PROSTHESIS AND ORTHOSIS

Abstract

A prosthesis comprises a housing (100); a piston (221) and piston rod (222) housed within a cylinder of the housing (100); and a pump (244) mounted on and partially within the housing (100). The housing (100) is a unitary piece and comprises a plurality of passages (151, 152, 153, 154) connecting the cylinder to the part of the housing (100) where the pump (244) is mounted.

Claims

1. A prosthesis or orthosis housing, comprising: a cylinder configured to receive a piston of a piston and cylinder assembly; a pump section configured to receive part of a pump; and a plurality of passages connecting the cylinder to the pump section, wherein the prosthesis housing is a unitary piece.

2. A prosthesis housing as claimed in claim 1, wherein the prosthesis housing is an ankle prosthesis housing and further comprises a foot attachment section configured for attaching the housing to a foot component.

3. A prosthesis or orthosis housing as claimed in claim 1, further comprising one or more apertures configured to receive one or more respective valves for controlling fluid flow through one or more of the passages.

4. A prosthesis or orthosis housing as claimed in claim 3, wherein one or more of the valves is an adjustable orifice valve.

5. A prosthesis or orthosis housing as claimed in claim 3, wherein one or more of the valves is a check valve.

6. A prosthesis or orthosis housing as claimed in claim 1, further comprising an aperture configured to receive a switch to be fluidly connected to one of more of the passages such that the switch switches the prosthesis housing between first and second modes of operation.

7. A prosthesis or orthosis housing as claimed in claim 6, wherein the switch to be received in the aperture is a solenoid.

8. A prosthesis or orthosis housing as claimed in claim 1, wherein the pump section is configured to receive two gears of a gear pump and further comprises means for mounting the remainder of the pump on the housing.

9. A prosthesis or orthosis housing as claimed in claim 1, wherein a plurality of the passages are devoid of bends having a radius of curvature of less than half of the passage width or diameter.

10. A prosthesis or orthosis housing as claimed in claim 9, wherein a plurality of the passages are devoid of any bends having a radius of curvature of less than a third of the passage width or diameter and preferably less than a quarter of the passage width or diameter.

11. A prosthesis or orthosis housing according to claim 1, wherein the housing is composed of a material having a microstructure indicative that it has been made using additive manufacturing.

12. A prosthesis or orthosis comprising: a housing as claimed in claim 3; a piston and piston rod housed within the cylinder of the housing; and a pump mounted to the housing.

13. A prosthesis or orthosis as claimed in claim 12, further comprising one or more adjustable orifice valve.

14. A prosthesis or orthosis comprising: a housing as claimed in claim 4; a piston and piston rod housed within the cylinder of the housing; a pump mounted to the housing; and one or more check valve.

15. A prosthesis or orthosis comprising: a housing as claimed in claim 7; a piston and piston rod housed within the cylinder of the housing; a pump mounted to the housing; and a solenoid.

16. A prosthesis comprising: a housing as claimed in claim 2; a piston and piston rod housed within the cylinder of the housing; a pump mounted to the housing; and a foot component.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The present invention will now be described by way of example only, and with reference to the accompanying drawings in which:

[0041] FIG. 1 is a front view of a first embodiment ankle prosthesis housing;

[0042] FIG. 2 is a first side view of the housing of FIG. 1;

[0043] FIG. 3 a back view of the housing of FIG. 1;

[0044] FIG. 4 is a second side view of the housing of FIG. 1;

[0045] FIG. 5 is a top view of the housing of FIG. 1;

[0046] FIG. 6 is a lower view of the housing of FIG. 1;

[0047] FIG. 7 is a first horizontal cross-section corresponding to line A-A in FIG. 2;

[0048] FIG. 8 is a second horizontal cross-section corresponding to line B-B of FIG. 4;

[0049] FIG. 9 is a third horizontal cross-section corresponding to line C-C of FIG. 4;

[0050] FIG. 10 is a vertical cross-section corresponding to line D-D of FIG. 3;

[0051] FIG. 11 is a first side view of an embodiment of a lower limb prosthesis assembly containing the first embodiment ankle prosthesis housing of FIG. 1;

[0052] FIG. 12 is a second side view of the prosthesis assembly of FIG. 11;

[0053] FIG. 13 is a partial cross-section through the prosthesis assembly of FIGS. 11 and 12;

[0054] FIG. 14 is a hydraulic circuit corresponding to the prosthesis assembly of FIGS. 11 and 12;

[0055] FIG. 15 is a first perspective view of a first embodiment knee orthosis; and

[0056] FIG. 16 is a second perspective view of the knee orthosis of FIG. 15.

