CN102784002A - Tibial intramedullary nail - Google Patents

Abstract

The present invention relates to a novel tibial intramedullary nail, comprising a proximal end L1 (1), a distal end L2 (2) suitable for being inserted into the medullary cavity, and a center line between the proximal end (1) and the longitudinal axis of the intramedullary nail. The angle a between them is 18°-22°. The intramedullary nail can use the inner edge of the patellar key and the upper edge of the tibial swan-foot insertion as the needle entry point, avoiding damage to the patellar ligament, thereby avoiding postoperative prepatellar pain.

Description

tibial intramedullary nail

technical field

The invention relates to an orthopedic internal fixation device, in particular to an intramedullary nail.

Background technique

The tibial intramedullary nail is an internal fixation device used to treat tibial shaft fractures. Currently, the tibial intramedullary nails on the market are implanted via the upper border of the tibial tubercle of the patellar ligament, resulting in a fracture of the patellar ligament and adjacent soft tissues. Injuries, postoperative adhesions and other aseptic inflammation, the disadvantage of this surgical technique is that the patient has stubborn anterior patellar pain after the operation. In addition, if the operator does not operate properly, the tail screw will be higher than the cortical bone, which will also stimulate the soft tissue around the patellar tendon and cause pain, seriously affecting the patient's quality of life.

Contents of the invention

Aiming at the deficiency of existing intramedullary nails, the present invention provides an anteromedial approach tibial intramedullary nail, which uses the inner edge of the patellar tendon and the upper edge of the tibial swan foot as the insertion point of the intramedullary nail to avoid Damage to the patellar ligament, thereby avoiding the occurrence of prepatellar pain in patients with tibial fractures.

The technical scheme that solves the above-mentioned technical problem is:

The tibial intramedullary nail of the present invention comprises a proximal end L1 and a distal end L2 adapted to be inserted into the medullary cavity, and the included angle a between the center line of the proximal end and the longitudinal axis of the intramedullary nail is 18°-22°.

Preferably, the included angle a between the proximal centerline of the tibial intramedullary nail of the present invention and the longitudinal axis of the intramedullary nail is 20°.

Preferably, there is a transition arc section between the proximal end and the distal end of the tibial intramedullary nail of the present invention, and the radius of curvature R1 is 50 mm.

Preferably, the distal end of the tibial intramedullary nail of the present invention includes a distal upper section m near the proximal end and a distal lower section n away from the proximal end, and the angle b between the centerline of the distal upper section and the centerline of the distal lower section 0°-4°.

Preferably, there is a transition arc section between the distal upper segment m and the distal lower segment n of the tibial intramedullary nail of the present invention, and the radius of curvature R2 is 1500 mm.

Preferably, the proximal end of the tibial intramedullary nail of the present invention further includes at least one locking hole, and the included angle c between the centerline of the locking hole and the centerline of the proximal end on the plane where the centerlines of the proximal end and the distal end of the intramedullary nail are located is 80° °.

Preferably, the proximal end of the tibial intramedullary nail of the present invention further includes at least one pressure hole, and the angle d between the centerline of the pressure hole and the plane where the proximal and distal centerlines of the intramedullary nail are located is 30°.

Preferably, the distal end of the tibial intramedullary nail of the present invention includes at least two locking holes, and the projection of the centerlines of the two distal locking holes on the cross-section of the intramedullary nail and the plane where the centerlines of the proximal end and the distal end are located The sum of the included angles e and f is greater than 0° and less than or equal to 90°.

Compared with the existing tibial intramedullary nail, the anteromedial approach tibial intramedullary nail provided by the present invention can select the inner edge of the patellar tendon and the upper edge of the tibial swan foot insertion point as the insertion point of the intramedullary nail during implantation, so that The needle entry point and the proximal end of the intramedullary nail avoid the patellar ligament, avoiding damage to the patellar ligament, thereby avoiding postoperative prepatellar pain. The tibial intramedullary nail of the invention has reasonable structure and excellent performance, can be well matched with the tibial medullary cavity, and can effectively treat tibial fractures and improve the patient's quality of life.

Description of drawings

Fig. 1 is the front view of tibial intramedullary nail of the present invention;

Fig. 2 is the sectional view of Fig. 1;

Fig. 3 is a sectional view along the line A-A of Fig. 1;

Fig. 4 is along the B-B line of Fig. 1 and the C-C line sectional view;

The markings in the figure are explained as follows:

1-proximal, 2-distal, 3-proximal locking hole, 4-proximal pressure hole, 5-distal locking hole. the

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described below in conjunction with the accompanying drawings. The specific embodiments described here are only used to explain the present invention, not to limit the present invention.

