WO2008048195A2

WO2008048195A2 - Post-reduction adjustable modular hip prosthesis

Info

Publication number: WO2008048195A2
Application number: PCT/TR2007/000067
Authority: WO
Inventors: Mustafa Altan Kabalak
Original assignee: Mustafa Altan Kabalak
Priority date: 2006-10-20
Filing date: 2007-07-13
Publication date: 2008-04-24
Also published as: WO2008048195A3

Abstract

The invention is the femoral component of partial, total and revision/trochanteric prostheses used in the surgical treatment of hip fracture and coxofemoral diseases. Consisting of a head (1), a neck (2) and a stem (3) part, it is the modular hip prosthesis on which neck length and accordingly off-set and anteversion angle adjustments can be made before or after the prosthesis has been reduced into the acetabulum.

Description

POST-REDUCTION ADJUSTABLE MODULAR HIP PROSTHESIS

Technical Area

The invention is about the femoral components developed for the surgical treatment of human hip fracture and coxofemoral diseases.

The invention is especially about the adjustable modular prostheses after the prosthesis' reduction to the acetabulum.

The Background of the Invention

Numerous surgical treatment prostheses are performed in the treatment of hip fractures and coxofemoral (acetabulum) diseases. These prostheses are the metallic formations that ensure the connection and function between the acetabulum in the pelvis and the main femur bone after the reduction of fractured or diseased bone in such cases as proximal femoral fracture and the surgical treatment of coxofemoral diseases. The said prosthesis consists of three main parts. In the acetabulum, it has a spherical head that allows movement. The component which has the control of the head and ensures the movement transmission to the leg is the neck. On the other end of the neck - which is anatomically appropriate, thin-long, and curved at a certain angle - there is the stem fixing the prosthesis to femur. The stem is located in the medulla.

Technically, there are prostheses with fixed neck-stem and modular neck-stem structures. Their head parts are modular and they are located in acetabulum after being fixed with press-fit system (reduction).

In the modals with fixed neck-stem part, the stem is located lengthways in the medulla in femur. As the anteversion angle is set through winding according to the femur, fixing a mistake that might be made shall create a great problem. If there is a problem with the anteversion angle in a cemented prosthesis, you'll need to take the prosthesis out in order to reset the angle. Osteotomy needs to be applied to take out the prosthesis, which shall weaken the bone's strength and create post-treatment problems. It is easier to take out the prosthesis if a cementless stem has been used. However, as the medulla has loosened in that case, a stem of a bigger size needs to be located, and this shall cause the femur's loss of strength.

The stem is long especially in revision total hip prostheses -combined hip prostheses replacing the acetabulum and the femoral head- and in trochanteric partial prostheses -replacing the femoral head in the fractures in trochanteric area- (trochanter; the upper part of the femur). As a result of this length, there are many problems in calculating the anteversion angle.

Neck length and offset adjustment are performed in two different ways. For the ones with a fixed neck-stem, the neck is long or short according to the size of the stem. For the ones with a mobile neck, the mobile neck part at an appropriate size is mounted in the stem.

The other way of neck length and offset adjustment is performed at the head part. The head is made for different lengths (small, medium, long, xl).

The neck lengths of the femoral components that are still used are adjusted before reduction on the acetabulum, no matter what kind of femoral components exist. In that case, it is usually not possible to adjust the patient's anatomic neck length.

If the neck is short or if the prosthesis' stem has been overpushed, reduction shall be easier. As a result, as the anatomic neck length has not been ensured, the risk of post-operative hip dislocation increases; and as the anatomic offset has not been adjusted, limping shall come out because the hip muscle group and especially the abductor muscle group shall not work in the individual's anatomic measures.

Reduction is performed hard if the neck length has been adjusted in accordance with the anatomic measures and femoral head cannot skip the edge of the acetabulum during reduction. In that case, if the reduction has been performed, though rarely, it shall cause the partial prosthesis' protrusion in the acetabulum and movement limitation in the hip. However, it depends on the bone structure, too.

Technically, numerous improvements to eliminate the said disadvantages have been made;

In the applications no US2002040244 with the title of "Modular femoral stem component for a hip joint Prosthesis", no US2003074079 with the title of "Differential porosity prosthetic Hip System" and application no US2002151984 with the title of "Prosthesis Having Wedge-shaped Body"; partial remedies have been found through ensuring the neck-stem connection with a bolt. In these applications, it has been stated that the hip prosthesis is configured with a modular connection between the neck, the stem and the body; and that a safe connection between the neck and the stem has been in ensured via modularity. The stem is located in the body carrying the neck and fixed with a bolt that is attached to the other side of the body. In other words, angle adjustment is made possible through connecting the modular neck to the cylindrical stem. These applications are the modular ones consisting of three parts (head, neck, stem) of different geometries and sizes; and ensuring the adjustability of these components according to each other. After fixing the prosthesis; a bolt, socketed system or a notch is used to connect the three components with their final forms and to prevent movement.

In the application no EP1493407 with the title of "Modular Hip Prosthesis", the technique has been improved a little more and it has been stated that the modular orthopedic hip prosthesis consists of three main components -a stem, a proximal body and a neck-, and that these components are demountable and adjustable. It is also stated that the neck can be adjusted through rotating around the stem, the head part is rotatable and can be adjusted as an axis, and the prosthesis is the one with an inner component that ensures the locking of these movable elements with the help of a bolt. In the application no EP0677281 with the title of "Femoral Prosthesis for Recovering Implantation which has Provided Negative Results", an upper body has been improved in order to prevent the negative results of prosthesis. The proximal body is in the form to be connected to and detached from the outer body with a conical socketed stem, a conical upper body narrowing downwards named conic end-piece which is sectionally elliptic has been realized.

In the application no US5702479 with the title of "Shaft Component for a Joint Endoprosthesis", an easy adjustment of the anteversion angle of the hip prosthesis with a bolt formed stem has been aimed. There is a base component which ensures that angle of the neck of the prosthesis according to the rotation axis stays in 70° and which ensures its rotation over the stem; and there is an adjustment component between the threads of the base component and that of the stem. The reduction process is completed with a bolt which connects the base component, the intermediate component and the stem after the adjustment.

In the applications mentioned, no kind of adjustment or intervention is made without luxating the acetabulum from the prosthesis in the revision operation during or after the surgical operation. The necklength, off-set or anteversion angle adjustment cannot be made without luxating the prosthesis from the acetabulum. The head's luxation from its hole after the prosthesis in Figure 4b is placed (reduction) is one of the other irrepressible problems.

