Novel femoral neck fracture fixing instrument

Abstract

A novel femoral neck fracture fixing instrument comprises a near-end sleeve, a far-end screw and an adjusting bolt. The adjusting bolt is arranged in the near-end sleeve, matched threaded sections are arranged in the adjusting bolt and the near-end sleeve, and the adjusting bolt is rotationally combined with the far-end bolt; matched meshing teeth are arranged on the far-end screw rod and the near-end sleeve; the adjusting bolt rotates to drive the near-end sleeve to move towards the first end of the far-end screw, and the adjusting bolt stops rotating after meshing teeth are meshed; the second end of the near-end sleeve is provided with two empennages, the intersection angle of the two empennages towards the upper part of the femur ranges from 90 degrees to 150 degrees, and the first ends of the empennages are close to one end of meshing teeth of the sleeve; the empennage first end is higher than the empennage second end, and the empennage side edge is an inclined straight edge which is gradually lowered from the empennage first end to the empennage second end. By means of the arrangement mode of the double empennages, damage to the lower portion of the thighbone can be effectively avoided, the difficulty of instrument implantation is reduced, the difficulty of nail retreating is increased, and the effective and reasonable nail retreating amplitude in the treatment process is guaranteed.

Description

Technical Field

[0001] The utility model belongs to the field of medical device technology, and particularly relates to the field of femoral fracture devices, specifically a new type of femoral neck fracture fixation device. Background Art

[0002] Femoral neck fractures are common in the middle-aged and elderly population, with common complications and high disability rates, which seriously affect the patient's prognosis. For non-displaced femoral neck fractures, internal fixation surgery is the first-line treatment option. Internal fixation treatment can achieve bone healing while preserving the femoral head, which is beneficial to the recovery of joint function and can even be better than the efficacy of joint replacement surgery. Traditional cannulated screw (CS) internal fixation technology has the disadvantage of a high failure rate and a high risk of nonunion or femoral head necrosis after surgery, resulting in poor prognosis for some patients.

[0003] Aiming at the characteristics of osteoporotic femoral neck fractures in the middle-aged and elderly, the existing technology 200710121931.7 anti-rotation self-locking fracture internal fixator still has the problems of large screw withdrawal range and poor fixation effect.

[0004] The utility model aims at solving the above technical problems and discloses a novel femoral neck fracture fixation device. Utility Model Content

[0005] For middle-aged and elderly patients with non-displaced femoral neck fractures, the prior art 200710121931.7 anti-rotation self-locking fracture internal fixator prevents excessive nail withdrawal by setting 1-3 tail wings on the proximal sleeve and 3-4 spiral blades on the distal screw. Generally, the more tail wings there are, the better the effect of preventing nail withdrawal. Therefore, the actual product solves the problem by rotating 3 tail wings. However, the setting of 3 uniform tail wings will cause a tail wing that contacts the lower area of ​​the femur. In this way, when the fixator is knocked into the corresponding femoral position, the lower tail wing will cause a large crack to the lower femoral body. In severe cases, the crack extension length will affect the bone healing after fixation. If the damage to the femoral body is avoided by reducing the lower tail wing, the amplitude of nail withdrawal during the recovery process will exceed the required amplitude after the entire fixator is placed, resulting in poor recovery of the fracture. The utility model provides a new femoral neck fracture fixation device in response to the above technical problems.

[0006] The specific technical solution is: a new type of femoral neck fracture fixation device, which includes

[0007] The proximal sleeve has a first end with a meshing tooth, a second end with a tail wing, and a hollow interior with a threaded section;

[0008] The distal end screw has a spiral blade disposed on the outer side of the first end and is sleeved and assembled with the sleeve at the second end; a meshing tooth 2 meshing with the meshing tooth 1 is disposed in the middle;

[0009] The first end is combined with the second end of the distal screw and can rotate after the combination but does not move relative to each other; the second end of the adjusting bolt is configured to fit the first threaded section; the adjusting bolt rotates to drive the proximal sleeve to move toward the first end of the distal screw, and the meshing tooth 1 meshes with the meshing tooth 2 and then stops rotating;

[0010] Two tail wings are arranged at the second end of the proximal sleeve, and the intersection angle range of the two tail wings toward the upper side of the femur is 90-150°, and the first end of the tail wing is close to one end of the meshing tooth, and the second end of the tail wing is far away from the meshing tooth end; the height of the first end of the tail wing is higher than the height of the second end of the tail wing, and the side edge of the tail wing is an inclined straight edge that gradually becomes lower from the first end of the tail wing to the second end of the tail wing.

