DD293485A5 - INTRAMEDULLAERE OSTEOSYNTHESESPINDEL - Google Patents

Abstract

The invention relates to an intramedullary osteosynthesis spindle, which serves the optimal fracture supply by intramedullary stabilization of fractures or osteotomies of large tubular bones (upper arm, thigh, lower leg) in the context of the treatment of orthopedic-surgical conditions. According to the invention, the osteosynthesis spindle consists of a load-bearing traction spindle on which, in a different number and sequence, spreading elements of very different shapes with longitudinally laminated walls and, optionally, also slidable, spacers and a defect bridge are arranged. In this case, the last expansion element is designed as an anchoring element, in which engages the thread of the tensioning spindle. Except the load-bearing traction spindle, all components are preferably made of resorbable biovertraeglichen polymer materials. Before the osteosynthesis spindle is inserted into the drilled out medullary cavities of the tubular bone to be supplied, it is put together in a fracture-individual manner from the appropriately dimensioned expansion elements and variable spacers, possibly taking into account a defect bridge to be inserted, and the anchoring element is attached. After driving the osteosynthesis spindle in a conventional way with the standardized instruments, an axial pressure is exerted on the expansion elements by actuation of the load-bearing traction spindle or a separate tensioning element, thus achieving a displacement and rotation-proof locking in the medullary area. The traction spindle is designed as an intramedullary force carrier, thereby assuming the mechanically stabilizing function of the conventional scissor nail. {Osteosynthesis spindle, intramedullary; Kuentschernagel; medullary cavity; feed shaft; spreader; Distanzstuecke; Defektbruecke; Anchoring element; resorbable biocompatible polymer materials}

Description

For this 4 pages drawings

Field of application of the invention

The osteosynthesis spindle serves for the intramedullary stabilization of fractures or osteotomies of the large bones (upper arm, thigh, lower leg) in the context of the treatment of orthopedic-surgical conditions.

Characteristic of the known state of the art The KÜNTSCHER nailing in fractures of large bones (Fdmur, humerus, tibia) is an established method of

operative bone fracture treatment (BÖHLER, L. 1945). In this case, a metal tube cloverleaf-shaped profile in the medullary cavity of the broken tubular bone, from a proximal point, advanced. This force-absorbing implant acts like a "rigid bending torsion spring" (TEUBNER, E. 1985) .A fibrous callus cuff forms around the fracture gap, which solidifies by incorporation of mineral salts and thus leads to bone fracture healing.

A major disadvantage of Küntscher nailing is the lack of rotational stability and the tendency of the implant to

axial displacement as a result of insufficient radial tension in the medullary cavity (EITEL, F. 1981).

To improve the fracture supply and to extend the indication to complicated floor, multi-fragment and Debris fractures introduced the external locking nailing, in which, through from the outside into the bone

inserted, locking pin nail unc! Bones are brought into a solid, load-stable structure.

The sighting and meeting of the locking holes in the nail through the. Prove to be problematic and difficult Bones through. There is therefore no shortage of attempts to introduce an internally interlocked nail into clinical practice. Known operating principles are based on the fact that arranged inside a conventional nail Spreizklauen metal

are that can be extended with a threaded spindle.

Other known solutions provide a combination of external and internal locking. Another The design principle is based on the fact that flexible Lammellen be introduced into the bone cavity and braced. None of the proposed nails could enforce either because they are not extractable as a result of deformation

or growing around, or the mechanics of Spreizklauen resist the deforming loads of Eintreibes in the

Mark cave not. Known is a support element for long bone fractures (AT A 9640-75), which consists of several, in the axial Direction of successive and loosely intermeshing sleeves and consists of a sleeve from end sleeve to end sleeve

continuous flexible band is clamped. This support element is so flexible during the insertion. Thus, although the introduction into the arc-shaped outward bore in the bone is simplified but the lastaufnehmende

Support effect u.E. not guaranteed because a flexible tensioning bath for the expected deformation forces than not

is considered sufficient. All other disadvantages already described above can not be eliminated with this solution anyway.

Other devices require for their implantation primarily the surgical opening of the bone fracture. The However, nail nailing is used to protect the blood supply to the fractured fragments and to prevent

Infections as closed as possible, i. performed without opening the bone fracture area.

