The present embodiments generally relate to hand orthoses, and in particular to inflatable bladder hand orthoses.
Orthoses are externally applied devices that can be used to modify or support structural and/or functional characteristics of the neuromuscular and skeletal system. Orthoses may be used in various applications to control, guide, limit or immobilize an extremity, a joint and/or a body segment of a human subject.
For instance, U.S. Pat. No. 5,020,515 discloses an inflatable hand splint for treatment of human subjects with arthritic or stroke paralyzed writs. The inflatable hand splint is disclosed as being easily applied under the subject's fingers between the finger tips and the palmer region of the hand. By inflating an air bladder of the inflatable hand splint, the fingers are gently moved outward from the palmer region repeatedly on a scheduled basis to prevent fixation of the fingers in a contorted position.
U.S. Pat. No. 5,056,504 discloses an inflatable ball hand splint comprising a pliable wrist element with an inflatable ball attached at a first end. The second end of the wrist element extends downwardly along the underside of the subject's wrist and is strapped to the subject's forearm with a pair of straps. A front end of a hard plastic support member is inserted between the fingers and the palmar region of the subject's hand. The rear end of the support member is located below the pliable wrist element and is also strapped to the subject's forearm.
U.S. Pat. No. 5,437,620 discloses a wrist splint comprising a splint platform, at least one bladder receptacle member slidingly engaged with the splint platform and at least one air bladder. Each air bladder is coupled to one of the bladder receptacle members.
There is, however, still a need for improvements within the technical field of inflatable hand orthoses and in particular for human subjects having spasticity and/or contractures in the wrist, hand and/or digits, such as following a neurological disease or cerebrovascular accident (CVA).
It is a general objective to provide an improved inflatable bladder hand orthosis.
It is a particular objective to provide an inflatable bladder hand orthosis useful for human subjects having spasticity and/or contractures following a neurological disease or CVA.
These and other objectives are met by embodiments disclosed herein.
An aspect of the embodiments relates to an inflatable bladder hand orthosis comprising a splint, an inflatable bladder and a bladder support. The splint comprises a palmar splint section adapted to be aligned with at least a portion of a palm of a hand of a human subject and a wrist and forearm splint section integral with or connected to the palmar splint section. The wrist and forearm splint section extends from the palmar splint section to a distance corresponding to at least a portion of a forearm of the human subject. The inflatable bladder is adapted to be aligned with metacarpophalangeal (MCP) joints of the fingers of the hand and is inflatable by introduction of a fluid within an interior chamber of the inflatable bladder. The bladder support is pivotally connected to the palmar splint section and comprises a bladder connecting surface opposite to a surface of the bladder support facing the palmar splint section. The inflatable bladder is arranged on the bladder connecting surface.
The inflatable bladder hand orthosis is, in particular, suitable for human subjects with ulnar or radial deviation. The inflatable bladder hand orthosis provides a dynamic extension of the flexor tendons on human subjects with spasticity. The inflatable bladder hand orthosis supports the MCP arch and the thumb in volar abduction, thereby providing a dynamic extension that assists in reducing tonus and strive to place the hand in a reflex inhibitory position.
The embodiments, together with further objects and advantages thereof, may best be understood by making reference to the following description taken together with the accompanying drawings, in which:
Throughout the drawings, the same reference numbers are used for similar or corresponding elements.
The present embodiments generally relate to hand orthoses, sometimes referred to as wrist-hand-finger orthoses (WHFO) or wrist-hand orthoses within the technical field. In particular, the present embodiments relate to inflatable bladder hand orthoses that are particular useful for human subjects having spasticity and/or contractures in the wrist, hand and/or digits. Such medical conditions, i.e., spasticity and/or contractures, may occur in subjects having suffered from a neurological disease or cerebrovascular accident (CVA), also referred to as cerebrovascular insult (CVI) or simply stroke.
For instance, CVA victims may suffer from a spastic pattern generally referred to as flexion pattern with anteriorly rotated shoulder, i.e., shoulder subluxation, flexed elbow joint, flexed wrist and bent fingers.
An inflatable bladder hand orthosis of the embodiments may be beneficial to such subjects by preventing or reducing spasticity, achieving tonus reduction and preventing or reducing shortening of the flexor tendon to increase the passive range of motion and stretch the contracture.
