Adjustable external fixation frame for metatarsal bone lengthening

Abstract

The utility model discloses an adjustable external fixing frame for metatarsal bone lengthening relates to metatarsal bone lengthening technical field. Including support frame, adjusting screw rod, fixed steel needle, auxiliary steel needle, adjusting block, fixed block, fixed bolt, adjusting screw rod rotation connection support frame, adjusting block cover set screw rod, fixed block is fixedly connected in the one end of support frame near metatarsal proximal end through bolt, and two fixed steel needles and an auxiliary steel needle are fixedly connected through fixed bolt on fixed block, and the fixed steel needle of fixed block inserts metatarsal proximal end, and the auxiliary steel needle inserts adjacent metatarsal, and two fixed steel needles are fixedly connected through fixed bolt of adjusting block, and the fixed steel needle of adjusting block inserts metatarsal distal end, and the screw rod is rotated, and adjusting block realizes metatarsal tension along the length direction of support frame and moves and realizes metatarsal tension. The utility model discloses simple structure, utilizes three point and determines one face principle, and sets up three steel needles in support frame both sides, and the support is more stable, and the steel needle is not easy to incline, and the effect of operation lengthening is good.

Description

Technical Field

[0001] This utility model relates to the field of metatarsal bone lengthening technology, specifically to an adjustable external fixator for metatarsal bone lengthening. Background Technology

[0002] Metatarsals are long bones, consisting of five bones, numbered 1-5 from medial to lateral. The proximal end of each metatarsal is the base, the middle part is the body, and the distal end is the head. Congenital metatarsal microsomia is a rare foot deformity, most commonly caused by premature closure of the metatarsal epiphyseal plates. It has a strong genetic predisposition, with an incidence of 2-5 per 10,000. It can also be secondary to trauma; it can affect any metatarsal bone, with the 4th metatarsal being the most common; it can occur unilaterally or bilaterally, with a bilateral incidence as high as 75%; the incidence is higher in women, with a male-to-female ratio of 1:25. The short, upturned toes of the affected foot hinder shoe wearing, and painful calluses on the plantar surface are usually the main reasons patients seek medical attention. Surgical aims to improve the appearance of the toes, relieve pain, and restore the parabolic shape of the metatarsal heads. Currently, the most commonly used surgical method in clinical practice is gradual metatarsal lengthening, also known as callus lengthening. Metatarsal gradual lengthening surgery typically uses an external fixator to lengthen the patient's metatarsals. The external fixator contains steel pins, and the short metatarsals are lengthened by gradually increasing the distance between the pins to achieve the therapeutic goal. In practice, due to the small diameter of the metatarsals, large-diameter pins cannot be used; generally, 2.0mm diameter pins are used for fixation. However, during the lengthening process, the traction of the skin, tendons, and muscles can cause stress on the pins, leading to bending or tilting, which can affect callus healing. Utility Model Content

[0003] The technical problem to be solved by this utility model is to provide an adjustable external fixator for metatarsal bone lengthening. It has a simple structure and uses the principle of three points fixing one surface. Three steel pins are set on both sides of the support frame, which makes the support more stable and the steel pins are not easy to tilt, resulting in a good surgical lengthening effect.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows: an adjustable external fixator for metatarsal bone lengthening, comprising a support frame, an adjusting screw, fixed steel pins, auxiliary steel pins, an adjusting block, a fixing block, and fixing bolts; the adjusting screw is rotatably connected to the support frame, and both ends of the adjusting screw are axially fixed to the support frame; the adjusting block is fitted with and screwed onto the adjusting screw; the fixing block is fixedly connected to the end of the support frame near the proximal end of the metatarsal bone by bolts; two fixed steel pins are fixedly connected to the fixing block by fixing bolts, and an auxiliary steel pin is also fixedly connected by bolts; the fixed steel pin and the auxiliary steel pin are located on opposite sides of the support frame; the fixed steel pin of the fixing block is inserted into the proximal end of the metatarsal bone, and the auxiliary steel pin is inserted into the adjacent metatarsal bone; two fixed steel pins are fixedly connected to the adjusting block by fixing bolts, and the two fixed steel pins of the adjusting block are inserted into the distal end of the metatarsal bone; rotating the adjusting screw causes the adjusting block to slide along the length direction of the support frame, ultimately achieving metatarsal lengthening.

[0005] Preferably, the support frame is an H-shaped structure with a closed top. The closed end of the H-structure has a first hole, and the cross brace of the H-structure has a second hole. Both ends of the adjusting screw have a section of optical shaft, which is rotatably connected to the first hole and the second hole, respectively. A shaft platform is provided at one end of the adjusting screw. The annular end face of the shaft platform is in contact with the cross brace, and one side of the fixing block is in contact with the circular end face of the shaft platform. The adjusting screw is axially fixed by the cross brace and the fixing block.