The so-called open nailing will be necessary for reduction obstruction and occasionally for debris fractures, but remains more the more complication-seeking exception method.

Another solution, which is obvious to the invention, DE-OS 3023999 (US priority 52822 v. 27.06.79) proposes a model in which elements spreading and tying in the medullary cavity are connected via a traction spindle and the fracture under antagonistic direction of action Put compression.

The analysis of this patented solution reveals that the introduction of the described device into the medullary cavity is possible only through the operative opening of the bone fracture, and that in the case of any type of fracture. All the disadvantages of open nailing and their complications already described must be taken into consideration. Also, the proposed osteosynthesis device excludes major corrections of the implant position and is in the indication only suitable for single fractures, which are supplied safely and better by conventional methods.

Object of the invention

The aim of the invention is to ensure an optimal fracture supply by intramedullary stabilization, even in complicated floor, Mehrfragment- and debris fractures of the large bones, with minimal patient burden.

Explanation of the essence of the invention The object of the invention is a conventional way with the standadisierton instruments in the inside of the bone

To create engageable, fracture-individually adjustable and collapsible, and in the medullary cavity displaceable and rotationally secure lockable osteosynthesis device.

According to the invention, the object is achieved in that on a load-bearing pull spindle, in different numbers

and sequence, slidable spreading as cylindrical or conoidal or ellipsoidal, rotationally symmetrical hollow body with längsgelammellierter wall and optionally, also slidably, spacers, and a defect bridge are arranged, wherein the last expansion element is designed as an anchoring element, in which engages the thread of the tensioning spindle. To the

For purposes of better deformability, the spreading elements are advantageously radially divided and the element halves inside

designed as a truncated cone.

The complementary to this modular principle proposed defect bridge of biocompatible Vitrokeramik- or Glass material is divided axially and advantageously consists of cylindrical, longitudinally ribbed half-glass. The spreading, the spacers, the defect bridge and the anchoring element are preferably made

resorbable biocompatible polymer materials.

The osteosynthesis spindle is inserted into the drilled medullary cavity of the long bone to be supplied prior to insertion

according to the circumstances of the bone defect from the defined dimensioned expansion elements and variables

Spacers, possibly taking into account a defect bridge to be introduced, put together and the

Attached anchoring element.

After usual driving into the medullary cavity is by actuation of the load-absorbing traction spindle or a separate Clamping element exerted an axial pressure on the expansion elements, which expand radially and under reduction

jam their original height in the marrow cavity.

The anchoring element is doing according to the anatomical conditions either by spreading in the

anchoring in a trumpet-shaped dilating distal medullary cavity or in the cancellous area of the metaphysis or, like the entirety of the spreading elements, also spreading radially through the exertion of the axial pressure and in the

Clamp the bone cavity. The traction spindle, designed as intramedullary force carrier, takes over the mechanical

stabilizing function of the conventional Kuntschernagels.

The defect bridge is introduced at the surgical opening of the bone fracture. It has a larger diameter than that Mark cavern, in order to achieve a support function longer-lasting bone defects. In addition to the traction spindle, all elements of the osteosynthesis spindle are preferably made of resorbable material

biocompatible polymers. They are degraded with increasing fracture structure and afford the function-oriented

Kallustransformation in the sense of a fractionated dynamization of the fracture feed. For the prophylaxis and therapy of infections, the impregnation of the polymers and the Vitrokeramiken or Glass materials with antimicrobials possible. exemplary The invention will be explained in more detail with reference to an embodiment and to two applications. Show 1 shows an embodiment of the osteosynthesis spindle, Fig. 2: the tension spindle 3a: a spreader in plan view, partially in section, 3b: a spreading element in longitudinal section, 4 shows an embodiment of the anchoring element, 5: a defect bridge (top view), 6: a Oberarmetagenfraktur and Osteosynthesespindel supplies, Fig. 7: a femoral defect fracture supplied with an osteosynthesis spindle using a defect bridge.

In Fig. 1, an osteosynthesis spindle is shown completely. The load-bearing traction spindle 1 has at one end the spindle head for driving into the medullary cavity of the bone, wherein the spindle head is provided with a hexagon socket to allow the clamping r. For the design of the spindle head and other constructive solutions are conceivable, especially if a twisting, z. B of a bent pulling spindle, is not possible.

