CN1119126C - bone plate - Google Patents

Abstract

The bone plate is provided with holes (2) arranged in the direction of the longitudinal axis (1) of the plate for receiving bone screws. The diameter D of at least one hole (2) measured in the direction of the longitudinal axis (1) of the plate_LLarger than the diameter D of the hole (2) measured perpendicular to the longitudinal axis (1) of the plate_Q. These have a smaller diameter D perpendicular to the longitudinal axis (1) of the plate_QAt least one of the holes (2) in which the diameter D is_QThe region is provided with a partial thread (3) for mounting a bone screw with a threaded head.

Description

bone plate

The invention relates to a bone plate.

A bone plate is known from FR 742.618, in which the circular hole in the plate is inclined relative to the normal direction of the plate and is internally threaded. These circular holes allow the insertion of bone screws having a second threaded portion which is enlarged compared to the threaded conventional screw shank portion and which fits into the internally threaded hole in the plate. Due to the inclination of the plate hole, it is also possible to fix the bone screw in the bone with the specified inclination of the plate hole.

The disadvantage of this known bone plate is that the inclination of the bone screw cannot be selected arbitrarily, but is predetermined by the inclination of the plate hole and the internal thread formed in the plate hole.

The present invention successfully overcomes this disadvantage. The object of the present invention is to provide a bone plate whose holes are designed so that it is possible to select two different types of screw fixation. In the first type of use, the bone screw with the spherical head is in the elongated hole of the plate and can be screwed into the bone at an angle relative to the normal of the plate within a selectable range. The effect of pressurization can also be produced by the inclination of the plate hole spot facing.

In the second type of use, a bone screw with a threaded head acts as a strut screw, screwed into the local thread of the elongated hole, and can be screwed to the plate vertically and in a rigid manner.

To achieve the above object, according to the present invention, a bone plate is provided, which has some holes arranged along the longitudinal axis of the plate, and the holes are used for installing bone screws, and is characterized by: A) at least one hole, which is measured along the longitudinal axis of the plate diameter D _L greater than the diameter D _Q of the hole measured perpendicular to the longitudinal axis of the plate; B) at least one of these holes having a smaller diameter D _Q perpendicular to the longitudinal axis of the plate is made in an area of diameter D _Q Partially threaded for mounting a bone screw with a threaded head.

Adopt the advantage that the present invention obtains to be mainly in, can be used in various application occasions (fixation, compression, as internal fixator (Fixateur interne) in the sense of prop screw) according to the osteosynthesis plate of the present invention universally , but especially in the maxillofacial area, where three-dimensional adaptability is of particular importance.

Other advantages of the present invention are as follows:

- Compatibility with conventional cortical screws (Kortikalisschrauben);

- Possibility of the bone screw to change angles within the plate hole;

- Possibility to remove the screw without difficulty even via an intraoral channel;

- Possibility of reoperation with a new plate;

- Bone screw heads in common diameters can be secured in plate holes; and

- The effect of compression can be implemented by means of ball head screws.

The invention and further developments of the invention are explained in more detail below with the aid of a partially schematically represented exemplary embodiment.

in:

Fig. 1 is according to the partial perspective view of bone plate of the present invention;

Figure 2 is a partial top view of the bone plate of the present invention;

Fig. 3 is a partial longitudinal section through the bone plate along the line III-III of Fig. 2;

Fig. 4 is a cross-section perpendicular to the longitudinal direction of the bone plate along the line IV-IV of Fig. 2;

Fig. 5 passes through bone plate according to the present invention and is screwed into the partial longitudinal section of the bone screw with double thread vertically;

6 is a partial longitudinal section through a bone plate according to the invention and a bone screw that passes obliquely or vertically, this bone screw has a spherical head and serves as a non-pressurized fixation screw;

Figure 7 is a transverse section perpendicular to the longitudinal section according to Figure 6 in the region of the bone plate hole; and

FIG. 8 is a partial longitudinal section through a bone plate according to the invention and a vertically penetrating bone screw, which has a spherical head and acts as a clamping screw with compression.

