JOINT DEVICE

Abstract

A joint device of an orthosis with an upper part and with a lower part that is arranged on the upper part in an articulated manner, with a first fastening device for securing the upper part to a patient and a second fastening device for securing the lower part to a limb, wherein the joint device connects the upper part to the lower part in an articulated manner and has an upper part binding and a lower part binding via which the upper part and the lower part can be secured to the fastening devices, wherein the joint device has at least four degrees of freedom.

Claims

1. A joint device of an orthosis, comprising: an upper part; a lower part connected to the upper part in an articulated manner; a first fastening device to secure the upper part to a patient; a second fastening device to secure the lower part to a limb; an upper-part connection and a lower-part connection, via which the upper part and the lower part can be secured to the fastening devices; wherein the joint device has at least four degrees of freedom.

2. The joint device as claimed in claim 1, wherein the joint device has at least three rotational degrees of freedom.

3. The joint device as claimed in claim 1, wherein the joint device has at least one translational degree of freedom.

4. The joint device as claimed in claim 2, further comprising rotation axes for at least two of the rotational degrees of freedom, wherein the rotation axes intersect each other.

5. The joint device as claimed claim 2, wherein a pivot axis of at least one rotational degree of freedom lies outside the joint device.

6. The joint device as claimed in claim 1, wherein at least one degree of freedom is limited via end stops.

7. The joint device as claimed in claim 1, wherein at least one elastic buffer element is assigned to at least one degree of freedom.

8. The joint device as claimed in claim 7, wherein the at least one buffer element is formed by elastomer elements arranged parallel to the rotation axis.

9. The joint device as claimed in claim 7 wherein the at least one buffer element is formed with elastic tensioning elements.

10. The joint device as claimed in claim 7, wherein the joint device is held by the at least one buffer element in a starting position with respect to at least one degree of freedom.

11. The joint device as claimed in claim 1, further comprising an actuator assigned to at least one rotational degree of freedom.

12. The joint device as claimed in claim 11, wherein the actuator is mounted in or on a holder, which is arranged between the upper part and the lower part and has the at least two degrees of freedom.

13. The joint device as claimed in claim 12, wherein the at least two degrees of freedom are rotational degrees of freedom, and rotation axes associated with the rotational degrees of freedom are perpendicular to each other.

14. The joint device as claimed in claim 12, wherein at least one rotational degree of freedom is at least one of formed via an elongate hole guide or limited via bands.

15. An orthosis having an upper part and a lower part, which are connected to each other via a joint device as claimed in claim 1.

16. A joint device of an orthosis, comprising: an upper part; a lower part pivotally connected to the upper part; a first fastening device to secure the upper part to a patient; a second fastening device to secure the lower part to a limb of the patient; an upper-part connection and a lower-part connection, via which the upper part and the lower part can be secured to the fastening devices; wherein the joint device has at least four degrees of freedom.

17. The joint device as claimed in claim 16, wherein the at least four degrees of freedom include at least three rotational degrees of freedom.

18. The joint device as claimed in claim 16, wherein at least four degrees of freedom include at least one translational degree of freedom.

19. The joint device as claimed in claim 17, further comprising rotation axes for at least two of the rotational degrees of freedom, wherein the rotation axes intersect each other.

20. The joint device as claimed claim 17, wherein a pivot axis of at least one rotational degree of freedom lies outside the joint device.

Description

[0021] Illustrative embodiments of the invention are explained in more detail below with reference to the accompanying figures, in which:

[0022] FIG. 1 shows a schematic overall view of an orthosis;

[0023] FIG. 2 shows a perspective view of a joint device without fastening device;

[0024] FIG. 3 shows a variant of FIG. 2, with a modified control appliance;

[0025] FIG. 4 shows a side view of the embodiment according to FIG. 2;

[0026] FIG. 5 shows a front view of FIG. 4;

[0027] FIG. 6 shows a plan view according to FIG. 5;

[0028] FIG. 7 shows a lower-part connection on its own;

[0029] FIG. 8 shows a sectional view through an upper-part connection, and

[0030] FIG. 9 shows a variant of FIG. 8.

