Abstract:
A simplified prosthetic device and methods of use thereof is disclosed with splinting means; an elongate static arm fixedly attached to said splinting means; an elongate mobile arm with a first end and second end, said mobile arm being flexibly attached at said first end to said static arm; an elastic element for allowing re-extension of said mobile arm and attached to said mobile arm and an anchor point; means for translating gross body movements to the mobile arm; and an attachment being attached to the second end of the mobile arm.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to U.S. Provisional Application 61/139,577, filed on Dec. 20, 2008, the entirety of which being incorporate herein by this reference. 
     
    
     RIGHTS 
       [0002]    This invention was made with support from the United States Government, specifically, the United States Army Institute of Surgical Research, and accordingly, the United States has certain rights in this invention. 
     
    
     FIELD AND BACKGROUND OF THE INVENTION 
       [0003]    The present invention relates generally to prosthetic and orthotic devices, and specifically to a simplified, harness-free, body-powered, upper-extremity prosthesis. 
         [0004]    A body-powered prosthesis is powered and controlled by gross body movements. Patients are able to capture the movements of their shoulder, upper arm or chest by a harness system, which is attached to a cable that is connected to a terminal device (hook or hand). An elbow system can be added to provide the patient additional functionality. For a good over-view of progressive upper limb prosthetics see (Lake C, 2006) 
         [0005]    Because of its simple design, this type of prosthesis is highly durable and easy to maintain. However, wearers typically complain that these systems are uncomfortable due to the restrictive harness. Therefore, a more comfortable body-powered prosthetic device is needed that retains a simple design. 
         [0006]    Another disadvantage of known body-powered prostheses is that the particular disability of a patient may disqualify him or her from being able to use the device properly. 
         [0007]    To be a candidate for known body-powered prostheses, a patient must possess at least one or more of the following gross body movements: glenohumeral flexion, scapular abduction or adduction, shoulder depression and elevation, and chest expansion. Additionally, a patient must have sufficient range of motion, musculature and residual limb strength to successfully manipulate the prosthesis. Therefore, there exists a need for a body-powered prosthesis that reduces the need for multiple gross body movements and range of motion to function properly. 
         [0008]    Frequently, patients with severe burns or tissue trauma to their remaining limbs are not able to receive a prosthetic device until they are fully healed. This could take months, forestalling the physical therapy and training necessary for a patient to regain function and independence. Therefore, a need exists for a simple prosthesis that may be comfortably worn by a recently injured patient and which requires minimal gross body movement or range of motion to function properly. 
         [0009]    The needs noted above are presently unmet by upper-extremity prosthesis known in the art. 
         [0010]    U.S. Pat. No. 1,989,960 to Wheeler et al. shows a complicated, body-powered, prosthesis requiring a plurality of beveled, pivoting, co-acting joint sections and a shoulder harness for mounting the device on the user. 
         [0011]    The prosthetic arm in U.S. Pat. No. 2,834,024 to Aveni requires a supporting harness, hollow arm sections, and a pulley. 
         [0012]    U.S. Pat. No. 1,366,453 to Henning features a device that also requires a shoulder harness, and a saddle adapted to rest upon the user&#39;s shoulder. 
         [0013]    Fishbein et al., in U.S. Pat. No. 2,537,338, disclose a prosthetic arm with a complex elbow assembly requiring rotatable cam members with engaging teeth and a harness adapted to be secured on the shoulders of the wearer. 
         [0014]    The lateral thumb hand prosthesis disclosed in U.S. Pat. No. 4,258,411 to Bell requires a prosthetic hand and lateral thumb connected to a harness on the shoulder opposite the side of the amputation by way of the posterior elbow. 
         [0015]    It is, therefore an object of this invention to provide a simple, comfortable, harness-free, body-powered upper extremity prosthesis capable of being worn and used by patients of limited physical ability. 
       SUMMARY OF THE INVENTION 
       [0016]    The device provides the patient with an artificial elbow that may be “bent” through flexion and/or abduction of the patient&#39;s natural upper arm. The device includes a base or support that is fixed to the upper arm. The base may comprise a pair of semi-cylindrical plastic shells with hook and loop straps for attachment to the upper arm. A hinged member includes a pair of elongate arms pivotally joined together. One elongate arm is securely fixed to the base and functions as the lower portion of the patient&#39;s upper arm. The pivot on the hinged member functions as the elbow. The other elongate arm functions as the forearm. 