The bone plate shown in Figure 1 has holes 2 arranged along the longitudinal axis 1 of the plate for mounting (shown in Figures 5 and 6) different types of bone screws 6 and 7, which are used to attach the bone plate fixed on the bone.

As shown in detail in FIGS. 2-4, the holes 2 are designed as so-called slotted holes, in other words the diameter _DL measured along the longitudinal axis 1 of the plate is greater than the diameter _DQ perpendicular to the longitudinal axis 1 of the plate.

As shown in Figure 4, the hole 2 faces the lower part of the bone-using surface 4, and is designed to be approximately cylindrical along the transverse direction of the plate, while as shown in Figure 3, it is expanded into an approximately cylindrical shape along the longitudinal direction of the plate toward the bone-using surface 4. in the cone. The cylindrical part of hole 2 is shaped on internal thread 3, because the structural condition of hole, so internal thread 3 only respectively extends an angle range about 60 °-179 ° on both sides of the plate, preferably about 90 °-150 °.

As shown in FIG. 5 , this partial internal thread is used to accommodate a bone screw 6 with a threaded head 9 . By tightening the external thread of the threaded head 9 with the matching (partial) internal thread 3, a rigid fixation between the bone screw 6 and the plate is achieved. This tightened bone screw 6 acts as a strut screw.

The upper part of the hole 2 facing away from the bone-contacting surface 4 is designed to be elliptical, and is shaped on a conical flare 5, as shown in Figures 6 and 7, this conical flare 5 is used to slidably pack into the ball shape Head 8 of bone screw 7 . In this case, "bone-using surface 4" is to be understood as the surface of the plate which is substantially in direct contact with the bone.

Similar to Figures 6 and 7, Figure 8 shows a bone plate with a bone screw 7 having a spherical head 8, indicated by an arrow 10 in which the plate can perform a compressive action. For this purpose, as shown in Figure 3, the conical flaring 5 of the hole 2 can be processed by spherical or bevel milling to an angle of 57° relative to the longitudinal axis 1 of the plate, so that the long hole made has a leading slope to the bone screw 7 role.

This particular geometry of the hole 2 allows the option of using different types of bone screws 6, 7 on the same plate.

According to the invention, at least one of the holes with the smaller diameter _DQ has, in its upper part facing away from the bone contacting surface, a concave flare for receiving a bone screw with a spherical head. The concave flare is a spherical or conical flare. The ratio D _L /D _Q is in the range of 1.01-3.00. The ratio D _L /D _Q is in the range of 1.1-1.5.

Claims (5)

1. blade plate, it has some along holes (2) that plate longitudinal axis (1) direction is arranged, and hole (2) are used to install bone screw, it is characterized by:

A) at least one hole (2), it is along the diameter D of plate longitudinal axis (1) orientation measurement _L, greater than the diameter D of this hole (2) edge perpendicular to plate longitudinal axis (1) orientation measurement _Q

B) have than minor diameter D perpendicular to plate longitudinal axis (1) _QThese holes (2) at least one, be D at diameter _QThe zone in be shaped on partial screw threads (3), be used to install the bone screw of a threaded head.

2. according to the described blade plate of claim 1, it is characterized by: have than minor diameter D _QHole (2) at least one, on its top, a recessed enlarging (5) is arranged back to bone contact surface (4), be used to install the bone screw of a band ballhead.

3. according to the described blade plate of claim 1, it is characterized by, described recessed enlarging (5) is sphere or taper enlarging.

4. according to claim 1 or 2 described blade plates, it is characterized by: ratio D _L/ D _QIn the scope of 1.01-3.00.

5. according to the described blade plate of claim 4, it is characterized by: ratio D _L/ D _QIn the 1.1-1.5 scope.

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