Abstract:
An orthotic device and method for reducing muscle hypertonicity and contractures in patients with neurological disorders are provided. The device includes a hand support that is configured to receive and position a patient&#39;s hand in a manner such that the arches and fingers of the hand are extended and the finger knuckles do not bend toward the palm of the hand. The device also includes a forearm support which is pivotably connected to the hand support. The patient&#39;s hand is pivoted upwardly with the fingers extended which facilitates elongating the flexor tendons and muscles. In certain implementations, the device also includes an elbow support that is pivotably connected to the forearm support. The device and method are effective in spreading the metacarpals with finger and thumb extensions.

Description:
RELATED APPLICATIONS 
   This application claims the benefit of U.S. Provisional Application Ser. No. 60/580,928, filed Jun. 18, 2004, which is hereby incorporated by reference in its entirety. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   This invention relates generally to orthotic devices, and more particularly, to an orthotic device for use in rehabilitating individuals suffering from muscle spasticity, hypertonicity, and contractures which may be caused by stroke or brain injury. 
   2. Description of the Related Art 
   Patients with neurological disorders often suffer from muscle spasticity, hypertonicity and contractures which are usually caused by damages to the systems that control voluntary movements. Spasticity and hypertonicity are demonstrated when muscles receive improper nerve signals causing them to contract and become shortened. Improper control of brain signals is often due to damage within the brain caused by stroke, brain injury, or other traumas. 
   Contracture is one of the most detrimental consequences of spasticity or hypertonicity. Contractures are generally due to shortening of muscle fibers and other soft tissues and structural changes. When a muscle is not regularly put through its full range of movement, it can shorten and result in an abnormal condition including abnormal joint posture. This makes stretching the muscle difficult and may set up a vicious cycle of even more shortening and decreased stretch. The end result of untreated contracture is a long-term, often painful, abnormal posture, such as over-flexion of the hand or inversion of the foot. 
   One primary type of treatment for muscle spasticity, hypertonicity and contractures is regular stretching exercises including lengthening of flexors prescribed by a physical and occupational therapist. Early on in contracture development, range of motion exercises can help prevent permanent tendon shortening. Treatments for the upper extremities typically also include using a splint to position the patient&#39;s hand and wrist in a manner so as to keep them in a position that maintains range. The splint usually has a hand support contoured in the shape of the patient&#39;s hand in which the fingers are partially flexed and the wrist is extended. The hand support typically includes an interior surface or padding that directly contacts substantially the entire interior side of the hand, including the arch region. As such, the hand may be in a power position to flex on an object, which in turn can trigger more finger and thumb flexion. Thus, the occurrence of contractures may actually increase when the patient wears most conventional splints intended to reduce and manage the contractures. 
   In view of the foregoing, there is a need for an improved orthotic device and method for treating patients with muscle spasticity, hypertonicity and contractures. To this end, there is a particular need for an orthotic device and approach of treatment that reduces the occurrence of muscle over-activity while at the same time reverses muscle and tendon contractures. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of an orthotic device of one embodiment of the present invention; 
       FIG. 2  is a detailed view of the hand support of the orthotic device of  FIG. 1 ; 
       FIGS. 3A-3C  are schematic illustrates of the cross-section of the hand support of certain preferred embodiments; 
       FIG. 4  is a detailed view of the forearm support of the orthotic device of  FIG. 1 ; 
       FIGS. 5A-5D  illustrate an orthotic device of another embodiment of the present invention, including an elbow support; 
       FIG. 6  illustrates generally the manner in which a patient&#39;s hand is positioned in the orthotic device of one embodiment of the present invention and the manner in which the device can be used to stretch the flexor tendon of the patient; and 
       FIG. 7  illustrates a shoulder support used in conjunction with the orthotic device of certain preferred embodiments of the present invention. 
   

   SUMMARY OF THE INVENTION 
   In one aspect, the preferred embodiments of the present invention provide an orthotic device for reducing contracture and hypertonicity in patients with neurological disorders. The device includes a hand support, a forearm support, and attachment member that secures the device to the patient&#39;s forearm and hand. In one embodiment, the hand support is configured to receive and position a patient&#39;s hand in a manner such that the fingers of the hand are extended and the finger knuckles do not bend toward the palm of the hand. Preferably, the forearm support is pivotably connected to the hand support by a ratchet joint or other devices. The forearm support is configured to receive at least a portion of the patient&#39;s forearm. In one embodiment, the hand support has a substantially planar interior surface wherein the interior surface comprises the palm rest portion and a fingers rest portion. In another embodiment, the hand support comprises a palm rest portion and a thumb rest portion. Preferably, the thumb rest portion is pivotable relative to the palm portion rest such that the angle therebetween can be adjusted. In yet another embodiment, the hand support has a plurality of padding wherein the padding located in areas where the digit fingers of the patient&#39;s hand is to be positioned. 
