Abstract:
A therapeutic ankle and foot apparatus having a contact sensor mechanism. The sensor mechanism comprising a contact switch disposed between an ankle and foot apparatus and the heel of a patient&#39;s foot. The contact sensor mechanism determines any proximal contact with the patient&#39;s heel and communicates with an activation indicator that contact is present. The activation indicator may be visual and/or audible, and it may be positioned on the apparatus or at a remote location, communicating by wire or wireless telecommunication linkage.

Description:
BACKGROUND OF THE INVENTION 
     1. Technical Field 
     This invention relates to orthotic and prosthetics that have sensor devices used to continuously monitor the amount of pressure on soft tissue confined therein. Orthosis such as therapeutic ankle and foot brace support the patient&#39;s foot for isolated pressure relief against portions thereof. Optimal outcome for such processes are jeopardized by improper refitting of the orthotics by the patient or unskilled caregiver. 
     2. Description of Prior Art 
     Prior art devices of this type have generally been directed to pressure sensing devices that measure the effective pressure on the patient&#39;s foot with the supporting surfaces. Typically, such pressure sensing devices are integrated within the footwear such as shoes as seen in U.S. Pat. Nos. 4,647,918, 5,566,479, 5,642,096 and 5,678,448. 
     In U.S. Pat. No. 4,647,918 a multiple event pressure notification system is disclosed wherein multiple pressure monitoring points are arranged within the footwear and interconnected to a microprocessor programmed to detect varying pressure amounts and calculate same to time and locale. An alarm sounds when pressure exceeds a pre-programmed threshold at any one of the given pressure indicating points. 
     U.S. Pat. No. 5,566,479 discloses a shoe for diabetics or others having four sensor resistors that activate an alarm circuit when a pre-selected threshold pressure amounts are reached. 
     U.S. Pat. No. 5,642,096 uses a series of pizorisistois sensors arranged in arrayed pairs within the inner sole of the footwear in pressure increase and decrease arrays. The system measures both pressure and temperature through which the patient&#39;s foot is exposed. 
     U.S. Pat. No. 5,678,448 defines a self-contained system to measure forces that are applied to the foot within the shoe by a matrix of four sensors covering the inner sole of the shoe. 
     Additional prior art is directed to pressure sensing systems to measure increasing pressure between the injured portion of a patient&#39;s body and confinement, see, for example, U.S. Pat. No. 4,858,620 having a plurality of pressure sensors within an orthopedic restraining member that indicates once a critical pressure value is reached an alarm activation. 
     U.S. Pat. No. 5,790,256 is directed to a foot analyzer that uses both pressure sensing and optical sensors to analyze a patient&#39;s foot placed within the sensing enclosure. 
     Finally, U.S. Pat. No. 5,838,214 refers to an interface pressure measurement device that interfaces between a patient&#39;s foot and surrounding support surfaces. The device has two sensor sheets of thin flexible plastic material arranged so that when the sheets touch an electrical contact is presented forming a sensing switch. 
     SUMMARY OF THE INVENTION 
     A therapeutic ankle and foot apparatus having a contact sensor indicator whereby any physical pressure on the isolated portion of the patient&#39;s foot will be detected and indicated by an auditory and visual activation alarm circuit. The contact sensor can be one of a variety of pressure or proximal activation switching elements positioned between the patient&#39;s foot and the therapeutic ankle and foot apparatus. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side elevational view of the therapeutic ankle and foot brace with the contact sensor indicator positioned therein; 
     FIG. 2 is an enlarged partial side elevational view of the heel spacing portion of the brace illustrating switching elements of the invention positioned therein; 
     FIG. 3 is a partial front elevational view of a heel and leg support element of the brace with the switching elements of the invention secured thereto. 