Objects of the Invention

In view of the present position of technique, the purpose of the invention is, with the help of totally new improvements, to eliminate the present disadvantages of femoral components developed for the surgical treatment of hip fractures and coxofemoral diseases. Another purpose of the invention is to decrease the problems that appear during the operations and the postoperative complications related to the prostheses which are still being used.

In order to attain the said goals, some kinds of renewals have been realized in the modular hip prosthesis consisting of a head (1 ), a neck (2) and a stem (3) that is used for the surgical treatment of hip fractures and coxofemoral diseases.

In one of the preferred applications of the invention, in order to ensure the neck length and off-set adjustment when the said head is placed on the neck, at least one inner thread has been used. This said inner thread makes the adjustment of the said head through rotating possible and is located in the inner hull of a cylindrical hole of which open side is through the inner head part in the form of a thread canal.

In one of the preferred applications of the invention, in order to ensure the neck length and off-set adjustment when the said head is rotated on the neck, at least one neck part, the two ends of which have been connected to the head and the stem has been realized. This said neck is in the form of a cylindrical bar with threads all over the surface. In this way, during a surgical intervention, neck length and anteversion angles shall be adjusted without any operation on the stem after the head has beenlocated on the acetabulum (reduction).

In one of the preferred applications of the invention, in order to make the said hip movements stay within the anatomical dimensions and to decrease the risk of hip dislocation, at least one proximal part which has been formed on the neck side of the head has been realized. This cylindrical part is in the form of creating degrees in the anatomic dimensions between the head and the neck, and it ensures leaning over the edge of acetabulum. In this way, the head shall not be dislocated from the edge of acetabulum and luxation shall not happen in case of the patient's overmovement. This way, overangled movement of the head (1) and the neck (2) has been limited. In one of the preferred applications of the invention, in order to ensure a connection to the neck to support the locknut after the adjustment of the said head part, several bolt notches that are configured on the said head part and that ensure the head's fixation on the neck and that have threads on have been formed.

In one of the preferred applications of the invention, in order to ensure a connection to support the locknut on the neck after the head has been adjusted, several bolts connected to the said bolt holes have been formed to fix the head on the neck. In one of the preferred applications of the invention, the said fixing bolt cap is optionally without a head in the form to be embedded in the bolt hole.

In one of the preferred applications of the invention, in order to ensure the fixation to the neck after placing the said head part on the neck through rotating, at least one locknut which moves on the said neck and fixes the head on the neck has been formed.

In one of the preferred applications of the invention, in order to ensure the fixation of the neck through adjusting the anteversion angle according to the stem, at least one angled tip which is formed on the stem-side of the said neck, and which ensures movement within the limits of the anatomical angle has been used.

In one of the preferred applications of the invention, in order to ensure the fixation of the said neck according to the stem through adjusting the anteversion angle, at least one neck fixing socket which is formed on the said stem on the neck side, which ensures movement within the limits of the anatomical angle and which ensures the standard head-neck-stem angle of 135° has been realized. In this way, unlike the recently used prostheses, this femoral component is placed on the femur, it is easily located on its place (acetabulum) on the pelvis (reduction) and the anteversion angle of the patient can easily be adjusted according to his/her anatomical dimension.

In one of the preferred applications of the invention, in order to ensure the anteversion angle of the said neck, the angle between the said neck and the angled tip is characterized with X. In one of the preferred applications of the invention, in order to ensure that the anatomical inclination angle of 135° is fixed while the anteversion angle is adjusted through applying the X angle between the said neck and the angled tip (in order to balance the axial slip of the X angle), the direction of the neck fixing socket is changed to the Q degrees which is the angle between the neck fixing socket and neck axis.

In one of the preferred applications of the invention, in order to ensure the connection of the said angled tip and the neck fixing socket that are clamped together, the connection surface of the said angled tip has a longitudinal intricate notch form. In one of the preferred applications of the invention, in order to ensure the connection of the said angled tip and the neck fixing socket that are clamped together, the connection surface of the said neck fixing socket has an intricate notch form.

In one of the preferred applications of the invention, in order to ensure prosthesis measure appropriate for the bone size of atrophic and small bones in the medulla, a thread has been opened and a double component prosthesis with a fixed neck-stem and a mobile head part has been formed. In another preferred application of the invention, the said thread has been opened, the neck (2) and stem (3) anteversion angle is fixed and these components are connected in a way that they can not open.

In one of the preferred applications of the invention, in order to ensure that the said prosthesis is revision total or trochanteric partial prosthesis, at least one round pinned stem which is connected to the femur, which has lengthwise chamfers to prevent rotation in the femoral medulla has been realized. On the upper part of this pinned stem, the neck can be adjusted and connected through rotating.

In one of the preferred applications of the invention, in order to ensure that the anteversion angle of the head can be adjusted after the said pinned stem has been placed in the medulla and in order to ensure its connection to the pinned stem, at least one rotatable upper body part which has been formed below the said neck, and which ensures connection to the said pinned stem through adjustment. So that this rotatablθ upper body said can accord with the defect in the femur; the neck is placed over the rotatable upper body. Thus, the said prosthesis can become a revision total hip prosthesis or a partial prosthesis for trochanteric fractures when necessary. In this way, the anteversion angle of the head part can be adjusted after the said pinned stem has been placed in the medulla.

In one of the preferred applications of the invention, in order to ensure that the anteversion angle of the head part can be adjusted after the said pinned stem has been placed in the medulla and to ensure that the head can be connected to the pinned stem; at least one rotatable lower body which is formed below the neck and which can be connected to the said pinned stem through adjustment has been realized. So that this rotatable lower body can accord with the defect in the femur, it has been placed below the rotatable lower body. Thus, the said prosthesis can become a revision total hip prosthesis or a partial prosthesis for trochanteric fractures when necessary. In this way, the anteversion angle of the head part can be adjusted after the said pinned stem has been placed in the medulla.

In one of the preferred applications of the invention, in order to ensure the connection of the said rotatable upper body or of the rotatable lower body to the said pinned stem, to adjust and determine the anteversion angle, several locknotches that are formed on the contacting surface of the said rotatable upper or lower part to the pinned stem have been made on a circular axis. These locknotches also make the angle adjustment possible.

