RU59398U1 - Awl for closed intramedullary osteosynthesis - Google Patents

Abstract

The utility model is aimed at ensuring the accuracy of hole formation and the possibility of opening the bone marrow canal in any departments of the tibia and femur. The specified technical result is achieved in that the cutting part of the awl is cannulated to the size of the spokes and has an asymmetric shape.

Description

The utility model relates to medicine, namely to traumatology, and can be used when performing intraosseous osteosynthesis of the femur and tibia to open the bone marrow canal.

A known tool - an awl - for forming a hole in the proximal tibia or femur for the subsequent introduction of an intramedullary nail. (M.E. Muller, M. Allgover, R. Schneider, X. Willinegger, Manual on internal osteosynthesis, Methodology recommended by the AO group, Switzerland, AdMarginem, 1996, 298-299 fig. 4.7a). The awl has a cutting part for forming a hole and a curved one in the form of a handle. Shyla has two varieties, large and small.

However, the awl is not always possible to effectively use to form a canal in the bone, in particular, it is inconvenient to use it in obese people, as well as when opening the marrow canal in the proximal or distal parts of the tibia and femur. Possibly inaccurate positioning of the awl or even its slipping from the correct point defined on the bone, with the application of force to it, which leads to the formation of a hole away from the desired position. This can lead to skewing and jamming of the intramedullary nail inserted further, with bone splitting. In addition, the diameter of the formed hole may not be sufficient for the selected type of intramedullary retainer, which often has an expanded metaphysical part, which will require further expansion of the hole with other tools.

The technical task is to ensure the accuracy of hole formation and the possibility of opening the bone marrow canal in any departments of the tibia and femur.

To solve the problem in the awl for closed intramedullary osteosynthesis with a cutting part and a curved part in the form of a handle for transmitting force, according to the technical solution, the cutting part of the awl is cannulated to the size of a spoke and made asymmetrically.

The cannulated cutting part of the proposed awl allows you to accurately set the awl at the intended point of the bone, introducing it along the spoke, and open the channel, eliminating the possibility of slipping the awl from the bone with the application of force. The formation of the hole thereby occurs in a precisely designated place. But it is not always possible to accurately draw the needle to the intended point, especially in the femur (insertion at an acute angle to the segment axis, a large array of soft tissues, the needles slip), therefore the asymmetric shape of the awl cutting part allows you to form the hole as accurately as possible, turning the awl to the necessary side . The size of the bent part of the awl was determined by the author empirically, which is confirmed by the convenience of the clinical use of the awl not only on the tibia, but also on the femur, in patients with both normal and large builds or suffering from obesity. In addition, the proposed awl can open the bone marrow canal and form a hole in the bones both in the proximal section with the antegrade introduction of the intramedullary rod through the greater trochanter and pear-shaped fossa, and in the distal section with the retrograde introduction of the rod Erez intercondylar fossa.

Thus, the proposed awl provides the maximum accuracy of hole formation when opening the bone marrow canal at the intended point, in addition, the awl is universal and can be used to open the canal of the femur and tibia with any introduction of the intramedullary rods.

Figure 1 shows the awl for closed intramedullary osteosynthesis: A - prototype (small size) and the inventive awl;

B - the cutting part of the inventive sew for closed intramedullary osteosynthesis.

Figure 2 - photo from the image intensifier tube: the proximal femur with the inserted spoke: A - face; B - profile.

The awl for closed intramedullary osteosynthesis has a cannulated cutting part 1 under the spoke, a straight line 2 and a curved part 3 in the form of a handle. The cutting part is made asymmetric in shape. The awl has three types of sizes 13, 15 and 18 mm in diameter.

An awl is used as follows.

In the tibia or femur, depending on the type of fracture, the entry point of the intramedullary nail is indicated, for which, through a small incision in the skin and soft tissue, a spoke 4 with a diameter of 2 mm is inserted into the bone. After confirming the correct position of the knitting needle, an awl is introduced radiologically along it, a hole in the bone is formed by rotational movements and the bone marrow canal is opened with the cutting part. An intramedullary shaft is inserted through the formed hole (if necessary, expand the hole for a different size of the intramedullary nail using a larger diameter awl). The increased size of the inventive awl (in comparison with the prototype is almost 2 times larger) ensures the convenience of its use when performing intramedullary osteosynthesis in patients with both normal and large addition or in patients suffering from obesity, as well as when opening the marrow canal as in the proximal section with the anthegrad introduction of the intramedullary rod through the greater trochanter and pear-shaped fossa, and in the distal section with the retrograde insertion of the rod through the intercondylar fossa.

In cases where it was not possible to enter the spoke exactly at the desired point, by turning the awl, the asymmetrically located cutting part is shifted in the necessary direction and the hole is formed eccentrically with respect to the spoke (rotational-translational motion is used).

Clinical example. Patient M. was admitted to the clinic of the Institute with a fracture in the in / 3 of the femur.

Performed closed intramedullary osteosynthesis using the awl of the proposed design. Coalescence occurred 6 months after osteosynthesis.

Figure 3 presents a photo of the introduction of a cannulated awl along the guide needle into the proximal femur; Figure 4 presents the intraoperative radiograph.

With osteosynthesis, the awl ensures the accuracy of the hole formation during the opening of the bone marrow canal and can be used for intraosseous osteosynthesis of the femur and tibia.

Claims (1)

Awl for closed intramedullary osteosynthesis, having a cutting and curved parts, characterized in that the cutting part of the awl is cannulated to the size of a spoke and has an asymmetric shape.