RU2218113C2 - Device for taking cylindrical osteochondrous transplants - Google Patents

Abstract

FIELD: traumatology. SUBSTANCE: device includes cylinder with cutting edge and longitudinal through internal channel, depth limiter of transplant taking in form of circular projection on external surface of working cylinder and pusher accommodated inside cylinder. Pusher is made in form of piston and rod. Rod protrudes from opposite working part of cylinder on that end is less than its diameter in working part. Point of internal channel diameter variation is located above circular projection at distance from it larger than piston height, and made for limiting pusher stroke. EFFECT: provided convenience and rapidity in procedure execution, transplant integrity, control for depth of introduction into bone, reduced fraction of manual labor and application of surgeons physical efforts, due to device improved design. 3 dwg

Description

 The invention relates to medicine, namely to traumatology.

 A high level of injuries is noted all over the world (G. Yumashev, 1990). Intra-articular injuries of the knee joint are more and more common (Khabirova G.F., Shatrukov L.F., 1980). Damage to the articular cartilage due to trauma to the knee joint is observed in 24% -69% of patients (Vitiugov I.A., Stepanov B.C., 1979, Mironov S.P., Orletsky A.K., 1999).

 The presence of cartilage defects requires surgical treatment. Most often, bone-cartilaginous mosaic plastic is used to replace cartilage defects (Roland P.J., 1998).

 During surgery, there is a need to take bone-cartilage cylindrical grafts (Hangody L., 1997).

 The existing devices for the collection of bone-cartilage grafts do not always ensure the convenience and speed of the procedure, the safety of the graft, and control of the immersion depth of the device in the bone, require a significant proportion of manual labor and the surgeon's application of physical effort.

A device for taking cylindrical bone-cartilage grafts is known. The device is made in the form of a tube, which contains a cylindrical working part with a cutting edge at the lower end, to which the handle is connected. Inside the tube there is a longitudinal through channel, which has the same diameter throughout. The outer diameter of the handle is larger than the working part. The handle at the upper end has a transverse through channel, the diameter of which is equal to the diameter of the longitudinal. The introduction of the device into the bone is carried out with the help of hammer blows, the extraction with the help of circular rotations - for the additional handle inserted into the transverse channel. To extract the graft from the device, an additional cylindrical pusher is used, which is introduced from the cutting edge. (L. Hangody, G. Kish MosaicPlasty ^TM Osteochondral Grafting. Technique Guide. // Brochure Smith & Nephew Endoscopy Inc., publ. 07/1996).

The disadvantages of this device
- the device requires the use of physical efforts by the surgeon and a significant proportion of manual labor, which increases the time spent during the operation;
- difficulties in immersing the device in the bone and removing it from the bone;
- it is difficult to control the exact depth of immersion of the device in the bone.

The closest device to the claimed, selected as a prototype, is an apparatus for the restoration of cartilage defects. The apparatus for removing and replacing bone tissue includes a cylindrical cutting tool with a proximal cutting edge and a cutting tooth. The outer surface of the cutting element may include a single shoulder (for example, in place of a removable outer shell), which extends from the proximal cutting edge and captures the surface of the bone to determine the depth at which the cutting edge is deepened. An additional cylindrical element may be inside the cutting element. The proximal end of this additional element is precisely aligned with the proximal edge of the cutting element for receiving bone tissue (US Pat. US 6017348, CL A 61 B 17/00, "Apparatus and methods for restoration of articular cartilage defect", publ. Inventions of the world, Issue 7 , 2, 2001, p. 62)
The disadvantages of this device:
- the device requires the use of physical efforts by the surgeon and a significant proportion of manual labor, which increases the time spent during the operation;
- difficulties in immersing the device in the bone and removing it from the bone;
- the possibility of destruction by the cutting tooth of the graft, when removing it from the device.

 The objective of the present invention is to provide a device that provides convenience and speed of the procedure, the safety of the graft, control of the depth of immersion in the bone, reducing the proportion of manual labor and the application of physical effort by the surgeon.