     FIG. 4 is an enlarged partial cross-sectional view of the contact switch strip chosen for illustration representation; 
     FIG. 5 is enlarged partial top plan view of the contact switch strip as seen in FIG. 4 with portions broken away; 
     FIG. 6 is an illustrated side elevational view of an alternate form of the invention; 
     FIG. 7 is an illustrative circuit diagram of an alarm activation circuit associated with the invention; 
     FIG. 8 is a front elevational view of an alternate form of the invention illustrating a sensor circuit of the invention on a leg brace; 
     FIG. 9 is a front elevational view of a second alternate form of the invention illustrating an anterior hyper-extension brace with contact sensors positioned within; and 
     FIG. 10 is a front elevational view of a third alternate form of the invention illustrating a sensor circuit on a body jacket brace. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     A contact sensor mechanism  10  can be seen in FIGS. 1-5 of the drawings to detect any contact of a patient&#39;s heel  11  within an ankle and foot apparatus  12 . The contact sensor mechanism  10  has a contact switch  13  and interconnected by wires  13 A to an activation indicator  14 . 
     The ankle and foot apparatus  12 , best seen in FIG. 1 of the drawings, has a leg portion  15  and a foot portion  16  and a heel portion  17 . The foot portion  16  is at an angle to the leg portion  15  interconnected by the heel portion  17 . The foot portion  16  has a footpad  18  connected to an attachment base  19 . A resilient walking pad  20  is secured to the attachment base  19 . A pair of longitudinally spaced aperture tabs extend from the respective side edges  22  of the footpad  18 . A toe support extension member  23  adjustably extends from the foot portion  16 . The toe support extension member  23  has a generally flat base area  24  with an angularly offset end portion  25  with a resilient pad  25 A secured thereto. The toe support extension member  23  is adjustably positioned between the footpad  18  and the attachment base  19  by a pair of fasteners F. The fasteners F extend through the apertures in the attachment base  19  and the resilient walking pad  20  via registration slots S shown in broken lines within the flat base area  24 . The fasteners F are threadably secured into the respective fittings F 1  within the footpad. It will be seen that the heel portion  17  extends from a mounting pocket  26  formed within the bottom of the footpad  18 . The heel portion  17  is secured within the mounting pocket  26  by a pair of threaded fasteners F extending through respective apertures in the resilient walking pad  20  and attachment base  19  and are threadably secured into a fitting F 3  in the footpad  18 . 
     The heel portion  17  is transversely flat and longitudinally contoured extending from the foot portion  16  to and engageable within the leg portion  15  so as to provide a space between the patient&#39;s heel  11  and the heel portion  17 . 
     The leg portion  15  has an enlarged transversely contoured leg support member  27  with a recessed channel  28  within. The heel portion  17  is secured within the recesses channel  28  by fasteners F as will be well understood by those skilled in the art. 
     By referring to FIGS. 1-3 of the drawings, the contact sensor mechanism  10  can be seen having a contact switch  13 , secured to an inner surface  17 A of the heel portion  17  facing the patient&#39;s heel  11 . Lead wires  13 A extend from the contact switch  13  along the leg support member  27  and are interconnected to the activation indicator  14 . In this embodiment, the activation indicator  14  is positioned on the leg engagement strap  29  that is adjustably secured to the leg support member  27  by buckles  30  as best shown in FIG. 1 of the drawings. It will be apparent to those knowledgeable within the art that different mounting positions for the activation indicator  14  can be utilized and it is a matter of choice as to the exact positioning of the activation indicator  14 . 
     Referring to FIGS. 3-5 and  7  of the drawings, the contact switch  13  can be seen having a generally flat rectangular base member  31  with a plurality of longitudinally spaced annular recessed areas  32  therein. The rectangular base member  31  is preferably made of a non-conductive synthetic material. Each of the recess areas  32  has a contact wire  33  extending thereacross which are in communication with lead wires  33 A which in turn communicate with one another forming one side of an electrical contact circuit. A resilient conductive thin metal mask  34  is bonded to a thin non-conductive carrier strip  35  and overlies the rectangular base  31 . The conductive mask  34  defines multiple registration activation disks areas  34 A aligned over the respective recess areas  32  in spaced relation thereto so as to form multiple deflectable contact switches  35 A. Such contact switches are commercially referred to as ribbon or membrane activators for large area coverage and are available from a variety of commercial sources. It will be evident from the description above that other commercially available electrical switches of this type can be substituted having a low activation force and with a low to moderate height profile. An example of a preferred switch activation force requirement would be in the range of 50 to 100 grams of impingement force to deflect a switch portion providing a contact and activation of the same. 