   In another aspect, the preferred embodiments of the present invention provide an orthotic device having a hand support that includes a palm rest portion. Preferably, the palm rest portion has a central portion and a peripheral portion surrounding the central portion. Preferably, the central portion is not substantially higher than the peripheral portion so as to cause the palm to receive force substantially from the peripheral portion. In one embodiment, the central portion is substantially below the peripheral portion so that the palm of the patient&#39;s hand receives force substantially entirely from the peripheral portion. In another embodiment, the hand portion further comprises a fingertip portion. The fingertip portion is preferably at substantially the same level as the peripheral portion of the palm rest portion so as to allow extensions of the patient&#39;s fingers without bending the finger knuckles. 
   In yet another aspect, the preferred embodiments of the present invention provide a method of reducing muscle hypertonicity and contractures in patients with neurological disorders. The method comprises positioning the patient&#39;s hand in a hand support structure in a manner such that the arch of the hand is extended and the finger knuckles do not bend toward the palm of the hand. The method further comprises pivoting the patient&#39;s hand upwardly relatively to the wrist so as to elongate the patient&#39;s flexor tendon and muscles. In one embodiment, the method also includes securing the patient&#39;s forearm in a forearm support that is pivotably connected to the hand support structure. In another embodiment, the method also includes securing the patient&#39;s elbow in an elbow support that is pivotably connected to the forearm support. 
   DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     FIG. 1  illustrates an orthotic device  100  of one preferred embodiment of the present invention. As shown in  FIG. 1 , the device  100  generally includes a hand support  102  and a forearm support  104  which are movably interconnected by a joint  106 . Preferably, the hand support  102  and forearm support  104  are pivotable about a central axis  108  defined by the joint  106 . In one embodiment, the joint  106  is a ratchet joint known in the art. The ratchet joint can be locked in a plurality of different positions so that the hand support  102  and forearm support  104  can be affixed at various angles relative to each other. In one embodiment, the angle between the hand support  102  and forearm support  104  can be set at about 180 degrees, 150 degrees, 130 degrees, 100 degrees, and 90 degrees. Additionally, the hand support  102  and forearm support  104  can be applied and secured to a patient&#39;s hand and forearm respectively by straps  110  or other attachment devices. As will be described in greater detail below, the device  100  is configured to position the patient&#39;s hand and wrist in a manner so as to lengthen hypertonic muscles and reverse contractor of the flexors. 
     FIG. 2  further illustrates the hand support  102  of the orthotic device  100 . For illustration purposes, the hand support  102  is shown without the straps in this figure. As shown, the hand support  102  is configured in the general shape of a human hand. The hand support  102  can be made of a variety of different materials including rigid thermoplastic materials. Preferably, the hand support  102  has a main support portion  202  and a thumb support portion  204 . The thumb support portion  204  is configured to receive the thumb and preferably extends laterally from the main support portion  202 . In one implementation, the thumb support portion  204  is pivotable relative to the main support portion  202  such that the angle  208  between them can be adjusted. 
   In a preferred embodiment, the main support portion  202  has a palm rest portion  210  and a digit fingers rest portion  212 . The palm rest portion  210  includes a central portion  214  and a peripheral portion  216  which surrounds the central portion  214 . Preferably, the interior surface of the palm rest portion  210  is not substantially higher than the interior surface of peripheral portion  216  so that when the patient&#39;s hand is positioned in the hand support  102 , the palm receives force substantially entirely from the peripheral portion of the hand support. Moreover, the digit fingers rest portion  212  is preferably at the same level as the palm rest portion  210  so that the patient&#39;s fingers are extended without bending the knuckles. 
   In yet another preferred embodiment, the main support section  202  has a generally planar interior surface so as to allow full extension of the arches, metacarpal and fingers of the hand. However, it will be understood that the hand support  102  can be designed in any configuration that would allow the patient&#39;s hand to be positioned in a manner such that the hand lies relatively flat with the arch spread and the fingers extended and the finger knuckles do not bend toward the palm. 
