LV12268B - Knee endoprosthesis - Google Patents

Abstract

The described construction of the knee joint endo-prosthesis is possible for use without acrylic cement. There is a swing joint of juniper in the prosthesis and a shin prosthesis head in the form of a bar, which is in contact with a thigh prosthesis fork. The longitudinal walls of the shin head form the backing for the thigh prosthesis fork, while the cross walls of the shin head are truncated in the shape of an angle.

Description

The invention relates to medicine, in particular to reconstructive surgery, and is intended for total endoprosthesis of the knee joint.

Knee joint - Moving joint of femur and tibia. The walking process determines: on one hand the bending - bending motion of the joint, on the other hand its support (stamina). The most common form of knee joint pathology is various lesions and injuries. In 40% of cases, knee injuries are marked by purulent complications leading to joint osteoarthritis and empyema. After various inflammatory processes (rheumatoid, gonorrhea, arthritis, etc.), ankylosis of the joint may occur after injury. Note joint adhesion of joints with severe joint surface damage.

In this case, a joint resection is performed with an endoprosthetic. The most common indicators for knee joint replacement are rheumatoid polyarthritis and joint arthrosis.

In endoprosthesis, the joint is replaced with metal or metal polymer prostheses. In case of major knee injury, total articular endoprosthesis (1,2,3,4) is used.

The knee joint endoprosthesis consists of an articulated joint comprising the upper (thigh) and lower (lower) joints. The endoprosthesis contains long rods which are introduced into the femur and femur bone tunnel of the femur.

For attaching the thigh joint elements, the front and side plates are interconnected by a latch and screws.

Modern prostheses have a metal polymer mobility unit that provides bending - bending movements. The endoprosthesis and postoperative period (after 1-2 months) test the prosthesis support and flexion-flexion amplitude. The indicated endoprostheses are analogs of the invention.

Total endoprostheses are fixed to the bone with acrylic cement. It is inserted into the femoral canal of the femur and tibia and inserted into the endoprosthesis rods. After 10 to 12 minutes after mixing the components, the acrylic agent completely polymerizes to a solid state.

-2In the postoperative period, inflammatory process, thrombophlebitis, etc. may occur. development. Entering prosthetic rods into the bone marrow canal can cause purulent bone inflammation, requiring urgent bone cavity repair. Broad bone in the trepan, resulting in a bone defect, which requires bone plastic.

The most common cause is endoprosthetic instability (bone movement). This complication is observed in all surgeons after 2-5-8 years. A special device (5,6) has been developed to increase endoprosthesis fixation stability. However, even with it, endoprosthesis moves into the bone after a short time.

So-called endoprosthesis fatigue fractures are possible.In the event of an instability of the prosthesis, it is replaced by a new one. When replacing the prosthesis, acrylic cement must be removed from the femoral conduits of the femur and tibia.

Removing acrylic cement causes complications that lead to bone damage. Endoprosthesis replacement is a severe, traumatic operation involving scars, bone adhesions and metallosis. It is associated with high blood loss and is long lasting.

The closest invention to its technical solution is the N.Link knee joint endoprosthesis (7). It is a prototype of the invention. This endoprosthesis contains the femur and lower leg joints in the form of a pivot joint that looks like a fork (thigh) that covers the spine (lower leg). Plank serves as a flat base, provided with a support area with recesses for the thigh (fork) joints and secured along their contours with front and two side plates by means of latch and screws. The prosthesis has a metal polymer movement unit that provides bending - bending movements.

The basic structures of the prosthesis are made of metal. Endoprosthesis fixation involves the use of long metal rods introduced into the femoral and tibial bone marrow ducts. The bars are fixed to the bone with acrylic cement. Despite the sophisticated design of modern endoprostheses and the use of new polymer materials and technologies, all of them are characterized by postoperative complications such as inflammatory processes with osteomyelitis, which require urgent bone cavity repair.

-3The movement of the endoprosthesis is common and requires replacement of the endoprosthesis - a severe and traumatic operation.

Because of the complications described, using known endoprosthesis constructs, it became necessary to guide the design of the knee joint endoprosthesis to avoid postoperative complications such as inflammation or endoprosthesis movement.

The new design of the prosthesis must have good support strength and a vertical positioning of the lower and thigh prosthesis with optimum flexion-flexion amplitude. The creation of a new design knee joint prosthesis became an object of the invention.

The set goal is achieved by making the knee joint prosthesis in the form of a pivot joint, a fork-like, spine-containing, thigh-lower-hip joint prosthesis, the proximal prosthetic prosthesis being made in the form of a conical bar with a raised head to the forefoot, , the head is provided with recesses and openings on the end surface of the thigh prosthesis, forming a T - shaped profile of the head in cross - section, the longitudinal walls of the recess forming a support for the thigh prosthesis, providing vertical positioning of the prosthesis on one axis; rotation in relation to the lower leg prosthesis bar shall be not less than 135 ° and all parts of the prosthesis shall be made of a beam.

As the experimental studies have shown, the T - shaped profile of the shin head allows for a significant strengthening of the support strength of the two (shin and thigh) prosthesis components. For similar purposes, the cavity longitudinal walls along the sides of the shin head, where the thigh prosthetic fork is inserted, also serve a similar purpose.