     It will be evident that the positioning of the contact switch  13 , in this preferred embodiment on the heel portion  17  is critical to its effectiveness so that any contact of the patient&#39;s heel  11  or adjacent heel area  11 A with the foot and ankle apparatus  12  can be detected so that the same can be readjusted to fit properly. The contact switch  13  therefore will be preferably positioned based on its physical characteristics and chosen method of mounting which in this example is an adhesive band  36  on the rectangular base  31 , as seen in FIG. 4 of the drawings. 
     A proximal switch  13 B is also illustrated in FIGS. 1,  2  and  3  of the drawings wherein a secondary switching device is used in conjunction with the primary contact switch  13  to afford additional warning of engagement by the patient&#39;s foot with the ankle and foot apparatus  12 . The proximal switch  13 B is also interconnected to the activation indicator  14  via the wires  13 A. 
     Referring to FIG. 7 of the drawings, a system circuit  37  of the activation indicator  14  can be seen illustrated within the broken lines. The system circuit  37  comprises a source of power  38  (battery), an audible output device  39  and a visual warning light  40  and the contact switch  13 . When the contact switch  13  is activated the circuit is completed which activates the visual and auditory circuit elements. It will be evident that either the warning light  40  or audible output device  39  can be used in accordance with the preference of the user&#39;s environment as will be well understood by those skilled in the art. 
     Referring again to FIG. 1 of the drawings, a fabric foot engagement enclosure  41  is shown having a durable mounting base portion  42  securing a fabric sleeve  43  that is lined with a soft synthetic fur-like material  44 . The durable mounting base  42  provides a reinforcement contoured mounting surface from which a plurality of fastening straps  45  removably secure the foot engagement enclosure  41  to the foot pad  18 . The straps  45  extend through the apertured tabs  21  holding the same in position thereagainst. 
     The fabric sleeve  43  and durable mounting base  42  define a cutout heel portion  46  for the patient&#39;s heel  11 . Secondary straps  47  extend from the fabric sleeve  43  and the durable mounting base  42  for registered engagement through respective buckles  47 ′ to secure the foot portion  16  about a patient&#39;s foot  48 . Releaseably securing hook material HM and loop material LM, collectively referred to as releasable securing materials are used on the fastening straps  45  and secondary straps  47  for self-engagement through the respective buckles  47 ′ and apertured tabs  21 , securing the durable mounting base portion  42  to the base  18 . 
     In use, the patient&#39;s foot  48  is positioned within the fabric foot engagement enclosure  16  and secondary straps  47  are secured through the respective buckles  47 ′. A pair of heel tabs  49  formed from the hereinbefore disclosed mounting base  42  and fabric sleeve  41  are secured in overlapping relationship over the patient&#39;s heel  11  by straps  50  which are the same releasable securing material LM and HM. 
     Referring now to FIG. 6 of the drawings, an alternate form of the invention is illustrated wherein a contact switch  13 ′ is positioned on a heel portion  17 ′ of an ankle and foot apparatus  12 ′. A self-contained wireless transmitter  51  is secured to the outer surface  52  of the heel portion  17 ′ and in communication with the contact switch  13 ′. A remotely located alarm module  14 ′ has a wireless receiver  53  therein for receiving an output signal  50 ′ from the wireless transmitter  51  when it is activated through the patient&#39;s foot or heel contacting the switch  13 ′ as hereinbefore described. 