In one of the preferred applications of the invention, in order to ensure the connection of the said rotatable upper or lower part to the said pinned stem, to adjust and determine the anteversion angle; multiple body locknotches that are formed on the contact surface of the said upper body to the pinned stem, that ensure the angle adjustment and that are formed compatible with the locknotches have been made. In a preferred application of the invention, in order to ensure the connection of the said rotatable upper or lower part to the said pinned stem, to adjust and determine the anteversion angle; multiple body locknotches that are formed on the contact surface of the said lower body to the pinned stem, that ensure the angle adjustment and that are formed compatible with the locknotches have been made.

In a preferred application of the invention, in order to adjust the angle of the said rotatable upper or lower part to and to connect it to the pinned stem, at least one stem pin has been placed. This stem pin said has been formed on the rotatable upper body or on the rotatable lower body side of the said pinned stem.

In a preferred application of the invention, in order to ensure the connection of the said upper or the lower body to the stem pin after the anteversion angle of the said upper or lower part has been adjusted, at least one nut fixing tip with threads on which is formed on the upper part of the said stem pin has been formed.

In a preferred application of the invention, in order to ensure the connection of the said upper or the lower body to stem pin after the anteversion angle of the said upper or lower part has been adjusted, at least one fixing nut which is connected to the said nut fixing tip and which ensures fixation has been formed.

In a preferred application of the invention, in order to ensure the connection of the said upper or the lower body to stem pin after the anteversion angle of the said upper or lower part has been adjusted, at least one left bolt fixing hole which has been formed as a hole on the upper part of the stem pin and which has threaded notches on has been realized.

In a preferred application of the invention, in order to ensure the connection of the said upper or the lower body to stem pin after the anteversion angle of the said upper or lower part has been adjusted, at least one left bolt which is connected to the left bolt fixing socket and which prevents the bolt from loosening has been formed.

In this way, in case of a problem about the anteversion angle or the neck length after the placement of the prosthesis, femur shall not be operated on as the stem isn't taken out of the femur in order to be fixed. For this reason, the durability and the maintainability of the femur shall not deteriorate. Thence, the prosthesis shall create great advantages in preventing complications and shortening the duration of the operation.

In this way, according to the model both pre-reduction and post-reduction adjustment of the anteversion angle has been made possible. As the neck length and off-set adjustments are made after the reduction to the acetabulum, such problems encountered previously have been eliminated. However, for the femurs with narrow or small medullas (fixed neck-stem); fixed anteversion angled prostheses are used (figure-2). As the neck length adjustment is made after the reduction in all models, placement of the invented prosthesis on the patient is both easy and appropriate for the anatomical dimensions of the patient.

Brief Description of the Drawings

Figure-1a is the sectional lateral demounted view of the modular prosthesis consisting of 3 main parts in a figurative application of the invention.

Figure-1 b is the sectional lateral demounted view without the head of the threaded neck-stem part of the prosthesis consisting of 3 main parts in a figurative application of the invention.

Figure-1 c is the sectional view of the prosthesis turned left while the anteversion angle is being adjusted in its mounted form of the prosthesis consisting of 3 main parts in a figurative application of the invention.

Figure-Id is the sectional view of the anteversion angle of 0° while the anteversion angle is being adjusted in its mounted form of the prosthesis consisting of 3 main parts in a figurative application of the invention. Figure-1e is the sectional view of the prosthesis turned right while the anteversion angle is being adjusted in its mounted form of the prosthesis consisting of 3 main parts in a figurative application of the invention.

Figure-1f is the perspective of the cogs from below when the neck is mounted on the stem of the prosthesis consisting of 3 main parts in a figurative application of the invention.

Figure-2 is the lateral demounted view of the hip prosthesis' model with a fixed neck- stem and a mobile head part in a mounted way in a figurative application of the invention.

Figure-3a is the sectional lateral demounted view of the revision total hip prosthesis and/or the trochanteric partial prosthesis in a figurative application of the invention.

Figure-3b is the lateral sectional view of the stem part of the revision/trochantehc hip prosthesis in a figurative application of the invention.

Figure-3c is the lateral sectional view of the rotatable upper bodied model of the neck part of the revision/trochanteric hip prosthesis in a figurative application of the invention.

Figure-3d is the lateral sectional view of the rotatable lower bodied model of the neck part of the revision/trochanteric hip prosthesis in a figurative application of the invention.

Figure-3e is the lateral sectional view of the locking threads which adjust the anteversion angle of at the neck part and the stem part of the revision/trochanteric hip prosthesis in a figurative application of the invention.

Figure-4a is the front view of the application of the hip prosthesis' head part that prevents luxation in a figurative application of the invention. Figure-4b is the view of the known application of the technique of the hip prosthesis' head part that causes luxation in a figurative application of the invention.

Figure-4c is the sectional lateral view of the head part of the partial prosthesis consisting of 3 main parts in a figurative application of the invention.

Figure-4d is the sectional lateral view of the head part of the total prosthesis consisting of 3 main parts in a figurative application of the invention.

Figure-4e is the view of the neck side of the head part of the prosthesis consisting of 3 main parts in a figurative application of the invention.

Figure-4f is the view of the locknut which ensures fixing the head part on an appropriate location on the neck of the prosthesis consisting of 3 main parts in a figurative application of the invention.

Figure-4g is the sectional lateral view of the prosthesis consisting of 3 main parts and which has been reduced to the acetabulum but the neck length and off-set of which have not been adjusted in a figurative application of the invention.

Figure-4h is the sectional lateral view of the prosthesis consisting of 3 main parts after the prosthesis has been reduced to the acetabulum and the neck length and the off-set have been adjusted in a figurative application of the invention.

Reference Numbers

1 Head 7 Inclination angle

1.1 Head Extension 8 Pinned stem

1.2 Inner thread 8.1 Fixing nut

1.3 Bolt hole 8.2 Left bolt

1.4 Fixing hole 8.3 Nut fixing tip

2 Neck 8.4 Left bolt fixing hole 2.1 Angled tip 8.5 Locknotch

2.2 Rotatable upper body 8.6 Stem pin

2.3 Rotatable lower body 9 Acetabulum

2.4 Body Iocknotches 10 Movement axis of the head

3 Stem 11 Limited head movement axis

3.1 Neck fixing hole 12 Abduction angle

3.2 Collar 12.1 Femur-Central lines

4 Neck axis 12.2 Lower part of the acetabulum

5 Hole axis 12.3 Upper part of the acetabulum

6 Locknut 13 Limited abduction angle

Detailed Description of the Invention

The application of the invention presented in the figures is the adjustable modular hip prosthesis in order that the problems encountered during operations and postoperative complications can be decreased.