         [0017]    The end of the “forearm” member may be used to attach different articles that may be used by the patient, such as eating utensils, toothbrush, etc. Near the end of the “forearm” member a thread, wire or the like is attached. An eyelet is fixed to the base on the inner side, i.e., toward the chest area. The thread leads from its attachment point on the “forearm” member, through the eyelet on the base and then to a second attachment point near the patient&#39;s waist, on the same side as the device. The second attachment point may take the form of a loop for a belt to pass through, a piece of foam that may be tucked in a patient&#39;s waist line, or similar anchoring devices. When the patient flexes or abducts his/her upper arm, the “forearm” member pivots toward the patient, in the manner of an elbow. Thus, the patient is able to perform otherwise impossible tasks. 
         [0018]    The various features of novelty that characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive in which a preferred embodiment of the invention is illustrated. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]    In the drawings: 
           [0020]      FIG. 1  shows an exploded, perspective view of an embodiment of the invention with a spoon attachment. 
           [0021]      FIG. 2  shows an overhead, plan view of an embodiment of the invention with a spoon attachment. 
           [0022]      FIG. 3  shows a drawing of an embodiment of the invention with a fork attachment in use by a patient 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0023]    In  FIG. 1  the simplified prosthetic device  10  as worn on the amputee&#39;s limb  15  is shown with its constituent elements in exploded view. The limb is covered by an optional compression sleeve  17 . The device  10  is secured to the limb  15  by splinting means  20 , preferably of 1% perforated thermoplastic moulding such as that sold by Patterson Medical Holdings, inc., 270 Remington Boulevard Suite C Bolingbrook Ill. 60440 (Sammons Preston Rolyan) under the trademark POLYFORM™ splinting material. In one embodiment of the invention, the splinting means  20  is composed of two, curved, over-lapping halves ( 20   a  and  20   b ), wherein the smaller (medial/anterior) splint half  20   b  is manufactured so as to fit within the peripheral edge  25  of the larger (lateral/posterior) splint half  20   a  in an arrangement known in the art as a “clam shell” splint. The larger splint half  20   a  should overlap the smaller splint half  20   b  preferably by ½″ to 1 inch. 
         [0024]    Continuing with  FIG. 1  of the preferred embodiment of the invention, we see that the smaller splint half  20   b  and the larger splint half  20   a  are fit tightly yet comfortably over the amputee&#39;s limb  15  in the overlapping arrangement as shown and described above. The splinting means  20  is secured to the limb  15  by securing means  30 , which in the preferred embodiment are fabric hook-and-loop fastener cinch straps sold under the trade name VELCRO™ by Velcro USA Inc., 406 Brown Avenue, Manchester, N.H. 03103. The securing means  30  are affixed to the splinting means  20  by attachment means  35 , preferably speed rivets such as those manufactured by Avdel USA LLC, 614 NC Highway 200 South, Stanfield, N.C. 28163 under the product line BRIV™ SPEED FASTENING™ System. The optional use of adhesive padding, preferably a moleskin blister cover (not shown), may be used to cover the rivets  35  protruding on the inside of the splinting means  20  in order to prevent chaffing and improve the comfort of fit. The rivets  35  can be placed through the manufactured perforations of the preferred POLYFORM™ material or an awl, rotary punch or similar device may be used to prepare the securing means  30  for attachment to the splinting means  20 . 
         [0025]    Moving now to the arm  40  of the embodiment of the invention shown in  FIG. 1 , we see that it is comprised of a pair of elongate arms ( 43 , 47 ) pivotally joined at a hinge  50 . A proximal static elongate arm  43  is fixedly secured to the splinting means  20  by attachment means  35  through arm apertures  53  along the midline of the humerus of the limb  15  so that the hinge  50  extends preferably 1 to 2 inches beyond the distal end of the limb  15 . Thus, the static arm  43  functions as the lower portion of the patient&#39;s upper arm. The hinge  50  functions as the elbow. The remaining distal mobile elongate arm  47  functions as the forearm. In the preferred embodiment of the invention, the arm  40  is a well known phoenix elbow hinge, such as that sold by RehabMart, LLC, 150 Sagewood Drive, Winterville, Ga. 30683 as model no. NC-15453. 
         [0026]    Continuing the discussion of the arm  40  of the preferred embodiment of the invention, the mobile arm  47  also has manufactured apertures ( 60 ,  62 ) near the distal end of the mobile arm  47  and along its midline. A connecting means  72 , preferably 50 lb test monofilament, is attached at the distal aperture  62  of the mobile arm  47  and threaded through an eyelet  70  which is fixedly attached to the splinting means  15 . The connecting means  72  may be attached to an optional anchoring means  73 , such as a block of foam for tucking into the amputee&#39;s waistline. Alternately, the connecting means  72  may be secured directly to the amputee&#39;s clothing (not shown) as, by way of example, to a belt loop. 