[0031] FIG. 1 is a schematic overall view of a hip-knee-ankle orthosis which engages over three joints of the lower extremity, namely the hip joint, the knee joint and the ankle joint. In the region of the natural hip joint and in the region of the natural knee joint, a respective joint device 10, 10 is arranged between an upper part 1, 1 and a lower part 2, 2, respectively. The respective upper part 1, 1 is fitted on the patient via a first fastening device 3, 3, and the respective lower part 2, 2 is fastened, via a second fastening device 4, 4, to the limb located distally with respect to the respective joint device 10, 10. The orthosis thus has two upper parts 1, 1. The first upper part 1 is fastened to the trunk of the patient via a pelvic strap or a hip strap 3. The associated lower part 2 is fastened to the upper leg via an upper-leg shell or upper-leg rail and a fastening strap as fastening device 4. The upper-leg shell together with the fastening device 4 at the same time forms a second upper part 1, which is secured to the upper leg via a first fastening device 3 provided for this purpose. Of course, the upper-leg shell is moreover connected to the upper leg moreover with the second fastening device 4 to the first upper part 1. A lower-leg rail is arranged as second lower part 2 distally with respect to the upper-leg shell or upper-leg rail, which second lower part 2 can be secured to the lower leg via a strap as second fastening device 4. The lower-leg rail has a foot plate on which the foot is supported. The upper-leg shell with the associated fastening devices is thus both first lower part 2 and second upper part 1 in the use as an orthosis provided with two joint devices 10, 10.

[0032] FIG. 2 shows a perspective view of a joint device 10 as part of an orthosis which can be arranged on a patient so as to engage over the joints. The joint device 10 has an upper part 1, above a first rotation axis 210, and a lower part 2, wherein the upper part 1 has an upper-part connection 11 for securing to a first fastening device (not shown) on the pelvis of a patient. The lower part 2 has a lower-part connection 12 which can be fastened to a second fastening device in order to secure the lower part 2 to an upper leg. The upper-part connection 11 is provided with a base plate 110 in which bores 111 are arranged through which the upper-part connection 11 can be secured to the first fastening device. The securing can be effected via screws, for example. Two walls 112 extend from the base plate 110, wherein the two walls 112 are oriented substantially parallel to each other and are aligned perpendicularly with respect to the base plate 110. Inside each wall 112, an elongate hole guide 113 is formed which is designed as a partial arc of a circle or at least curved, wherein the radius of the elongate hole guide 113 is such that the midpoint lies outside the upper-part connection 11.

[0033] A sliding pin 151 is guided inside the elongate hole guide 113 and connects the upper-part connection 11 to a holder 50, which is of a multi-part design. The sliding pin 151 connects the holder 50 to the upper-part connection 11 reversibly. For this purpose, the sliding pin 151 is insertable into the elongate hole guide 113 and removable. The sliding pin 151 is guided through the elongate hole guide 113 and through a bore or an elongate hole 5111 in a web 511. The web 511 is part of a frame 51, which is in turn part of the holder 50. The frame 51 is substantially U-shaped and forms a rotary bearing via its side branches, such that a housing 52, which is a second part of the holder 50, is mounted rotatably about the rotation axis 210. The rotation axis 210 is substantially perpendicular to the sagittal plane and permits a pivoting movement of the lower part 2 inside the sagittal plane, such that a leg can swing forward and backward when an orthosis is fitted on the hip or the pelvis.

[0034] The housing 52, as part of the lower part 2, serves to receive an actuator 40, which can be configured as a damper and/or drive. The housing 52 can be part of an actuator housing or can consist entirely of the actuator housing. Laterally, i.e. on that side of the housing 52 directed away from the upper-part connection 11, a control device 41 is arranged which is coupled to sensors (not shown) and evaluates sensor data recorded by sensors and conveys these to an adjustment device or a motor control appliance, such that either damper properties are changed or a drive is activated or deactivated.

[0035] Distally with respect to the upper-part connection 11, a lower-part connection 12 with a base plate 120 and with bores 121 arranged in the latter is arranged on the medial side of the housing 52 directed toward the patient. By way of the base plate 120 and the bores 121, the lower-part connection 12 is secured to the second fastening device (not shown), such that the lower part 2 can be secured to the upper leg of the patient during use of the joint device as a hip joint.

[0036] It is possible via the joint device 10 to pivot the frame 51 about a rotation axis 230, since the frame 51 is guided inside the elongate hole guide 113 along a portion of an arc of a circle. The rotation axis 230 lies outside the joint device 10. The radius of the elongate hole guides 113 is preferably chosen such that the rotation axis 230 lies inside the hip joint, preferably in the anatomical hip rotation point.

[0037] The housing 52 and thus the entire lower part 2 is mounted pivotably on the frame 51 about the rotation axis 210.