The inflatable hand splints as disclosed in U.S. Pat. Nos. 5,020,515 and 5,056,504 may be useful for stroke victims and other subjects suffering from hand paralysis to unbend severely contorted fingers. However, several such subjects may in addition suffer from radial deviation, or more commonly ulnar deviation of the metacarpophalangeal (MCP) joints. Such ulnar deviation, also referred to as ulnar drift, is caused by shortening of the flexor tendons, especially the 4thand 5th flexor tendons. This causes the fingers and the middle hand to drift towards the ulnar side, i.e., the little finger side. Radial deviation, also referred to as radial drift, correspondingly causes the fingers and the middle hand to drift towards the radial side.
The ulnar or radial drift may in fact cause the air bladder of the inflatable hand splints in U.S. Pat. Nos. 5,020,515 and 5,056,504 to come loose from the hard plastic or the wrist element, respectively. Hence, such prior art inflatable hand splints have shortcomings, in particular with regard to human subjects suffering from ulnar or radial deviation.
An aspect of the embodiments relates to an inflatable bladder hand orthosis. The inflatable bladder hand orthosis comprises a splint, an inflatable bladder and a bladder support. The splint comprises a palmar splint section adapted to be aligned with at least a portion of a palm of a hand of a human subject. The splint also comprises a wrist and forearm splint section integral with or connected to the palmar splint section. The wrist and forearm splint section extends from the palmar splint section to a distance corresponding to at least a portion of a forearm of the human subject. The inflatable bladder of the inflatable bladder hand orthosis is adapted to be aligned with MCP joints of the fingers of the hand. The inflatable bladder is inflatable by introduction of a fluid within an interior chamber of the inflatable bladder. The bladder support is pivotally connected to the palmar splint section and comprises a bladder connecting surface opposite to a surface of the bladder support facing the palmar splint section. The inflatable bladder is then arranged on the bladder connecting surface of the bladder support.
Hence, the inflatable bladder hand orthosis comprises a pivotal bladder support that interconnects the inflatable bladder to the splint. This means that the bladder support, and thereby the inflatable bladder, is pivotal relative to the palmar splint section and the splint. This pivotal arrangement of the inflatable bladder relative to the splint by means of the pivotally connected bladder support implies that the inflatable bladder hand orthosis can compensate for any ulnar or radial deviation with a significantly reduced risk of the inflatable bladder coming loose.
A further significant advantage of having the inflatable bladder pivotally connected to the splint by means of the bladder support is that is possible to optimize and adjust the position of the inflatable bladder relative to the hand of the particular subject. In particular, the inflatable bladder can accurately be adjusted not only along a distal-to-proximal axis but also pivotally adjusted to be positioned aligned with the MCP joints of the hand even if the fingers and the middle hand are drifted towards the ulnar or radial side. Such a pivotal adjustment of the inflatable bladder relative to the splint is not possible in the prior art inflatable hand orthoses, such as represented by U.S. Pat. Nos. 5,020,515 and 5,056,504.
Various embodiments of the inflatable bladder hand orthosis will now be further described with reference to the drawings.
The splint 110 comprises the palmar splint section 111 adapted to be aligned with at least a portion of the palm of the hand of a human subject. The splint 110 also comprises the wrist and forearm splint section 112. This wrist and forearm splint section 112 may be integral with the palmar splint section 111 as shown in the figures. In such an embodiment, the splint 110 is an integral piece comprising the palmar and wrist and forearm splint sections 111, 112.
In another embodiment, the wrist and forearm splint section 112 is connected to the palmar splint section 111. In such an embodiment, these two splint sections 111, 112 are two separate pieces that are connected or attached to each other.
The wrist and forearm splint section 112 comprises, in the illustrated embodiment, a forearm portion 112B to be aligned with human subject's forearm and a wrist portion 112A interconnecting the forearm portion 112B and the palmar splint section 111.
In an embodiment, the wrist portion 112A not only interconnects the forearm portion 112B of the wrist and forearm splint section 112 and the palmar splint section 111 but is preferably deformable in at least a portion adapted to be aligned with the wrist joint of the human subject's hand. In such a case, the angle between the forearm portion 112B and the palmar splint section 111 can be adapted to a suitable angle of the human subject's wrist.
For instance, the wrist portion 112A may be adapted to support the wrist in 0° to 20° extension relative to the back of the hand (dorsal extension).
In other embodiments, the wrist and forearm splint section 112 is made of a rigid or at least semi-rigid material to present a 0° angle in the wrist or a pre-set, i.e., fixed, non-zero angle in the wrist. In such a case, there is no need for any deformable materials of the splint 110, of the wrist and forearm splint section 112 or at least of the wrist portion 112A of the wrist and forearm splint section 112.