[0011] The above-mentioned arrangement can effectively continue the existing technology of completing the action of the proximal sleeve approaching the distal screw by adjusting the bolt, and finally realizing the locking action, and because the double tail wings are arranged at an angle of 90-150° toward the top of the femur, it can ensure that the vibration degree to the top is small when the tail wing is knocked in, and the damage to the main body of the femur below is minimized; in addition, the height of the first end of the tail wing is higher than the height of the second end of the tail wing, and the side of the tail wing is an inclined straight edge that gradually becomes lower from the first end of the tail wing to the second end of the tail wing. The setting method can effectively reduce the difficulty of knocking in the tail wing, because when the first end and the second end are at the same height, when entering, the tail wing part that enters later has When the first end of the above-mentioned technical solution enters the femoral segment first, it is restricted by the greater friction force and will increase the difficulty of knocking in the entire sleeve. However, once the first end enters, the tail part that enters later is at a lower height and will follow the tail part that enters first, and will not be restricted by the femoral crack that enters first. Once the tail enters the appropriate position, the femoral crack will grow and heal. In this way, when the nail is withdrawn, because the second end of the tail is withdrawn first, and because the height of the first end of the tail is higher than that of the second end of the tail, it will greatly increase the difficulty of withdrawing the first end of the tail, and then increase the difficulty of withdrawing the entire fixator. Finally, even with the two tails, the effect of ensuring that the amplitude of the nail withdrawal is within a suitable range is achieved.

[0012] Furthermore, the central axes of the two tail wings are on the cross-section of the femur. This arrangement can ensure that the two tail wings are symmetrically arranged on both sides of the cross-section of the femur and face upward toward the femur, thereby ensuring that the two tail wings exert symmetrical force on the femur during the knock-in process and reducing the risk of femoral fracture caused by asymmetric force.

[0013] Furthermore, the first end portion and the second end portion of the tail wing are both provided with an inclined section that transitions obliquely to the outer side surface of the sleeve. The provision of the inclined section can effectively reduce the difficulty of initial entry and initial exit, thereby ensuring that the entire process proceeds smoothly.

[0014] Furthermore, the height difference between the first end of the tail wing and the second end of the tail wing is less than 1mm; preferably, it is set to 0.2-0.5mm; this height difference setting can effectively reduce the difficulty of knocking in the instrument, and can also effectively control the range of nail withdrawal within a reasonable range, avoiding failure to withdraw the nail and avoiding excessive nail withdrawal.

[0015] Furthermore, in order to avoid the tail of the proximal sleeve from not matching the bone surface after the proximal sleeve is inserted, causing damage to the soft tissue caused by the tail of the proximal sleeve exposed outside the bone surface, the tail of the proximal sleeve is configured as a matching curved surface that matches the shape of the bone surface at the implantation site.

[0016] Furthermore, the proximal sleeve including the matching curved surface is made by 3D printing. This arrangement can ensure effective matching with the patient's bone surface.

[0017] Furthermore, between the spiral blade of the screw and the second meshing tooth is a cylindrical rod portion, which is hollow and has a hollow cavity inside. A wall hole penetrating into the hollow cavity is arranged on the cylindrical rod portion, and a through channel penetrating into the hollow cavity is arranged in the adjusting bolt and the second end of the screw. This arrangement can effectively achieve the introduction of drugs that promote bone healing into the fracture area through the through channel, the hollow cavity and the wall hole.

[0018] Furthermore, liquid drugs such as PRP and blood products are available to promote bone healing.

[0019] Furthermore, the bottom surface of the tail wing is triangular, and the apex angle of the triangle is arc-shaped. This arrangement can effectively ensure the convenience of the tail wing in and out, and can also avoid excessive damage to the tissue due to the sharp apex angle.

[0020] Furthermore, the fixation device also includes a hollow screw arranged in parallel with the distal screw. When in use, the hollow screw is arranged in the direction of the distal screw away from the femoral neck. By using the hollow screw in conjunction with the distal screw, the fixation effect of the device on femoral neck fracture can be greatly improved.