DETAILED DESCRIPTION OF THE DRAWINGS

[0057] FIGS. 1 to 6 are respective: front; first side; back; second side; top; and lower views of a first embodiment ankle prosthesis housing 100.

[0058] The first embodiment ankle prosthesis housing 100 comprises three main sections: a piston and cylinder assembly (PACA) section 120, an ankle flexion pivot interface section 130, and an accessory interface section 140.

[0059] The PACA section 120 comprises an outer wall 122 which defines a first, lower cylinder and a second upper cylinder. The first, lower cylinder has a diameter less than the second, upper cylinder and is configured to receive a piston and piston rod.

[0060] The first, lower cylinder comprises a cylindrical wall 122 and a circular base portion 121. An aperture 125 is formed in the base 121 of the first, lower cylinder. The aperture 125 is configured to receive a piston rod which extends from a piston slidably mounted in the first, lower cylinder. A first port 126 is formed in the base 121 of the first, lower cylinder. A second port 127 is formed in an upper portion of the first, lower cylinder.

[0061] The second, upper cylinder is configured to receive a cap which closes the top of the first, lower cylinder. The cap includes means for attaching the ankle prosthesis housing 100 to a shin component, such as a pyramid alignment interface or a shin clamp.

[0062] Flexion pivot interface section 130 is configured so that the first embodiment ankle prosthesis housing 100 can be pivotally attached to a foot component 230 (partially shown in FIGS. 11 and 12). As shown in FIGS. 1 to 4, the flexion pivot interface section 130 comprises a hollow cylindrical rod 132 and a bridging piece 134. Cylindrical rod 132 is configured to receive a connecting piece attached to the foot component 230, so that the foot component 230 can be attached to the cylindrical rod 132, whilst being at least partially free to rotate about a central axis of cylindrical rod 132. Bridging piece 134 is configured to connect the cylindrical rod to the PACA section 120. As shown in FIG. 1, bridging piece 134 comprises an outer rim 135 and a supporting section or plurality of supporting struts 136. The outer rim 135 substantially defines a water-droplet shape as shown in FIG. 1. The supporting section or struts 136 is elongate and configured to connect one part of the outer rim 135 to another part of the outer rim 135. The supporting section or struts are configured such that they can translate a force from one side of the outer rim 135 to an opposite side of the outer rim 135. The supporting struts 136 are arranged such that they define an aperture or series of apertures 137. The supporting struts 136 are arranged in a regular arrangement, such as the grid arrangement shown in FIG. 1. Although a regular array of apertures has been shown, any suitable arrangement, shape, or size of aperture 135 may be used. This structure of the flexion pivot interface section 130 provides the section 130 with structural strength whilst minimising its weight.

[0063] The accessory interface section 140 is configured such that one or more ankle prosthesis housing accessories may be attached thereto. Ankle prosthesis housing accessories may include, but are not limited to: a pump; a gear arrangement; an actuator; a motor; a sensor; an inertial measurement unit (IMU); an electronic component; a valve; and an accumulator. As best seen in FIGS. 4 and 5, the accessory interface section 140 comprises an actuator interface section 142. The actuator interface section 142 is configured such that a solenoid (shown in FIG. 12) can be attached thereto. The actuator interface section 142 comprises a platform section 143. Platform 143 is substantially planar. Platform 143 defines an aperture 144 for receiving part of the solenoid. The accessory interface section 140 also comprises a pump interface section 146. Pump interface section 146 comprises a pump section which is configured to receive a part of a pump, such that the pump interface section 146 and the part of a pump attached thereto together form the pump. The pump interface section 146 defines a cavity, configured to receive a pair of gears which together form a gear pump. As shown in FIG. 5, such a cavity defines first and second gear casings 147, each gear casing having a respective aperture configured to receive a gear driver or gear attachment. The accessory interface section 140, as best seen in FIG. 3, further includes a first valve opening 191, a second valve opening 192 and a third valve opening 193.

