RU2614496C2 - Sighting device for hidden screw removal from femoral shaft - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: sighting device for hidden screws removal from the femoral shaft, including a mallet handle with a channel for drill introduction followed by milling. The difference is that it comprises a centering rod with a parallel conductor branch and a connecting mallet handle, the end of the centering rod is equipped with a V-shaped groove top for reception of a hidden screw in the femur channel, on which the conductor branch channel is focused, which is intended for sleeve with a stylet for a removable hollow drill or a removable hollow mill.

EFFECT: invention provides accurate drill and mill orientation on the axis hidden screw for its subsequent disposal during medullary canal liberation for leg prosthesis or intramedullary nail installation.

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Description

The invention relates to medicine and medical equipment, namely to traumatology and orthopedics, and can be used in surgical interventions for primary and revision hip joint replacement, in which manipulations associated with the reaming of the medullary canal are necessary.

After the fractures of the femur, the latter sometimes have screws or fragments of them [1] that intersect the lumen of the medullary canal, which impede the introduction of a reamer, rasp or trimmer, which creates serious difficulties in implanting the femoral component or revision nail during rheostosynthesis. Removing such a screw through traditional access can significantly increase the invasiveness of the operation. Even with open access, the screw may be hidden beneath the surface of the bone, which precludes accurate determination of the projection point for trepanation of the bone. The use of closed puncture access will significantly reduce additional trauma combined with the main intervention (endoprosthetics or intramedullary rheosteosynthesis), and the exact determination of the projection point of the screw axis on the bone surface will reduce the size of the hole left in the bone after the screw is removed. Currently, to determine the projection point of the screw is used EOP control by the method of "free hand" [2].

The guiding devices used both when installing an intramedullary nail and lockable screws, and when they are closed, were used as analogues of this device.

A device is known for closed retrograde blocked intramedullary osteosynthesis of femoral diaphysis fractures [3], containing a handle-arch and conductive bushings through which bone is accessed, holes are drilled into the bones and accurate fixation of holes into the holes of the fixer is achieved, so that osteosynthesis is closed and less traumatic . Similarly, the removal of the latch is carried out, which begins with the fixing of the arc handle to the end of the intramedullary shaft.

The disadvantage of this device is that with its help you can remove only the screws that block this particular nail, and the latter should be in the medullary canal. But even with this nail, it is impossible to use this device to locate the screws left in the canal, since the screws are an obstacle to the insertion of the nail into the medullary canal.

The closest in technical characteristics is a special distal guiding device for closed, blocked femoral osteosynthesis [3]. It is used in conjunction with the guiding trocar to align the center point of the guiding device with the center of the hole in the intramedullary nail to block. The device allows you to first enter a tapping tibial locking bolt, which is then replaced by a distal locking bolt, and also, using a depth gauge, allows you to enter the proximal fixing bolt [3]. The disadvantages of this device is its specialization, i.e. Applicability is only paired with the latch for which the sighting device is designed. In the absence of a special nail, it is impossible to use this device to find screws that do not extend to the surface of the bone.

The objective of the present invention is to provide a device devoid of the above disadvantages for finding hidden screws in the diaphysis of the femur with the coaxial orientation of the drill or cutter to remove them without using an electron-optical converter.

The technical result of the claimed invention consists in the exact orientation of the drill or cutter on the axis of the screw hidden in the bone for its subsequent removal when releasing the medullary canal under the installation of the endoprosthesis leg or intramedullary nail.

The device allows you to:

- to achieve low-traumatic removal from the diaphysis of the femur of the hidden, fully or partially in the medullary canal of the screws, if it is impossible to intraoperatively detect them on the surface of the bone;

- reduce the invasiveness of the operation by accurately and quickly determining the spatial position of the hidden screw in the diaphysis of the femur;

- reduce the time of the operation of total hip arthroplasty due to the rejection of the use of the image intensifier tube and, as a result, the reduction of radiation load on the surgeon, the operating team and the patient.

The result of the invention is achieved due to the fact that the device contains a centralizer rod, a parallel branch of the conductor branch and a gusset connecting them, and the end of the centralizer rod has a V-shaped groove coaxial with that made in the conductor branches by a channel into which a sleeve, mandrel and drill can be sequentially inserted to drill a hidden screw.

The illustrations show:

FIG. 1 (top view). An aiming device for removing hidden screws from the diaphysis of the femur is installed intramedullary, where 1 is the centralizer rod; 2 - femoral canal; 3 - conductor branch; 4 - handle-heel pad; 5 - groove centralizer; 6 - conductor channel; 7 - common axis (elements 6, 8, 10, 11 and passing through the center of the centralizer groove 5); 8 - removable sleeve (tissue protector); 10 - a hollow drill (mill); 11 - a hidden screw; 12 - the outer cortical layer of the femur.

Figure 2 (semi-axial projection). An aiming device for removing hidden screws from the diaphysis of the femur is installed intramedullary, where 1 is the centralizer rod; 2 - femoral canal; 3 - conductor branch; 4 - handle-heel pad; 5 - groove centralizer; 6 - conductor channel; 7 - common axis (elements 6, 8, 10, 11 and passing through the center of the centralizer groove 5); 8 - removable sleeve (tissue protector); 10 - a hollow drill (mill); 11 - a hidden screw; 12 - the outer cortical layer of the femur.