 The problem is achieved in that the device for taking cylindrical bone grafts includes a cylinder with a cutting edge, a depth gauge for taking the graft. The fence depth limiter is made in the form of a circular protrusion on the outer surface of the working end of the cylinder, a plunger in the form of a piston and rod is located inside the cylinder, the rod extends from the opposite end of the cylinder, the diameter of the internal channel of the cylinder at the opposite end is less than the diameter of the working part. The place where the diameter of the inner channel changes is located above the circular protrusion on the outer surface of the cylinder and at a distance from it greater than the height of the piston of the pusher.

Device novelty
l. Ha on the outer surface of the cylinder there is a circular limiter for the depth of graft intake, made in the form of a circular protrusion on the outer surface of the working end of the cylinder.

 2. Inside the device there is a pusher consisting of a piston and a rod.

 3. The stroke of the pusher up is limited by changing the diameter of the inner channel.

 4. The place of diameter change is located above the circular protrusion on the outer surface of the cylinder and at a distance from it, greater than the height of the piston of the pusher.

The set of essential features of the claimed device allows you to:
- due to the working part receive transplants of a given size and shape;
- due to the fence depth limiter, it is easy to control the immersion depth of the device in the bone and receive transplants of the same length;
- the pusher provides the convenience of removing grafts from the device and their safety, which helps to reduce the duration of the operation;
- limiting the stroke of the pusher up prevents it from falling out from the side opposite the working part;
- due to the fact that the place of the diameter change is located above the circular protrusion on the outer surface of the cylinder and at a distance from it greater than the height of the plunger piston, the piston does not prevent the device from immersing in bone.

 The invention is illustrated by drawings, where figure 1 shows a drawing of a device; in FIG. 2 - vertical section; figure 3 is a photograph of the device Assembly.

 A device for taking cylindrical bone-cartilage grafts consists of a cylinder (1) with a working part, which has a cutting edge (2). On the outer surface of the working part of the cylinder there is a circular limiter for the depth of the graft intake (3), made in the form of a ring-shaped protrusion. Inside the device there is a longitudinally located through channel. The diameter of the channel in the upper part (5) is smaller than in the working (4). A pusher is located in the channel, which serves to extract the graft. The pusher consists of a piston (6) and a rod (7). The stroke of the pusher up is limited by changing the diameter of the inner channel. The location of the diameter change of the inner channel (8) is located above the limiter of the depth of the graft intake (3) and at a distance from it greater than the height of the plunger piston (6).

 The device works as follows: online access is performed, the place of grafts is exposed. The cylinder (1) is clamped into the cartridge of a medical electric drill. The working part of the cylinder (1) is placed in the place of graft perpendicular to the surface of the cartilage, touching it with a cutting edge (2). Turning on the electric drill causes the device to rotate. By longitudinal movement, in the direction of the cutting edge (2), the device is immersed in the bone. The immersion depth of the working part of the cylinder (1) is determined by the limiter of the depth of the graft intake (3). The determination of the graft depth is achieved by touching the limiter (3) of the cartilage surface. After that, the electric drill is turned off and on again, due to the change of modes, the graft is separated from the bone. By longitudinal movement in the opposite direction, the device is removed from the bone. At the same time, a cylindrical bone-cartilage graft remains in the channel (4). The device is removed from the cartridge electric drill. The graft is removed from the device by longitudinally moving the plunger rod (7), while the piston (6) pushes the graft out of the device.

 To obtain the required number of transplants, work cycles are repeated.

 The device is manufactured and used in the departments of traumatology and orthopedics since 2001. The device was used during operations in six patients. When using the device, it was found that the device provides convenience and speed of the procedure, ensures the safety of the graft when it is removed, allows you to control the exact depth of immersion in the bone, ensures the receipt of the grafts of the same size and shape, reduces the proportion of manual labor and does not require physical effort by the surgeon when introducing and removing the device from the bone. All of the above allowed to reduce the operation time by 25-30 minutes.

Claims (1)

A device for taking cylindrical bone-cartilage grafts, including a cylinder with a cutting edge and with a longitudinally located through channel, a depth gauge for taking the graft in the form of a circular protrusion on the outer surface of the working end of the cylinder and a pusher located inside the cylinder, characterized in that the pusher is made in the form a piston and a rod that extends from the opposite end of the cylinder, having a diameter of the inner channel less than the diameter in the working part, and the place of changing the diameter of the inner about the channel is located above the circular protrusion at a greater distance from it than the height of the piston, and is made to limit the stroke of the pusher.

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