Abstract:
An orthopedic device ( 10 ) is provided for the treatment of physical disorders characterized by region(s) of localized, undue compression of body tissue leading to nerve compression and/or damage, such as carpal tunnel syndrome. A carpal tunnel syndrome treatment device ( 10 ) in accordance with the invention includes a central, resilient, stretchable tensioning segment ( 12 ) with a plurality of relatively less stretchable adhesive straps ( 14-18 ) secured to the segment ( 12 ). In use, the segment ( 12 ) is placed on the back of a patient&#39;s hand ( 20 ), whereupon the straps ( 14-18 ) are pulled and adhered to the patient&#39;s palm in a fashion to expand the segment ( 12 ). In this orientation, the control segment ( 12 ) exerts continuous yielding or tensile forces through the straps ( 14-18 ) which in turn reduces carpal tunnel syndrome nerve compression and alleviates symptoms.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention is broadly concerned with improved method and apparatus for the treatment of compressive syndrome physical disorders characterized by a region of localized, undue compression of body tissue, for example, carpal tunnel syndrome. More particularly, the invention is concerned with such methods and devices wherein use is made of a central tensioning segment formed of resilient, stretchable material (e.g., synthetic elastomer or latex rubber) together with a plurality of adhesive attachment straps of limited stretchability secured to the tensioning segment for securement of the device on a person&#39;s body. The tensioning segment exerts a continuous yielding or tensile force through the straps, serving to at least partially reduce the troublesome tissue compression. 
     2. Description of the Prior Art 
     Carpal tunnel syndrome and related conditions result from repeated trauma to the tendons and soft tissue structures forming a part of the wrist. Excessive pressure on the carpal tunnel contents, including the flexor tendons, nerves and bursa, results in abnormal function, weakness, inflammation, pain, numbness and ultimately in nerve tissue injury. 
     The flexor retinaculum is a thick, relatively unyielding ligamentous band that crosses the groove on the palmer surface of the carpal bones. It is composed of the palmer (volar) carpal ligament and transverse (anterior annular) carpal ligament. The palmer carpal ligament is attached medially and laterally to the styloid processes of the radius and ulna. The transverse carpal ligament is attached medially to the pisiform bone and the hamulus of the hamate, and laterally to the tuberosity of the scaphoid and palmer surface of the ridge of the greater multangular (trapezium). The fibers of these ligaments merge at the distal end of palmer and proximal end of the transverse ligament. Together with the carpal bones and articulations, they form a tunnel through which pass the deep flexor tendons and median nerve. 
     The median nerve passes through the carpal tunnel adjacent the flexor retinaculum and between it and the flexor tendons and their bursa. The carpal tunnel is barely adequate to accommodate these structures and it is generally felt that any narrowing of the diameter of the tunnel or decrease in the diameter to contents ratio, causes injury to the median nerve by repeatedly pressing it against the relatively unyieldable retinaculum. Repetitive and/or constant forceful movement, in particular extension movements of the hand, are thought to repeatedly traumatize the median nerve in this manner, as does the repetitive and/or constant force contracture of the thenar muscles. 
     Current medical treatment of carpal tunnel syndrome consists of rest, restriction from traumatizing activities, limiting movement with restrictive splints, anti-inflammatory medication and cortisone injections. In advanced cases surgery is used to transect and spread the transverse carpal ligament to allow more room for the contents of the carpal tunnel, i.e., an increase in the diameter to contents ratio. Some form of wrist support or splint is normally used in the early stages of treatment. They are used in an attempt to delay progression of the condition or as an adjunct to some other treatment in an effort to lessen the pain and aid in the return to normal function. Subsequent to surgery, wrist splints are frequently used to support the wrist and aid in recovery. Thus it is important that a presurgical device be provided which corrects the condition or prevents further development and/or progression of the condition. 
     Given the widespread incidence of carpal tunnel syndrome and similar disorders, many attempts have been made to provide orthopedic supports or braces for the wrists which will alleviate the symptoms and/or provide a means of eliminating the problem in its entirety. For example, U.S. Pat. No. 5,921,949 describes a corrective support designed specifically for the treatment of a tunnel syndrome. However, none of these past efforts have resulted in a truly effective device or treatment for the syndrome. Therefore, the traditional treatments described previously remain the methods of choice in most cases. 