FIG. 3 (side view). Sighting device for removing hidden screws from the femoral diaphysis, installed intramedullary, where 1 is the centralizer rod; 2 - femoral canal; 3 - conductor branch; 4 - handle-heel pad; 5 - groove centralizer; 6 - conductor channel; 7 - common axis (elements 6, 8, 10, 11 and passing through the center of the centralizer groove 5); 8 - removable sleeve (tissue protector); 10 - a hollow drill (mill); 11 - a hidden screw; 12 - the outer cortical layer of the femur.

FIG. 4 (beveled projection - pseudo 3D). Sighting device for removing hidden screws from the femoral diaphysis, installed intramedullary, where 1 is the centralizer rod; 2 - femoral canal; 3 - conductor branch; 4 - handle-heel pad; 5 - groove centralizer; 6 - conductor channel; 7 - common axis (elements 6, 8, 11 and passing through the center of the centralizer groove 5); 8 - removable sleeve (tissue protector); 9 - mandrin; 11 - a hidden screw; 12 - the outer cortical layer of the femur; 13 - installed acetabular component.

FIG. 5 (beveled projection - pseudo 3D). An aiming device for removing hidden screws from the diaphysis of the femur is installed intramedullary, where 1 is the centralizer rod; 2 - femoral canal; 3 - conductor branch; 4 - handle-heel pad; 5 - groove centralizer; 6 - conductor channel; 7 - common axis (elements 6, 8, 10, 11 and passing through the center of the centralizer groove 5); 8 - removable sleeve (tissue protector); 10 - a hollow drill (mill); 11 - a hidden screw; 12 - the outer cortical layer of the femur; 13 - installed acetabular component; 14 - drill chuck.

The sighting device for removing hidden screws from the femoral diaphysis (Fig. 1) is a frame structure and contains a centralizer rod 1 for insertion into the femoral canal 2, a conductive branch 3, which 3 is parallel to the centralizer shaft 1, and the handle connecting them pad 4, designed for axial impacts on the centralizer rod 1. The end of the centralizer rod 1 has a V-shaped centralizer groove 5. The conductive branch 3 contains a conductive channel 6, the axis 7 of which is oriented to the center of the centralizer groove 5. Into the conductive channel 6introduced a removable sleeve 8 with a mandrel 9, along the axis 7 of which a hollow milling cutter 10 can be inserted into the femoral canal 2, which is oriented towards it 11 in the position of the centralizing groove 5 on the hidden screw 11. When drilling the screw in the sleeve (tissue protector) 8 have a hollow drill (cutter) 10.

This device is used during hip joint replacement surgery when a screw is found that crosses the medullary canal so that it interferes with the canal processing with rasps and the introduction of the endoprosthesis leg. Removing the hidden screw is as follows. At the stage of preparation of the femur for implantation of the femoral component, after opening the bone channel 2 to the screw 11, the centralizer rod 1 is inserted into the channel 2 and put on with the centralizing groove 5 on the body of the screw 11, if necessary, achieving a tight fit of the groove 5 on the screw 11 using hammer blows on the grip-handle 4. The latter is judged by the disappearance of the device rotations in channel 2. In this case, the conductive branch 3 is oriented to screw 11. After fixing the hidden screw 11 in the centralizing groove 5 through the drill bush 8, coaxially with the longitudinalwith the axis of the hidden screw 7, a channel is drilled through the outer cortical layer of the femur 12 and contact is made with the hidden screw 11. Then, with the help of the hollow cutter 10, a wider channel is drilled so that when the device is removed from the bone marrow canal 2, the hidden screw 11 is in the lumen of the hollow cutter 10. The release of the bone marrow canal of the femur from the hidden screws allows you to go to the next stages of hip replacement.

Literature

1. Multiple and combined injuries: (practical hands for traumatologists) / V.A. Sokolov. - M.: GEOTAR-Media, 2006. - 510 p.: Ill .; 22 cm. - Bibliography: p. 485-510. - 2000 copies. - ISBN 5-9704-0161-7 (trans.).

2. The basics of internal osteosynthesis / V.M. Shapovalov, V.V. Khominets, S.V. Mikhailov. - M.: GEOTAR-Media, 2009 .-- 240 p .: ill. - (Library of a medical specialist). - ISBN 978-5-9704-1250-3. - from. 73.

3. Guide to internal osteosynthesis: Methodology, recommended. AO group (Switzerland) / M.E. Muller, M. Allgover, R. Schneider, X. Willinegger; [Trans. Korolev A.V.]. - 3rd ed. extension and completely re-worked. - M .: Ad Marginem, 1996 .-- 750 p .: ill. - Bibliography: p. 746. - Items decree: s. 747-750. - ISBN 5-88059-015-1: B. c. - from. 314.

Claims (1)

Sighting device for removing hidden screws from the femoral diaphysis, including a grip-head with a channel for introducing a drill followed by a milling cutter, characterized in that it contains a centralizer rod, a conductor branch parallel to it and a gusset connecting them, and the end of the centralizer rod equipped with a V-shaped groove for mounting on a screw hidden in the femoral canal, onto which the conductor branch channel is oriented, which is designed under the sleeve with a mandrel for a removable hollow drill or hollow cutters me.

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