[0006] Preferably, the fixing block is a T-shaped structure, which consists of a horizontal part and a vertical part. The vertical part is provided with two ninth holes. The vertical part is embedded in the middle of the two vertical supports of the H-structure. Each vertical support is provided with two third holes. The fixing block is fixedly connected to the support frame by screwing the ninth holes and the third holes together.

[0007] Preferably, two eighth holes are provided through the horizontal part of the fixing block, and a seventh hole is provided perpendicular to the axis of the eighth holes. The fixing steel needle passes through the eighth hole, and the fixing bolt is screwed into the seventh hole. The fixing bolt fixes the fixing steel needle in the eighth hole. A tenth hole is provided in the vertical part of the fixing block. The auxiliary steel needle passes through the tenth hole and is fixed in the tenth hole by the bolt. The eighth hole and the tenth hole are located on both sides of the ninth hole, and the axes of the ninth hole, the tenth hole and the eighth hole are parallel.

[0008] Preferably, the adjusting block has a T-shaped structure, which includes a horizontal part and a vertical part. The horizontal part has two fifth holes and one fourth hole, with the axis of the fourth hole perpendicular to the axis of the fifth hole. The vertical part has a sixth hole, with the axis of the sixth hole perpendicular to the axes of the fifth and fourth holes. The adjusting screw is screwed into the sixth hole. The vertical part is embedded between the two vertical supports of the support frame and is slidably connected to the support frame. The fixing steel needle passes through the fifth hole, and the fixing bolt is screwed into the fourth hole to fix the fixing steel needle in the fifth hole.

[0009] Preferably, the external fixing frame also includes a gasket, which is a round gasket with a diameter that matches the diameter of the fourth hole. One end face of the round gasket is provided with two V-grooves that match the fixing steel pin.

[0010] The beneficial effects of adopting the above technical solution are as follows: An auxiliary steel pin is added to the fixing block of this utility model. The auxiliary steel pin is fixed on the metatarsal bone adjacent to the extended metatarsal bone. According to the principle of three points determining one plane, the auxiliary steel pin and the two fixing steel pins form a fixing plane, which solves the problem of insufficient stability of the single-sided external fixation bracket, increases the stability of the proximal metatarsal support frame and steel pin, and promotes callus healing.

[0011] This invention adds a gasket with a V-groove. The steel needle is inserted into the V-groove, increasing the contact area and firmly fixing the steel needle. This increases the stability of the steel needle, making it less prone to tilting, and reduces the possibility of the fixing bolt loosening due to the movement of the steel needle. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the main structure of this utility model; Figure 2 This is a top view of the structure of this utility model; Figure 3 This is a structural schematic diagram of the support frame; Figure 4 This is a schematic diagram of the adjusting block; Figure 5 This is a schematic diagram of the fixed block structure; Figure 6 This is a cross-sectional schematic diagram of the connection between the fixed steel pin and the washer; In the diagram: 1. Support frame; 11. First hole; 12. Second hole; 13. Third hole; 2. Adjusting screw; 3. Fixing steel pin; 4. Auxiliary steel pin; 5. Adjusting block; 51. Fourth hole; 52. Fifth hole; 53. Sixth hole; 6. Fixing block; 61. Seventh hole; 62. Eighth hole; 63. Ninth hole; 64. Tenth hole; 7. Fixing bolt; 8. Washer; 81. V-groove. Detailed Implementation

[0013] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0014] like Figure 1-2As shown, the adjustable external fixator includes a support frame 1, an adjusting screw 2, fixed steel pins 3, auxiliary steel pins 4, an adjusting block 5, a fixing block 6, and fixing bolts 7. The adjusting screw 2 is rotatably connected to the support frame 1, and both ends of the adjusting screw 2 are axially fixed to the support frame 1. The adjusting block 5 is fitted with and screwed onto the adjusting screw 2. The fixing block 6 is fixedly connected to the end of the support frame 1 near the proximal metatarsal bone by bolts. Two fixed steel pins 3 and one auxiliary steel pin 4 are fixedly connected to the fixing block 6 by fixing bolts 7. The fixed steel pins 3 and the auxiliary steel pin are located on opposite sides of the support frame 1. The fixed steel pins 3 of the fixing block 6 are inserted into the proximal metatarsal bone, and the auxiliary steel pin 4 is inserted into the adjacent metatarsal bone. Two fixed steel pins 3 are fixedly connected to the adjusting block 5 by fixing bolts 7. The two fixed steel pins 3 of the adjusting block 5 are inserted into the distal metatarsal bone. Rotating the adjusting screw 2 moves the adjusting block 5 along the length of the support frame 1, achieving metatarsal extension.