[0021] Technical Effects

[0022] The double tails facing the upper part of the femur with an angle range of 90-150 degrees can effectively avoid damage to the lower part of the femur and reduce the risk of device implantation.

[0023] By setting the height of the first end of the tail wing higher than the height of the second end of the tail wing, and the side of the tail wing being an inclined straight edge that gradually becomes lower from the first end of the tail wing to the second end of the tail wing, the difficulty of implanting the instrument can be effectively reduced and the difficulty of removing the nail can be increased, ensuring that even with the setting of two tail wings, an effective and reasonable nail removal range can be guaranteed during the treatment process.

[0024] Through the effective coordination of the through-channel, the hollow cavity and the wall hole, the injection of drugs that promote bone healing can be ensured, thereby accelerating bone healing.

[0025] The use of a hollow screw in conjunction with a distal screw can greatly improve the fixation effect of the instrument on femoral neck fractures. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0027] Figure 2 This is a schematic diagram of the overall structure of the utility model from the rear side;

[0028] Figure 3 This is a schematic diagram of the structure of the utility model from the side;

[0029] Figure 4 It is a partial enlarged structural schematic diagram of the rear side view of the tail wing part of the utility model;

[0030] Figure 5 This is a partial enlarged structural diagram of the proximal sleeve portion of the utility model;

[0031] Figure 6 This is a schematic diagram of the structure of the distal screw portion of the utility model;

[0032] Figure 7 This is a schematic diagram of the structure of the adjusting bolt portion of the utility model;

[0033] Description of main reference numerals

[0034] 1. Proximal sleeve; 11. Engaging tooth 1; 13. Tail; 131. Tail first end; 132. Tail second end; 133. Inclined straight edge; 134. Inclined section; 14. Matching curved surface; 2. Distal screw; 21. Spiral blade; 22. Engaging tooth 2; 23. Annular cavity; 24. Cylindrical rod part; 25. Wall hole; 3. Adjusting bolt; 31. Threaded section 2; 32. Circular ring; 33. Through passage. DETAILED DESCRIPTION

[0035] Example 1

[0036] refer to Figure 1 , Figure 2 , Figure 4 A novel femoral neck fracture fixation device, comprising a proximal sleeve 1, a first end portion provided with a meshing tooth 11, a second end outer side provided with a tail 13, an inner hollow portion provided with a threaded section 1;

[0037] The distal end screw 2 has a spiral blade 21 disposed on the outer side of the first end and is sleeved and assembled with the sleeve at the second end; a meshing tooth 22 meshing with the meshing tooth 1 11 is disposed in the middle;

[0038] The first end of the adjusting bolt 3 is combined with the second end of the distal screw 2 and can rotate but does not move relative to each other after the combination; the second end of the adjusting bolt 3 is configured to be adapted to the threaded section 1; the adjusting bolt 3 rotates to drive the proximal sleeve 1 to move toward the first end of the distal screw 2, and the meshing tooth 11 meshes with the meshing tooth 22 and then stops rotating;

[0039] Two tail wings 13 are arranged at the second end of the proximal sleeve 1, and the intersection angle range of the two tail wings 13 toward the upper side of the femur is 90-150°, and the first end 131 of the tail wing is close to the end of the meshing tooth 11, and the second end 132 of the tail wing is far away from the end of the meshing tooth; the height of the first end 131 of the tail wing is higher than the height of the second end 132 of the tail wing, and the side of the tail wing 13 is an inclined straight edge 133 which gradually becomes lower from the first end 131 of the tail wing to the second end 132 of the tail wing.

[0040] Specifically: Reference Figure 6 and Figure 7 ; A threaded segment 2 31 is provided on the adjusting bolt 3, and the threaded segment 21 is adapted to the threaded segment 1. The first end of the adjusting bolt 3 is a circular ring 32, and an annular cavity 23 is provided at the second end of the distal screw rod 2, and the circular ring 32 extends into the annular cavity 23; the side wall of the annular cavity 23 confines the circular ring 32 in the annular cavity 23, ensuring that the circular ring 32 can rotate relative to the annular cavity 23, but cannot move in relative position.

[0041] The meshing teeth 11 are a circle of teeth arranged on the first end wall of the proximal sleeve 1; the meshing teeth 22 are another circle of teeth arranged in the middle of the distal screw 2 and adapted to the circle of teeth on the wall.

