[0028] The first embodiment is a combination structure of a dynamic bone screw and a bone plate for reduction of femoral head fractures, which includes a bone plate body 1, a slotted bone nail 2, two resistance blades 3, and a fixing screw 4. ,
[0029] Such as figure 1 , 2, 5, 6, the bone plate body 1 has a joint 12, the inner side of which is a concave arc surface, so that when it is attached to the femur, the contact area between the two can be increased; four perforations 120 penetrate the joint The inner and outer sides of 12 are separated by an appropriate distance; the extension 14 is a tube of appropriate length, and the outer edge of the outer end is connected to the upper end of the joint 12, and the longitudinal direction of the two is sandwiched between 120° and 140° The included angle makes the bone plate body 1 bend; the inner diameter of the shaft hole 140 in the extension part 14 adjacent to the outer end of the joint 12 is larger than the inner end of the inner end, and the shoulder at the junction of the two A stopping portion 142 is formed at the position; the two first limiting portions 144 are respectively set on the plane of the inner wall of the shaft hole 140, and extend an appropriate length from the outer end of the shaft hole 140 inward, so that the shaft hole 140 and The cross section of the corresponding part is slightly elliptical; there are also two first long grooves 146 provided on the inner wall of the shaft hole 140, and extend an appropriate length from the outer end to the inner end. In this embodiment, the two first limiting portions 144 are set to be one hundred and eighty degrees apart, and the two first long grooves 146 are respectively recessed at the corresponding first limiting portions 144.
[0030] The slotted bone nail 2 has a hollow shape with an appropriate length, and its outer end has an appropriate length, and is inserted into the extension portion 140 in a manner that can reciprocate along its axial direction. There is a tapping screw 20, the inner wall of the outer end is provided with an inner screw 22, and the two second limiting parts 24 are respectively a plane provided on the outer edge of the slotted bone screw 2, and extend from the outer end toward the inside. Length; Two second long grooves 26 are recessed on its outer edge, and extend an appropriate length along its axial direction, and pass through the second limiting portion 24, and extend an appropriate length from its outer end inward; when the bone When the plate body 1 is sleeved outside the outer end of the slotted bone nail 2 with its extension portion 14, each of the first limiting portion 144 and the second limiting portion 24 will abut against each other, and each of the first long slots 146 The second long groove 26 communicates with each other.
[0031] Such as Picture 8 Said, the two resistance blades 3 are in the shape of long strips with appropriate thickness and width, and the cross section is rectangular, and can be embedded in each of the first long groove 146 and the second long groove 26 at the same time. , The inner end is provided with a lead angle to reduce resistance or deviate from the axis during the process of implanting the femur. If necessary, the front end can be formed into a blade-like shape; a perforation is provided at the outer end for Cooperate with other tools for taking out the second resistance blade 3 which has been set in the femur.
[0032] The inner end of the fixing screw 4 can be used for screwing with the inner thread 22 of the outer end of the slotted bone nail 2, and the outer end with a larger outer diameter is formed with a suitable shape that can be matched with a screwdriver or a hexagonal wrench. And since the outer diameter of the outer end is larger than the inner diameter of the inner end of the shaft hole 140, it will be stopped by the stopper 142, and will always be left on the outer side of the shaft hole 140 of the extension part 14 when it is rotated. End.
[0033] During operation, first lock the slotted bone nail 2 into the fractured femoral head, and then use the extension part 14 of the bone plate body 1 to sleeve the outer end of the slotted bone nail 2 and make each of the first limiting positions The portion 144 and the second limiting portion 24 correspond to each other to prevent the slotted bone nail 2 from rotating therein; the joint portion 12 of the bone plate body 1 can be fixed to the bone plate body 1 through each of the through holes 120 by four fixing nails. On the femur.
[0034] The two resistance blades 3 are inserted between the first long groove 146 and the second long groove 26 that are opposite to each other, when the length of each resistance blade 3 is not greater than the length of each of the long grooves 146, 26 , It should be completely submerged into each of the long grooves 146, 26 so that the outer end does not protrude beyond the outer end of the slotted bone nail 2, while the inner end has a considerable length extending to the inside of the femoral head , As shown in Figure 7, and each of the resistance blades 3 will contact the femoral head with its rectangular inner end, thereby increasing the contact area between the two. In addition, the height of each resistance blade 3 protruding from the outer edge of the slotted bone nail 2 from each of the second long grooves 26 can be set to be greater than or equal to the height of the tapping screw 20 to further increase the aforementioned contact area.
[0035] Finally, take the fixing screw 4 to penetrate through the outer end of the extension 14, and after it is screwed to the outer end of the slotted bone nail 2, rotate the fixing screw 4, and since the outer end of the fixing screw 4 receives the The extension stopper 142 is blocked, and each of the first limiting portions 144 is in contact with each of the second limiting portions 24. Therefore, when the operator rotates the fixing screw 4, the bone plate body 1 With slotted bone nail 2, to traction the two corresponding parts of the fracture to reduce.
[0036] Such as Picture 11 As shown, the two baffle blades 3 protruding from both sides of the slotted bone nail 4 in the shape of a wing can effectively increase the contact area between the dynamic bone screw and the bone plate structure and the femoral head, and not only can increase it The fixation effect can also achieve the effect of reducing the amount of subsidence.
[0037] Since the inner end of each resistance blade 3 protrudes from the extension part 14 to have a considerable length, in actual use, the operator can preliminarily place the femoral head immediately adjacent to the femoral head before inserting the bone plate body 1 Long holes are drilled outside the two second long grooves 26 of the slotted bone nail 2 to facilitate the inner end of the two resistance blades 3 to extend into the femoral head.
[0038] The number and position of the resistance blades 3 are the best implementation. In practical applications, not only the number can be adjusted, the corresponding long grooves 146, 26 can also be set on a non-planar surface. Each of the first limiting portion 144 or the second limiting portion 24 is other parts of the shape. Or, the resistance blade 3 can also be changed in various ways,