[0064] The first embodiment ankle prosthesis housing 100 is configured such that accessories attached to the accessory interface section 140 are fluidly connected to other sections of the first embodiment ankle prosthesis housing 100, through the first embodiment ankle prosthesis housing 100. The term fluidly connected as used herein refers to a connection along which fluid, such as hydraulic fluid, can pass. As an example, one end of a hollow tube is fluidly connected to an opposite end of a hollow tube, so that fluid can pass within the tube from one end to the other. The first embodiment ankle prosthesis housing 100 achieves such fluid connections by provision of a series of passages. The first embodiment ankle prosthesis housing 100 is configured or adapted to have one or more curved fluid passages. The first embodiment ankle prosthesis housing 100 is configured or adapted to have one or more fluid passages which are devoid of any sharp bends such as a right angle. The one or more fluid passages may be devoid of any bends having a radius of curvature of less than half of the passage width or diameter.

[0065] The one or more fluid passages may be devoid of any bends having a radius of curvature of less than a third of the passage width or diameter. The one or more fluid passages may be devoid of any bends having a radius of curvature of less a quarter of the passage width or diameter. The one or more fluid passages may be devoid of any bends having a radius of curvature of less than a tenth of the passage width or diameter.

[0066] As shown in FIGS. 1 to 10, the first embodiment ankle prosthesis housing 100 comprises: a first passage 151, a second passage 152, a third passage 153, and a fourth passage 154.

[0067] First passage 151 is configured to fluidly connect components attached to the accessory interface section 140 to each other. As best seen in FIG. 7, first passage 151 is configured to fluidly connect the first valve opening 191 to second valve opening 192.

[0068] Second passage 152 is configured to fluidly connect PACA section 120 to accessory interface section 140. As best seen in FIG. 8, second passage 152 is configured to fluidly connect second port 127 to a third port 148.

[0069] Third passage 153 is configured to fluidly connect PACA section 120 to accessory interface section 140. As best seen in FIGS. 2, 5, and 8, third passage 153 is configured to fluidly connect first port 126 to a fourth port 149.

[0070] Fourth passage 154 is configured to fluidly connect components attached to the accessory interface section 140 to the PACA section 120. As best seen in FIGS. 9 and 10, fourth passage 154 is configured to fluidly connect aperture 144 to a sixth port 128.

[0071] The first embodiment ankle prosthesis housing 100 is a single unitary piece of metal or alloy, i.e., is formed/manufactured as a single piece/part/manifold without joints. However, as a skilled person will appreciate, the first embodiment ankle prosthesis housing 100 is not limited to these materials and any appropriate material can be used. Suitable metals and alloys include: titanium; aluminum; stainless steels. The first embodiment ankle prosthesis housing 100 is formed using an additive manufacturing technique, such as but not limited to: material jetting, binder jetting, extrusion, and powder bed fusion. Since the housing is made using additive manufacturing its material has a microstructure indicative that it was made by additive manufacturing, i.e., it is apparent from inspection of the housing that the housing has been manufactured using an additive manufacturing method. Furthermore, since the manufacture of the housing by additive manufacturing includes formation of the passages and apertures within the housing as part of the additive manufacturing process, whereas traditionally passages and apertures are drilled into a cast or machined block or manifold. Such a process requires steps to be taken after the manifold is initially formed to create the passages, and these passages, when drilled, will be formed of straight runs which join at harsh angles. Some or all of these straight runs will need to be sealed with plugs, which may leak. In contrast, by forming the housing of the present invention as a unitary manifold/housing there is no need to take additional steps of drilling passages and these passages can include more gentle curves, thereby providing less resistance to fluid flow. Additionally, by using additive manufacturing the physical location and proximity of sections of the housing can be optimised.

[0072] The first embodiment ankle prosthesis housing 100 may have been subjected to a form of post-processing strengthening treatment, including but not limited to heat treatment. The first embodiment ankle prosthesis housing 100 may also have been subjected to a form of surface finishing treatment. The skilled person will readily understand that notwithstanding the prosthesis housing described herein is an ankle prosthesis housing, the teachings of this application can be applied to produce a housing of a knee or other prosthesis or orthosis.

[0073] As shown in FIGS. 11 and 12, the first embodiment ankle prosthesis housing 100 is configured for attachment to prosthesis assembly components to form an ankle prosthesis assembly 200. The prosthesis assembly 200 further includes a foot component 230, a piston assembly 220, and one or more accessory components 240.

[0074] The one or more accessory components 240 include a motor 242, a pump 244, a solenoid component 246, and adjustable and non-return valves as shown in FIGS. 11-13.

[0075] Motor 242 is attached to pump 244, and configured such that actuation of motor 242 drives the pump 244. As shown in FIG. 12, pump 244 is at least partially integrated into the first and second gear casings 147 of the first embodiment ankle prosthesis housing 100.