As shown in Figure 1, the anteromedial approach tibial intramedullary nail of the present invention includes a proximal end 1 and a distal end 2 suitable for insertion into the medullary cavity. part of the length of L2. The angle a between the centerline of the proximal end 1 and the longitudinal axis of the intramedullary nail is 18°-22°. The longitudinal axis of the intramedullary nail refers to the Z axis along the vertical direction passing through the distal end of the intramedullary nail in Figure 1, and the center line refers to the line along the axial direction of the intramedullary nail. In a preferred embodiment, the angle a between the centerline of the proximal end 1 and the longitudinal axis of the intramedullary nail is 20°. In addition, the distal end 2 also includes a distal upper section m close to the proximal end 1 and a distal lower section n far away from the proximal end 1, and the angle b between the centerline of the distal upper section m and the centerline of the distal lower section n is 0 °-4°. The proximal end 1 and the distal end 2 of the intramedullary nail of the present invention have a transitional arc section, the arc curvature radius R1 is 50mm, the distal upper segment m near the proximal end 1 on the distal end 2 and the distal lower segment n away from the proximal end 1 It is also possible to have a transition arc section, the radius of curvature R2 of the arc is 1500mm. The diameter Φd of the proximal end 1 is 11.5mm or 13mm. The whole intramedullary nail is hollow or solid. The design of this structure conforms to the anatomical features of the tibial medullary cavity and can be well matched with the tibial medullary cavity. In particular, the design of this angle ensures the anteromedial approach of the intramedullary nail between the inner edge of the patellar tendon and the upper edge of the tibial anterior insertion, which can effectively avoid postoperative prepatellar pain and improve the quality of life of the patient.

As shown in FIG. 2 , according to different characteristics of bone structure and bone tissue, the proximal end 1 of the tibial intramedullary nail of the present invention also includes one or more locking holes 3 and one or more pressurizing holes 4 . The centerlines of the proximal end 1 and the distal end 2 are on a plane, and this plane is taken as the anatomical plane of the intramedullary nail. The included angle c between the centerline of the proximal locking hole 3 and the proximal centerline on the anatomical plane of the intramedullary nail is 80°. As shown in FIG. 3 , the included angle d between the central line of the proximal pressure hole 4 and the anatomical plane of the intramedullary nail is 30°. The angle design of the proximal locking hole and the proximal pressurizing hole can better realize the proximal cross locking and better fix the fracture end.

As shown in Figure 4, the number of distal locking holes 5 of the tibial intramedullary nail of the present invention is at least 2, wherein the projection of any two distal locking holes 5 on the cross section of the intramedullary nail is consistent with that of the intramedullary nail. The sum of the included angles e and f of the anatomical plane is greater than 0° and less than or equal to 90°. This structural design can achieve better cross-locking of the distal end of the intramedullary nail, so that the fracture end can be well fixed.

In addition, the anteromedial approach tibial intramedullary nail of the present invention may have an included angle between the center line of the proximal end 1 of the intramedullary nail and the longitudinal axis of the intramedullary nail, and its proximal and distal parts are linear structures, There is no bending; there may also be an angle between the centerline of the proximal end 1 of the intramedullary nail and the longitudinal axis of the intramedullary nail, and the distal part of the nail is an arc-shaped structure matching the medullary cavity as a whole.

Compared with the existing tibial intramedullary nail, the anteromedial approach tibial intramedullary nail provided by the present invention can realize that the inner edge of the patellar tendon and the upper edge of the tibial swan's foot insertion point can be selected as the front of the intramedullary nail insertion point during implantation. The medial approach allows the needle entry point and the proximal end of the intramedullary nail to avoid the patellar ligament, avoiding damage to the patellar ligament, thereby avoiding postoperative prepatellar pain, which is of great significance for improving the quality of life of patients.

Claims (9)

1. A tibial intramedullary nail, comprising a proximal end L1 (1) and a distal end L2 (2) suitable for insertion into the medullary cavity, characterized in that the centerline of the proximal end (1) is aligned with the longitudinal direction of the intramedullary nail. The angle a between the axes is 18°-22°. 2. The tibial intramedullary nail according to claim 1, characterized in that the angle a between the centerline of the proximal end (1) and the longitudinal axis of the intramedullary nail is 20°. 3. The tibial intramedullary nail according to claim 1, characterized in that there is a transition arc section between the proximal end (1) and the distal end (2), and the curvature radius R1 is 50 mm. 4. The tibial intramedullary nail according to claim 1, 2 or 3, characterized in that, the distal end (2) includes a distal upper segment m close to the proximal end (1) and a distal end segment far away from the proximal end (1). The lower segment n, the angle b between the center line of the upper segment of the distal end and the lower segment of the distal end is 0°-4°. 5 . The tibial intramedullary nail according to claim 4 , wherein there is a transition arc section between the distal upper segment m and the distal lower segment n, and the radius of curvature R2 is 1500 mm. 6. The tibial intramedullary nail according to claim 1, 2 or 3, characterized in that, the proximal end (1) includes at least one locking hole (3), and the centerline of the locking hole and the centerline of the proximal end (1) The included angle c between the planes where the centerlines of the proximal end and the distal end are located is 80°. 7. The tibial intramedullary nail according to claim 1 or 2, characterized in that, the proximal end (1) further comprises at least one pressure hole (4), and the center line of the pressure hole is connected to the center of the proximal end and the distal end. The angle d between the planes where the lines lie is 30°. 8. The tibial intramedullary nail according to claim 1, characterized in that, the distal end comprises at least two distal locking holes (5). 9. The tibial intramedullary nail according to claim 8, characterized in that the projection of the centerlines of the two distal locking holes (5) on the cross-section of the intramedullary nail is the same as the proximal and distal centerlines The sum of the included angles e and f of the surface is greater than 0° and less than or equal to 90°.

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