The hip prosthesis has been formed on the basis of three main principles;

1- Adjusting the neck length and the off-set in accordance with the anatomical dimensions after the prosthesis has been located on its place in the pelvis (acetabulum),

2- Angling the prosthesis forward according to the stem of the femur (anteversion angle) before or after the reduction is performed, 3- The diameter of the head extension (1.1 ) of the prosthesis is proportional with the anatomical neck diameter and the anatomical head diameter. As it keeps the hip movements within the limits of anatomical limits, it reduces postoperative luxation complications.

The neck (2) with threads on and the head (1 ) part;

The neck (2) length is adjusted before the reduction is applied in the femoral components that are used at present. As this is usually not made in anatomical dimensions, the cases of postoperative complications such as postoperative luxation and limping are widely seen. In the prosthesis invented, the ideal neck length adjustment can be made after each component has been placed and reduced in their place in the pelvis (acetabulum). This way, femur acetabulum stabilization can be adjusted in accordance with the anatomical dimensions. As the neck (2) length and accordingly off-set adjustment is made in accordance with the anatomical dimensions; hip muscle balance, especially the abductor muscle group, shall work within the anatomical limits and a remedy for the patient's postoperative complications has been found. In industrial technologies also, all the components of a system are placed and the results are obtained after the final adjustments. However, this opportunity does not exist in the other prostheses used at present.

A thread has been opened on the whole surface of the neck seen in Figure 1a and 1b. With the neck (2) on which a thread has been opened it is possible to adjust the hip prosthesis according to anatomical dimensions, and during the surgical operation, it is possible to change the position of the head (1) -if necessary- without moving the stem (3). It is also possible to adjust the position of the head part (1 ) after it has been placed on the acetabulum (reduction). One end of this neck (2) is connected to the head (1 ) and the other end is connected to the stem (3) in a way to move through rotating. The neck is in the form of a cylindrical bar with threads all over the surface.

The neck (2) consists of two parts: The threaded neck (2) part on which the head (1 ) is placed and the angled tip part (2.1 ) which is placed in the stem (3). It has the diameter to accord with all kinds of heads. The head part (1) seen in Figures 4c and 4d is spherical and a cylindrical hole has been opened on it. The hull of the hole is inner threaded (1.2). The diameter of the cylindrical hole is the same measure with the inner thread (1.2) in the hull. For this reason, the head (1) is placed on the neck (2) and can be totally approximated to the stem (3) through rotating clockwise, and it can be abducted from the stem (3) through rotating anticlockwise.

In partial and total prostheses, the head extension (1.1 ) on the stem (3) side of the head (1 ) is proportional with neck diameter/head diameter in anatomical dimensions. Within the head (1 ) and head extension (1.1), in the cylindrical hole and its hull; an inner thread which is compatible with the neck diameter and thread has been opened. The head extension (1.1) is in the form to be tightened with a wrench (Figure 4e).

In Figure 4c, there are heads (1 ) of different diameters from 38 to 60 millimeters for partial prosthesis which replace the femoral head. In the front part (the stem side) of the head (1 ), a extension which is proportionally measured to the neck diameter and the head diameter in anatomical dimensions has been placed. This said part is the head extension (1.1 ). This extension seen in Figure 4a exceeds the geometrical spherical line of the head (1) so that the head extension (1.1 ) can reduce the extreme movement limit through leaning over the upper end of the acetabulum (12.3) in case of an extreme movement of the hip. This situation prevents the luxation of the femoral head as the lower end of the acetabulum (12.2) and the head (1) apex get locked. Inside the head (1 ) and the head extension (1.1 ), there's a cylindrical hole to accord with the neck (2) diameter and there is inner threads (1.2) in the hull to accord with the thread on the neck. For this reason, all head kinds shown in Figure 4c and Figure 4d are compatible with the prosthesis types seen in Figures 1a, 2 and 3a. The head (1 ) can be approximated to or abducted from the stem (3) through rotating the head (1 ) over the neck (2). In this way, the neck length (2) of the prosthesis can be adjusted.

In Figure 4d, a head (1) with diameters of 32-28-26 millimeters have been used for the total hip prostheses (operations in which the femoral head and the acetabulum are changed together). In the front part (the stem side) of the head (1 ), a extension of which thickness is proportionally measured to the neck diameter and the head diameter in anatomical dimensions has been placed. The head extension (1.1 ) leans over the upper end of the acetabulum (12.3) and reduces the movement limit; so it prevents luxation of the femoral head as the head (1 ) apex cannot exceed the lower end of the acetabulum (12.2) (Figure 4a) and the head (1 ) apex get locked. Inside the heads (1 ), inner thread (1.2) canals with the same diameters are opened. For this reason, all head kinds shown in Figure 4c and Figure 4d can be applied to the prosthesis types seen in Figures 1a, 2 and 3a. The head (1) is placed on the neck (2) and it can be approximated to or abducted from the stem (3) through rotating (1 ) over the neck (2). In this way, the neck length (2) of the prosthesis can be adjusted.

The front view of the head (1) is presented in Figure 4e. The circular head extension (1.1 ) passes to the neck (2) of the heads (1) and it presents the anatomical neck (2) thickness. The neck side of this part has been shaped in the form to be adjusted by the nut wrench. On the head extension (1.1 ) seen in Figures 1a, 2, 3a and 4e; there are bolt holes (1.3) on the head extension (1.1 ) on which three fixing bolts (1.3) can be optionally placed. During the operation, the fixing bolt (1.4) is placed in a randomly chosen bolt hole (1.3). The cap of the fixing bolt (1.4) is embedded in the bolt hole (1.3), and there is preferably no cap.

The locknut (6) is used to fix the head (1 ) on an appropriate place on the neck (Figures 1a, 2, 3a and 4f). The locknut (6) placed on the neck (2) ensures the locking after the neck (2) length is adjusted through rotating the head (1 ) over the neck (2). The locknut (6) is approximated to the head through rotating. The head (1) is fixed on the neck (2) through rotating on the reverse directions with nut wrenches placed on the head extension (1.1 ) and the locknut (6) each.