Changing the shape of said shin head leads to a decrease and deterioration of the knee joint endoprosthesis, and changes the position of the shin and thigh prosthesis on one axis. The transverse walls of the lower leg prosthesis head shall be angled. As shown

-4-experimental studies to achieve optimal amplitude of flexion-flexion movements in the iliac joint endoprosthesis require that the transverse walls of the shin prosthesis head are inclined at least 135 °.

All parts of the prosthesis must be made of a pod to avoid instability of the endoprosthesis and the development of an inflammatory process in the postoperative period.

BRIEF DESCRIPTION OF THE DRAWINGS The drawings which illustrate:

fig. 1 - endoprosthesis of the knee joint (joint prosthesis, general view);

Fig. 2 - same (section A - A).

The knee joint endoprosthesis comprises: shin bone prosthesis 1 and thigh bone prosthesis 2, which are connected to each other by a pivot via an axis 3. The thigh prosthesis is made in the form of a fork 4 in the contact area with the lower thigh prosthesis. The thigh fork 4 ends with a bar 5 which is inserted into the thigh bone canal.

The shin prosthesis is made in the form of a tapered bar 6 with a raised head 7, the head being provided with recesses 8 with openings on the end surface of the shin prosthesis forming a T - shaped profile of the head in cross section. The longitudinal walls 9 of the recesses form a support for the thigh prosthesis fork, providing vertical positioning of the prosthesis on one axis. Cavity partitions 10 angled, providing thigh fork rotation with an angle of not less than 135 ° to the lower leg prosthesis bar · All prosthetic parts are made of peg.

An example of an artificial knee replacement prosthesis in an experiment is given.

To perform rabbit knee replacement surgery, a rabbit knee replacement prosthesis was made.

The rabbits lay down on the operating table, fixing all the limbs. A layer of biological adhesive is sprayed onto the intended cut area. In intraperitoneal anesthesia, a side incision of 8 cm is made along the knee joint. Cover the wound with gauze salveo.

-5Relax your muscles. It cuts the film of bone, cuts the tibia and femur, preserving the main nerves and blood vessels. The drill forms a channel in the shinbone of the shinbone, preparing the channel for the introduction of shin bone prosthesis 1, 6.

First, the tibial component of the endoprosthetic shin is installed. A drill is used to form a canal in the thigh - preparing a canal for the introduction of the femur 2 of the thigh bone prosthesis 2. The two parts of the prosthesis are opposed by connecting the femoral prosthetic fork 4 to the lower prosthetic denture head 7. Place the femoral prosthetic fork 4 along the lower prosthetic dentures 8, ensuring correct placement of both endoprosthetic parts (lower leg and thigh). The two parts of the endoprosthesis are connected in the form of a pivot by means of the axis 3. The amplitude of flexion-flexion in the joint and its supporting capacity (stamina) are checked. If necessary, adjust the condition of the endoprosthesis. The wound is sutured sequentially by topical administration of antibiotics. Apply plaster bandage.

All knee joint endoprosthesis elements are made of paegel. The torso and thigh bones are provided with multiple perforation openings that allow the artificial joints to contact the surrounding tissues.

11 experiments were performed on rabbits - knee replacement surgery. The amount of movement in the artificial knee joint was restored after 3 weeks. Joints began to form after 4 weeks. The intra-articular fluid was detected after 2 months. The joints are fully formed after 7-8 months. The surfaces of the artificial shin of the lower leg and the fork of the femur were polished.

Histological studies showed that blood vessels and bone tissue cells grow in the perforation of the prosthesis, forming osteons.

In none of the 11 cases of the knee replacement endoprosthesis experiment did motion, purulence, or rejection of the artificial knee joint be observed. The duration of observation in the rabbit experiment was 1 year 7 months, which corresponds to 15 years of human observation.

-6Specific growth of blood vessels and tissues from bone structure segments in the small perforations of the epiglottis, in animals for 2-3 weeks, in man for 4-5 months. In this way, the physiological fixation of the artificial knee joint in the bone tissue of the body occurs, which excludes the use of acrylic cement in the prosthetic process.

Pellet wood is easy to process and allows the endoprosthesis to be adjusted directly during surgery.

SOURCES OF INFORMATION

1. K.M.Sivash, B.P.Morozov.

Endoprosthesis of the knee joint. Orthopedics and Traumatology, No. 6, 1978, 6 pages.

2. KF Patent No. 2045248, A61F 2/38, publ.IB, No.28, 1995, 122 pages.

3. KF Patent No. 2043090, AS1F 2/38, publ.IB, No. 25, 1995, p. 108.

4. European patent EP no. - 450 - 121, A51F 2/38, publ.European Patent Bulletin, No.41,1991, p.20.

5. A.apl.No.162343, A61F 2/38 publ.IB, no.4,

1991, p.

6. International Patent Publication No. WO / 91/06262, published in Gazette PCT, No. 11, 1991, p.

7. W.Link firm knee joint prosthesis

I.A.Movshovich's book Operative Orthopedics,

M. Med. 1994, 305-309.

Claims (1)

INVENTION FORMULA Knee joint endoprosthesis in the form of a pivot joint, a fork-like, spherical, lower leg and femoral prosthetic part characterized in that the proximal prosthetic prosthesis is made of a conical bar with a raised head, with a toothed tooth and a fork tooth, and openings on the upper surface of the thigh prosthesis forming a T - shaped profile of the head in cross section, the longitudinal walls of the cavity forming a support for the thigh prosthesis fork, providing vertical positioning of the prosthesis on one axis; at an angle of not less than 135 °, all parts of the prosthesis shall be made of a beam.