         [0027]    Redirecting attention to the hinge  50  of the arm  40  shown in  FIG. 1 , we see that the hinge  50  is characterized by both an adjustable extension  80  and adjustable flexion  83  motion stop. The extension motion stop  80  is placed at an area on the hinge  50  distal to the static arm  43  (behind the mobile arm  47 ), in such a way as to prevent hyper-extension of the mobile arm  47 . The flexion motion stop  83  is placed behind and near the static arm  43  to prevent hyper-flexion during use. In order to assist with extension of the mobile arm  47 , an elastic element  90  securely connects the mobile arm  47  to the hinge  50 . In  FIG. 1 , the elastic element  90  is a rubber band wrapped around the mobile arm  47  at a first end  93  and hooked around the extension motion stop  80  at a second end  95 . 
         [0028]    A cuff  100  for receiving a sliding element  105  is fixedly attached to the distal end of the mobile arm  47  of the preferred embodiment of the invention as shown in  FIG. 1 . The sliding element  105  is manufactured to receive a utensil attachment  110  by allowing the operator (not shown) to insert an attachment means  112 , preferably a screw and wing nut, through an elongate slot  115  which allows for the variable placement of the attachment  110  along the longitudinal axis of the sliding element  105 . Using the combination of the cuff  100 , the sliding element  105 , the elongate slot  115 , and the attachment means  112 , the configuration of the prosthetic advice is infinitely adjustable to meet a variety of body types, functions and circumstances, thereby augmenting the overall utility of the device. 
         [0029]    Turning now to  FIG. 2 , we see an overhead, plan view of an embodiment of the invention  10  in use with a spoon utensil attachment  110 . By moving the patient&#39;s residual arm  15  through shoulder flexion and/or abduction, the connection means  72  translates the force of the shoulder flexion and/or abduction to its attachment point on the mobile arm  47 , causing the mobile arm  47  to pivot towards the operator (not shown) around the hinge  50 , thereby positioning the utensil attachment  110  into the desired position for functional activities. The length of the connection means  72  may be adjusted to accommodate for an increase or decrease in the range of motion of the residual limb  15 . The elastic element  90  provides the tension necessary to facilitate extension of the mobile arm  47  after the force on the connection means  72  is reduced or discontinued entirely. The motion stops ( 80 ,  83 ) can be secured in various positions to lock the hinge  50  in a particular position to facilitate the use of the device for a particular activity such as, by way of example, writing, typing, and changing television stations. The use of spoon as a utensil device  110  is only one example of a utensil attachment that may be developed for use with this invention. 
         [0030]    On  FIG. 3  we see an embodiment of the invention mounted on the left residual limb  15  of an amputee  115 . In this example, the embodiment of the invention  10  has been fitted with a fork utensil attachment  110  by attachment means  112  to the sliding element  105 . By adjusting the angle along the plane of rotation created by the intersection of the sliding element  105  and the utensil attachment  110 , the utensil attachment  110  may be adjusted as necessary to serve its intended function, in this instance, for eating. Further adjustments may be made by adjusting the attachment means  112  along the axis of the sliding element  105  using the elongate slot  115 . Yet further adjustment may be made by adjusting the sliding element  105  within the cuff  100 . The amputee  115  is using the movement of his shoulder  120  to create force along the connecting means  72  attached to his waist  128  by various means. The force of the shoulder  120  flexion and/or abduction is translated along the connecting means  72 , through the eyelet  70  to the mobile arm  47  causing is to flex along the hinge  50  towards the amputee  115 , thereby bringing the utensil attachment  110  closer to the amputee&#39;s mouth  130 . The degree of flexion and extension of the mobile arm  47  can be limited by the strategic placement of the motion stops ( 80 ,  83 ). The elastic element  90  assists in the re-extension of the mobile arm  47  to reset the prosthetic device  10  to receive more food (not shown) using the fork utensil attachment  110 . 
         [0031]    While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles. 
       REFERENCES 
       [0032]    The contents of each of which, and the contents of every other publication, including patent publications such as PCT International Patent Publications, being incorporated herein by this reference.
   Lake C, D. R. ( 2006 ). Progressive upper limb prosthetics. Phys Med Rehabil Clin N Am, 17 (1), 49-72.