     In addition to carpal tunnel syndrome, a number of other compressive syndrome conditions have been identified. These include radial tunnel syndrome (sometimes referred to as “tennis elbow”). In this condition, the supinator muscle, while turning the wrist in the clockwise direction compresses the radial nerve. The radial nerve feeds the muscles of the back of the forearm. It is most commonly seen with twisting activities of the arm. Pain if first noticed at the lateral side of the elbow, about two inches toward the wrist from the elbow. Rest is currently the best treatment to allow swelling to go down. DeQuervain&#39;s Tenosynovitis is a problem of the abductor pollicis longus and extensor policis longus tendons which irritate the bursa coating, called tenosynovius becoming tenosynovitis when inflammation occurs. Irritation continues forming scar tissues. The present treatment protocol attempts to reduce the swelling in the area by reducing the usage. 
     Frozen shoulder is a joint dysfunction and is often caused by adherence of the anterinferior aspect of the joint capsule to the humeral head. This condition often occurs after injury, being a scar formation type dysfunction. Piriformis Syndrome is a condition where the sciatic nerve is compressed between the piriformis muscle and the gemellus muscle. 
     Guyons&#39; Canal syndrome is a common nerve compression affecting the ulnar nerve and possibly the ulnar artery as it passes through a tunnel in the wrists on the lateral portion. The problem is similar to carpal tunnel syndrome, but involves a completely different nerve. Sometimes both conditions can be causing problems in the same hand. 
     Thoracic Kyphosis is the loss of movement in the upper back area, described as a derangement syndrome and is caused by adaptive shortening, as a result from poor postural habits over a sustained period. Derangement syndrome is believed to be caused by a disturbance of some structure with the joint causing mechanical deformation of pain sensitive structures. 
     Trigger points are muscle conditions where an involved area is relatively spasm, building up lactic acid in the muscle, with resultant pain. 
     After surgery, scar tissue can ball up and contract, in unnatural orientations. This can cause severe pain to a patient. 
     While all of these types of compressive syndrome conditions have been recognized for many years, there has been no readily available, non-surgical treatment available to alleviate the symptoms thereof. 
     SUMMARY OF THE INVENTION 
     The present invention overcomes the problems outlined above and provides an improved device for the treatment of compressive syndrome disorders such as carpal tunnel syndrome, but also including radial tunnel syndrome, DeQuervain&#39;s Tenosynovitis, frozen shoulder, Piriformis Syndrome, Guyon&#39;s Canal Syndrome, thoracic kyphosis, and scar tissue conditions. Broadly speaking, the devices of the invention include a tensioning segment formed of elastic, stretchable material adapted for placement on a persons body proximal to the region of localized tissue compression, together with a plurality of elongated, adhesives straps secured at respective locations to the tensioning segment; the straps have less stretchability (and are preferably essentially non-stretchable) than the tensioning segment and are configured for securing the tensioning segment in place on a person&#39;s body. When applied, the tensioning segment of the device exerts yielding or tensile forces through the straps serving to at least partially reduce tissue compression. 
     In the case of a carpal tunnel syndrome treatment device, the tensioning segment is adapted to overlie the back of a person&#39;s hand, and has three individuals straps secured thereto. Two of the attachment straps are oriented to extend end opposite directions from the tensioning segment and to wrap about the heel of the person&#39;s hand below the person&#39;s thumb; the other of the straps is oriented to wrap about the person&#39;s hand between the thumb and forefinger. 