[0038] In addition, the lower part 2 is arranged in the frame through an elongate hole guide 5111 so as to be displaceable along the rotation axis 210 in the lateral and medial directions, as is indicated by the double arrow 22, which represents a translational degree of freedom. The displaceability along the rotation axis 210, i.e. in the medial-lateral direction, is limited by end stops, for example by the elastic buffer elements 60 shown in FIG. 8, such that only a limited displaceability within the side branches of the frame 51 is permitted. As an alternative to a displaceability between the side branches, the displaceability can be effected by a resilient mounting of the web 511 between the walls 112 by means of an elastic mounting of the sliding pin 151. Alternatively, the lower-part connection can be mounted on the housing 52 so as to be longitudinally displaceable along the longitudinal extent of the housing 52, i.e. in the proximal-distal direction of the lower leg, as is indicated by the double arrow 25, which represents a translational degree of freedom. Here too, end stops are able to limit the displaceability of the lower-leg connection 12 relative to the housing 52. The lower-part connection 12 is additionally mounted pivotably pivotably about a rotation axis 240 which runs in the proximal-distal direction, i.e. in the longitudinal extent of the housing 52, as will be explained further below. Thus, the joint device 1 has a total of three rotational degrees of freedom 21, 23 and 24, which permit a rotatability of the components relative to one another about the rotation axis 210, the rotation axis 230 and the rotation axis 240. In addition, a translational degree of freedom 22 is present within the joint device 1, namely in the medial-lateral direction, by the displaceability within the side branches of the frame 51.

[0039] FIG. 3 shows a variant of the joint device 10 with the same mechanical set-up but with a control device 41 arranged at the front, by means of which it is possible for the joint device 10 to be designed narrower in the medial-lateral direction than in the variant according to FIG. 2. It will be seen in FIG. 3 that the sliding pin 151, which connects the frame 51 to the upper-part connection 11, lies at the height of the rotation axis 210, such that the rotation axes 230 and 210 intersect each other at one point.

[0040] FIG. 4 shows a side view of the joint device 10 according to FIG. 2, in which the orientation of the rotation axes 230 and 240 at right angles to each other can be seen. The figure also shows the actuator 40, which has an upper articulation point 45 spaced apart from the rotation axis 210. In the embodiment shown, a lower articulation point 46 of the actuator 40 in the housing 52 of the lower part 2 is located in alignment with the rotation axis 240 of the lower-part connection 12. By a pivoting about the rotation axis 240 along the rotational degree of freedom 21, the distance of the upper articulation point 45 from the lower articulation point 46 changes, such that the actuator, for example as a hydraulic damper, experiences a relative movement between piston and cylinder in a longitudinal direction. In the case of a damper, a resistance to the relative movement is provided by corresponding hydraulic resistances. For a drive, the actuator 40 is supplied externally with energy and, by means of a motor, causes the two articulation points 45, 46 to move toward each other or away from each other.

[0041] FIG. 5 shows a front view of the joint device 10 with the laterally arranged control device 41, and with the upper-part connection 11 arranged medially with respect to the housing 52 and the frame 51. The web 511 is fitted between the walls 112 of the upper-part connection 11 and is held by the sliding pin 151. The frame 51 can be displaced relative to the upper-part connection 11 along the degree of freedom 22. Alternatively, the housing 52 can be displaced inside the frame 51 along the rotation axis 210 in the medial-lateral direction, in order to form the translational degree of freedom 22.

[0042] Medially on the housing 52, the lower-part connection 12 is arranged pivotably about a rotation axis 240. Buffer elements 34, which are arranged as cord-shaped elastomer elements parallel to the rotation axis 240, serve on the one hand as an end stop and on the other hand as a restoring element, so as not only to form the rotational degree of freedom 24 about the rotation axis 240 but also to restore to the starting position shown. The starting position or the angle position of the end stops can be defined via the geometric configuration of the buffer elements 34, e.g. via their diameter. In addition, the elastic behavior about this degree of freedom can be influenced by the geometry and the material properties of the buffer elements 34.

[0043] FIG. 6 is a plan view of the joint device according to FIG. 5, showing that the rotation axis 230, about which pivoting is possible through the elongate hole guides 113, lies laterally with respect to the upper-part connection 11 and thus outside the joint device 10. The rotation axis 210 is perpendicular to the rotation axis 230.

[0044] FIG. 7 shows a detail of the lower-part connection 12 with the bores 121 for securing to the fastening device (not shown). Inside the base plate 120, recesses 124 are formed in the shape of channels, between which a bore or sleeve 125 is arranged. Inside the bore 125 runs the rotation axis 240, about which the lower-part connection 12 can be pivoted relative to a fastening plate 521 which can be secured to the housing 52 of the lower part 2 via the illustrated bores and screws. The fastening plate 521 can also be seen in FIG. 5.

[0045] The joint device 10 is kinematically indeterminate as a result of the configuration with at least four degrees of freedom; the orthosis system becomes kinematically determinate only when fitted to the user. In the example shown, the rotation axis 210 normal to the sagittal plane is automatically positioned through the physiological joint, in this case the hip joint. Despite the positioning of the joint device 10 outside the body, the rotation axis 230 runs normal to the frontal plane through the physiological rotation point, which avoids constraints and resulting longitudinal loads. The exact determination of the anatomical rotation point of the natural hip joint is extremely difficult. By means of a joint device 10 as described above, an exact positioning is no longer necessary with the orthosis applied rigidly to the human body, since an automatic positioning over the physiological rotation point is effected on account of the available degrees of freedom.

