portion 2. The doctor can measure the distance between the tip of the rod 2 and the receiving portion 3 based on the value of the scale 4e at the position of the support portion 4a, for example.
Next, the operation of the tool 1 for bone surgery will be described.
Fig. 5 shows DTO (digital-to-bone surgery) as an example of the tool 1 for bone surgery. DTO is a method of osteotomy at a position farther than the rough surface B in the High Tibial Osteotomy (HTO) in order to continue the rough surface B on the proximal bone fragment C of the tibia a.
The bone surgery tool 1 can also be used for making a lower hole in a bone other than a tibia.
As shown in fig. 5, the tibia a is sandwiched in the front-rear direction at the position of the rough surface portion B by the rod portion 2 and the receiving portion 3, and the rod portion 2 is moved in a direction approaching the receiving portion 3 until the tip of the rod portion 2 and the receiving surface 3a of the receiving portion 3 come into contact with the surface of the tibia a. Thereby, the tibia a is gripped in the radial direction by the rod portion 2 and the receiving portion 3. In this case, the rod 2 is disposed on the front side of the tibia a, and the receiving portion 3 is disposed on the rear side of the tibia a.
Next, the drill 10 is inserted into the through hole 2a of the rod portion 2, and a lower hole is formed in the tibia a by the rotating drill 10. In the production of the lower hole, since the drill is guided straight along the center axis of the through-hole 2a, the lower hole extending straight along the extension line of the center axis of the through-hole 2a can be produced. Next, the drill 10 is pulled out from the lower hole and the through hole 2a, and the depth of the lower hole is measured using a depth gauge (not shown), and it is confirmed that the depth of the lower hole is appropriate. Next, an implant is inserted into the inferior hole of the tibia a, and the broad face portion B is fixed to the distal bone fragment of the tibia a by the implant. The bone surgery tool 1 may be provided with a measurement function for measuring the thickness of the tibia a.
As described above, according to the present embodiment, the receiving portion 3 is disposed on the opposite side of the bone a from the rod portion 2, and the drill 10 guides the rod portion 2 straight in the bone a toward the receiving portion 3. When the drill 10 penetrates the bone a, the tip of the drill 10 abuts against the receiving surface 3a on the surface of the bone a and is received by the receiving portion 3. This prevents the tip of the drill 10 from being exposed to the tissue around the bone a, and the tissue around the bone a can be reliably protected from the tip of the drill 10. In the case of DTO, the tip of the drill 10 penetrating the tibia a from the anterior to the posterior can be reliably prevented from being exposed to nerves, blood vessels, and the like existing in the posterior of the tibia a.
In the above embodiment, as shown in fig. 6A, a slip prevention member 5 for preventing slipping of the receiving surface 3a with respect to the surface of the bone a may be provided on the receiving surface 3 a. The anti-slip member 5 is constituted by, for example, a plurality of grooves or a plurality of projections formed on the receiving surface 3 a. The receptacle 3 can be stably positioned on the surface of the bone a by the anti-slip 5.
In the above embodiment, as shown in fig. 6B, a convex portion (engaging portion) 3B protruding toward the rod portion 2 may be provided on the receiving surface 3 a. The convex portion 3b is provided at a position radially offset from the drill so as not to interfere with the movement of the drill in the longitudinal direction. For example, in the case of a hollow drill, the convex portion 3b may be provided at the center portion of the receiving surface 3 a. In a state where the tip end of the drill is disposed at the receiving surface 3a or near the receiving surface 3a, the tip end portion (engaging portion) of the drill is engaged with the convex portion 3b in the radial direction, and the drill is radially overlapped with the receiving portion 3. This can stabilize the position of the tip of the drill with respect to the receiving portion 3.
In the above embodiment, as shown in fig. 6C, a recess 3C recessed toward the opposite side of the rod 2 and capable of receiving the tip of the drill may be provided in the center of the receiving portion 3 a. According to this structure, the hole can be reliably opened up to the end of the cortical bone.
In the above embodiment, as shown in fig. 7A and 7B, the bone grasping portion 6 may be provided at the distal end of the rod portion 2. The bone gripping portion 6 has a bone gripping surface 6a on the receiving portion 3 side. The bone gripping surface 6a is recessed toward the side opposite to the receiving portion 3, and curves along the surface of the bone a sandwiched between the receiving portion 3 and the bone gripping surface 6 a. By providing the bone gripping surface 6a, the contact area with the bone a can be increased, and the bone a can be gripped more stably. Fig. 7A and 7B show, as an example, a bone gripping surface 6a curved in one direction. The shape of the bone gripping surface 6a may be appropriately changed as long as the bone gripping surface 6a is disposed along the surface of the bone a and can grip the bone a.
The rod 2 is supported by the support 4a so as to be rotatable about the longitudinal axis in order to match the direction of curvature of the bone-grasping surface 6a with the direction of curvature of the surface of the bone a. In the example of fig. 7A and 7B, the male thread 2c and the female thread connected to each other are provided on the outer peripheral surface of the rod portion 2 and the inner peripheral surface of the support portion 4 a. The rod 2 is supported by the support 4 so as to be swingable about an axis in a direction perpendicular to the longitudinal axis.