[0015] Specifically, such as Figure 3 As shown, the support frame 1 has an H-shaped structure. The top of the H-structure is closed, and the closed end of the H-structure has a first hole 11. The cross brace of the H-structure has a second hole 12. Both ends of the adjusting screw 2 have a section of optical shaft. The two sections of optical shaft are rotatably connected to the first hole 11 and the second hole 12, respectively. A shaft platform is provided at one end of the adjusting screw 2. The annular end face of the shaft platform is in contact with the cross brace. One side of the fixing block 6 is in contact with the circular end face of the shaft platform. The adjusting screw 2 is axially fixed by the cross brace and the fixing block 6.

[0016] like Figure 5 As shown, the fixing block 6 has a T-shaped structure, which consists of a horizontal part and a vertical part. The vertical part has two ninth holes 63. The vertical part is embedded in the middle of the two vertical supports of the H structure. Each vertical support has two third holes 13. The fixing block 6 is fixedly connected to the support frame 1 by bolts screwed into the ninth holes 63 and the third holes 13.

[0017] Two eighth holes 62 are provided through the horizontal part of the fixing block 6, and a seventh hole 61 is also provided. The axis of the eighth hole 62 is perpendicular to the seventh hole 61. The fixing steel needle 3 passes through the eighth hole 62. The fixing bolt 7 is screwed into the seventh hole 61. The fixing bolt 7 fixes the fixing steel needle 3 in the eighth hole 62. A tenth hole 64 is provided in the vertical part of the fixing block 6, and an auxiliary steel needle 4 passes through the tenth hole 64. Similarly, the auxiliary steel needle 4 is fixed in the tenth hole 64 by bolts. The eighth hole 62 and the tenth hole 64 are located on both sides of the ninth hole 63.

[0018] like Figure 4As shown, the adjusting block 5 has a T-shaped structure, which includes a horizontal part and a vertical part. The horizontal part has two fifth holes 52 and one fourth hole 51. The axis of the fourth hole 51 is perpendicular to the axis of the fifth hole 52. The vertical part has a sixth hole 53, the axis of which is perpendicular to the axes of the fifth hole 52 and the fourth hole 51. The sixth hole 53 is a threaded hole, and the adjusting screw 2 is screwed into it. The vertical part is fitted between the two vertical supports of the support frame 1 and is slidably connected to the support frame 1; the fixing steel needle 3 passes through the fifth hole 52, and the fixing bolt 7 is screwed into the fourth hole 51, fixing the fixing steel needle 3 within the fifth hole 52.

[0019] During installation, the horizontal part of the adjusting block 5 is first secured within the two vertical supports of the support frame 1. Then, the adjusting screw 2 is inserted through the open end of the support frame 1, passing through the sixth hole 53 of the adjusting block 5 until its top protrudes from the closed end of the support frame 1. Next, the horizontal part of the fixing block 6 is secured within the two vertical supports of the support frame 1, holding the adjusting screw 2 in place and axially limiting its movement. The ninth hole 63 is a threaded hole; a bolt passes through the vertical support of the support frame 1 and is screwed into the ninth hole 63, thus fixing the support frame 1 to the fixing block 6. After rotating the adjusting screw 2 and moving the adjusting block 5 to the appropriate position, the steel needle is secured with a bolt. Finally, the fixing steel needle 3 is inserted into the extended phalanx, and the auxiliary steel needle 4 is inserted into the adjacent phalanx. Simultaneously, after the adjusting block 5 is moved to the appropriate position, a set screw can be connected to its side and secured to the adjusting screw 2 to prevent displacement of the adjusting block 5 during use. This is a common technique; the set screw is not shown in the drawings.

[0020] When the position of the fixed steel pin 3 on the adjusting block 5 needs to be adjusted, simply use a tool to rotate the adjusting screw 2. The adjusting block 5 will slide along the vertical support of the support frame 1 until it reaches the appropriate position. Then, insert the fixed steel pin 3 into the extended metatarsal bone. When replacing the steel pin, simply loosen the fixing bolt 7 and pull out the steel pin for replacement. The auxiliary steel pin 4 is fixed and replaced using the same method.

[0021] To better secure the steel needle, shims 8 are placed inside the fourth hole 51 and the seventh hole 61. Figure 6 As shown, the gasket 8 is a round gasket, and the diameter of the round gasket matches the diameter of the fourth hole 51. One end face of the round gasket has two V-grooves 81, and the fixing steel pin 2 fits perfectly into the V-grooves 81. Tightening the fixing bolt 7 presses the gasket 8 firmly onto the fixing steel pin 3, making the fixing steel pin 3 more stable, less prone to tilting, and preventing the fixing bolt 7 from loosening.