[0046] By means of the removable sliding pin 151, it is possible for the joint device 10 to be designed to be easily assembled and disassembled in order to cancel and again restore the mutual association of the components of the joint device 10. In the illustrative embodiment, by the removal of the sliding pin 151, the upper-part connection 11 can be easily separated from the other components of the joint device 10 and secured thereon again, as a result of which it is considerably easier to apply the pelvic strap and separately apply, for example, an upper-leg rail, or an upper-leg rail with attached lower-leg rail and foot part. Specifically in the case of a hip-joint connection with an attached orthosis engaging over the knee joint and the ankle joint, assembly is otherwise very difficult, since both the ankle joint and the knee joint, and also the hip joint, have to be oriented within the orthosis, and the orthosis has to be secured to the leg. By canceling the association of the components and by being able to easily restore said association, the fitting of the orthosis can be made substantially easier.

[0047] The joint device 10 is stabilized in its basic position by the buffer elements 34. Passive-elastic properties can be defined by the choice of geometry and the material properties of the buffer elements 34. A shallow overall height is obtained, wherein the lower-part connection 12 can be designed laterally offset with respect to the upper-part connection 11, so as to be able to compensate for distance differences in the medial-lateral direction of the particular patient and in the mechanical configuration of the upper part 1 and of the lower part 2. With a shallow overall height in the medial-lateral direction, the joint device 10 permits great flexibility in terms of the adjustability of the desired neutral position and a high torsional stiffness. The neutral position and the torsional stiffness can be defined by the diameter, the contact length and the elastic properties of the respective buffer elements 34.

[0048] The change of the effective length of the buffer elements 34 can be easily realized in design terms by a suitable shaping and a possibility of displacement inside the channels 124, as a result of which the rotatability and the torsional stiffness about the rotation axis 240 can be adjusted easily and steplessly.

[0049] The functionality of the hip connection is achieved by means of the translational degrees of freedom in the sagittal plane being blocked. Moreover, the translational degree of freedom normal to the sagittal plane is in principle free, but limited by end stops. When the orthosis is fitted in place, this additional degree of freedom aligns the functional rotation point of the joint device 10 with the anatomical hip rotation point. The rotational degree of freedom in the frontal plane is passively stabilized. Through the adaptation of the restoring, passive elements or buffer elements 34, the stiffness can be optimally adjusted for the particular user. The possibility of movement normal to the sagittal plane, limited by the end stops 134 or the boundary of the elongate hole 5111, permits a deviation of the distance of the physiological rotation point from the radius predefined by the joint device 10, which radius derives from the radius of the elongate hole guide 113. This permits simple adaptation by the orthopedic technician. The separability of the upper-part connection from the remaining part of the joint device 10 is achieved by the sliding pin 151, which is guided through a stabilization nut 152 in the web 511, on which stabilization nut 152 elastic end-stop elements 134 engage, which counter a displacement in the medial-lateral direction.

[0050] The leg rotation is stabilized by the buffer elements 34 in the basic setting thereof and, on account of their structure, has great flexibility in terms of the desired torsional stiffness. The design of the joint device is such that the rotation is permitted with a very shallow compact structure, which has a very positive impact on the medial-lateral extent of the overall structure of the orthosis.

[0051] FIG. 8 shows a sectional view through an upper-part connection 11 with the arc-shaped elongate hole 113 which is formed therein and in which the web 511 is guided via the sliding pin 151. The frame 51 and the housing 52 (which is shown only in part) are fastened to the web 511 and coupled to the upper-part connection 11. Inside the web 511, an elongate hole 5111 is formed via which a medial-lateral movement according to the double arrow 22 is permitted. End stops or elastic buffer elements 60 can be arranged in the elongate hole 5111 in order, on the one hand, to permit an orientation in a desired zero setting and, on the other hand, to permit an elastic displaceability in the medial-lateral direction or in respect of the translational degree of freedom 22.

[0052] FIG. 9 shows a variant of FIG. 8, in which the sliding pin 151 is assigned elastic elements 61 which are functionally connected to the sliding pin 151. In this way, both the sliding pin 151 and the web 511 are held elastically in a zero setting inside the elongate hole 113. A displacement inside the elongate hole 113 is still possible. The elastic elements 61 can also limit the displacement movement inside the elongate hole 113 before the respective ends of the elongate hole 113 are reached. Instead of elastic elements 61, rigid bands, preferably of adjustable length, can also be assigned to the sliding pin 151, in order to ensure a stop limitation and an adjustment of the pivoting angle.