RU2042345C1 - Total endoprosthesis of femur - Google Patents

Abstract

FIELD: medicine; traumatology; orthopedics. SUBSTANCE: endoprosthesis has cup 1 with fastening teeth 2 and ring-shaped groove 3 for locking washer 4 and window for its installation. Head 6 is inside cup 1 to form a spheric hinge. Head 6 is connected with pedicle 8 through neck 7. Pedicle 8 is made in the form of telescopic threaded joint having rod 9 and bushing 11. Bushing 11 is connected with hinge 12 forming flat knuckle joint with hinges 14 and 15. Hinges 14 and 15 are connected with base 16, bearing plate 17 and crural pedicle 18 having conic shape and step-like cylindric grooves. EFFECT: enhanced effectiveness in restoring locomotor function. 6 cl

Description

 The invention relates to medical equipment and can be used in traumatology and orthopedics with complete damage to the femur.

 Known adopted for the prototype endoprosthesis containing a cup with teeth of attachment, head, neck and leg.

 However, this endoprosthesis is non-separable and does not provide sufficiently stable fixation of the leg.

 Also known is an endoprosthesis containing a head, neck and leg (Yumashev G. S. Traumatology and orthopedics, M. Medicine, 1983, p. 76), adopted as the base object.

 However, this endoprosthesis retains the same disadvantages as the prototype, and in addition, it is not applicable for the pathology of the acetabulum and the need for a complete replacement of the femur.

 The purpose of the invention is to ensure collapsibility, the possibility of complete replacement of the femur, eliminating the likelihood of self-dissection of the hinges of the endoprosthesis and instability of the legs with the possibility of correction of the articular distance and the relative position of their axes.

 The goal is achieved by the fact that in the joints of the endoprosthesis a rigid lock is used that does not require locking, the femoral leg is rotationally sliding, and the tibial leg is made stepwise conical.

 The essence of the invention lies in the fact that the locks of the hinges are fastened by means of an internal circular washer, the femoral leg is made in the form of a telescopic-threaded connection, and the conical tibial leg is conical and provided with cylindrical grooves.

 In FIG. 1 shows a complete endoprosthesis assembly; figure 2 section aa in figure 1; figure 3 hip joint in two projections; figure 4 knee joint, front view (a); section (b) and side view (c); figure 5 lock washer of the hip joint; in Fig.6 lock washer of the knee joint.

 The endoprosthesis consists of a cup 1 with fixing teeth 2 and an annular groove 3 under the lock washer 4 and a window 5 for its installation.

 Inside the cup 1 there is a movable head 6, held against dismemberment by a washer 4 and forming a hip spherical hinge with cup 1.

 The head 6 is connected through a curved round neck 7 with a femoral leg 8, which is made of two parts joined telescopically with a threaded connection, consisting of a threaded pin 9 with a lock nut 10, screwed into the threaded sleeve 11.

 The sleeve 11 is seamlessly connected with the loop 12, forming with the axis 13 and loops 14 and 15 a flat knee joint.

 The loops 14 and 15 are seamlessly connected to the base 16 with a support plate 17 and a tibial leg 18, which is made conical, stepped with cylindrical grooves 19 and 20 with a diameter decreasing downward. On the conical steps 21, 22 and 23, vertical grooves 24, 25 and 26 are made.

 In their middle part, the loop 12 and the axis 13 have adjacent identical grooves 27 and 28 under the lock washer 29 with an opening 30 for the hook of the extractor (not shown).

 Washers 4 and 29 may also have a circular cross section, correspondingly shaped groove 3 and grooves 27 and 28.

 The endoprosthesis is used as follows.

 By loosening the lock nut 10 by rotating the threaded pin 9 in the sleeve 11, set the required length of the legs 8 and the relative position of the axes of the hip and knee joints. The achieved position is fixed by tightening the lock nut 10.

 In the pretreated acetabulum, the cup 1 is fixed by hammering or screwing (depending on the design of the teeth 2) 1. Leg 8 is passed through the soft tissue of the thigh, replacing the removed femur with it. In this case, the loop 12 of the knee joint extends into the region of the remote knee joint.

 Insert the head 6 into the cup 1, fix their movable position by means of a lock spring washer 4, which is pushed with a pointed end through the window 5 into the channel 3 until the pointed end enters, rounding the head 6, again into the window 5. The inner part the washer 4, which is tightly attached to the head 6, while remaining movable, is firmly articulated in the cup 1. The other end of the washer 4, provided with an opening 31 for the extractor hook (not shown), is slightly bent and, protruding from the window 5, ensures that the washer is stationary in the groove 3 and eliminates tazo self-dissection femoral hinge.

 Having drilled the bone marrow canal of the lower leg under the leg 18, the stopper from the specially treated bone or other bioinert material is lowered to the end of the channel drilled and, filling it half with paste-like bone cement, push the leg 18 into the canal so that the supporting platform 17 rests on the butt of the tibia .

 Then, after the cement has hardened, its excess, protruding from under the slab 17, is removed. Loop 12 is inserted between the loops 14 and 15 and joined with its axis 13, the position of which is fixed with a lock washer 29 inserted into the annular channel formed by the grooves 27 and 28.

 Having thus connected all the elements of the endoprosthesis with each other and the bones, the dissected soft tissues are sutured in layers and proceed to rehabilitation measures.

 If necessary, revisions of the broken elements of the endoprosthesis provide economical access to them, pull out the corresponding lock washer 4 or 29 and carry out the necessary replacement.

 The total hip endoprosthesis is intended for use in trauma and orthopedic clinics in the surgical treatment of diseases of the joints of the lower extremities.

 Its use allows you to restore limb support while damaging the femur and its hip and knee joints.

Claims (2)

 1. TOTAL HIP Endoprosthesis containing a hip joint in the form of a cup with fixing teeth and a head, a neck, a femoral leg with a latch mounted in a threaded sleeve connected to the knee joint, and a tibial leg, characterized in that the knee joint is made in the form of a central loop mounted on the end of the threaded sleeve, the axis and two side loops, integral with the base of the tibial leg, and the tibial leg is made in a conical shape, stepped, with cylindrical grooves and with vertical grooves on tapered steps.  2. The endoprosthesis according to claim 1, characterized in that the hip and knee joints are equipped with locks, the hip joint lock is made in the form of an annular groove on the inner surface of the cup at the level of the diameter of the head in which the dissected annular washer is placed, one end of which is sharpened, and on the other is made a hole, and the knee joint lock is made in the form of an annular channel formed by grooves in the central loop and the axis in which the clamp is placed, one end of which is sharpened and the other bent and has a hole.

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