[0076] The pump 244 is fluidly connected by means of second passage 152 to piston the assembly 220. Specifically, the pump 244 is fluidly connected by means of second passage 152 to a first side of piston assembly 220. In the present embodiment the first side of the piston assembly 220 is an upper side of the piston 221. The piston assembly 220 is shown in FIG. 13, in which the piston rod 222 passes through the aperture 125 in the base 121 of the first, lower cylinder of the PACA section 120.

[0077] The pump 244 is fluidly connected by means of third passage 153 to piston assembly 220. Specifically, the pump 244 is fluidly connected by means of third passage 153 to a second side of piston assembly 220. In the present embodiment the second side of the piston assembly 220 is a lower side of the piston 221.

[0078] The solenoid component 246 is fluidly connected to the pump 244 and piston assembly 220 by means of the fourth passage 154.

[0079] FIG. 14 shows a hydraulic circuit 500 corresponding to the prosthesis assembly 200 shown in FIGS. 11 to 13. The hydraulic circuit 500 comprises a piston assembly 220 having a piston 221 and piston rod 222. The hydraulic circuit 500 also comprises a motor 242, pump 244, and a solenoid component 246.

[0080] The hydraulic circuit 500 also comprises accumulator 551, a first adjustable orifice 552, a second adjustable orifice 553, a first check valve 554, a second check valve 555, a third check valve 556, first pressure transducer 557, second pressure transducer 558, and foot component 230. The first adjustable orifice 552 is disposed within the third valve opening 193 and provides variable dorsiflexion resistance. The second adjustable orifice 553 is disposed within the second valve opening 192 and provides variable plantarflexion resistance. The hydraulic circuit also comprises first hydraulic line 501, second hydraulic line 502, third hydraulic line 503, and fourth hydraulic line 504.

[0081] First hydraulic line 501 corresponds to fourth passage 154. Third hydraulic line 503 corresponds to first and second passages 151, 152.

[0082] First valve opening 191 is configured to receive third check valve 556. Second valve opening 192 is configured to receive second adjustable orifice 553. Third valve opening 193 is configured to receive first adjustable orifice 552.

[0083] The prosthesis assembly 200 comprises four main operating modes, two of which are active (i.e. receive an energy input from the motor 242) and two of which are passive (i.e. where the motor 242 is not engaged). Switching between the active and passive modes is achieved by actuating the solenoid 246.

[0084] The first mode is passive plantarflexion (PPF) mode. The ankle prosthesis assembly 200 is configured to operate in the first mode following heel strike when the prosthesis assembly is in use. In this mode, the solenoid 246 blocks its hydraulic path, so that fluid cannot flow through the first hydraulic line 501, the solenoid component 246 or through the first adjustable orifice 552. In this mode, the piston 221 and piston rod 220 move within the cylinder upwards (to the right hand side of the schematic shown in FIG. 14) under force applied by the amputee to the heel. This causes fluid to flow through the fourth hydraulic line 504, through the third hydraulic line 503, and through the second hydraulic line 502 to the underside (left hand side as shown in FIG. 14) of the piston 221. In other words, the hydraulic fluid is pushed by the piston 221 to flow anticlockwise, primarily through the second adjustable orifice 553 (variable plantarflexion resistance valve) and past the third check valve 556, with some hydraulic fluid driving the pump 244. The motor 242 may be configured to prevent this from happening, to prevent the pump 244 from being back-driven.

[0085] The second mode is passive dorsiflexion (PDF) mode. In this mode the piston 221 is driven to the left in FIG. 14 as the amputee continues the gait cycle with the shin component moving over the foot component 230. In this mode, the solenoid 246 is unblocked, so that fluid can flow through the solenoid component 246, through the first adjustable orifice 552 (variable dorsiflexion resistance valve), and through the first hydraulic line 501. The fluid is prevented from flowing through the second adjustable orifice 553 by the third check valve 556. In this mode, the piston 221 and piston rod 220 are caused to move within the cylinder, downwards (to the left hand side of the schematic shown in FIG. 14). This causes fluid to flow through first hydraulic line 501, to the upper (right hand side as shown in FIG. 14) of the piston 221. In other words, the hydraulic fluid is pushed by the piston 221 to flow clockwise, primarily through the solenoid 246 and first adjustable orifice 552 (variable dorsiflexion resistance valve), with some hydraulic fluid driving the pump 244 through third hydraulic line 503 and through fourth hydraulic line 504. The motor 242 may be configured to prevent the pump from being back-driven.