The palmar splint section 111 is, as mentioned above, designed to be aligned with at least a portion of the palm of the human subject's hand. Accordingly, the size and form of this palmar splint section 111 is preferably selected to be able to fit at least a portion of the palm.
The wrist and forearm splint section 112 can have any general form or size as long as it is capable of extending from the palmar splint section 111 along a distal-to-proximal axis 2 to a distance corresponding to at least a portion of the human subject's forearm.
For instance, the splint 110 can be manufactured in the form of a shaped sheet of, for instance, a plastic or metal material. A further variant is a palmar splint section 111 in the form of a shaped sheet and with the wrist and forearm splint section 112 in the form of a wire-based open frame structure. The wrist and forearm splint section 112 could then be constructed as a wire, for instance a plastic or metal wire, extending longitudinally, i.e., along the distal-to-proximal axis 2, and then turning back to form an open frame structure or loop. The wire preferably extends back to the palmar splint section 111, where the two ends of the wire are attached to the palmar splint section 111. In such a case, the longitudinal portions of the wire extending substantially along the distal-to-proximal axis 2 will run along a portion of the length of the human subject's forearm. Correspondingly, the transversal portions extending substantially along or angled (diagonally) relative to a radial-to-ulnar axis 1 (see
In
In an embodiment, the bladder support 130 is pivotal relative to the palmar splint section 111 around the pivotal point 3 between a radial end pivotal position and an ulnar end pivotal position.
In this embodiment, the bladder support 130 can thereby pivot or rotate relative to the palmar splint section 111 clock-wise or counter clock-wise around the pivotal point 3 to a respective end pivotal position, i.e., the radial end pivotal position and the ulnar end pivotal position.
This embodiment is described in more detail with reference to
In the above described embodiment, the pivotal or rotation limitation is achieved by means of at least one screw 140, 141 running in a respective slot 113, 115 in the palmar splint section 111 and attached or anchored in the bladder support 130 via a respective threaded blind hole 133, 135. This in turn implies that the bladder support 130 can be pivoted or rotated relative to the palmar splint section 111 and the splint 110 around the pivotal point 3 between end pivotal positions in which the shank of the screw 140, 141 engages either end 114, 117; 116, 118 of the slot 113, 115. The length of the slot 113, 115 in the palmar splint section 111 thereby dictates or restricts how far the bladder support 130 can be pivoted or rotated around the pivotal point 3. Thus, the slot length defines the maximum pivotal or rotation angle of the bladder support 130 around the pivotal point 3 and relative to the palmar splint section 111.
In an embodiment, the palmar splint section 111 comprises a single slot 113 and the bladder support 130 comprises a single matching threaded blind hole 133. In such a case, the slot 113 could be arranged on either the radial or ulnar side along the radial-to-ulnar axis 1 and relative to the pivotal point 3, and thereby relative to the distal-to-proximal axis 2.
In another embodiment, two slots 113, 115, two threaded blind holes 133, 135 and two screws 140, 141 are used as shown in
In this embodiment, a first end 114 of the first slot 113 is adapted to engage a shank of the first screw 140 and a first end 118 of the second slot 115 is adapted to engage a shank of the second screw 141 when the bladder support 130 is in the radial end pivotal position relative to the palmar splint section 111. Correspondingly, a second, opposite end 117 of the first slot 113 is adapted to engage the shank of the first screw 140 and a second, opposite end 116 of the second slot 115 is adapted to engage the shank of the second screw 141 when the bladder support 130 is in the ulnar end pivotal position relative to the palmar splint section 111.
In an embodiment, the one or two screws 140, 141 are merely used to restrict and define, when engaging either end 114, 117; 116, 118 of the one or two slots 113, 115, the radial and ulnar end pivotal positions of the bladder support 130 relative to the palmar splint section 111. In such an embodiment, the bladder support 130 may freely, i.e., without any or merely limited resistance or friction, pivot or rotate around the pivotal point 3. In such an embodiment, the length of the shank(s) of the screw(s) 140, 141 is(are) preferably slightly longer than the depth of the threaded blind hole(s) 133, 135 plus the thickness of the palmar splint section 111. Hence, there is preferably a small distance or gap between the underside of the head(s) of the screw(s) 140, 141 and the second main surface 102 of the palmar splint section 111 when the screw(s) 140, 141 is(are) screwed to the bottom of the threaded blind hole(s) 133, 135.