     In preferred forms, the tensioning segment includes an expansion indicator allowing the user to determine the extent of expansion of the segment upon application of the device. In practice, a circular marking on the tensioning segment is used for this purpose. Additionally, the tensioning segment is preferably formed at least in part of stretchable latex material, whereas the attachment straps are made of essentially nonstretchable polyethylene film coated with pressure are sensitive adhesive. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view all of a person&#39;s right hand (shown in phantom) with a preferred treatment device in accordance with the invention applied to the person&#39;s hand for the treatment of carpal tunnel syndrome; 
     FIG. 2 is a plan view of the preferred carpal tunnel syndrome treating device in accordance with the invention, with a left hand model being shown; 
     FIG. 3 is a sectional view taken long line  2 — 2  of FIG.  2  and illustrating one form of interconnection between the central tensioning segment of the device and the adhesive attachment straps; 
     FIG. 4 is an elevational view of the preferred treatment device of the invention, shown mounted on a person&#39;s left hand; 
     FIG. 5 is a view similar to that of FIG. 4, but showing the palm side of the person&#39;s left hand and the placement of the adhesive straps; and 
     FIG. 6 is a sectional view along line  6 — 6  of FIG.  5  and illustrating the manner in which the treatment device alleviates the symptoms of carpal tunnel syndrome. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Turning now to the drawings, and particularly FIGS. 2 and 3, a carpal tunnel syndrome treating device  10  is illustrated. Broadly speaking, the device  10  includes a central resilient tensioning segment  12  as well as three elongated straps  14 ,  16  and  18  secured to be segment  12 . The device  10  is designed to be applied to the hand  20  of a person in order to alleviate carpal tunnel syndrome symptoms. 
     In more detail, the tensioning segment  12  is made up of a pair of the arcuate, face-to-face oriented flexible sheets  22  and  24 , which are bonded together by adhesive  26  or direct thermal bonding of the sheets. As illustrated, the inboard ends of the straps  14 - 18  are received and bonded between the sheets  22 ,  24 , with the adhesive  26  serving to secure the straps in place; again, if the sheets  22 ,  24  are thermally bonded, the straps  14 - 18  would be secured thereto by virtue of such thermal bonding. An important feature of the invention resides in the fact that the segment  12  is formed of elastic, stretchable material which, when stretched, exerts a continuous yielding or tensile force on the straps  14 - 18 . To this end, it is preferred that the bottom sheet  24  is formed of conventional synthetic elastomer material, whereas the upper sheet  22  is formed of adhesive-bearing medical tape which is also stretchable with the sheet  24  (in this embodiment, the adhesive forming a part of the medical tape functions as the adhesive  26 ; in other cases a separately applied adhesive can be employed). It will also be seen that the upper sheet  22  has an expansion indicator  28  thereon, in the form of a circular marking. Where the tensioning segment  12  is formed of heat-bonded sheets, both such sheets may be formed of appropriate synthetic resin material such as Hysynal commercialized by Hygenic Corporation. The Hysynal product has a 300% modulus (ASTM D412) of 250 psi; a tensile strength (AS TM D412) of 2200 psi; an ultimate elongation ASTM D412) of 600%; and a durometer hardness (ASTM D2240) of 40±5 Shore A (plied). A typical latex rubber used for the fabrication of the segment  12  is the Hytone latex commercialized by Hygenic Corporation. This product has a 300% modulus of 130 psi, a tensile strength of 4000 psi, and an ultimate elongation of 780%. 
     Generally speaking, stretchable products used in this context should have a modulus of from about 75-400 psi, a tensile strength from about 1500-5000 psi, and an ultimate elongation of from about 200-1000% (ASTM D412). 
     Each of the straps  14 - 18  have significantly less stretchability than the tensioning segment  12 . Preferably, these straps are formed of essentially non-stretchable medical quality tape or ethylene vinyl acetate, with a layer  28  of conventional skin adhesive on the underside thereof. This adhesive is advantageously hypoallergenic in order to eliminate skin irritation. As seen, the opposed straps  14  end  16  have a width somewhat greater than that of the angularly oriented strap  18 . 
     It will be appreciated that the device  10  will be provided in left and right hand versions. The right hand version is illustrated in FIG. 1, whereas the left hand version is shown in FIGS. 2-5. 