In Figures 4g and 4h, the views of neck length and off-set both before and after the adjustment have been presented. First, the locknut (6) is placed on the neck as in Figure 4g then the head (1) is placed on the neck as in Figures 4c and 4d; and it is reduced to the acetabulum (9). In this view, the length of the neck (2) has not been adjusted. In Figure 4h, the neck (2) length has been adjusted and the head (1) has been fixed. The head (1 ) is approximated to or abducted from the neck (2) through rotating to left or right. When the neck (2) length has been adjusted, the locknut is rotated and approximated to the head. A nut wrench is placed on each the head extension (1.1 ) and the locknut (6), the wrenches are tightened through strongly turning to the reverse directions; this way the head (1 ) is fixed on where it has been adjusted on the neck (2) and it cannot move. The fixing bolt (1.4) is placed on the chosen fixing hole (1.3) during the operation and the fixing process is completed. As a result of the fixation of the head (1) with a locknut (Figure 4h), there is no opportunity for the head (1) to loosen. This method is one of the reliable ones which is still frequently used in technology; in dynamic, heavy load and vital systems. In spite of this fact, the system has been consolidated with a fixing bolt (1.4) added.

The application of 1^st Type Adjustable Modular Prosthesis (Figure 1a), The head (1 ), neck (2) and stem (3) are the three separate modular femoral components. It can be used as both partial and total prosthesis. The femoral bone's forward angling adjustment according to its stem (anteversion angle) can be performed after or before the reduction to the acetabulum through locating a head (1 ) on the modular neck (2).

The part on which the head of the prosthesis is placed as in Figure 1 a is the neck (2). It has standard and different length models. The diameter of the neck and the thread are compatible with the cylindrical hole and the inner thread (1.2) on the heads.

The part connecting the neck (2) to the stem (3) seen in Figure 1b is the angled tip (2.1 ). There are longitudinal recesses or indents on it. The stem (3) is the part which ensures the connection of the prosthesis to the femur. The mounting canal of the angled tip (2.1 ) on the stem (3) to the stem is the neck fixing hole (3.1 ). The longitudinal recesses and indents on the angled tip (2.1 ) have been made on the hull of this canal in the same size. Once the necessary anteversion angle has been obtained through partially placing the neck (2) with its angled tip (2.1 ) on the fixing hole (3.1) and rotating; the recesses and indents get telescoped through driving the neck (2) into the fixing hole, and the anteversion angle is fixed. When the appropriate anteversion angle has not been adjusted, the neck (2) is detached from the stem (3) with its apparatus again and the angle is readjusted. There are notches with longitudinal recesses and indents on the angled tip (2.1 ) as seen in Figure 1a. The angled tip (2.1 ) is placed on the neck fixing hole (3.1) on the stem (3), and it makes the adjustment and fixation of the neck (2) according to the stem (3) possible. The hull of the neck fixing holes (3.1 ) is also compatible with the angled tip (2.1 ), it has recessed and indented notches. The X angle exists between the threaded neck (2) and the angled tip (2.1 ) with which the neck (2) is connected to the stem (3) as seen in Figure 1 b. This angle ensures that the femur is angled forward according to its stem (anteversion angle) when the neck is rotated to the right or left. The X angle ensures the abduction or approximation of the head (1)-neck (2) axis from/to the central line with the angled tip (2.1) rotating in the neck fixing hole (3.1 ) when the neck (2) is rotated; as a result, it ensures the adjustment of the anteversion angle.

The Q angle exists between the neck axis (4) and the hole axis (5). In other words, Q angle is the one between the hole axis that passes through the central axle of the neck fixing hole (3.1 ) in the stem (3) and the neck axis in the head-neck axle. When the anteversion angle changes, the Q angle ensures that the inclination angle (7) stays stable.

With the adjustability of the neck's (2) approximation to and abduction from the stem (3) - which is ensured by the X angle; and the standard angle of 135° between the neck (2) and the stem (3) should also be stable. For this reason, as much as the drift created by the X angle, there is a Q angle between the neck (2) axis and the angled tip (2.1 ) axis in the reverse direction. This way, the standard inclination angle of 135° between the standard neck (2) and the stem (3) has been obtained, through adjusting an alternate angle with the Q angle as much as the drift of the X angle. For this reason, the angle between the head (1) - neck (2) central axis and the stem (3) central axis (angle of neck inclination, inclination angle) shall not change when the anteversion angle has been adjusted through rotating the neck (2). The inclination angle (7), namely the angle of neck inclination, stays stable at 135° (Figure 1a).

As seen in Figures 1a and 1 b, a bulge called collar has been placed on the neck (2) side of the stem (3). This collar ensures leaning over the prosthesis' femoral neck and gives the prosthesis the strength needed. The anteversion angles of the prosthesis seen in Figures 1a and 1b which are obtained when the neck (2) has been mounted on the stem (3) through rotating are shown in Figures 1c, 1d and 1e.

There are longitudinal recesses and indents on the neck's (2) angled tip (2.1 ) that fits in the stem (3). There are also recesses and indents of the same size on the neck fixing hole (3.1 ) of the stem (3). This way, the anteversion angle obtained when the angled tip (2.1) is driven into the neck fixing hole (3.1) is fixed. In Figure 1f, there is the enlarged view of the section that shows the accordance of the longitudinal recesses and indents when the angled tip (2.1) and the neck fixing hole are mounted on each other.

In an example application;

The stem (3) is placed on the femur. According to the stem's (3) placement on the femur, anteversion angle is applied on the neck (2) and the neck (2) is placed on the stem (3). Then the locknut (6) is placed on the neck (2) and it is approximated to the stem (3) through rotating clockwise. The appropriate one of the heads (1 ) of different sizes represented in Figures 4c and 4d is placed on the neck (2) through rotating clockwise. Then, it is approximated to the stem (3) through rotating (figure 4g). Reduction is applied to the acetabulum (9) (Figures 4g and 4h). The head (1 ) is abducted from the stem (3) through being rotated over the neck (2) anticlockwise. The neck length is adjusted until the anatomical stabilization to the femur's hole in the pelvis (acetabulum) is obtained and the forward angling of the femur according to its stem (anteversion angle) is checked. If it's not proper, the head (1 ) is loosened through rotating and the anteversion angle is readjusted. It is checked as in the first processes. Once the appropriate anteversion angle and neck (2) length have been adjusted; the iocknut (6) is rotated anticlockwise and is approximated to the head (1). A nut wrench is placed on both the head extension (1.1 ) and the locknut (6); the wrenches are rotated on reverse directions and tightened; then the fixing bolt (1.4) is placed and the operation is completed (Figure 4h). In Figures 1c, 1d and 1e; the prosthesis' views while the neck (2) is being rotated on the stem (3) are shown. As the neck is mobile, the upper part of the stem (3) is thicker. According to the research made, such prostheses can be used for bones having a femoral head with a longer diameter than 42 millimeters. When the femur has a smaller head or a smaller femoral medulla (atrophic) exists; prosthesis with a stable neck is suggested.

