CN106725818A - A kind of mould for making knee joint bone cement spacer femoral component - Google Patents

Abstract

The invention discloses a kind of mould for making knee joint bone cement spacer femoral component, two contact head die cavities are symmetrically set with the mould, two contact head die cavities are interconnected, and the upper surface of the contact head die cavity is provided with the curved surface forming face of outside depression, for forming the main curved surface contacted with tibial component.Replace making knee joint bone cement spacer femoral component by hand by formed in mould mode, rapid shaping shortens operating time.Reduce and make in bone cement femoral component operating process to the dependence of doctors experience.The spacer femoral component highly similar to former artificial knee joint prosthesis can be produced, the installation accuracy on subjects bones, a certain degree of secondary injury reduced to patient is improved.The formed precision of two main curved surfaces is effectively ensured, the part of spacer two can be allowed to realize that preferably motion coordinates.

Description

A mold for making a bone cement spacer femoral component of the knee joint

technical field

The invention relates to the field of medical instruments, in particular to a mold for making a knee joint bone cement spacer femoral component.

Background technique

At present, knee replacement surgery is more and more widely used in the treatment of knee lesions. However, undesired loosening of the artificial endoprosthesis occurs before the end of the usual useful life. This can involve septic or aseptic loosening. Aseptic looseness means no microbial bacteria have been detected. There are many reasons for aseptic loosening. Aseptic loosening usually involves wear at the sliding surfaces of artificial endoprostheses. The loosening process of septic loosening is induced by microbial bacteria. Depending on when it appears, it can be an early or late infection. Septic loosening is a very serious disease for the patient and its treatment is very expensive. In both cases of aseptic and septic loosening, revision surgery is usually performed as well. This can be done as a one-stage or two-stage revision surgery.

For septic loosening, two-stage revision surgery is common. In a two-stage revision surgery, the infected prosthetic endoprosthesis is removed in the first procedure, followed by debridement to remove the infected tissue and insertion of a temporary space-occupying stent called a spacer. The spacer occupies the space previously occupied by the revised endoprosthesis until the emerging infection has resolved. In order to effectively prevent muscle atrophy during this period, and to stabilize the existing resection situation, the spacer function is very important. Articulating spacers replicate the function of the joint and allow a degree of mobility in the affected limb, which allows the patient to move earlier. The spacer was removed at the second surgery, and another debridement was performed before implantation of a cemented or cementless revision joint endosseous prosthesis.

Knee spacers typically include two components, a tibial component and a femoral component. In the prior art, the doctor manually kneads a matching bone cement spacer that is similar in appearance and geometric size according to the shape of the patient's prosthesis during the operation, and is used as a substitute for the original artificial prosthesis.

However, hand-kneading the spacer during the operation requires prolonging the operation time, increasing the pain of the patient and increasing the risk of the operation. The hand-kneaded bone cement spacer is irregular in shape, and the matching accuracy with the patient's wound is low, which affects the treatment effect of the patient. The production quality of bone cement spacers is limited by the doctor's production experience.

Therefore, how to provide a mold for making the femoral component of the bone cement spacer of the knee joint is a technical problem to be solved by those skilled in the art.

Contents of the invention

The object of the present invention is to provide a mold for making the femoral component of the bone cement spacer of the knee joint, which improves work efficiency and precision of the component, and simplifies the operation process.

In order to solve the above-mentioned technical problems, the present invention provides a mold for making the femoral component of the bone cement spacer of the knee joint. Two contact head cavities are arranged symmetrically in the mold, and the two contact head cavities communicate with each other. , and the upper surface of the cavity of the contact head is provided with an outwardly concave curved surface forming surface for forming a main curved surface in contact with the tibial component.

Preferably, an inwardly protruding limiting groove cavity is provided between the two detection head cavities for forming a limiting groove for positioning the tibial component.

Preferably, it includes an upper mold and a lower mold, the curved molding surface is provided on the upper mold, and the lower mold is provided with a rear surface molding surface opposite to the curved molding surface.

Preferably, the rear surface molding surface protrudes inwardly.

Preferably, the upper mold includes two half molds symmetrically arranged left and right, and the two contact head cavities are respectively arranged in the two half molds.

Preferably, positioning bosses for positioning the upper die are provided at both ends of the lower die.

Preferably, demoulding slopes are provided on both sides of the lower mold.

Preferably, a discharge groove is provided on the demolding slope, and the discharge groove communicates with the cavity of the contact head.

Preferably, four discharge grooves are included, and each cavity of the contact head communicates with two discharge grooves.

Preferably, the discharge groove communicates with the bottommost end of the cavity of the contact head.

The mold for making the femoral component of the bone cement spacer of the knee joint provided by the present invention has two contact head cavities symmetrically arranged in the left and right sides of the mold, the two contact head cavities are connected to each other, and the upper surface of the contact head cavity is provided with Outwardly recessed curved contouring surface for forming the primary curve for contact with the tibial component. The femoral component of the knee joint bone cement spacer is replaced by hand-made mold forming, and the rapid prototyping shortens the operation time. The dependence on the doctor's experience in the process of making bone cemented femoral components is reduced. A spacer femoral component with a height similar to the original artificial knee prosthesis can be produced, which improves the installation accuracy on the patient's bone and reduces the secondary injury to the patient to a certain extent. Effectively guarantee the forming accuracy of the two main curved surfaces, and allow the two parts of the spacer to achieve better motion coordination.

Description of drawings

Fig. 1 is the exploded schematic diagram of a kind of embodiment of the mold provided by the present invention;

Fig. 2 is a schematic diagram of installation of a femoral component made by a specific embodiment of the mold provided by the present invention.

detailed description

The core of the invention is to provide a mold for making the femoral component of the bone cement spacer of the knee joint, which improves the working efficiency and precision of the component, and simplifies the operation process.