     It will be evident from the above referred to description that should the patient&#39;s heel  11  or adjacent foot area contact the contact switches  13 ,  13 ′ or  13 B that the activation indicator  14  or  14 ′ will activate indicating that adjustment needs to be made with the orthotic brace  12  or  12 ′ to alleviate engagement pressure and possible tissue breakdown of the patient&#39;s affected area. 
     Referring to FIG. 8 of the drawings, an alternate form of the invention can be seen wherein a leg brace  60  is illustrated having a knee joint portion  61  and an ankle joint portion  62  as will be well understood by those skilled in the art. The knee joint portion  61  of the leg brace  60  has a contact switch strip  63  as hereinbefore described (as contact switch  13 ) being secured adhesively to the inner side surface  64  of a joint brace armature  65 . 
     An alarm activation indicator module  66  positioned on an upper portion  67  of the leg brace  60  and is interconnected by wires  66 A to the respective contact switch strips  63 . The alarm activation indicator  66  is identical to that of the activation indicator  14  as set forth in the preferred embodiment above. 
     Referring now to the ankle joint portion  62  of the leg brace  60 , a sensor contact switch strip  68  is adhesively secured to an inner surface  69  of the ankle joint portion  62  and is interconnected to a remote alarm activation indicator  70  by quick release leads  71  (well known and understood by those skilled in the art). 
     Both the contact switch strip  63  and  68  respectively are positioned on brace areas that are required to maintain an air contact gap between the brace elements and a portion of the patient&#39;s leg  72 . 
     Referring now to FIG. 9 of the drawings, an anterior hyper-extension body brace  73  can be seen having a sternum pad  74  and a pubic engagement brace pad  75 , each with engaging arm pairs  74 A &amp;  74 B and  75 A &amp;  75 B extending therefrom and being interconnected by a pair of metalized brace elements  76 A &amp;  76 B as is typical within the art. In many applications due to the impaired sensor perception of a disabled patient  77  it is important to maintain proper positioning of the brace  73  which given the human physiology will move during transition from a sitting position to a standing or laying position. 
     In order to detect such movement, a contact sensor switch  78  is positioned on the top edge  79  of the sternum pad  74  with a self-contained alarm activation indication module  80  interconnected by wires  80 A. 
     Conversely, the pubic brace pad  75  has a contact sensor switch  81  as hereinbefore described positioned on its bottom perimeter edge  82  interconnected to the alarm activation indication module  80  by wires  80 B. It will be evident that upon relative movement of the sternum pad or pubic pad in relation to the patient, the contact switch will activate the alarm activation module indicator alerting the patient and/or caregivers to the inappropriate positioning of the brace. 
     Referring now to FIG. 10 of the drawings, a modified therapeutic body jacket brace  81  can be seen which is used for therapeutic support and immobilization, again which is well known and typical within the art. 
     A plurality of thin contact sensor pads  82  indicated by shaded areas are integrally positioned on the inner surface of the body jacket brace  81  in specified non-contact areas. An alarm activation module indicator  83  is interconnected to the multiple contact sensor pads  82  by wired as indicated by dotted lines at  84 . It will be evident that the alarm activation indicator module  82  is identical to the hereinbefore-described activation indicator  14  of the preferred embodiment and defines the system circuit  37  as noted above. Such system circuits  37  can be easily modified by those skilled in the art to support individual sensor activation indicators so that specific sensor activation can be determined as well as integrated sensor connection which any of the sensors will activate the central alarm activation indicator modules  82  upon contact. 
     Both the alternate contact sensor mechanisms illustrated and described in FIGS. 9 and 10 of the drawings can also be formatted as remote alarm activation indicator modules wherein the respective alarm activation indication modules  77  and  82  are remotely positioned from the respective braces  71  and  80  for ease of the caregiver to monitor bedside. 
     It will thus be seen that a new and novel contact indicator for the therapeutic foot and ankle apparatus  12  has been illustrated and described and that various changes and modifications may be made therein without departing from the spirit and scope of the invention.