[0086] The third mode is active plantarflexion (APF) mode. The prosthesis assembly 200 is configured to operate in the third mode towards the end of the stance phase, and can be used to rotate the shin component about the foot carrier 230, before toe-off. In this mode, the solenoid 246 is blocked, so that fluid cannot flow through the first hydraulic line 501, through solenoid component 246 or through first adjustable orifice 552. In this mode, motor 242 actuates pump 244, which forces fluid through third hydraulic line 503, and causes the piston 221 and piston rod 220 to move within the cylinder, upwards (to the right hand side of the schematic shown in FIG. 14). This causes fluid to flow through fourth hydraulic line 504, from the upper (right hand side as shown in FIG. 14) of the piston 221.

[0087] The fourth mode is active dorsiflexion (ADF) mode. This occurs during the swing phase to lift the toe as the foot swings forward. In this mode, the solenoid component 246 is blocked, so that fluid cannot flow through the first hydraulic line 501, through solenoid component 246 or through first adjustable orifice 552. In this mode, motor 242 actuates pump 244 in the opposite direction to which it is driven in the third mode, which forces fluid through fourth hydraulic line 504, and causes the piston 221 and piston rod 220 to move within the cylinder, downwards (to the left hand side of the schematic shown in FIG. 14). This causes fluid to flow from the lower (left hand side as shown in FIG. 14) of the piston 221, through third hydraulic line 503 back to the pump 244. Some fluid may flow through second hydraulic line 502 and the second adjustable orifice 553 in this mode.

[0088] Due to the arrangement shown by the hydraulic circuit in FIG. 14, there are losses when ADF occurs by bypass flow through second hydraulic line 502, through second adjustable orifice 553 and third check valve 556, but not when APF occurs.

[0089] Although a dry prosthesis assembly 200 has been shown in FIGS. 11 and 12, it should be understood that features of the prosthesis assembly 200 could be configured to provide a wet system, i.e., one in which movable components are surrounded by an outer housing, in which oil or a suitable fluid is held.

[0090] Although a specific form and arrangement of ankle prosthesis and ankle prosthesis housing is shown in the Figures, it will be appreciated that various aesthetic, structural, dimensional and spatial changes could be made to the device shown whilst still performing the function of the present invention as defined in the appended claims.

[0091] The principles governing the arrangement of the ankle prosthesis housing described above can also be applied to other prostheses and orthoses. One example of such an orthosis is a knee orthosis 300, shown in FIGS. 15 and 16.

[0092] The orthosis shown in FIGS. 15 and 16 comprises a housing 400. Housing 400 comprises an upper connection section 420, a lower connection section 430, and an accessory interface 440.

[0093] Similar to the first embodiment ankle prosthesis housing 100 described above, sections of the housing 400 are fluidly connected to each other by means of fluid passages. Similar to the first embodiment ankle prosthesis housing 100 described above, the housing 400 is configured or adapted to have one or more curved fluid passages. The knee orthosis housing 400 is configured or adapted to have one or more fluid passages which are devoid of any sharp bends. The one or more fluid passages may be devoid of any bends having a radius of curvature of less than half of the passage width or diameter. The one or more fluid passages may be devoid of any bends having a radius of curvature of less than a third of the passage width or diameter. The one or more fluid passages may be devoid of any bends having a radius of curvature of less a quarter of the passage width or diameter. The one or more fluid passages may be devoid of any bends having a radius of curvature of less than a tenth of the passage width or diameter. As shown in FIG. 16, there may be a first knee passage 451, a second knee passage 452, and a third knee passage 453.

[0094] Similar to the first embodiment ankle prosthesis housing 100 described above, the knee orthosis housing 400 may be a single unitary piece of metal or alloy. The knee orthosis housing 400 is not limited to these materials and any appropriate material can be used. Suitable metals and alloys include: titanium, aluminium, stainless steel. The knee orthosis housing 400 may be formed using an additive manufacturing technique, such as but not limited to: material jetting, binder jetting, extrusion, and powder bed fusion. The knee orthosis housing 400 may have been subjected to a form of post-processing strengthening treatment, including but not limited to heat treatment. The knee orthosis housing 400 may also have been subjected to a form of surface finishing treatment.

[0095] Although a specific form and arrangement of ankle prosthesis and knee orthosis housing is shown in the Figures, it will be appreciated that various aesthetic, structural, dimensional and spatial changes could be made to the device shown whilst still performing the function of the present invention as defined in the appended claims.