[0042] When in use, first drive the distal screw 2 with the adjusting bolt 3 into the femoral neck fracture position to realize the reduction of the femoral neck, then combine the distal screw 2 with the proximal sleeve 1, and then rotate the adjusting bolt 3. Because the threaded section one and the threaded section two 31 are adapted to each other, the proximal sleeve 1 can be driven to approach the distal screw. During the approaching process, the proximal sleeve 1 only moves along the longitudinal axis of the distal screw 2 and does not rotate. The rotational movement occurs in the annular cavity 23 of the circular ring 32 of the adjusting bolt 3 and the distal screw 2. Then the proximal sleeve 1 moves until the meshing teeth 11 on the proximal sleeve 1 mesh with the meshing teeth 22 on the distal screw 2 and stop moving. At the same time of meshing, the rotational movement of the sleeve is further locked, so that the instrument is effectively fixed in the set position, ensuring the fixation after the reduction of the femoral neck fracture.

[0043] In a more preferred embodiment, the central axes of the two tail wings 13 are on the cross-section of the femur. This arrangement can ensure that the two tail wings 13 are symmetrically arranged on both sides of the cross-section of the femur and face upward to the femur, thereby ensuring that the two tail wings 13 exert symmetrical force on the femur during the knock-in process and reducing the risk of femoral fracture caused by asymmetric force.

[0044] A more preferred embodiment is as follows Figure 3 The first end 131 and the second end of the tail wing are both provided with an inclined section 134 which is inclined to transition to the outer side of the sleeve. The setting of the inclined section 134 can effectively reduce the difficulty of initial entry and initial exit, ensuring that the whole process proceeds smoothly.

[0045] A more preferred embodiment is as follows Figure 4 ; The height difference between the first end 131 of the tail wing and the second end 132 of the tail wing is less than 1mm; preferably set to 0.2-0.5mm; this height difference setting can effectively reduce the difficulty of knocking in the instrument, and can also effectively control the range of nail withdrawal within a reasonable range, avoiding failure to withdraw the nail and avoiding excessive nail withdrawal.

[0046] A more preferred embodiment is as follows Figure 3 and Figure 5 In order to avoid the tail of the proximal sleeve 1 not matching the bone surface after the proximal sleeve 1 is inserted, causing damage to the soft tissue caused by the tail of the proximal sleeve 1 exposed outside the bone surface, the tail of the proximal sleeve 1 is set as a matching curved surface 14 that matches the shape of the bone surface at the implantation site.

[0047] In a more preferred embodiment, the proximal sleeve 1 including the matching curved surface 14 is a structure made by 3D printing. This arrangement can ensure effective matching with the patient's bone surface, and most importantly, can achieve personalized preparation for the patient, and personalized use can be completed by only preparing the proximal sleeve 1. The matching curved surface 14 can be obtained based on the patient's CT image and fitted to the tail of the proximal sleeve 1 image data.

[0048] A more preferred embodiment is as follows Figure 6 Between the spiral blade 21 of the screw and the meshing teeth 22 is a cylindrical rod portion 24, which is hollow and has a hollow cavity inside. A wall hole 25 penetrating into the hollow cavity is arranged on the cylindrical rod portion 24, and a through channel 33 penetrating into the hollow cavity is arranged in the adjusting bolt 3 and the second end of the screw. This arrangement can effectively achieve the introduction of drugs that promote bone healing into the fracture area through the through channel 33, the hollow cavity and the wall hole 25.

[0049] In a more preferred embodiment, the drug that promotes bone healing is a liquid drug such as PRP or blood products.

[0050] In a more preferred embodiment, the bottom surface of the tail wing 13 is triangular, and the apex angle of the triangle is arc-shaped. This arrangement can effectively ensure the convenience of entering and exiting the tail wing 13, and can also avoid excessive damage to tissues due to the sharp apex angle.

[0051] A more preferred embodiment is that the fixation device includes the rotational self-locking device involved in the above embodiment, named fixation device 1, and a hollow screw; the hollow screw is arranged parallel to the distal screw 2 of the fixation device 1, and is arranged below the distal screw 2 when in use.