The application of 2^nd Type Adjustable Modular Prosthesis (Figure 2); It is used as partial and total hip prosthesis. In the prosthesis view seen in Figure 2; a modular type with two components has been applied: The head (1) is modular and the neck (2)-stem (3) are combined. The anteversion angle is adjusted during the placement of the prosthesis' stem (3). As the stem (3) is in different sizes, it can be used on all sizes of femur. The neck (2) has the diameter to accord with all heads (1 ) and it is threaded.

In an example application; First, the stem (3) is placed on the femur and the anteversion angle is adjusted, the locknut (6) is placed and it is approximated to the stem (3) through rotating. Then, the appropriate head is located on the neck (2) through rotating clockwise. Then, it is approximated to the stem (3) through rotating (Figure 4g). Reduction is applied to the acetabulum. The head (1) is abducted from the stem (3) through rotating anticlockwise. The neck length is adjusted until the anatomical stabilization to the acetabulum has been applied. The stabilization is checked through moving the hip. Then, the locknut (6) is rotated anticlockwise and it is approximated to the head (1 ). A nut wrench is placed on each the head (1 ) and the locknut (6), and they are tightened through strongly turning to the reverse directions. Then, the fixing bolt (1.4) is placed and it is tightened, too (1.4) Figure 4h). No kind of change shall occur in the neck length. If any problem appears later on, the same process is performed through loosening.

The application of 3^rd Type Adjustable Modular Prosthesis; The modular prosthesis seen in Figure 3a is the partial hip prosthesis for trochanteric fractures and the revision total hip prosthesis; it is a modular type with three components: head (1) - neck (2) - stem (3). Total prosthesis is the combined prosthesis which replaces the acetabulum and the femoral head. Partial prosthesis is the one which replaces the femoral head. Trochanter: the upper part of the femur situated at the junction of the neck.

There are two models for connecting the neck (2) to the pinned stem. If the neck has been located near the upper end of the body, it is in the form of a rotatable upper body (2.2); if it has been located near the lower end of the body, it is in the form of a rotatable lower body (2.3). The pinned stem (8) part of the revision total hip prosthesis and the trochanteric partial prosthesis is presented in Figure 3b. The pinned stem (8) is the stem part of the revision hip prosthesis. It has a round shape. Longitudinal recesses exist on the surface of the pinned stem (8) so that it won't rotate in the femur. It has numerous models with the diameter of 14 to 20 mm, and with the length of 180 to 300 mm.

According to the terms of service, the revision hip prosthesis consists of the montage of the pinned stem (8) to either the rotatable upper body (2.2) or the rotatable lower body. On the upper end of the pinned stem (8), a thread has been opened for the fixing nut (8.1 ) and a channel has been opened on its top for the left bolt (8.2). The fixing nut (8.1) moves on the nut fixing tip (8.3) shown in the Figures 3a and 3b. The left bolt (8.2) is connected to the left bolt fixing hole shown in Figures 3a and 3b. The fixing nut (8.1 ) stabilizes the pinned stem (8) with either the rotatable upper body (2.2) or the rotatable lower body (2.3) according to the terms of service of the revision hip prosthesis. Once the fixing nut (8.1) has been placed ant tightened, the left bolt (8.2) is placed and tightened. As the fixing nut (8.1) shall not loosen in such case, the rotatable upper body (2.2) or the rotatable lower body (2.3) shall not loosen, either.

In Figures 3c and 3d, the neck (2) types of the revision hip prosthesis with the shape of the rotatable upper body (2.2) or the rotatable lower body (2.3) have been presented. The locknotches (8.5) on the upper part of the pinned stem (8) have the same size of notches with the body locknotch (2.4) below the neck (2) types. The anteversion angle adjustment and the body locknotches (2.4) of the bodies in the rotatable upper body (2.2) and the rotatable lower body (2.3) used in the revision hip prosthesis are shown with lateral view. The locknotches (8.5) are connected with the body locknotches placed in accordance with the terms of service.

Either the rotatable upper body (2.2) or the rotatable lower body (2.3) is mounted on the pinned stem (8) according to the femoral defect. The neck (2) parts of both models have several lengths to meet the needs. The stem part of the pinned stem (8) components is in the form to accord with the femoral medulla and to prevent rotation.

However, in systems with a stable neck (2) - stem (3), some problems are encountered during the placement of the prosthesis in the medulla through applying the necessary anteversion angle of the long stemmed (3) prostheses. Because the slightest rotation of the long stem (3) during its placement on the femur causes great drifts in the anteversion angle. As the anteversion angle adjustment shall be made after the stem (3) is placed on the medulla in the invented prosthesis, such problems shall not be encountered.

In an example application; The pinned stem is placed in the medulla (in the femur). Then, the rotatable body (2.2 or 2.3) of the appropriate neck (2) is located in the stem pin (8.6) of the pinned stem (8) after the adjustment of the anteversion angle. The fixing nut (8.1) is slightly placed through tightening. The locknut (6) and the necessary head (1) is placed on the threaded neck (2) through rotating and it is approximated to the pinned stem (8), reduction is applied to the acetabulum. The head is abducted from the pinned stem (8) through rotating and the neck length is adjusted. The anteversion angle and stabilization are checked. If the anteversion angle is not appropriate, the head (1) is approximated to the pinned stem (8) through rotating and the neck (2) length is shortened. The fixing nut (8.1 ) is loosened and the anteversion angle is adjusted through rotating the rotatable body (Figures 2.2, 2.3) without causing the prosthesis' luxation. The head (1 ) is rotated again and is abducted from the pinned stem (8); the neck length and the off-set adjustment are performed. If there is no problem, the locknut (6) is rotated and approximated to the head (1 ). A nut wrench is placed on the head extension (1.1) and the locknut each and tightened; so the head is stabilized. Then, the fixing bolt (1.4) is placed on the bolt hole (1.3) and it is tightened. The fixing nut (8.1 ) is tightened. Finally, the left bolt (8.2) is placed on the left bolt fixing hole (8.4) and the operation is completed.