     FIGS. 3A-3C  schematically illustrate the general cross-sectional profile of the main support portions of certain preferred implementations of the device. In the embodiment shown in  FIG. 3A , the main support portion  202  has a generally planar interior surface  302   a  configured to receive the patient&#39;s palm and digit fingers in a manner such that the hand lies flat against the interior surface of the hand support when the device is applied to the hand. In the embodiment shown in  FIG. 3B , the interior surface  302   b  of the main support portion  202  is contoured in a manner such that the central arch region  304   b  of the patient&#39;s hand does not contact the interior surface  302   b  of the hand support when the device is applied to the hand. In this implementation, the interior surface is concaved at the location where the central arch region of the hand is to be positioned so as to avoid applying pressure to the arch region and flexor tendon therein when the hand is pressed against the interior surface. In the embodiment shown in  FIG. 3C , one or more padding  306   c  is positioned on the inner surface  302   c  of the main support portion  202  at locations other than where the central arch region is to be positioned. In one embodiment, padding is placed at locations on the interior surface  302   c  which the patient&#39;s digit fingers are to be positioned so as to increase finger lift which allows for a fully extended position of the flexor tendon and muscles when excessive curling or flexion pattern is present. By avoiding contact with the central arch region of the hand and allowing the fingers to fully extend, the device  100  significantly reduces flexor spasticity or hypertonicity typically triggered by contacting or imparting pressure to the arch region and flexor tendon therein. As such, the orthotic device  100  is advantageously configured to elongate the flexor muscle while reducing muscle and tendon contracture, which provides a more effective therapeutic treatment for the patient than the known prior art orthotic devices and treatment systems. 
     FIG. 4  illustrates a detailed view of the forearm support  104  of the orthotic device  100 . As shown in  FIG. 3 , the forearm support  104  is formed of a rigid, elongate thermoplastic article having a curved inner surface  402  contoured to receive and support the patient&#39;s forearm when the patient&#39;s hand is positioned in the hand support  102 . The forearm support  104  is pivotably connected to the hand support by a ratchet joint. The forearm support  104  operates in conjunction with the hand support to maintain the patient&#39;s wrist and hand in a certain fixed angle. 
   In certain embodiments, as shown in  FIGS. 5A-D , the device  100  further includes an elbow support  500  that is configured to receive and support the elbow of the patient. As shown in  FIG. 5A , the elbow support  500  is pivotably connected to and interlocks with the forearm support  104  of the device  100  via an interconnect member  402 . A first end  403  of the interconnect member  402  is configured to pivotably attach to the elbow support  400  at a joint  406 . A second end  405  of the interconnect member  402  is configured to slidably engage with a channel  404  attached to the forearm support  104  of the device  100 . The distance between the elbow support  400  and the forearm support  104  can thus be adjusted by sliding the interconnect member  402  in and out of the channel  404 . This accommodates changes in the distance between the elbow support  400  and the forearm support  104  as the patient&#39;s forearm is raised or lowered relative to the elbow. In certain other embodiments, the device  100  also includes a shoulder support that is adapted to reduce the occurrence of traction of the shoulder. Instead of anchoring the shoulder support on the patient&#39;s back and neck area, the shoulder support of the preferred embodiment is anchored to the waist area of the patient. 
     FIG. 6  shows another embodiment of the orthotic device  100  which includes a shoulder support  602 . As shown, the shoulder support  602  is a U-shaped device adapted to hook to or be attached to the pants waist line of the patient. The shoulder support reduces the weight the device places on the patient&#39;s shoulder and also improves proper alignment of the patient&#39;s arm when the device is applied. 
   As shown in  FIG. 7 , when the device  100  is applied to the patient&#39;s hand  702 , the hand is supported by the hand support  102  and the forearm is positioned in and supported by the forearm support  104 . The orthotic device  100  is designed to elongate the patient&#39;s flexor tendon and extend the range of movement by pivoting the hand support  104  upwardly in the manner as shown in  FIG. 7 . As also shown, the patient&#39;s fingers  704  are extended and wrist is not in flexion when the hand is positioned in the device  100 . In one embodiment, the hand  702  is preferably positioned in a manner such that the fingers knuckles do not bend toward the palm of the hand. In this position, when the hand  702  is pivoted as shown in  FIG. 7 , the hand support exerts a force against the extended fingers  704 , which help spread the metacarpal and elongate the flexor tendon and muscles that extend along the hand and the forearm. In another embodiment, the hand  702  is positioned in a manner such that the central arch region of the hand does not contact any part of the device and/or the device does not impart any pressure to the flexor tendon therein when the hand is moved during therapy. As shown and described, the device is configured to pivot the hand in a direction opposite the flexion direction so as to reverse the contractures. The degree of pivot can be progressively increased during therapy. 
   It will be appreciated that the concept of an orthotic device that is designed to extend the arches regions and to not apply pressure to the arch regions of an extremity or the flexor tendon therein in order to reduce spasms and hypertonicity is not limited to hand, wrist, or arm orthotic devices, but can also be applied to orthotic devices for treatment of other parts of the body, such as the foot and ankle, with the philosophy of promoting the opposite of what abnormality is observed. 
   Although the foregoing description of certain preferred embodiments of the present invention has shown, described and pointed out the fundamental novel features of the invention, it will be understood that various omissions, substitutions, and changes in the form of the detail of the device and methods as illustrated as well as the uses thereof, may be made by those skilled in the art, without departing from the spirit of the invention. Consequently, the scope of the present invention should not be limited to the foregoing discussions.