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The thread arranged at the other end engages in the thread of the anchoring element. On the tension spindle 1 are between spindle head and anchoring element 5 slidable Sproizelemente 2, spacers 3 and

a defect bridge 4 is arranged.

The arrangement of the individual elements takes place, adapted in different numbers and order, fracture individual. The

Defective bridge 4 consisting of half-shells is always used after the osteosynthesis spindle has been driven in operationally

Opening of the bone fracture site introduced from the outside. The spreading elements 2 are designed as radially divided hollow body and have an ellipsoidal shape. Fig. 3 a shows Spreader 2 in partially cut to the dividing line top view. 3b shows a longitudinal section of the Spreizelomentes second If the complete osteosynthesis spindle is located in the medullary cavity, turning the load-bearing traction spindle 1

by means of an Allen wrench, the anchoring element 5 spread apart, the latter wedged in the medullary cavity.

At the same time, these radial expansion and jamming by the resulting axial pressure on the expansion elements

reducing their height of origin in the medullary cavity. The spacers 2 secure their position on the

Traction Spindle 1. The half-shells of the defect bridge 4 take over the support function in the case of longer bone defects,

the longitudinal ribbing of the defect bridge, shown in Fig. 5, allows you to have a simultaneous spongiosa aplasty.

As an application, Fig. 3 shows a humeral tractural fracture. Upper arm fractures are the intramedullary nailing previously difficult to access, as they easily to longitudinal and rotational misalignments

tend. Their secure supply by the osteosynthesis spindle according to the invention would thus be an essential

Indicator gain for the intramedullary nailing. The illustrated fracture is reduced, drilled out through the usual approach, and with a preoperative, fracture-individual

composed Osteosynthesespindel, consisting of the load-bearing tension spindle 1, 2 and spreading elements

Spacers 3, intramedullary splinted. After checking the position of the fragments and the osteosynthesis spindle, the tension takes place. At the distal end is this one Anchoring torque 5, in the form of a threaded spreader, deposited. As another application, a femoral defect fracture is shown in FIG. Such defects can be caused by accident, wounded casualties or tumor-related bone destruction

be caused. Your load-stable care is a problematic task in therapy.

The preparation for nailing also takes place here in the usual way and with the usual methodology. However, here is to

load-stable supply of the defect a defect bridge of Biovitrokeramik, which also allows a simultaneous Spongiosaplastik by the longitudinal ribs, necessary.

On the longitudinal ribs, the bone is supported. To insert the defect bridge 4 is longitudinally divided, thus consists of two half-shells. After operational exposure of the Defective distance, the two half shells are used open. The osteosynthesis spindle is prepared preoperatively so far

that the tension spindle lan its tip is provided with an anchoring element 5. Furthermore, spreading elements 2 and a spacer 3 are arranged on the drawing spindle 1 according to the fracture-specific requirements, a corresponding clearance being taken into account for the defect bridge. After driving the tension spindle and arrangement of two

Spreading elements 2 in the lower fragment area is the defect individual adjustment and insertion of the half shells of Defect bridge 4. The bracing is then carried out analogously as described in Application 1.

Claims (4)

1. Intramedullary osteosynthesis spindle with spreading elements, characterized in that on a load-carrying traction spindle (1), in different numbers and sequence, slidable spreading elements (2), as cylindrical or conoid or elHpsoide, rotationally symmetrical hollow body with längslamellierter wall, and optionally, also lubricious Spacers (3) and a defect bridge (4) are arranged, wherein the last expansion element is designed as anchoring element (5), in which engages the thread of the tension spindle (1). 2. Intramedullary Ostesosynthesespindel according to claim 1, characterized in that the spreading elements (2) are advantageously divided radially and the element halves are internally designed as a truncated cone. 3. Intramedullary osteosynthesis spindle according to claim 1, characterized in that the defect bridge (4) is divided axially and advantageously consists of cylindrical, longitudinally ribbed half-shells. 4. Intramedullary osteosynthesis spindle according to claim 1 to 3, characterized in that the spreading elements (2), the spacers (3), the defect bridge (4) and the anchoring element (5) preferably consist of resorbable biocompatible polymer materials.