In total or partial prosthesis cases applied to the prosthesis in both Figure 1 a and Figure 3a; if an acetabular complication has occurred such as the protrusion of the prosthesis in the acetabulum, loosening, etc; if revision prosthesis application is necessary; if the stem-femur connection is stable and if there is no problem; the stem is not taken out of the femur. The head (1 ) in Figures 3c and 3d is loosened; the head (1 ) and the necks (2) used are properly detached from the stem. In this case, the space necessary for the operation on acetabulum has been opened easily. After the processes applied to the acetabulum are completed, the neck (2) used is placed in accordance with its type, the head (1 ) is placed, anteversion angle and neck length adjustment are made and the technical processes are completed. As the stem is not taken out of the femur, the durability and the maintainability of the femur shall not deteriorate. For this reason, as the stabilization lasts; there are vital advantages such as early postoperative movement, the serious decrease in complications and the shortening operation duration.

Preventing Luxation;

As the metal durability increases, the neck diameter is shortened in order to increase the range of hip movement. In press-fit systems, the diameter is measured 16/14, 14/12 and researches are made to have an even shorter diameter. As the neck diameter decreases, the movement limits of the femoral head in the acetabulum increases; the hip movements exceed the anatomical movement limits and spoil the acetabulum-femur stabilization; and it is not compatible with the hip anatomy. This situation is one of the postoperative luxation reasons.

In the skeleton examination, femur is the thinnest part and it is where the spherical shape of the head geometrically ends. The ratio of the vertical diameter of the femoral neck to the femoral head diameter is calculated between 72% and 78 %; and that of the neck's front-back diameter is calculated between 62% and 72%. In classic books, the anatomic ratio is stated to be 3/4*.

Press-fit 12/14 system partial prosthesis neck diameter/head diameter ratio is between 20% and 32%. This ratio is 38% in total hip prosthesis with the head diameter of 32 mm; and 43% in total prostheses with the head diameter of 28 mm.

The comparison of the range of hip movement of an adult (obtained from the classic book) to that of the total hip prosthesis with a head diameter of 32 mm, the neck of 12/14; and to the necked total hip prosthesis with a head diameter of 32 mm and with the anatomical ratio of head/neck is as follows:

Movement Range of Hip The Neck/Head 12/14 Press-fit

Movement of an Anatomical System Necked

Adult Diameter

Proportioned Neck

Hip Flexion 0 - 135 0 - 120 0 - 170

Hip Extension 0 - 30 0 - 30 0 - 50 - 60

Abduction 0 - 45 0 - 50 0 - 70

Abduction 0 - 30 0 - 30 0 - 60

As seen above, when the neck/head anatomical diameter proportioned neck is used, the range of movement is near the adult's range of hip movement. In prosthesis with 12/14 press-fit system, the range of movement shown in Figure 4b is wide and the locking of the acetabulum lower end (12.2) with the femoral head's apex disappears. In that case, the hip is stabilized by only the muscle balance. In Figure 4b, the head's movement axis (10) direction is shown. As shown in Figure 4b, as the acetabulum lower end shall not get locked with the head (1 ) apex in case of a simple, sudden and uncontrolled movement; it shall cause luxation. In thin necked prostheses, when an unwanted movement (such as stumbling, falling or an uncontrolled movement while standing up or sleeping etc.) is made, luxation shall occur, because the head movement axis (10) of the femoral head (1 ) apex shall not be placed on the lower acetabulum end (12.2) and it shall not get locked when the neck comes to the upper acetabulum end (12.3). In the research made, the acetabulum's head apex can not get locked when the head/neck central line (12.1 ) exceeds 65-70° in total hip prosthesis. However, this angle is above 70° in 12/14 press-fit necked prostheses.

The innovation of the invention is shown in Figure 4a.

In prostheses with anatomically proportioned neck diameter/head diameter, and with a given neck thickness; the range of movement is within that of a normal hip (Figure 4a). When the head extension (1.1 ) leans over the upper end of the acetabulum (12.3), the head's apex cannot skip the acetabulum end. The head (1), the lower end of the acetabulum (12.2) and femoral head extension (1.1 ) get locked and this prevents the luxation of the femoral head (1). The movement axis (11 ) of the limited head in Figure 4a shows the prevented luxation position.

In Figures 4a and 4b, the acetabular range of movement and hip stabilization of the prostheses with a thin neck (with diameters of 12 mm), with a thick head extension (1.1) made according to the head/neck anatomical diameter ratio is shown. The head's movement axis (10) that causes luxation and the limited head movement axis (11 ) with which luxation is prevented are shown in the figures. In Figure 4b, when the neck (2) leans over the upper end of the acetabulum (12.3) in the maximum abduction (the leg's separation from the body) of the thin necked femoral head-neck; the tangent vertically drawn from the femoral head to the central line (2.1 ) does not intersect with the lower end of the acetabulum (12.2). For this reason, the femoral head cannot get locked on the opposite end of the acetabulum and luxation occurs. In tis situation, the abduction angle of the leg from the hip is 70° (12). This angle is 45° in adults. In Figure 4a, in the necks whose anatomical femoral head diameter is proportional to the neck diameter, as the head leans over the upper end of the acetabulum (12.3) in case of the neck's maximum abduction; and as the tangent vertically drawn from the head's (1) apex to the femur-central line (12.1 ) shall intersect with the lower end of the acetabulum (12.2), the head (1) is locked on the lower end of the acetabulum (12.2). As seen in the limited head's movement axis (11 ) the separation of the femoral head (1) from the hole (luxation) is prevented. In this situation, the angle of the leg's abduction from the hip is 45-50° (13). This angle is 45° in adults.

The invention cannot be limited to the figurative applications presented in this part. The main elements in the scope of the protection stated in the Claims being the base, alternative restructurings that may be made by those specialized in the art shall mean the violation of the invention.