In order to enable those skilled in the art to better understand the solution of the present invention, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

Please refer to Fig. 1 and Fig. 2, Fig. 1 is the exploded schematic view of a kind of specific embodiment of the mold provided by the present invention; Fig. 2 is the installation schematic diagram of the femoral component that a kind of specific embodiment of the mold provided by the present invention is made .

In the mold provided by the specific embodiment of the present invention, the processed femoral component has two contact heads, and the contact head has a main curved surface 8 for contacting the tibial component. Therefore, two symmetrical contact head cavities are arranged in the mold, and the two contact head cavities communicate with each other, and the upper surface of the contact head cavity is provided with a curved surface molding surface 3 concave to the outside of the cavity for forming The convex main surface 8 that the tibial component contacts.

The femoral component of the knee joint bone cement spacer is replaced by hand-made mold forming, and the rapid prototyping shortens the operation time. The dependence on the doctor's experience in the process of making bone cemented femoral components is reduced. A spacer femoral component with a height similar to the original artificial knee prosthesis can be produced, which improves the installation accuracy on the patient's bone and reduces the secondary injury to the patient to a certain extent. Effectively guarantee the forming accuracy of the two main curved surfaces, and allow the two parts of the spacer to achieve better motion coordination.

In order to realize the positioning when connecting with the tibial component, it is necessary to set a limit groove between the two contact heads, so it is necessary to set an inwardly protruding limit groove cavity 4 between the two detection head cavities to form a positioning Retaining slot for the tibial component.

In the mold that the specific embodiment of the present invention provides, in order to facilitate taking out the parts after molding, the mold can be set as an upper mold and a lower mold 1, the curved surface forming surface 3 is arranged on the upper mold, and the lower mold 1 is provided with a curved surface forming surface 3 In order to save material, the opposite rear surface molding surface protrudes inward, so that the rear surface of the femoral component is concave forward. Specifically, the upper mold includes two half-moulds 2 symmetrically arranged left and right, and two contact head cavities are respectively arranged in the two half-moulds 2 . Middle, up, down, left, and right refer to directions in the drawings, which are used to indicate relative positions, and are not limited to them in actual use.

In order to ensure accurate positioning of the upper and lower molds, positioning bosses 5 for positioning the upper mold can be provided at both ends of the lower mold 1 for positioning the upper mold in the left and right direction of the femoral component. In order to facilitate demoulding, demoulding slopes 6 are provided on both sides of the lower mold 1, and at the same time, the front and back directions when the upper film and the lower mold 1 are fastened can be positioned. A discharge groove 7 is arranged on the demoulding slope 6, and the discharge groove 7 is connected to the cavity of the contact head. Specifically, four discharge grooves 7 may be provided, and each contact head cavity communicates with two discharge grooves 7 . The discharge groove 7 communicates with the bottom end of the cavity of the contact head. Used to discharge excess bone cement raw materials when pressing the femoral component, these discharge grooves 7 are all set at the bottom end of the geometric shape of the tibial end component, so that the two main curved surfaces 8 of the femoral component have a higher geometry Shape, and can make the excess bone cement material discharged to the external space reasonably.

The specific molding process is to fill the cavity of the two mold halves 2 with bone cement. Fill the bone cement on the cavity block of the lower mold 1 again. The two half molds 2 are pressed together with the lower mold 1, so that the femoral part of the spacer is pressed into shape.

The mold for making the femoral component of the bone cement spacer of the knee joint provided by the present invention has been introduced in detail above. In this paper, specific examples are used to illustrate the principle and implementation of the present invention, and the descriptions of the above embodiments are only used to help understand the method and core idea of the present invention. It should be pointed out that for those skilled in the art, without departing from the principle of the present invention, some improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims (10)

1. a mold for making knee joint bone cement spacer femoral component, it is characterized in that, left and right symmetry is provided with two contact head cavities in the mold, two described contact head cavities communicate with each other, and the The upper surface of the cavity of the contact head is provided with an outwardly concave curved surface forming surface (3) for forming a main curved surface (8) in contact with the tibial component. 2. The mold according to claim 1, characterized in that an inwardly protruding limiting groove cavity (4) is provided between the two detection head cavities for forming a limiting groove for positioning the tibial component . 3. mold according to claim 2, is characterized in that, comprises upper mold and lower mold (1), and described curved surface forming surface (3) is arranged on described upper mold, and described lower mold (1) is provided with The rear surface molding surface opposite to the curved molding surface (3). 4. The mold according to claim 3, wherein the rear surface molding surface protrudes inwardly. 5. mold according to claim 4, is characterized in that, described patrix comprises two half molds (2) that left and right symmetry is arranged, and two described contact head die cavities are respectively arranged on two described half molds ( 2) Inside. 6. The mold according to any one of claims 3 to 5, characterized in that, both ends of the lower mold (1) are provided with positioning bosses (5) for positioning the upper mold. 7. The mold according to claim 6, characterized in that, demoulding slopes (6) are provided on both sides of the lower mold (1). 8. The mold according to any one of claim 7, characterized in that a discharge groove (7) is arranged on the demoulding slope (6), and the discharge groove (7) communicates with the contact head type cavity. 9. The mold according to claim 8, characterized in that it comprises four discharge grooves (7), and each of the contact head cavity communicates with two discharge grooves (7). 10. The mold according to claim 9, characterized in that, the discharge groove (7) communicates with the bottommost end of the cavity of the contact head.