In another embodiment, the screw(s) 140, 141 can be used to tighten or reversibly lock the bladder support 130 to the palmar splint section 111. In this embodiment, the length of shank(s) of the screw(s) 140, 141 is(are) preferably equal to or slightly shorter than the depth of the threaded blind hole(s) 133, 135 plus the thickness of the palmar splint section 111. Tightening the screw(s) 140, 141 thereby brings the surface 132 of the bladder support 130 facing the palmar splint section 111 and the first main surface 101 (see
As a consequence, the pivotal position of the bladder support 130 relative to the palmar splint section 111 and the splint 110 can be reversibly locked by screwing the screw(s) tight into the threaded blind hole(s) 133, 135. This means that the bladder support 130 and thereby the inflatable bladder supported by the bladder support 130 can be set to a desired pivotal position adapted to the human subject's hand and MCP joints to thereby adjust to any ulnar or radial deviation.
It may be preferred that this reversible locking by bringing the surfaces 132, 101 tight together can be released or overcome if the human subject's hand suddenly should drift towards the radial or ulnar side. In such a case, the bladder support 130 is thereby released from its pivotal lock to the palmar splint section 111 rather than causing the inflatable bladder 120 to come loose from the bladder support 130.
In an embodiment and as best shown in
This sliding sheet 150 may thereby be arranged intermediate the bladder support 130 and the palmar splint section 111 to reduce any friction therebetween, i.e., between the surface 132 of the bladder support 130 and the first main surface 101 of the palmar splint section 111.
Such a sliding sheet 150 is also compatible with the above described embodiment using the screw(s) 140, 141 to reversibly lock bladder support 130 in a selected pivotal position relative the palmar splint section 111.
The sliding sheet 150 may be made of any material that would reduce the friction between the bladder support 130 and the palmar splint section 111. Non-limiting examples of such materials include polytetrafluoroethylene (PTFE), such as TEFLON®, polyethylene and polypropylene.
In an embodiment, the palmar splint section 111 comprises a through hole 119 extending through a thickness of the palmar splint section 111. The bladder support 130 then comprises a threaded blind hole 139 aligned with the through hole 119. The inflatable bladder hand orthosis 100 comprises a screw 142 passing through the through hole 119 and entering the threaded blind hole 139 to pivotally connect the bladder support 130 to the palmar splint section 111.
Hence, in this embodiment the pivotal connection between the bladder support 130 and the palmar splint section 111 is achieved by a screw 142, a though hole 119 and a threaded blind hole 139. The pivotal point 3 previously mentioned herein thereby corresponds to the position of the through hole 119 (and of the screw 142 and the threaded blind hole 139).
Other technologies of pivotally connecting the bladder support 130 to the palmar splint section 111 could alternatively be used and the invention is not limited to the above described embodiment.
In
The inflatable bladder 120 is inflatable by introduction of a fluid within an interior chamber of the inflatable bladder 120. The fluid could, for instance, be a gas, including a gas mixture, or a liquid. The fluid is preferably air. In a deflated state, the inflatable bladder 120 is positioned substantially flat on the bladder connecting surface 131 of the bladder support 130. However, once the fluid, such as air, is being introduced, typically pumped, into the interior chamber of the inflatable bladder 120, the inflatable bladder 120 starts to expand and extend from the surface 131.
Various means for attaching the inflatable bladder 120 to the bladder connecting surface 131 of the bladder support 130 are possible, for instance gluing, welding, etc. depending on the particular materials of the inflatable bladder 120 and the bladder support 130.
The introduction of fluid into the interior chamber of the inflatable bladder 120 causes an upper or dorsal portion of the inflatable bladder 120 to rise from the bladder support surface 131, while the lower or palmar portion of the inflatable bladder 120 is preferably still attached to the bladder support surface 131.
The palmar splint section 111 of the inflatable bladder hand orthosis 100 and its attached or connected inflatable bladder 120 will, by inflating the inflatable bladder 120, provide an individually adjustable support to the MCP joints and fingers of the human subject's hand together with support of the wrist on the wrist and forearm splint section 112. A pump is connectable to the valve 121 of the inflatable bladder 120 to introduce fluid, such as air, into the inflatable bladder 120 to a suitable level depending on the human subject's needs and medical condition. The level of inflation of the inflatable bladder 120 can be adjusted gradually to follow the progress of the human subject. The inflatable bladder 120 can thereby be used to open up the hand and to provide pressure absorption and finger extension.
In this way, the inflatable bladder hand orthosis 100 can be used for reduction of spasticity and/or to prevent or stretch contractures in the fingers and wrist, such after a neurological disease or CVA.