[0052] The method of using the fixation device 1 combined with the hollow screw is to first place a guide pin outside the body in front of the affected hip to locate the axis of the femoral neck, and then insert two guide pins percutaneously along the axis of the femoral neck from the distal end of the greater trochanter to the femoral head under the guidance of fluoroscopy. The distal guide pin is a hollow screw guide pin, which is placed close to the femoral cortex in the anteroposterior position, tilted about 15°, and the needle tip is 5mm below the articular surface cartilage. The proximal guide pin is the fixation device 1 guide pin, which is placed along the axis of the femoral neck and kept parallel to the first guide pin. In the lateral position, both guide pins are in the center of the femoral neck. After the fluoroscopic guide pin position is satisfactory, an incision is made between the two guide pins to the bone surface. First, measure the depth along the distal guide pin, drill a hole, and screw in a hollow screw. Use the PFNA depth gauge to measure the depth along the distal guide pin, use its depth-limiting drill bit to drill a hole in the outer cortex, and gently tap the fixation device 1 to 7-10mm below the articular surface. Use fluoroscopy again to confirm that the fracture reduction is satisfactory and the position and length of the two internal fixators are good. After satisfactory reduction, the wound is rinsed and sutured layer by layer, and then bandaged with sterile dressings.

[0053] The above is a clear and complete description of the technical solutions in the embodiments of the utility model through specific specific embodiments. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Those skilled in the art can easily understand other advantages and functions of the utility model from the contents disclosed in this specification. The utility model can also be implemented or applied through other different specific implementation methods. In the absence of conflict, the above embodiments and features in the embodiments can be combined with each other. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

Claims

1. A novel femoral neck fracture fixation device, comprising: The proximal sleeve has a first end with a meshing tooth, a second end with a tail wing, and a hollow interior with a threaded section; The distal end screw has a spiral blade disposed on the outer side of the first end and is sleeved and assembled with the sleeve at the second end; a meshing tooth 2 meshing with the meshing tooth 1 is disposed in the middle; The first end of the adjusting bolt is combined with the second end of the distal screw rod and can rotate but does not move relative to each other after the combination; the second end of the adjusting bolt is configured to fit with the first threaded section; the rotation of the adjusting bolt drives the proximal sleeve to move toward the first end of the distal screw rod, and the meshing tooth 1 meshes with the meshing tooth 2 before the rotation stops; it is characterized in that: Two tail wings are arranged at the second end of the proximal sleeve, and the intersection angle range of the two tail wings toward the upper side of the femur is 90-150°, and the first end of the tail wing is close to one end of the meshing tooth, and the second end of the tail wing is far away from the meshing tooth end; the height of the first end of the tail wing is higher than the height of the second end of the tail wing, and the side edge of the tail wing is an inclined straight edge that gradually becomes lower from the first end of the tail wing to the second end of the tail wing.

2. The fixing device according to claim 1, characterized in that: The mid-axis of the two tails is on the transverse plane of the femur.

3. The fixing device according to claim 1, characterized in that: The first end portion and the second end portion of the tail wing are both provided with an inclined section which is inclinedly transitioned to the outer side surface of the sleeve.

4. The fixing device according to claim 1, characterized in that: The height difference between the first end portion of the tail wing and the second end portion of the tail wing is less than 1 mm.

5. The fixing device according to claim 4, characterized in that: The height difference between the first end portion of the tail wing and the second end portion of the tail wing is 0.2-0.5 mm.

6. The fixing device according to claim 1, characterized in that: The tail of the proximal sleeve is arranged as a matching curved surface matching the shape of the bone surface at the implantation site.

7. The fixing device according to claim 6, characterized in that: The proximal sleeve including the anastomotic curved surface is a 3D printed structure.

8. The fixing device according to claim 1, characterized in that: The cylindrical rod part is between the spiral blade of the screw and the second meshing tooth. The cylindrical rod part is hollow and has a hollow cavity inside. A wall hole penetrating into the hollow cavity is arranged on the cylindrical rod part. A through channel penetrating into the hollow cavity is arranged in the adjusting bolt and the second end of the screw.

9. The fixing device according to claim 1, characterized in that: The bottom surface of the tail wing is triangular, and the top angle of the triangle is arc-shaped.

10. The fixing device according to claim 1, characterized in that: The fixing device also includes a hollow screw arranged parallel to the distal screw rod.

11. The fixing device according to claim 10, characterized in that: The hollow screw is arranged on the distal end of the screw rod in a direction away from the femoral neck.

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