In the above embodiment, the receiving portion 3 may have a visual confirmation portion that can be observed through the biological tissue by the observation device.
The observation device is a device that allows a visual confirmation unit to see through biological tissues such as bones and peripheral tissues, and is, for example, an X-ray observation device. As shown in fig. 8, the visual confirmation unit 7 is a mark constituting a part of the receiving unit 3. For example, the marker 7 is formed of an X-ray opaque material or a material such as resin that is different from the other portions of the receiving portion 3. Alternatively, the visual confirmation unit may be a through hole or a thin portion formed in the center of the receiving unit 3. The through hole as the visual confirmation part has a diameter smaller than that of the drill, for example, 0.5mm to 3 mm. The thin portion is thinner than the other portions of the receiving portion 3, and has a thickness of, for example, 0.5mm to 1.0 mm.
In the case where the receiving portion 3 is placed on the opposite side of the bone a from the doctor during the operation and is blocked by the bone a, the doctor cannot visually recognize the receiving portion 3. By providing the visual confirmation unit 7 in a part of the receiving unit 3, the doctor can observe the receiving unit 3 using the observation device.
In the above embodiment, the support 4 movably supports the rod part 2 in the longitudinal direction, and instead, the rod part 2 may be fixed to one end of the support 4.
In this case, the distance between the tip of the rod 2 and the receiving surface 3a of the receiving portion 3 is designed according to the thickness of the bone a to which the bone surgery tool 1 is applied.
The tool 1 for bone surgery can also be used for other purposes than a drill guide. For example, as shown in fig. 9 to 11, the tool 1 for bone surgery can also function as an implantation guide, a guide for temporary fixation, or a compression tool.
Fig. 9A and 9B show a method of using the bone surgery tool 1 as an implantation guide. The bone surgery tool 1 is used with a drill sleeve 20 for preparing a lower hole. The inner diameter of the through hole 2a of the rod 2 is slightly larger than the outer diameter of the drill sleeve 20. The outer diameter of the drill sleeve 20 is equal to or slightly larger than the outer diameter of the implant. The diameter of the through-hole 2a of the rod 2 is preferably 3mm to 8 mm.
As shown in fig. 9A, the bone a is held in the radial direction by the rod 2 and the receiving portion 3, the drill sleeve 20 is inserted into the through hole 2a of the rod 2, the drill 10 is inserted into the bone a through the drill sleeve 20, and a lower hole is created by the drill 10. Next, as shown in fig. 9B, the drill sleeve 20 is pulled out from the rod 2, and the implant 30 such as a screw is inserted into the through hole 2a of the rod 2. Thereby, the implant 30 can be inserted coaxially with the lower hole in the lower hole. As shown in fig. 9A and 9B, a slit 2e for visualizing the implant 30 in the rod portion 2 may be provided in the rod portion 2. For example, the slit 2e extends from the recess between the tips 2b toward the base end side. Based on the position of the implant 30 in the rod portion 2 as viewed through the slit 2e, the amount of insertion of the implant 30 into the lower hole can be visually confirmed.
Fig. 10A to 10C show a method of using the bone surgery tool 1 as a guide for temporary fixation.
As shown in fig. 10A, a tubular sleeve 40 for guiding a wire for temporary fixation is inserted into the through hole 2a of the rod portion 2. The sleeve 40 has a through hole that penetrates in the longitudinal direction of the sleeve 40 and into which a wire is inserted. The diameter of the wire is preferably 1.2mm to 3 mm. The sleeve 40 that is appropriately fitted into the through hole 2a of the rod portion 2 may be provided as a component of the bone surgery tool 1. As shown in fig. 10B, the drill sleeve 20 may be inserted into the through hole 2a of the rod portion 2, and the sleeve 40 may be inserted into the drill sleeve 20.
Next, as shown in fig. 10C, the wire 50 is inserted into the bone a through the sleeve 40, and the bone a and the rod 2 are temporarily fixed by the wire 50. Next, the sleeve 40 is pulled out from the rod 2, and a hollow drill is inserted into the through hole 2a of the rod 2 along the wire 50, and a lower hole is made in the bone a by the drill.
Fig. 11 shows a method of using the tool 1 for bone surgery as a compression tool.
As shown in fig. 11, a pressing member 60 having a pin 60a at its tip is inserted into the through hole 2a of the rod portion 2. The pressing member 60 is a rod-shaped solid member. The pin 60a presses the bone a, such as the thick face portion B, against the receiving portion 3. This enables a pressing force to be reliably applied to the bone fragments of the rough surface portion B, as compared with the case of pressing with the tip end of the rod portion 2. In order to maintain the state of pressing the bone a, the pressing member 60 may be fixed to the rod 2 by a pin 70 penetrating the rod 2 and the pressing member 60 in the radial direction.
Description of the symbols
1-tool for bone surgery, 2-rod (body), 2 a-through hole, 3-receiving part, 3 a-receiving surface, 3 b-convex part (engaging part), 4-pillar, 5-anti-slip part, 6 a-bone holding surface, 7-visual confirmation part, 10-drill (rod), a-bone.