[0022] The above are merely preferred embodiments of this utility model, but the scope of protection of this utility model is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in this utility model, based on the technical solution and inventive concept of this utility model, should be included within the scope of protection of this utility model.

Claims

1. An adjustable external fixator for metatarsal bone lengthening, characterized in that, The system includes a support frame (1), an adjusting screw (2), a fixing steel pin (3), an auxiliary steel pin (4), an adjusting block (5), a fixing block (6), and a fixing bolt (7). The adjusting screw (2) is rotatably connected to the support frame (1), and both ends of the adjusting screw (2) are axially fixed to the support frame (1). The adjusting block (5) is fitted with and screwed onto the adjusting screw (2). The fixing block (6) is fixedly connected to one end of the support frame (1) near the proximal metatarsal bone by bolts. The fixing block (6) is fixedly connected to two fixing steel pins (3) by fixing bolts (7). An auxiliary steel needle (4) is fixedly connected by bolts. The fixed steel needle (3) and the auxiliary steel needle are located on both sides of the support frame (1). The fixed steel needle (3) of the fixed block (6) is inserted into the proximal end of the metatarsal bone, and the auxiliary steel needle (4) is inserted into the adjacent metatarsal bone. The adjusting block (5) is fixedly connected to two fixed steel needles (3) by fixing bolts (7). The two fixed steel needles (3) of the adjusting block (5) are inserted into the distal end of the metatarsal bone. The adjusting screw (2) is rotated, and the adjusting screw (2) drives the adjusting block (5) to slide along the length direction of the support frame (1).

2. The adjustable external fixator for metatarsal bone lengthening according to claim 1, characterized in that, The support frame (1) is an H-shaped structure. The top of the H structure is closed. The closed end of the H structure is provided with a first hole (11). The cross brace of the H structure is provided with a second hole (12). Both ends of the adjusting screw (2) have a section of optical shaft. The two sections of optical shaft are respectively rotatably fitted in the first hole (11) and the second hole (12). A shaft platform is provided at one end of the adjusting screw (2). The annular end face of the shaft platform is in contact with the cross brace. One side of the fixing block (6) is in contact with the circular end face of the shaft platform. The adjusting screw (2) is axially fixed by the cross brace and the fixing block (6).

3. An adjustable external fixator for metatarsal bone lengthening according to claim 2, characterized in that, The fixing block (6) is a T-shaped structure, which consists of a horizontal part and a vertical part. The vertical part is embedded in the middle of the two vertical supports of the H structure. The vertical part is provided with two ninth holes (63), and each vertical support is provided with two third holes (13). The fixing block (6) is fixedly connected to the support frame (1) by screwing the ninth holes (63) and the third holes (13).

4. An adjustable external fixator for metatarsal bone lengthening according to claim 3, characterized in that, Two eighth holes (62) are provided through the horizontal part of the fixing block (6), and a seventh hole (61) is provided perpendicular to the axis of the eighth hole (62). The fixing steel needle (3) passes through the eighth hole (62), and the fixing bolt (7) is screwed into the seventh hole (61). The fixing bolt (7) fixes the fixing steel needle (3) in the eighth hole (62). A tenth hole (64) is provided in the vertical part of the fixing block (6). The auxiliary steel needle (4) passes through the tenth hole (64) and is fixed in the tenth hole (64) by bolts. The eighth hole (62) and the tenth hole (64) are located on both sides of the ninth hole (63). The axes of the ninth hole (63), the tenth hole (64) and the eighth hole (62) are parallel.

5. An adjustable external fixator for metatarsal bone lengthening according to claim 2, characterized in that, The adjusting block (5) has a T-shaped structure, which includes a horizontal part and a vertical part. The horizontal part has two fifth holes (52) and one fourth hole (51). The axis of the fourth hole (51) is perpendicular to the axis of the fifth hole (52). The vertical part has a sixth hole (53). The axis of the sixth hole (53) is perpendicular to the axes of the fifth hole (52) and the fourth hole (51). The adjusting screw (2) is screwed into the sixth hole (53). The vertical part is embedded between the two vertical supports of the support frame (1) and is slidably connected to the support frame (1). The fixing steel needle (3) passes through the fifth hole (52). The fixing bolt (7) is screwed into the fourth hole (51) and fixes the fixing steel needle (3) in the fifth hole (52).

6. An adjustable external fixator for metatarsal bone lengthening according to claim 5, characterized in that, The external fixing frame also includes a gasket (8), which is a round gasket with a diameter that matches the diameter of the fourth hole (51). One end face of the round gasket is provided with two V-grooves (81), which match the fixing steel pin (3).

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