     The device  10  is applied to the hand  20  of a person in the general manner shown in FIGS.  1  and  4 - 5 . That is, in the first step, the tensioning segment  12  is placed on the back of the person&#39;s hand. Next, the straps  14  and  16  are sequentially pulled and applied to the palm region of the hand  20  as best seen in FIG.  5 . During this application of the straps  14 ,  16 , the user observes the indicator  26 , and pulls the second-applied strap sufficiently to enlarge the indicator by approximately 30%. In the final step, the strap  18  is pulled upwardly and angularly between the thumb and forefinger of the hand, with the outer end of the strap being applied to the palm region of the hand  20  above the ends of the straps  14 ,  16 , insuring that the outboard ends of the straps  14 - 18  do not overlap in the palmar region. Here again, during application of the strap  18 , the indicator circle  26  is used so as to insure a substantially even expansion of the tensioning segment  12 . 
     In more detail, during the first week of using the device  10 , the tensioning segment  12  is placed on the back side of the hand, between the first bend of the small finger and where the wrist bends, with the straight edge of the segment  12  at the center of the hand. Next, the strap  14  is applied as described previously, followed by the straps  16  and  18 . During the first week, the device  12  is worn for period of  10 - 16  hours per day. During the second week of therapy, the segment  12  is placed on the back side of the hand,just distal to where the wrist bends on the side of the little finger, with the edge of the segment at the center of the hand. Placement of the straps  14 - 18  is the same as during the first week. After the second week, further use of the device  10  is carried out to achieve the most comfort and pain relief for the patient. 
     Attention is next directed to FIG. 6, which depicts the manner in which it is believed that the device  10  operates to alleviate the symptoms of carpal tunnel syndrome. As illustrated, the human wrist includes a complex of articulations and tendons including the Pisiform, Triquetral, Lunate, Capitate, and Scaphoid bones  30 - 38 , respectively, the common synovial sheath  40 , median nerve  42 , digit tendons  44 , ulnar artery  45 , ulnar nerve  45   a , and flexor retinaculum  46 . The carpal tunnel  48 , through which the median nerve  42  passes, is also illustrated in FIG.  6 . As explained previously, carpal tunnel syndrome involves a condition wherein the median nerve  42  and surrounding tissues are subjected to undue compression, which is accompanied by shortening of the flexor rentinaculum. 
     Use of the device  10  alleviates carpal tunnel syndrome symptoms by virtue of the continuing yielding or tensile forces exerted on the straps  14 - 18  by the tensioning segment  12 . That is, and as indicated by directional arrows  50 - 56 , the segment  12  effectively “pulls” at the area of the carpal tunnel and flexor rentinaculum to lengthen the latter, thereby enlarging the carpal tunnel  48  and relieving pressure on the median nerve  42  and ulnar nerve  45   a.    
     The device  10  is also advantageous in that it can be worn by a patient without interfering with the patient&#39;s normal activities; indeed, the device can be worn while sleeping or during daytime routines, even under gloves or other protective equipment. At the same time, the invention reduces the possible need for carpal tunnel syndrome surgery and obviates tiresome repetitive exercises and other related physical therapies. 
     Although a device for treating carpal tunnel syndrome has been specifically illustrated and described herein, it will be appreciated that the invention is not so limited. First and foremost, devices may be provided having as few as two straps and as many as needed for a particular condition. Thus, for the treatment of tennis elbow, it is anticipated that only a two-strap model would be required, with the central tensioning segment applied adjacent the proximal radial head of the radial bone, and with the two-straps extending in opposite directions therefrom. By exerting tension against the stronger muscle in this region, and providing more support for the adjacent weaker muscle, the tendency for the tissue to remain in an abnormal position is lessened, by reducing the intrinsic concentric muscular contraction. 
     Similarly, scar tissue conditions can be alleviated using devices in accordance with the invention. In such therapy, two of the devices would typically be used, one on each side of the scar formation. In this fashion, a stress is exerted in a direction parallel with the normal fiber orientation so as to stimulate reorientation of the involved scar tissue. 
     Patients suffering from trigger point muscle conditions can also be helped using the devices hereof. Two approaches can be used in this context. First, the device can be placed with one of the strap ends over the trigger point pain area, with the other strap end over a normal muscle. During motion, the applied device tends to extend the contracted trigger point muscle. Alternately, a plurality of individual devices may be placed about the trigger point muscle area to generate muscle extension forces.