Claims

1. The invention is the modular hip prosthesis consisting of a spherical head (1 ), a neck (2) and a stem (3) and is used for the surgical treatment of hip fractures and coxofemoral diseases characterized in that it comprises, - In order to ensure the neck (2) length and off-set adjustment when the said head (1 ) is placed on the neck (2); at least one inner thread (1.2) which ensures the said head's (1 ) adjustment on the neck (2) and which is formed as a thread canal on the inner hull of a cylindrical hole that opens out to the inner part of the said head (1 ), - In order to ensure the neck (2) length and off-set adjustment through rotating the said head (1 ) on the neck (2); at least one neck (2) part, the two ends of which have been connected to the head (1 ) and the stem (3) in a way to enable movement and which is in the form of a cylindrical bar with threads all over the surface, - In order to make the said hip movements stay within the anatomical dimensions and to decrease the risk of hip dislocation, at least one cylindrical head extension (1.1 ) which has been formed on the neck (2) side of the head (1 ), which is in the form to create degrees in the anatomic dimensions between the head (1 ) and the neck (2), and which ensures leaning over the edge of acetabulum and limits the over-angled movement of head (1 )-neck (2).

2. Adjustable modular hip prosthesis according to Claim 1 , characterized in that it comprises a multiple bolt hole (1.3) with bolting threads on which enables the head's (1) stabilization to the neck (2) and which is formed on the said head extension (1.1 ).

3. Adjustable modular hip prosthesis according to the any of the preceding claims, characterized in that it comprises a multiple fixing bolt (1.4) which enables the head's (1 ) stabilization to the neck (2) and which is connected to the said bolt holes (1.3).

4. Adjustable modular hip prosthesis according to the any of the preceding claims, characterized in that the said fixing bolt (1.4) top does not have a cap so that it is embedded in the bolt hole (1.3).

5. Adjustable modular hip prosthesis according to the any of the preceding claims, characterized in that it comprises at least one locknut (6) which moves on the said neck (2) and stabilizes the head (1) on the neck (2).

6. The invention relates to the modular hip prosthesis consisting of a spherical head (1), a neck (2) and a stem (3) and is used for the surgical treatment of hip fractures and coxofemoral diseases characterized in that it comprises,

- at least one angled tip (2.1) formed on the stem (3) side of the said neck (2) and which enables movement within the anatomical angle range in order to enable the adjustment of the anteversion angle according to the stem (3) and the stabilization of the said neck (2),

- at least one neck fixing hole (3.1) which is formed on the neck (2) side of the said stem (3), which enables movement within the anatomical angle range and which ensures the standard angle of 135° between the head (1 )- neck (2) and the stem (3), in order to enable the adjustment of the anteversion angle according to the stem (3) and the stabilization of the said neck (2).

7. Adjustable modular hip prosthesis according to the any of the preceding claims, characterized in that it comprises an angle, namely, X angle created between the said neck (2) and the angled tip (2.1 ).

8. Adjustable modular hip prosthesis according to the any of the preceding claims, characterized in that the direction of the said neck fixing hole (3.1 ) is a Q angle between neck axis (4) and the hole axis (5).

9. Adjustable modular hip prosthesis according to the any of the preceding claims, characterized in that the connection surface of the said angled tip (2.1 ) has the notch form with longitudinal recesses and indents on.

10. Adjustable modular hip prosthesis according to the any of the preceding claims, characterized in that the connection surface of the said neck fixing hole (3.1) has the notch form with longitudinal recesses and indents on.

11. Adjustable modular hip prosthesis according to the any of the preceding claims, characterized in that the anteversion angle of the said threaded neck

(2) and the stem (3) is stable and firmly connected.

12. The invention relates to the modular hip prosthesis consisting of a spherical head (1 ), a neck (2) and a stem (3) and is used for the surgical treatment of hip fractures and coxofemoral diseases characterized in that it comprises

- at least one round shaped pinned stem (8) which is connected to the femur and has longitudinal canals to prevent rotation in the femoral medulla and on the upper part of which the neck (2) can be adjusted and connected through rotating, in order to enable the said prosthesis to become a revision total or trochanteric partial prosthesis when necessary,

- at least one rotatable upper body (2.2) which is formed on the lower part of the said neck (2), accords with the femoral defect and which enables connection to the said pinned stem (8) through adjustment in order to ensure the adjustment of the head's (1 ) anteversion angle and its connection to the pinned stem (8) once the said pinned stem (8) has been placed on the medulla,

- at least one rotatable lower body (2.3) which is formed oh the lower part of the said neck (2), accords with the femoral defect and which enables connection to the said pinned stem (8) through adjustment in order to ensure the adjustment of the head's (1 ) anteversion angle and its connection to the pinned stem (8) once the said pinned stem (8) has been placed on the medulla.

13. Adjustable modular hip prosthesis according to Claim 12 characterized in that, in order to enable the connection of the said rotatable upper body (2.2) or the rotatable lower body (2.3) to the pinned stem (8) and to adjust and apply the anteversion angle, characterized in that it comprises - numerous locknotches on a circular axis which are formed on the connection surface of the said rotatable upper body (2.2) or the rotatable lower body (2.3) to the pinned stem (8) and which enable the angle adjustment,

- numerous body locknotches (2.4) which are formed on the connection surface of the rotatable upper body (2.2) to the pinned stem (8) compatible with the locknotches (8.5) and which enable angle adjustment,

- numerous body locknotches (2.4) which are formed on the connection surface of the rotatable lower body (2.3) to the pinned stem (8) compatible with the locknotches (8.5) and which enable angle adjustment.

14. Adjustable modular hip prosthesis according to Claim 12 and 13 characterized in that, it comprises at least one stem pin (8.6) which is formed on the rotatable upper body (2.2) or the rotatable lower body (2.3) side of the said pinned stem (8).

15. Adjustable modular hip prosthesis according to Claim 13 and 14 characterized in that, in order to ensure that the said rotatable upper body (2.2) or the rotatable lower body (2.3) is connected and locked to the stem pin (8.6) after the anteversion angle is adjusted; it comprises - at least one nut fixing tip (8.3) with threads on which is formed on the upper part of the said stem pin (8.6),

- at least one fixing nut (8.1) which is connected to the nut fixing tip (8.3) and which enables stabilization,

- at least one left bolt fixing hole (8.4) with threads which is formed on the upper part of the said stem pin (8.6) in a hole form,

- at least one left bolt (8.2) which is connected to the left bolt fixing hole (8.4) and which prevents the fixing nut (8.1 ) from loosening.