The valve 121 is opened when a pump is connected to the valve 121 and presses fluid, such as air, into the interior chamber of the inflatable bladder 120. Correspondingly, when the fluid flow into the interior chamber stops the valve 121 preferably closes to thereby prevent fluid from escaping from the inflatable bladder 120. In a particular embodiment, the pump or another equipment can also be used to deflate the inflatable bladder 120 by sucking or draining fluid out from the inflatable bladder 120 through the valve 121.
In a simpler embodiment, a plug is inserted into an opening into the interior chamber of the inflatable bladder 120 following inflating the inflatable bladder 120 by the pump to prevent the fluid from escaping. When the inflatable bladder 120 is to be deflated, the plug is simply removed allowing fluid to escape from the inflatable bladder 120. This embodiment provides an easier construction relaxing the need for a valve 121. However, it generally leads to less control of the inflation level of the inflatable bladder 120.
The inflatable bladder 120 as shown in
The designs of the inflatable bladder 120 as shown in
The inflatable bladder hand orthosis 100 of the embodiments provides a dynamic extension of the flexor tendons on human subjects with spasticity. The support of the MCP arch and the thumb in volar abduction provides a dynamic extension, which assists in reducing tonus and striving to place the hand in a reflex inhibitory position (RIP).
The splint 110 of the inflatable bladder hand orthosis 100 is preferably manufactured from a metal material, including a metal alloy material. Suitable, but non-limiting, examples of such metal (alloy) materials include iron alloys, aluminum and aluminum alloys, e.g., malleable aluminum or aluminum alloys.
The metal material of the splint 110 is preferably deformable at least in the wrist portion 112A of the wrist and forearm splint section 112. Hence, the metal material is preferably not brittle and can be bent slightly to form a bend at the wrist portion 112A that are adapted to the particular human subject.
Although metal materials may be suitable for manufacturing the splint 110 other materials could alternatively be used, such as plastics and in particular low temperature thermoplastics, e.g., such low temperature thermoplastics that are heated in hot water at, for instance, 75 to 85° C. or using at heat gun.
The bladder support 130 of the inflatable bladder hand orthosis 100 may be manufactured from metal or plastic materials similar to the splint 110.
In an optional embodiment, the first main surface 101 of the splint 110 facing the wrist and forearm of the patient and/or the second, opposite main surface 102 of the splint 110 may be coated with or comprise a pressure reducing coating, layer or laminate. Such a pressure reducing coating, layer or laminate will increase the comfort for the patient wearing the inflatable bladder hand orthosis 100. If both main surfaces 101, 102 of the splint 110 comprise a respective pressure reducing coating, layer or laminate, a sandwich structure is obtained.
Any pressure reducing materials known in the art and that can be coated onto or otherwise applied to the splint 110 could be used according to the embodiments. Non-limiting examples include polychloroprene materials, such as NEOPRENE®. In particular, NEOPRENE® coatings, layers or laminates with closed cells could be used as pressure reducing material.
The inflatable bladder hand orthosis 100 may comprises a textile dress 160, also referred as cloth dress, see
The textile dress 160, thus, has dual functions for the inflatable bladder hand orthosis 100. Firstly, it secures the inflatable bladder hand orthosis 100 to the hand and forearm of the human subject using the closing straps or bands 161, 162, 163 that are wrapped around the hand and the forearm. The closing straps 161, 162, 163 are preferably secured at the textile dress 160 by means of hook and loop fasteners, such as VELCRO® fasteners. In such a case, at least a portion of the closing straps 161, 162, 163 comprises hook or loop material as schematically shown in
Secondly, the textile dress 160 constitutes a soft surface facing the skin of the hand and forearm. The textile dress 160 could thereby provide pressure absorption to make the inflatable bladder hand orthosis 100 comfortable to wear.
Various textile materials can be used, including filled textile materials.
In an alternative embodiment, the multiple closing straps are attached directly to the splint. For instance, at least one closing strap can be arranged connected to the palmar splint section and at least one closing strap is arranged connected to the wrist and forearm splint section.
The embodiments described above are to be understood as a few illustrative examples of the present invention. It will be understood by those skilled in the art that various modifications, combinations and changes may be made to the embodiments without departing from the scope of the present invention. In particular, different part solutions in the different embodiments can be combined in other configurations, where technically possible. The scope of the present invention is, however, defined by the appended claims.
Number | Date | Country | Kind |
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16179287.4 | Jul 2016 | EP | regional |